Remove more of unused gnulib sources from contrib/tools/bison

6f612070e58cd7e6c16b0d090a809077b0a454ff

18 files changed, 0 insertions, 12957 deletions

diff --git a/contrib/tools/bison/lib/gettimeofday.c b/contrib/tools/bison/lib/gettimeofday.c
deleted file mode 100644
index ad65c6da8b..0000000000
--- a/contrib/tools/bison/lib/gettimeofday.c
+++ /dev/null
@@ -1,154 +0,0 @@
-/* Provide gettimeofday for systems that don't have it or for which it's broken.
-
-   Copyright (C) 2001-2003, 2005-2007, 2009-2013 Free Software Foundation, Inc.
-
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3, or (at your option)
-   any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program; if not, see <http://www.gnu.org/licenses/>.  */
-
-/* written by Jim Meyering */
-
-#include <config.h>
-
-/* Specification.  */
-#include <sys/time.h>
-
-#include <time.h>
-
-#if HAVE_SYS_TIMEB_H
-# include <sys/timeb.h>
-#endif
-
-#if GETTIMEOFDAY_CLOBBERS_LOCALTIME || TZSET_CLOBBERS_LOCALTIME
-
-/* Work around the bug in some systems whereby gettimeofday clobbers
-   the static buffer that localtime uses for its return value.  The
-   gettimeofday function from Mac OS X 10.0.4 (i.e., Darwin 1.3.7) has
-   this problem.  The tzset replacement is necessary for at least
-   Solaris 2.5, 2.5.1, and 2.6.  */
-
-static struct tm tm_zero_buffer;
-static struct tm *localtime_buffer_addr = &tm_zero_buffer;
-
-# undef localtime
-extern struct tm *localtime (time_t const *);
-
-# undef gmtime
-extern struct tm *gmtime (time_t const *);
-
-/* This is a wrapper for localtime.  It is used only on systems for which
-   gettimeofday clobbers the static buffer used for localtime's result.
-
-   On the first call, record the address of the static buffer that
-   localtime uses for its result.  */
-
-struct tm *
-rpl_localtime (time_t const *timep)
-{
-  struct tm *tm = localtime (timep);
-
-  if (localtime_buffer_addr == &tm_zero_buffer)
-    localtime_buffer_addr = tm;
-
-  return tm;
-}
-
-/* Same as above, since gmtime and localtime use the same buffer.  */
-struct tm *
-rpl_gmtime (time_t const *timep)
-{
-  struct tm *tm = gmtime (timep);
-
-  if (localtime_buffer_addr == &tm_zero_buffer)
-    localtime_buffer_addr = tm;
-
-  return tm;
-}
-
-#endif /* GETTIMEOFDAY_CLOBBERS_LOCALTIME || TZSET_CLOBBERS_LOCALTIME */
-
-#if TZSET_CLOBBERS_LOCALTIME
-
-# undef tzset
-extern void tzset (void);
-
-/* This is a wrapper for tzset, for systems on which tzset may clobber
-   the static buffer used for localtime's result.  */
-void
-rpl_tzset (void)
-{
-  /* Save and restore the contents of the buffer used for localtime's
-     result around the call to tzset.  */
-  struct tm save = *localtime_buffer_addr;
-  tzset ();
-  *localtime_buffer_addr = save;
-}
-#endif
-
-/* This is a wrapper for gettimeofday.  It is used only on systems
-   that lack this function, or whose implementation of this function
-   causes problems.  */
-
-int
-gettimeofday (struct timeval *restrict tv, void *restrict tz)
-{
-#undef gettimeofday
-#if HAVE_GETTIMEOFDAY
-# if GETTIMEOFDAY_CLOBBERS_LOCALTIME
-  /* Save and restore the contents of the buffer used for localtime's
-     result around the call to gettimeofday.  */
-  struct tm save = *localtime_buffer_addr;
-# endif
-
-# if defined timeval /* 'struct timeval' overridden by gnulib?  */
-#  undef timeval
-  struct timeval otv;
-  int result = gettimeofday (&otv, (struct timezone *) tz);
-  if (result == 0)
-    {
-      tv->tv_sec = otv.tv_sec;
-      tv->tv_usec = otv.tv_usec;
-    }
-# else
-  int result = gettimeofday (tv, (struct timezone *) tz);
-# endif
-
-# if GETTIMEOFDAY_CLOBBERS_LOCALTIME
-  *localtime_buffer_addr = save;
-# endif
-
-  return result;
-
-#else
-
-# if HAVE__FTIME
-
-  struct _timeb timebuf;
-  _ftime (&timebuf);
-  tv->tv_sec = timebuf.time;
-  tv->tv_usec = timebuf.millitm * 1000;
-
-# else
-
-#  if !defined OK_TO_USE_1S_CLOCK
-#   error "Only 1-second nominal clock resolution found.  Is that intended?" \
-          "If so, compile with the -DOK_TO_USE_1S_CLOCK option."
-#  endif
-  tv->tv_sec = time (NULL);
-  tv->tv_usec = 0;
-
-# endif
-
-  return 0;
-
-#endif
-}
diff --git a/contrib/tools/bison/lib/memchr2.c b/contrib/tools/bison/lib/memchr2.c
deleted file mode 100644
index 8b105b7f27..0000000000
--- a/contrib/tools/bison/lib/memchr2.c
+++ /dev/null
@@ -1,169 +0,0 @@
-/* Copyright (C) 1991, 1993, 1996-1997, 1999-2000, 2003-2004, 2006, 2008-2013
-   Free Software Foundation, Inc.
-
-   Based on strlen implementation by Torbjorn Granlund (tege@sics.se),
-   with help from Dan Sahlin (dan@sics.se) and
-   commentary by Jim Blandy (jimb@ai.mit.edu);
-   adaptation to memchr suggested by Dick Karpinski (dick@cca.ucsf.edu),
-   and implemented in glibc by Roland McGrath (roland@ai.mit.edu).
-   Extension to memchr2 implemented by Eric Blake (ebb9@byu.net).
-
-This program is free software: you can redistribute it and/or modify it
-under the terms of the GNU General Public License as published by the
-Free Software Foundation; either version 3 of the License, or any
-later version.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-#include <config.h>
-
-#include "memchr2.h"
-
-#include <limits.h>
-#include <stdint.h>
-#include <string.h>
-
-/* Return the first address of either C1 or C2 (treated as unsigned
-   char) that occurs within N bytes of the memory region S.  If
-   neither byte appears, return NULL.  */
-void *
-memchr2 (void const *s, int c1_in, int c2_in, size_t n)
-{
-  /* On 32-bit hardware, choosing longword to be a 32-bit unsigned
-     long instead of a 64-bit uintmax_t tends to give better
-     performance.  On 64-bit hardware, unsigned long is generally 64
-     bits already.  Change this typedef to experiment with
-     performance.  */
-  typedef unsigned long int longword;
-
-  const unsigned char *char_ptr;
-  void const *void_ptr;
-  const longword *longword_ptr;
-  longword repeated_one;
-  longword repeated_c1;
-  longword repeated_c2;
-  unsigned char c1;
-  unsigned char c2;
-
-  c1 = (unsigned char) c1_in;
-  c2 = (unsigned char) c2_in;
-
-  if (c1 == c2)
-    return memchr (s, c1, n);
-
-  /* Handle the first few bytes by reading one byte at a time.
-     Do this until VOID_PTR is aligned on a longword boundary.  */
-  for (void_ptr = s;
-       n > 0 && (uintptr_t) void_ptr % sizeof (longword) != 0;
-       --n)
-    {
-      char_ptr = void_ptr;
-      if (*char_ptr == c1 || *char_ptr == c2)
-        return (void *) void_ptr;
-      void_ptr = char_ptr + 1;
-    }
-
-  longword_ptr = void_ptr;
-
-  /* All these elucidatory comments refer to 4-byte longwords,
-     but the theory applies equally well to any size longwords.  */
-
-  /* Compute auxiliary longword values:
-     repeated_one is a value which has a 1 in every byte.
-     repeated_c1 has c1 in every byte.
-     repeated_c2 has c2 in every byte.  */
-  repeated_one = 0x01010101;
-  repeated_c1 = c1 | (c1 << 8);
-  repeated_c2 = c2 | (c2 << 8);
-  repeated_c1 |= repeated_c1 << 16;
-  repeated_c2 |= repeated_c2 << 16;
-  if (0xffffffffU < (longword) -1)
-    {
-      repeated_one |= repeated_one << 31 << 1;
-      repeated_c1 |= repeated_c1 << 31 << 1;
-      repeated_c2 |= repeated_c2 << 31 << 1;
-      if (8 < sizeof (longword))
-        {
-          size_t i;
-
-          for (i = 64; i < sizeof (longword) * 8; i *= 2)
-            {
-              repeated_one |= repeated_one << i;
-              repeated_c1 |= repeated_c1 << i;
-              repeated_c2 |= repeated_c2 << i;
-            }
-        }
-    }
-
-  /* Instead of the traditional loop which tests each byte, we will test a
-     longword at a time.  The tricky part is testing if *any of the four*
-     bytes in the longword in question are equal to c1 or c2.  We first use
-     an xor with repeated_c1 and repeated_c2, respectively.  This reduces
-     the task to testing whether *any of the four* bytes in longword1 or
-     longword2 is zero.
-
-     Let's consider longword1.  We compute tmp1 =
-       ((longword1 - repeated_one) & ~longword1) & (repeated_one << 7).
-     That is, we perform the following operations:
-       1. Subtract repeated_one.
-       2. & ~longword1.
-       3. & a mask consisting of 0x80 in every byte.
-     Consider what happens in each byte:
-       - If a byte of longword1 is zero, step 1 and 2 transform it into 0xff,
-         and step 3 transforms it into 0x80.  A carry can also be propagated
-         to more significant bytes.
-       - If a byte of longword1 is nonzero, let its lowest 1 bit be at
-         position k (0 <= k <= 7); so the lowest k bits are 0.  After step 1,
-         the byte ends in a single bit of value 0 and k bits of value 1.
-         After step 2, the result is just k bits of value 1: 2^k - 1.  After
-         step 3, the result is 0.  And no carry is produced.
-     So, if longword1 has only non-zero bytes, tmp1 is zero.
-     Whereas if longword1 has a zero byte, call j the position of the least
-     significant zero byte.  Then the result has a zero at positions 0, ...,
-     j-1 and a 0x80 at position j.  We cannot predict the result at the more
-     significant bytes (positions j+1..3), but it does not matter since we
-     already have a non-zero bit at position 8*j+7.
-
-     Similarly, we compute tmp2 =
-       ((longword2 - repeated_one) & ~longword2) & (repeated_one << 7).
-
-     The test whether any byte in longword1 or longword2 is zero is equivalent
-     to testing whether tmp1 is nonzero or tmp2 is nonzero.  We can combine
-     this into a single test, whether (tmp1 | tmp2) is nonzero.  */
-
-  while (n >= sizeof (longword))
-    {
-      longword longword1 = *longword_ptr ^ repeated_c1;
-      longword longword2 = *longword_ptr ^ repeated_c2;
-
-      if (((((longword1 - repeated_one) & ~longword1)
-            | ((longword2 - repeated_one) & ~longword2))
-           & (repeated_one << 7)) != 0)
-        break;
-      longword_ptr++;
-      n -= sizeof (longword);
-    }
-
-  char_ptr = (const unsigned char *) longword_ptr;
-
-  /* At this point, we know that either n < sizeof (longword), or one of the
-     sizeof (longword) bytes starting at char_ptr is == c1 or == c2.  On
-     little-endian machines, we could determine the first such byte without
-     any further memory accesses, just by looking at the (tmp1 | tmp2) result
-     from the last loop iteration.  But this does not work on big-endian
-     machines.  Choose code that works in both cases.  */
-
-  for (; n > 0; --n, ++char_ptr)
-    {
-      if (*char_ptr == c1 || *char_ptr == c2)
-        return (void *) char_ptr;
-    }
-
-  return NULL;
-}
diff --git a/contrib/tools/bison/lib/memchr2.h b/contrib/tools/bison/lib/memchr2.h
deleted file mode 100644
index cc04889f12..0000000000
--- a/contrib/tools/bison/lib/memchr2.h
+++ /dev/null
@@ -1,32 +0,0 @@
-/* Scan memory for the first of two bytes.
-   Copyright (C) 2008-2013 Free Software Foundation, Inc.
-
-   This program is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-#include <stddef.h>
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* Return the first address of either C1 or C2 (treated as unsigned
-   char) that occurs within N bytes of the memory region S.  If
-   neither byte appears, return NULL.  */
-
-extern void *memchr2 (void const *s, int c1, int c2, size_t n)
-  _GL_ATTRIBUTE_PURE;
-
-#ifdef __cplusplus
-}
-#endif
diff --git a/contrib/tools/bison/lib/realloc.c b/contrib/tools/bison/lib/realloc.c
deleted file mode 100644
index b51010a621..0000000000
--- a/contrib/tools/bison/lib/realloc.c
+++ /dev/null
@@ -1,79 +0,0 @@
-/* realloc() function that is glibc compatible.
-
-   Copyright (C) 1997, 2003-2004, 2006-2007, 2009-2013 Free Software
-   Foundation, Inc.
-
-   This program is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-/* written by Jim Meyering and Bruno Haible */
-
-#define _GL_USE_STDLIB_ALLOC 1
-#include <config.h>
-
-/* Only the AC_FUNC_REALLOC macro defines 'realloc' already in config.h.  */
-#ifdef realloc
-# define NEED_REALLOC_GNU 1
-/* Whereas the gnulib module 'realloc-gnu' defines HAVE_REALLOC_GNU.  */
-#elif GNULIB_REALLOC_GNU && !HAVE_REALLOC_GNU
-# define NEED_REALLOC_GNU 1
-#endif
-
-/* Infer the properties of the system's malloc function.
-   The gnulib module 'malloc-gnu' defines HAVE_MALLOC_GNU.  */
-#if GNULIB_MALLOC_GNU && HAVE_MALLOC_GNU
-# define SYSTEM_MALLOC_GLIBC_COMPATIBLE 1
-#endif
-
-#include <stdlib.h>
-
-#include <errno.h>
-
-/* Change the size of an allocated block of memory P to N bytes,
-   with error checking.  If N is zero, change it to 1.  If P is NULL,
-   use malloc.  */
-
-void *
-rpl_realloc (void *p, size_t n)
-{
-  void *result;
-
-#if NEED_REALLOC_GNU
-  if (n == 0)
-    {
-      n = 1;
-
-      /* In theory realloc might fail, so don't rely on it to free.  */
-      free (p);
-      p = NULL;
-    }
-#endif
-
-  if (p == NULL)
-    {
-#if GNULIB_REALLOC_GNU && !NEED_REALLOC_GNU && !SYSTEM_MALLOC_GLIBC_COMPATIBLE
-      if (n == 0)
-        n = 1;
-#endif
-      result = malloc (n);
-    }
-  else
-    result = realloc (p, n);
-
-#if !HAVE_REALLOC_POSIX
-  if (result == NULL)
-    errno = ENOMEM;
-#endif
-
-  return result;
-}
diff --git a/contrib/tools/bison/lib/regcomp.c b/contrib/tools/bison/lib/regcomp.c
deleted file mode 100644
index f0b2e52216..0000000000
--- a/contrib/tools/bison/lib/regcomp.c
+++ /dev/null
@@ -1,3922 +0,0 @@
-/* Extended regular expression matching and search library.
-   Copyright (C) 2002-2013 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-   Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU General Public
-   License as published by the Free Software Foundation; either
-   version 3 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   General Public License for more details.
-
-   You should have received a copy of the GNU General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-static reg_errcode_t re_compile_internal (regex_t *preg, const char * pattern,
-					  size_t length, reg_syntax_t syntax);
-static void re_compile_fastmap_iter (regex_t *bufp,
-				     const re_dfastate_t *init_state,
-				     char *fastmap);
-static reg_errcode_t init_dfa (re_dfa_t *dfa, size_t pat_len);
-#ifdef RE_ENABLE_I18N
-static void free_charset (re_charset_t *cset);
-#endif /* RE_ENABLE_I18N */
-static void free_workarea_compile (regex_t *preg);
-static reg_errcode_t create_initial_state (re_dfa_t *dfa);
-#ifdef RE_ENABLE_I18N
-static void optimize_utf8 (re_dfa_t *dfa);
-#endif
-static reg_errcode_t analyze (regex_t *preg);
-static reg_errcode_t preorder (bin_tree_t *root,
-			       reg_errcode_t (fn (void *, bin_tree_t *)),
-			       void *extra);
-static reg_errcode_t postorder (bin_tree_t *root,
-				reg_errcode_t (fn (void *, bin_tree_t *)),
-				void *extra);
-static reg_errcode_t optimize_subexps (void *extra, bin_tree_t *node);
-static reg_errcode_t lower_subexps (void *extra, bin_tree_t *node);
-static bin_tree_t *lower_subexp (reg_errcode_t *err, regex_t *preg,
-				 bin_tree_t *node);
-static reg_errcode_t calc_first (void *extra, bin_tree_t *node);
-static reg_errcode_t calc_next (void *extra, bin_tree_t *node);
-static reg_errcode_t link_nfa_nodes (void *extra, bin_tree_t *node);
-static Idx duplicate_node (re_dfa_t *dfa, Idx org_idx, unsigned int constraint);
-static Idx search_duplicated_node (const re_dfa_t *dfa, Idx org_node,
-				   unsigned int constraint);
-static reg_errcode_t calc_eclosure (re_dfa_t *dfa);
-static reg_errcode_t calc_eclosure_iter (re_node_set *new_set, re_dfa_t *dfa,
-					 Idx node, bool root);
-static reg_errcode_t calc_inveclosure (re_dfa_t *dfa);
-static Idx fetch_number (re_string_t *input, re_token_t *token,
-			 reg_syntax_t syntax);
-static int peek_token (re_token_t *token, re_string_t *input,
-			reg_syntax_t syntax) internal_function;
-static bin_tree_t *parse (re_string_t *regexp, regex_t *preg,
-			  reg_syntax_t syntax, reg_errcode_t *err);
-static bin_tree_t *parse_reg_exp (re_string_t *regexp, regex_t *preg,
-				  re_token_t *token, reg_syntax_t syntax,
-				  Idx nest, reg_errcode_t *err);
-static bin_tree_t *parse_branch (re_string_t *regexp, regex_t *preg,
-				 re_token_t *token, reg_syntax_t syntax,
-				 Idx nest, reg_errcode_t *err);
-static bin_tree_t *parse_expression (re_string_t *regexp, regex_t *preg,
-				     re_token_t *token, reg_syntax_t syntax,
-				     Idx nest, reg_errcode_t *err);
-static bin_tree_t *parse_sub_exp (re_string_t *regexp, regex_t *preg,
-				  re_token_t *token, reg_syntax_t syntax,
-				  Idx nest, reg_errcode_t *err);
-static bin_tree_t *parse_dup_op (bin_tree_t *dup_elem, re_string_t *regexp,
-				 re_dfa_t *dfa, re_token_t *token,
-				 reg_syntax_t syntax, reg_errcode_t *err);
-static bin_tree_t *parse_bracket_exp (re_string_t *regexp, re_dfa_t *dfa,
-				      re_token_t *token, reg_syntax_t syntax,
-				      reg_errcode_t *err);
-static reg_errcode_t parse_bracket_element (bracket_elem_t *elem,
-					    re_string_t *regexp,
-					    re_token_t *token, int token_len,
-					    re_dfa_t *dfa,
-					    reg_syntax_t syntax,
-					    bool accept_hyphen);
-static reg_errcode_t parse_bracket_symbol (bracket_elem_t *elem,
-					  re_string_t *regexp,
-					  re_token_t *token);
-#ifdef RE_ENABLE_I18N
-static reg_errcode_t build_equiv_class (bitset_t sbcset,
-					re_charset_t *mbcset,
-					Idx *equiv_class_alloc,
-					const unsigned char *name);
-static reg_errcode_t build_charclass (RE_TRANSLATE_TYPE trans,
-				      bitset_t sbcset,
-				      re_charset_t *mbcset,
-				      Idx *char_class_alloc,
-				      const char *class_name,
-				      reg_syntax_t syntax);
-#else  /* not RE_ENABLE_I18N */
-static reg_errcode_t build_equiv_class (bitset_t sbcset,
-					const unsigned char *name);
-static reg_errcode_t build_charclass (RE_TRANSLATE_TYPE trans,
-				      bitset_t sbcset,
-				      const char *class_name,
-				      reg_syntax_t syntax);
-#endif /* not RE_ENABLE_I18N */
-static bin_tree_t *build_charclass_op (re_dfa_t *dfa,
-				       RE_TRANSLATE_TYPE trans,
-				       const char *class_name,
-				       const char *extra,
-				       bool non_match, reg_errcode_t *err);
-static bin_tree_t *create_tree (re_dfa_t *dfa,
-				bin_tree_t *left, bin_tree_t *right,
-				re_token_type_t type);
-static bin_tree_t *create_token_tree (re_dfa_t *dfa,
-				      bin_tree_t *left, bin_tree_t *right,
-				      const re_token_t *token);
-static bin_tree_t *duplicate_tree (const bin_tree_t *src, re_dfa_t *dfa);
-static void free_token (re_token_t *node);
-static reg_errcode_t free_tree (void *extra, bin_tree_t *node);
-static reg_errcode_t mark_opt_subexp (void *extra, bin_tree_t *node);
-
-/* This table gives an error message for each of the error codes listed
-   in regex.h.  Obviously the order here has to be same as there.
-   POSIX doesn't require that we do anything for REG_NOERROR,
-   but why not be nice?  */
-
-static const char __re_error_msgid[] =
-  {
-#define REG_NOERROR_IDX	0
-    gettext_noop ("Success")	/* REG_NOERROR */
-    "\0"
-#define REG_NOMATCH_IDX (REG_NOERROR_IDX + sizeof "Success")
-    gettext_noop ("No match")	/* REG_NOMATCH */
-    "\0"
-#define REG_BADPAT_IDX	(REG_NOMATCH_IDX + sizeof "No match")
-    gettext_noop ("Invalid regular expression") /* REG_BADPAT */
-    "\0"
-#define REG_ECOLLATE_IDX (REG_BADPAT_IDX + sizeof "Invalid regular expression")
-    gettext_noop ("Invalid collation character") /* REG_ECOLLATE */
-    "\0"
-#define REG_ECTYPE_IDX	(REG_ECOLLATE_IDX + sizeof "Invalid collation character")
-    gettext_noop ("Invalid character class name") /* REG_ECTYPE */
-    "\0"
-#define REG_EESCAPE_IDX	(REG_ECTYPE_IDX + sizeof "Invalid character class name")
-    gettext_noop ("Trailing backslash") /* REG_EESCAPE */
-    "\0"
-#define REG_ESUBREG_IDX	(REG_EESCAPE_IDX + sizeof "Trailing backslash")
-    gettext_noop ("Invalid back reference") /* REG_ESUBREG */
-    "\0"
-#define REG_EBRACK_IDX	(REG_ESUBREG_IDX + sizeof "Invalid back reference")
-    gettext_noop ("Unmatched [ or [^")	/* REG_EBRACK */
-    "\0"
-#define REG_EPAREN_IDX	(REG_EBRACK_IDX + sizeof "Unmatched [ or [^")
-    gettext_noop ("Unmatched ( or \\(") /* REG_EPAREN */
-    "\0"
-#define REG_EBRACE_IDX	(REG_EPAREN_IDX + sizeof "Unmatched ( or \\(")
-    gettext_noop ("Unmatched \\{") /* REG_EBRACE */
-    "\0"
-#define REG_BADBR_IDX	(REG_EBRACE_IDX + sizeof "Unmatched \\{")
-    gettext_noop ("Invalid content of \\{\\}") /* REG_BADBR */
-    "\0"
-#define REG_ERANGE_IDX	(REG_BADBR_IDX + sizeof "Invalid content of \\{\\}")
-    gettext_noop ("Invalid range end")	/* REG_ERANGE */
-    "\0"
-#define REG_ESPACE_IDX	(REG_ERANGE_IDX + sizeof "Invalid range end")
-    gettext_noop ("Memory exhausted") /* REG_ESPACE */
-    "\0"
-#define REG_BADRPT_IDX	(REG_ESPACE_IDX + sizeof "Memory exhausted")
-    gettext_noop ("Invalid preceding regular expression") /* REG_BADRPT */
-    "\0"
-#define REG_EEND_IDX	(REG_BADRPT_IDX + sizeof "Invalid preceding regular expression")
-    gettext_noop ("Premature end of regular expression") /* REG_EEND */
-    "\0"
-#define REG_ESIZE_IDX	(REG_EEND_IDX + sizeof "Premature end of regular expression")
-    gettext_noop ("Regular expression too big") /* REG_ESIZE */
-    "\0"
-#define REG_ERPAREN_IDX	(REG_ESIZE_IDX + sizeof "Regular expression too big")
-    gettext_noop ("Unmatched ) or \\)") /* REG_ERPAREN */
-  };
-
-static const size_t __re_error_msgid_idx[] =
-  {
-    REG_NOERROR_IDX,
-    REG_NOMATCH_IDX,
-    REG_BADPAT_IDX,
-    REG_ECOLLATE_IDX,
-    REG_ECTYPE_IDX,
-    REG_EESCAPE_IDX,
-    REG_ESUBREG_IDX,
-    REG_EBRACK_IDX,
-    REG_EPAREN_IDX,
-    REG_EBRACE_IDX,
-    REG_BADBR_IDX,
-    REG_ERANGE_IDX,
-    REG_ESPACE_IDX,
-    REG_BADRPT_IDX,
-    REG_EEND_IDX,
-    REG_ESIZE_IDX,
-    REG_ERPAREN_IDX
-  };
-
-/* Entry points for GNU code.  */
-
-/* re_compile_pattern is the GNU regular expression compiler: it
-   compiles PATTERN (of length LENGTH) and puts the result in BUFP.
-   Returns 0 if the pattern was valid, otherwise an error string.
-
-   Assumes the 'allocated' (and perhaps 'buffer') and 'translate' fields
-   are set in BUFP on entry.  */
-
-#ifdef _LIBC
-const char *
-re_compile_pattern (pattern, length, bufp)
-    const char *pattern;
-    size_t length;
-    struct re_pattern_buffer *bufp;
-#else /* size_t might promote */
-const char *
-re_compile_pattern (const char *pattern, size_t length,
-		    struct re_pattern_buffer *bufp)
-#endif
-{
-  reg_errcode_t ret;
-
-  /* And GNU code determines whether or not to get register information
-     by passing null for the REGS argument to re_match, etc., not by
-     setting no_sub, unless RE_NO_SUB is set.  */
-  bufp->no_sub = !!(re_syntax_options & RE_NO_SUB);
-
-  /* Match anchors at newline.  */
-  bufp->newline_anchor = 1;
-
-  ret = re_compile_internal (bufp, pattern, length, re_syntax_options);
-
-  if (!ret)
-    return NULL;
-  return gettext (__re_error_msgid + __re_error_msgid_idx[(int) ret]);
-}
-#ifdef _LIBC
-weak_alias (__re_compile_pattern, re_compile_pattern)
-#endif
-
-/* Set by 're_set_syntax' to the current regexp syntax to recognize.  Can
-   also be assigned to arbitrarily: each pattern buffer stores its own
-   syntax, so it can be changed between regex compilations.  */
-/* This has no initializer because initialized variables in Emacs
-   become read-only after dumping.  */
-reg_syntax_t re_syntax_options;
-
-
-/* Specify the precise syntax of regexps for compilation.  This provides
-   for compatibility for various utilities which historically have
-   different, incompatible syntaxes.
-
-   The argument SYNTAX is a bit mask comprised of the various bits
-   defined in regex.h.  We return the old syntax.  */
-
-reg_syntax_t
-re_set_syntax (syntax)
-    reg_syntax_t syntax;
-{
-  reg_syntax_t ret = re_syntax_options;
-
-  re_syntax_options = syntax;
-  return ret;
-}
-#ifdef _LIBC
-weak_alias (__re_set_syntax, re_set_syntax)
-#endif
-
-int
-re_compile_fastmap (bufp)
-    struct re_pattern_buffer *bufp;
-{
-  re_dfa_t *dfa = bufp->buffer;
-  char *fastmap = bufp->fastmap;
-
-  memset (fastmap, '\0', sizeof (char) * SBC_MAX);
-  re_compile_fastmap_iter (bufp, dfa->init_state, fastmap);
-  if (dfa->init_state != dfa->init_state_word)
-    re_compile_fastmap_iter (bufp, dfa->init_state_word, fastmap);
-  if (dfa->init_state != dfa->init_state_nl)
-    re_compile_fastmap_iter (bufp, dfa->init_state_nl, fastmap);
-  if (dfa->init_state != dfa->init_state_begbuf)
-    re_compile_fastmap_iter (bufp, dfa->init_state_begbuf, fastmap);
-  bufp->fastmap_accurate = 1;
-  return 0;
-}
-#ifdef _LIBC
-weak_alias (__re_compile_fastmap, re_compile_fastmap)
-#endif
-
-static inline void
-__attribute__ ((always_inline))
-re_set_fastmap (char *fastmap, bool icase, int ch)
-{
-  fastmap[ch] = 1;
-  if (icase)
-    fastmap[tolower (ch)] = 1;
-}
-
-/* Helper function for re_compile_fastmap.
-   Compile fastmap for the initial_state INIT_STATE.  */
-
-static void
-re_compile_fastmap_iter (regex_t *bufp, const re_dfastate_t *init_state,
-			 char *fastmap)
-{
-  re_dfa_t *dfa = bufp->buffer;
-  Idx node_cnt;
-  bool icase = (dfa->mb_cur_max == 1 && (bufp->syntax & RE_ICASE));
-  for (node_cnt = 0; node_cnt < init_state->nodes.nelem; ++node_cnt)
-    {
-      Idx node = init_state->nodes.elems[node_cnt];
-      re_token_type_t type = dfa->nodes[node].type;
-
-      if (type == CHARACTER)
-	{
-	  re_set_fastmap (fastmap, icase, dfa->nodes[node].opr.c);
-#ifdef RE_ENABLE_I18N
-	  if ((bufp->syntax & RE_ICASE) && dfa->mb_cur_max > 1)
-	    {
-	      unsigned char buf[MB_LEN_MAX];
-	      unsigned char *p;
-	      wchar_t wc;
-	      mbstate_t state;
-
-	      p = buf;
-	      *p++ = dfa->nodes[node].opr.c;
-	      while (++node < dfa->nodes_len
-		     &&	dfa->nodes[node].type == CHARACTER
-		     && dfa->nodes[node].mb_partial)
-		*p++ = dfa->nodes[node].opr.c;
-	      memset (&state, '\0', sizeof (state));
-	      if (__mbrtowc (&wc, (const char *) buf, p - buf,
-			     &state) == p - buf
-		  && (__wcrtomb ((char *) buf, towlower (wc), &state)
-		      != (size_t) -1))
-		re_set_fastmap (fastmap, false, buf[0]);
-	    }
-#endif
-	}
-      else if (type == SIMPLE_BRACKET)
-	{
-	  int i, ch;
-	  for (i = 0, ch = 0; i < BITSET_WORDS; ++i)
-	    {
-	      int j;
-	      bitset_word_t w = dfa->nodes[node].opr.sbcset[i];
-	      for (j = 0; j < BITSET_WORD_BITS; ++j, ++ch)
-		if (w & ((bitset_word_t) 1 << j))
-		  re_set_fastmap (fastmap, icase, ch);
-	    }
-	}
-#ifdef RE_ENABLE_I18N
-      else if (type == COMPLEX_BRACKET)
-	{
-	  re_charset_t *cset = dfa->nodes[node].opr.mbcset;
-	  Idx i;
-
-# ifdef _LIBC
-	  /* See if we have to try all bytes which start multiple collation
-	     elements.
-	     e.g. In da_DK, we want to catch 'a' since "aa" is a valid
-		  collation element, and don't catch 'b' since 'b' is
-		  the only collation element which starts from 'b' (and
-		  it is caught by SIMPLE_BRACKET).  */
-	      if (_NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES) != 0
-		  && (cset->ncoll_syms || cset->nranges))
-		{
-		  const int32_t *table = (const int32_t *)
-		    _NL_CURRENT (LC_COLLATE, _NL_COLLATE_TABLEMB);
-		  for (i = 0; i < SBC_MAX; ++i)
-		    if (table[i] < 0)
-		      re_set_fastmap (fastmap, icase, i);
-		}
-# endif /* _LIBC */
-
-	  /* See if we have to start the match at all multibyte characters,
-	     i.e. where we would not find an invalid sequence.  This only
-	     applies to multibyte character sets; for single byte character
-	     sets, the SIMPLE_BRACKET again suffices.  */
-	  if (dfa->mb_cur_max > 1
-	      && (cset->nchar_classes || cset->non_match || cset->nranges
-# ifdef _LIBC
-		  || cset->nequiv_classes
-# endif /* _LIBC */
-		 ))
-	    {
-	      unsigned char c = 0;
-	      do
-		{
-		  mbstate_t mbs;
-		  memset (&mbs, 0, sizeof (mbs));
-		  if (__mbrtowc (NULL, (char *) &c, 1, &mbs) == (size_t) -2)
-		    re_set_fastmap (fastmap, false, (int) c);
-		}
-	      while (++c != 0);
-	    }
-
-	  else
-	    {
-	      /* ... Else catch all bytes which can start the mbchars.  */
-	      for (i = 0; i < cset->nmbchars; ++i)
-		{
-		  char buf[256];
-		  mbstate_t state;
-		  memset (&state, '\0', sizeof (state));
-		  if (__wcrtomb (buf, cset->mbchars[i], &state) != (size_t) -1)
-		    re_set_fastmap (fastmap, icase, *(unsigned char *) buf);
-		  if ((bufp->syntax & RE_ICASE) && dfa->mb_cur_max > 1)
-		    {
-		      if (__wcrtomb (buf, towlower (cset->mbchars[i]), &state)
-			  != (size_t) -1)
-			re_set_fastmap (fastmap, false, *(unsigned char *) buf);
-		    }
-		}
-	    }
-	}
-#endif /* RE_ENABLE_I18N */
-      else if (type == OP_PERIOD
-#ifdef RE_ENABLE_I18N
-	       || type == OP_UTF8_PERIOD
-#endif /* RE_ENABLE_I18N */
-	       || type == END_OF_RE)
-	{
-	  memset (fastmap, '\1', sizeof (char) * SBC_MAX);
-	  if (type == END_OF_RE)
-	    bufp->can_be_null = 1;
-	  return;
-	}
-    }
-}
-
-/* Entry point for POSIX code.  */
-/* regcomp takes a regular expression as a string and compiles it.
-
-   PREG is a regex_t *.  We do not expect any fields to be initialized,
-   since POSIX says we shouldn't.  Thus, we set
-
-     'buffer' to the compiled pattern;
-     'used' to the length of the compiled pattern;
-     'syntax' to RE_SYNTAX_POSIX_EXTENDED if the
-       REG_EXTENDED bit in CFLAGS is set; otherwise, to
-       RE_SYNTAX_POSIX_BASIC;
-     'newline_anchor' to REG_NEWLINE being set in CFLAGS;
-     'fastmap' to an allocated space for the fastmap;
-     'fastmap_accurate' to zero;
-     're_nsub' to the number of subexpressions in PATTERN.
-
-   PATTERN is the address of the pattern string.
-
-   CFLAGS is a series of bits which affect compilation.
-
-     If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
-     use POSIX basic syntax.
-
-     If REG_NEWLINE is set, then . and [^...] don't match newline.
-     Also, regexec will try a match beginning after every newline.
-
-     If REG_ICASE is set, then we considers upper- and lowercase
-     versions of letters to be equivalent when matching.
-
-     If REG_NOSUB is set, then when PREG is passed to regexec, that
-     routine will report only success or failure, and nothing about the
-     registers.
-
-   It returns 0 if it succeeds, nonzero if it doesn't.  (See regex.h for
-   the return codes and their meanings.)  */
-
-int
-regcomp (preg, pattern, cflags)
-    regex_t *_Restrict_ preg;
-    const char *_Restrict_ pattern;
-    int cflags;
-{
-  reg_errcode_t ret;
-  reg_syntax_t syntax = ((cflags & REG_EXTENDED) ? RE_SYNTAX_POSIX_EXTENDED
-			 : RE_SYNTAX_POSIX_BASIC);
-
-  preg->buffer = NULL;
-  preg->allocated = 0;
-  preg->used = 0;
-
-  /* Try to allocate space for the fastmap.  */
-  preg->fastmap = re_malloc (char, SBC_MAX);
-  if (BE (preg->fastmap == NULL, 0))
-    return REG_ESPACE;
-
-  syntax |= (cflags & REG_ICASE) ? RE_ICASE : 0;
-
-  /* If REG_NEWLINE is set, newlines are treated differently.  */
-  if (cflags & REG_NEWLINE)
-    { /* REG_NEWLINE implies neither . nor [^...] match newline.  */
-      syntax &= ~RE_DOT_NEWLINE;
-      syntax |= RE_HAT_LISTS_NOT_NEWLINE;
-      /* It also changes the matching behavior.  */
-      preg->newline_anchor = 1;
-    }
-  else
-    preg->newline_anchor = 0;
-  preg->no_sub = !!(cflags & REG_NOSUB);
-  preg->translate = NULL;
-
-  ret = re_compile_internal (preg, pattern, strlen (pattern), syntax);
-
-  /* POSIX doesn't distinguish between an unmatched open-group and an
-     unmatched close-group: both are REG_EPAREN.  */
-  if (ret == REG_ERPAREN)
-    ret = REG_EPAREN;
-
-  /* We have already checked preg->fastmap != NULL.  */
-  if (BE (ret == REG_NOERROR, 1))
-    /* Compute the fastmap now, since regexec cannot modify the pattern
-       buffer.  This function never fails in this implementation.  */
-    (void) re_compile_fastmap (preg);
-  else
-    {
-      /* Some error occurred while compiling the expression.  */
-      re_free (preg->fastmap);
-      preg->fastmap = NULL;
-    }
-
-  return (int) ret;
-}
-#ifdef _LIBC
-weak_alias (__regcomp, regcomp)
-#endif
-
-/* Returns a message corresponding to an error code, ERRCODE, returned
-   from either regcomp or regexec.   We don't use PREG here.  */
-
-#ifdef _LIBC
-size_t
-regerror (errcode, preg, errbuf, errbuf_size)
-    int errcode;
-    const regex_t *_Restrict_ preg;
-    char *_Restrict_ errbuf;
-    size_t errbuf_size;
-#else /* size_t might promote */
-size_t
-regerror (int errcode, const regex_t *_Restrict_ preg,
-	  char *_Restrict_ errbuf, size_t errbuf_size)
-#endif
-{
-  const char *msg;
-  size_t msg_size;
-
-  if (BE (errcode < 0
-	  || errcode >= (int) (sizeof (__re_error_msgid_idx)
-			       / sizeof (__re_error_msgid_idx[0])), 0))
-    /* Only error codes returned by the rest of the code should be passed
-       to this routine.  If we are given anything else, or if other regex
-       code generates an invalid error code, then the program has a bug.
-       Dump core so we can fix it.  */
-    abort ();
-
-  msg = gettext (__re_error_msgid + __re_error_msgid_idx[errcode]);
-
-  msg_size = strlen (msg) + 1; /* Includes the null.  */
-
-  if (BE (errbuf_size != 0, 1))
-    {
-      size_t cpy_size = msg_size;
-      if (BE (msg_size > errbuf_size, 0))
-	{
-	  cpy_size = errbuf_size - 1;
-	  errbuf[cpy_size] = '\0';
-	}
-      memcpy (errbuf, msg, cpy_size);
-    }
-
-  return msg_size;
-}
-#ifdef _LIBC
-weak_alias (__regerror, regerror)
-#endif
-
-
-#ifdef RE_ENABLE_I18N
-/* This static array is used for the map to single-byte characters when
-   UTF-8 is used.  Otherwise we would allocate memory just to initialize
-   it the same all the time.  UTF-8 is the preferred encoding so this is
-   a worthwhile optimization.  */
-static const bitset_t utf8_sb_map =
-{
-  /* Set the first 128 bits.  */
-# if defined __GNUC__ && !defined __STRICT_ANSI__
-  [0 ... 0x80 / BITSET_WORD_BITS - 1] = BITSET_WORD_MAX
-# else
-#  if 4 * BITSET_WORD_BITS < ASCII_CHARS
-#   error "bitset_word_t is narrower than 32 bits"
-#  elif 3 * BITSET_WORD_BITS < ASCII_CHARS
-  BITSET_WORD_MAX, BITSET_WORD_MAX, BITSET_WORD_MAX,
-#  elif 2 * BITSET_WORD_BITS < ASCII_CHARS
-  BITSET_WORD_MAX, BITSET_WORD_MAX,
-#  elif 1 * BITSET_WORD_BITS < ASCII_CHARS
-  BITSET_WORD_MAX,
-#  endif
-  (BITSET_WORD_MAX
-   >> (SBC_MAX % BITSET_WORD_BITS == 0
-       ? 0
-       : BITSET_WORD_BITS - SBC_MAX % BITSET_WORD_BITS))
-# endif
-};
-#endif
-
-
-static void
-free_dfa_content (re_dfa_t *dfa)
-{
-  Idx i, j;
-
-  if (dfa->nodes)
-    for (i = 0; i < dfa->nodes_len; ++i)
-      free_token (dfa->nodes + i);
-  re_free (dfa->nexts);
-  for (i = 0; i < dfa->nodes_len; ++i)
-    {
-      if (dfa->eclosures != NULL)
-	re_node_set_free (dfa->eclosures + i);
-      if (dfa->inveclosures != NULL)
-	re_node_set_free (dfa->inveclosures + i);
-      if (dfa->edests != NULL)
-	re_node_set_free (dfa->edests + i);
-    }
-  re_free (dfa->edests);
-  re_free (dfa->eclosures);
-  re_free (dfa->inveclosures);
-  re_free (dfa->nodes);
-
-  if (dfa->state_table)
-    for (i = 0; i <= dfa->state_hash_mask; ++i)
-      {
-	struct re_state_table_entry *entry = dfa->state_table + i;
-	for (j = 0; j < entry->num; ++j)
-	  {
-	    re_dfastate_t *state = entry->array[j];
-	    free_state (state);
-	  }
-	re_free (entry->array);
-      }
-  re_free (dfa->state_table);
-#ifdef RE_ENABLE_I18N
-  if (dfa->sb_char != utf8_sb_map)
-    re_free (dfa->sb_char);
-#endif
-  re_free (dfa->subexp_map);
-#ifdef DEBUG
-  re_free (dfa->re_str);
-#endif
-
-  re_free (dfa);
-}
-
-
-/* Free dynamically allocated space used by PREG.  */
-
-void
-regfree (preg)
-    regex_t *preg;
-{
-  re_dfa_t *dfa = preg->buffer;
-  if (BE (dfa != NULL, 1))
-    {
-      lock_fini (dfa->lock);
-      free_dfa_content (dfa);
-    }
-  preg->buffer = NULL;
-  preg->allocated = 0;
-
-  re_free (preg->fastmap);
-  preg->fastmap = NULL;
-
-  re_free (preg->translate);
-  preg->translate = NULL;
-}
-#ifdef _LIBC
-weak_alias (__regfree, regfree)
-#endif
-
-/* Entry points compatible with 4.2 BSD regex library.  We don't define
-   them unless specifically requested.  */
-
-#if defined _REGEX_RE_COMP || defined _LIBC
-
-/* BSD has one and only one pattern buffer.  */
-static struct re_pattern_buffer re_comp_buf;
-
-char *
-# ifdef _LIBC
-/* Make these definitions weak in libc, so POSIX programs can redefine
-   these names if they don't use our functions, and still use
-   regcomp/regexec above without link errors.  */
-weak_function
-# endif
-re_comp (s)
-     const char *s;
-{
-  reg_errcode_t ret;
-  char *fastmap;
-
-  if (!s)
-    {
-      if (!re_comp_buf.buffer)
-	return gettext ("No previous regular expression");
-      return 0;
-    }
-
-  if (re_comp_buf.buffer)
-    {
-      fastmap = re_comp_buf.fastmap;
-      re_comp_buf.fastmap = NULL;
-      __regfree (&re_comp_buf);
-      memset (&re_comp_buf, '\0', sizeof (re_comp_buf));
-      re_comp_buf.fastmap = fastmap;
-    }
-
-  if (re_comp_buf.fastmap == NULL)
-    {
-      re_comp_buf.fastmap = (char *) malloc (SBC_MAX);
-      if (re_comp_buf.fastmap == NULL)
-	return (char *) gettext (__re_error_msgid
-				 + __re_error_msgid_idx[(int) REG_ESPACE]);
-    }
-
-  /* Since 're_exec' always passes NULL for the 'regs' argument, we
-     don't need to initialize the pattern buffer fields which affect it.  */
-
-  /* Match anchors at newlines.  */
-  re_comp_buf.newline_anchor = 1;
-
-  ret = re_compile_internal (&re_comp_buf, s, strlen (s), re_syntax_options);
-
-  if (!ret)
-    return NULL;
-
-  /* Yes, we're discarding 'const' here if !HAVE_LIBINTL.  */
-  return (char *) gettext (__re_error_msgid + __re_error_msgid_idx[(int) ret]);
-}
-
-#ifdef _LIBC
-libc_freeres_fn (free_mem)
-{
-  __regfree (&re_comp_buf);
-}
-#endif
-
-#endif /* _REGEX_RE_COMP */
-
-/* Internal entry point.
-   Compile the regular expression PATTERN, whose length is LENGTH.
-   SYNTAX indicate regular expression's syntax.  */
-
-static reg_errcode_t
-re_compile_internal (regex_t *preg, const char * pattern, size_t length,
-		     reg_syntax_t syntax)
-{
-  reg_errcode_t err = REG_NOERROR;
-  re_dfa_t *dfa;
-  re_string_t regexp;
-
-  /* Initialize the pattern buffer.  */
-  preg->fastmap_accurate = 0;
-  preg->syntax = syntax;
-  preg->not_bol = preg->not_eol = 0;
-  preg->used = 0;
-  preg->re_nsub = 0;
-  preg->can_be_null = 0;
-  preg->regs_allocated = REGS_UNALLOCATED;
-
-  /* Initialize the dfa.  */
-  dfa = preg->buffer;
-  if (BE (preg->allocated < sizeof (re_dfa_t), 0))
-    {
-      /* If zero allocated, but buffer is non-null, try to realloc
-	 enough space.  This loses if buffer's address is bogus, but
-	 that is the user's responsibility.  If ->buffer is NULL this
-	 is a simple allocation.  */
-      dfa = re_realloc (preg->buffer, re_dfa_t, 1);
-      if (dfa == NULL)
-	return REG_ESPACE;
-      preg->allocated = sizeof (re_dfa_t);
-      preg->buffer = dfa;
-    }
-  preg->used = sizeof (re_dfa_t);
-
-  err = init_dfa (dfa, length);
-  if (BE (err == REG_NOERROR && lock_init (dfa->lock) != 0, 0))
-    err = REG_ESPACE;
-  if (BE (err != REG_NOERROR, 0))
-    {
-      free_dfa_content (dfa);
-      preg->buffer = NULL;
-      preg->allocated = 0;
-      return err;
-    }
-#ifdef DEBUG
-  /* Note: length+1 will not overflow since it is checked in init_dfa.  */
-  dfa->re_str = re_malloc (char, length + 1);
-  strncpy (dfa->re_str, pattern, length + 1);
-#endif
-
-  err = re_string_construct (&regexp, pattern, length, preg->translate,
-			     (syntax & RE_ICASE) != 0, dfa);
-  if (BE (err != REG_NOERROR, 0))
-    {
-    re_compile_internal_free_return:
-      free_workarea_compile (preg);
-      re_string_destruct (&regexp);
-      lock_fini (dfa->lock);
-      free_dfa_content (dfa);
-      preg->buffer = NULL;
-      preg->allocated = 0;
-      return err;
-    }
-
-  /* Parse the regular expression, and build a structure tree.  */
-  preg->re_nsub = 0;
-  dfa->str_tree = parse (&regexp, preg, syntax, &err);
-  if (BE (dfa->str_tree == NULL, 0))
-    goto re_compile_internal_free_return;
-
-  /* Analyze the tree and create the nfa.  */
-  err = analyze (preg);
-  if (BE (err != REG_NOERROR, 0))
-    goto re_compile_internal_free_return;
-
-#ifdef RE_ENABLE_I18N
-  /* If possible, do searching in single byte encoding to speed things up.  */
-  if (dfa->is_utf8 && !(syntax & RE_ICASE) && preg->translate == NULL)
-    optimize_utf8 (dfa);
-#endif
-
-  /* Then create the initial state of the dfa.  */
-  err = create_initial_state (dfa);
-
-  /* Release work areas.  */
-  free_workarea_compile (preg);
-  re_string_destruct (&regexp);
-
-  if (BE (err != REG_NOERROR, 0))
-    {
-      lock_fini (dfa->lock);
-      free_dfa_content (dfa);
-      preg->buffer = NULL;
-      preg->allocated = 0;
-    }
-
-  return err;
-}
-
-/* Initialize DFA.  We use the length of the regular expression PAT_LEN
-   as the initial length of some arrays.  */
-
-static reg_errcode_t
-init_dfa (re_dfa_t *dfa, size_t pat_len)
-{
-  __re_size_t table_size;
-#ifndef _LIBC
-  const char *codeset_name;
-#endif
-#ifdef RE_ENABLE_I18N
-  size_t max_i18n_object_size = MAX (sizeof (wchar_t), sizeof (wctype_t));
-#else
-  size_t max_i18n_object_size = 0;
-#endif
-  size_t max_object_size =
-    MAX (sizeof (struct re_state_table_entry),
-	 MAX (sizeof (re_token_t),
-	      MAX (sizeof (re_node_set),
-		   MAX (sizeof (regmatch_t),
-			max_i18n_object_size))));
-
-  memset (dfa, '\0', sizeof (re_dfa_t));
-
-  /* Force allocation of str_tree_storage the first time.  */
-  dfa->str_tree_storage_idx = BIN_TREE_STORAGE_SIZE;
-
-  /* Avoid overflows.  The extra "/ 2" is for the table_size doubling
-     calculation below, and for similar doubling calculations
-     elsewhere.  And it's <= rather than <, because some of the
-     doubling calculations add 1 afterwards.  */
-  if (BE (MIN (IDX_MAX, SIZE_MAX / max_object_size) / 2 <= pat_len, 0))
-    return REG_ESPACE;
-
-  dfa->nodes_alloc = pat_len + 1;
-  dfa->nodes = re_malloc (re_token_t, dfa->nodes_alloc);
-
-  /*  table_size = 2 ^ ceil(log pat_len) */
-  for (table_size = 1; ; table_size <<= 1)
-    if (table_size > pat_len)
-      break;
-
-  dfa->state_table = calloc (sizeof (struct re_state_table_entry), table_size);
-  dfa->state_hash_mask = table_size - 1;
-
-  dfa->mb_cur_max = MB_CUR_MAX;
-#ifdef _LIBC
-  if (dfa->mb_cur_max == 6
-      && strcmp (_NL_CURRENT (LC_CTYPE, _NL_CTYPE_CODESET_NAME), "UTF-8") == 0)
-    dfa->is_utf8 = 1;
-  dfa->map_notascii = (_NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_MAP_TO_NONASCII)
-		       != 0);
-#else
-  codeset_name = nl_langinfo (CODESET);
-  if ((codeset_name[0] == 'U' || codeset_name[0] == 'u')
-      && (codeset_name[1] == 'T' || codeset_name[1] == 't')
-      && (codeset_name[2] == 'F' || codeset_name[2] == 'f')
-      && strcmp (codeset_name + 3 + (codeset_name[3] == '-'), "8") == 0)
-    dfa->is_utf8 = 1;
-
-  /* We check exhaustively in the loop below if this charset is a
-     superset of ASCII.  */
-  dfa->map_notascii = 0;
-#endif
-
-#ifdef RE_ENABLE_I18N
-  if (dfa->mb_cur_max > 1)
-    {
-      if (dfa->is_utf8)
-	dfa->sb_char = (re_bitset_ptr_t) utf8_sb_map;
-      else
-	{
-	  int i, j, ch;
-
-	  dfa->sb_char = (re_bitset_ptr_t) calloc (sizeof (bitset_t), 1);
-	  if (BE (dfa->sb_char == NULL, 0))
-	    return REG_ESPACE;
-
-	  /* Set the bits corresponding to single byte chars.  */
-	  for (i = 0, ch = 0; i < BITSET_WORDS; ++i)
-	    for (j = 0; j < BITSET_WORD_BITS; ++j, ++ch)
-	      {
-		wint_t wch = __btowc (ch);
-		if (wch != WEOF)
-		  dfa->sb_char[i] |= (bitset_word_t) 1 << j;
-# ifndef _LIBC
-		if (isascii (ch) && wch != ch)
-		  dfa->map_notascii = 1;
-# endif
-	      }
-	}
-    }
-#endif
-
-  if (BE (dfa->nodes == NULL || dfa->state_table == NULL, 0))
-    return REG_ESPACE;
-  return REG_NOERROR;
-}
-
-/* Initialize WORD_CHAR table, which indicate which character is
-   "word".  In this case "word" means that it is the word construction
-   character used by some operators like "\<", "\>", etc.  */
-
-static void
-internal_function
-init_word_char (re_dfa_t *dfa)
-{
-  int i = 0;
-  int j;
-  int ch = 0;
-  dfa->word_ops_used = 1;
-  if (BE (dfa->map_notascii == 0, 1))
-    {
-      bitset_word_t bits0 = 0x00000000;
-      bitset_word_t bits1 = 0x03ff0000;
-      bitset_word_t bits2 = 0x87fffffe;
-      bitset_word_t bits3 = 0x07fffffe;
-      if (BITSET_WORD_BITS == 64)
-	{
-	  dfa->word_char[0] = bits1 << 31 << 1 | bits0;
-	  dfa->word_char[1] = bits3 << 31 << 1 | bits2;
-	  i = 2;
-	}
-      else if (BITSET_WORD_BITS == 32)
-	{
-	  dfa->word_char[0] = bits0;
-	  dfa->word_char[1] = bits1;
-	  dfa->word_char[2] = bits2;
-	  dfa->word_char[3] = bits3;
-	  i = 4;
-	}
-      else
-        goto general_case;
-      ch = 128;
-
-      if (BE (dfa->is_utf8, 1))
-	{
-	  memset (&dfa->word_char[i], '\0', (SBC_MAX - ch) / 8);
-	  return;
-	}
-    }
-
- general_case:
-  for (; i < BITSET_WORDS; ++i)
-    for (j = 0; j < BITSET_WORD_BITS; ++j, ++ch)
-      if (isalnum (ch) || ch == '_')
-	dfa->word_char[i] |= (bitset_word_t) 1 << j;
-}
-
-/* Free the work area which are only used while compiling.  */
-
-static void
-free_workarea_compile (regex_t *preg)
-{
-  re_dfa_t *dfa = preg->buffer;
-  bin_tree_storage_t *storage, *next;
-  for (storage = dfa->str_tree_storage; storage; storage = next)
-    {
-      next = storage->next;
-      re_free (storage);
-    }
-  dfa->str_tree_storage = NULL;
-  dfa->str_tree_storage_idx = BIN_TREE_STORAGE_SIZE;
-  dfa->str_tree = NULL;
-  re_free (dfa->org_indices);
-  dfa->org_indices = NULL;
-}
-
-/* Create initial states for all contexts.  */
-
-static reg_errcode_t
-create_initial_state (re_dfa_t *dfa)
-{
-  Idx first, i;
-  reg_errcode_t err;
-  re_node_set init_nodes;
-
-  /* Initial states have the epsilon closure of the node which is
-     the first node of the regular expression.  */
-  first = dfa->str_tree->first->node_idx;
-  dfa->init_node = first;
-  err = re_node_set_init_copy (&init_nodes, dfa->eclosures + first);
-  if (BE (err != REG_NOERROR, 0))
-    return err;
-
-  /* The back-references which are in initial states can epsilon transit,
-     since in this case all of the subexpressions can be null.
-     Then we add epsilon closures of the nodes which are the next nodes of
-     the back-references.  */
-  if (dfa->nbackref > 0)
-    for (i = 0; i < init_nodes.nelem; ++i)
-      {
-	Idx node_idx = init_nodes.elems[i];
-	re_token_type_t type = dfa->nodes[node_idx].type;
-
-	Idx clexp_idx;
-	if (type != OP_BACK_REF)
-	  continue;
-	for (clexp_idx = 0; clexp_idx < init_nodes.nelem; ++clexp_idx)
-	  {
-	    re_token_t *clexp_node;
-	    clexp_node = dfa->nodes + init_nodes.elems[clexp_idx];
-	    if (clexp_node->type == OP_CLOSE_SUBEXP
-		&& clexp_node->opr.idx == dfa->nodes[node_idx].opr.idx)
-	      break;
-	  }
-	if (clexp_idx == init_nodes.nelem)
-	  continue;
-
-	if (type == OP_BACK_REF)
-	  {
-	    Idx dest_idx = dfa->edests[node_idx].elems[0];
-	    if (!re_node_set_contains (&init_nodes, dest_idx))
-	      {
-		reg_errcode_t merge_err
-                  = re_node_set_merge (&init_nodes, dfa->eclosures + dest_idx);
-		if (merge_err != REG_NOERROR)
-		  return merge_err;
-		i = 0;
-	      }
-	  }
-      }
-
-  /* It must be the first time to invoke acquire_state.  */
-  dfa->init_state = re_acquire_state_context (&err, dfa, &init_nodes, 0);
-  /* We don't check ERR here, since the initial state must not be NULL.  */
-  if (BE (dfa->init_state == NULL, 0))
-    return err;
-  if (dfa->init_state->has_constraint)
-    {
-      dfa->init_state_word = re_acquire_state_context (&err, dfa, &init_nodes,
-						       CONTEXT_WORD);
-      dfa->init_state_nl = re_acquire_state_context (&err, dfa, &init_nodes,
-						     CONTEXT_NEWLINE);
-      dfa->init_state_begbuf = re_acquire_state_context (&err, dfa,
-							 &init_nodes,
-							 CONTEXT_NEWLINE
-							 | CONTEXT_BEGBUF);
-      if (BE (dfa->init_state_word == NULL || dfa->init_state_nl == NULL
-	      || dfa->init_state_begbuf == NULL, 0))
-	return err;
-    }
-  else
-    dfa->init_state_word = dfa->init_state_nl
-      = dfa->init_state_begbuf = dfa->init_state;
-
-  re_node_set_free (&init_nodes);
-  return REG_NOERROR;
-}
-
-#ifdef RE_ENABLE_I18N
-/* If it is possible to do searching in single byte encoding instead of UTF-8
-   to speed things up, set dfa->mb_cur_max to 1, clear is_utf8 and change
-   DFA nodes where needed.  */
-
-static void
-optimize_utf8 (re_dfa_t *dfa)
-{
-  Idx node;
-  int i;
-  bool mb_chars = false;
-  bool has_period = false;
-
-  for (node = 0; node < dfa->nodes_len; ++node)
-    switch (dfa->nodes[node].type)
-      {
-      case CHARACTER:
-	if (dfa->nodes[node].opr.c >= ASCII_CHARS)
-	  mb_chars = true;
-	break;
-      case ANCHOR:
-	switch (dfa->nodes[node].opr.ctx_type)
-	  {
-	  case LINE_FIRST:
-	  case LINE_LAST:
-	  case BUF_FIRST:
-	  case BUF_LAST:
-	    break;
-	  default:
-	    /* Word anchors etc. cannot be handled.  It's okay to test
-	       opr.ctx_type since constraints (for all DFA nodes) are
-	       created by ORing one or more opr.ctx_type values.  */
-	    return;
-	  }
-	break;
-      case OP_PERIOD:
-	has_period = true;
-	break;
-      case OP_BACK_REF:
-      case OP_ALT:
-      case END_OF_RE:
-      case OP_DUP_ASTERISK:
-      case OP_OPEN_SUBEXP:
-      case OP_CLOSE_SUBEXP:
-	break;
-      case COMPLEX_BRACKET:
-	return;
-      case SIMPLE_BRACKET:
-	/* Just double check.  */
-	{
-	  int rshift = (ASCII_CHARS % BITSET_WORD_BITS == 0
-			? 0
-			: BITSET_WORD_BITS - ASCII_CHARS % BITSET_WORD_BITS);
-	  for (i = ASCII_CHARS / BITSET_WORD_BITS; i < BITSET_WORDS; ++i)
-	    {
-	      if (dfa->nodes[node].opr.sbcset[i] >> rshift != 0)
-		return;
-	      rshift = 0;
-	    }
-	}
-	break;
-      default:
-	abort ();
-      }
-
-  if (mb_chars || has_period)
-    for (node = 0; node < dfa->nodes_len; ++node)
-      {
-	if (dfa->nodes[node].type == CHARACTER
-	    && dfa->nodes[node].opr.c >= ASCII_CHARS)
-	  dfa->nodes[node].mb_partial = 0;
-	else if (dfa->nodes[node].type == OP_PERIOD)
-	  dfa->nodes[node].type = OP_UTF8_PERIOD;
-      }
-
-  /* The search can be in single byte locale.  */
-  dfa->mb_cur_max = 1;
-  dfa->is_utf8 = 0;
-  dfa->has_mb_node = dfa->nbackref > 0 || has_period;
-}
-#endif
-
-/* Analyze the structure tree, and calculate "first", "next", "edest",
-   "eclosure", and "inveclosure".  */
-
-static reg_errcode_t
-analyze (regex_t *preg)
-{
-  re_dfa_t *dfa = preg->buffer;
-  reg_errcode_t ret;
-
-  /* Allocate arrays.  */
-  dfa->nexts = re_malloc (Idx, dfa->nodes_alloc);
-  dfa->org_indices = re_malloc (Idx, dfa->nodes_alloc);
-  dfa->edests = re_malloc (re_node_set, dfa->nodes_alloc);
-  dfa->eclosures = re_malloc (re_node_set, dfa->nodes_alloc);
-  if (BE (dfa->nexts == NULL || dfa->org_indices == NULL || dfa->edests == NULL
-	  || dfa->eclosures == NULL, 0))
-    return REG_ESPACE;
-
-  dfa->subexp_map = re_malloc (Idx, preg->re_nsub);
-  if (dfa->subexp_map != NULL)
-    {
-      Idx i;
-      for (i = 0; i < preg->re_nsub; i++)
-	dfa->subexp_map[i] = i;
-      preorder (dfa->str_tree, optimize_subexps, dfa);
-      for (i = 0; i < preg->re_nsub; i++)
-	if (dfa->subexp_map[i] != i)
-	  break;
-      if (i == preg->re_nsub)
-	{
-	  free (dfa->subexp_map);
-	  dfa->subexp_map = NULL;
-	}
-    }
-
-  ret = postorder (dfa->str_tree, lower_subexps, preg);
-  if (BE (ret != REG_NOERROR, 0))
-    return ret;
-  ret = postorder (dfa->str_tree, calc_first, dfa);
-  if (BE (ret != REG_NOERROR, 0))
-    return ret;
-  preorder (dfa->str_tree, calc_next, dfa);
-  ret = preorder (dfa->str_tree, link_nfa_nodes, dfa);
-  if (BE (ret != REG_NOERROR, 0))
-    return ret;
-  ret = calc_eclosure (dfa);
-  if (BE (ret != REG_NOERROR, 0))
-    return ret;
-
-  /* We only need this during the prune_impossible_nodes pass in regexec.c;
-     skip it if p_i_n will not run, as calc_inveclosure can be quadratic.  */
-  if ((!preg->no_sub && preg->re_nsub > 0 && dfa->has_plural_match)
-      || dfa->nbackref)
-    {
-      dfa->inveclosures = re_malloc (re_node_set, dfa->nodes_len);
-      if (BE (dfa->inveclosures == NULL, 0))
-	return REG_ESPACE;
-      ret = calc_inveclosure (dfa);
-    }
-
-  return ret;
-}
-
-/* Our parse trees are very unbalanced, so we cannot use a stack to
-   implement parse tree visits.  Instead, we use parent pointers and
-   some hairy code in these two functions.  */
-static reg_errcode_t
-postorder (bin_tree_t *root, reg_errcode_t (fn (void *, bin_tree_t *)),
-	   void *extra)
-{
-  bin_tree_t *node, *prev;
-
-  for (node = root; ; )
-    {
-      /* Descend down the tree, preferably to the left (or to the right
-	 if that's the only child).  */
-      while (node->left || node->right)
-	if (node->left)
-	  node = node->left;
-	else
-	  node = node->right;
-
-      do
-	{
-	  reg_errcode_t err = fn (extra, node);
-	  if (BE (err != REG_NOERROR, 0))
-	    return err;
-	  if (node->parent == NULL)
-	    return REG_NOERROR;
-	  prev = node;
-	  node = node->parent;
-	}
-      /* Go up while we have a node that is reached from the right.  */
-      while (node->right == prev || node->right == NULL);
-      node = node->right;
-    }
-}
-
-static reg_errcode_t
-preorder (bin_tree_t *root, reg_errcode_t (fn (void *, bin_tree_t *)),
-	  void *extra)
-{
-  bin_tree_t *node;
-
-  for (node = root; ; )
-    {
-      reg_errcode_t err = fn (extra, node);
-      if (BE (err != REG_NOERROR, 0))
-	return err;
-
-      /* Go to the left node, or up and to the right.  */
-      if (node->left)
-	node = node->left;
-      else
-	{
-	  bin_tree_t *prev = NULL;
-	  while (node->right == prev || node->right == NULL)
-	    {
-	      prev = node;
-	      node = node->parent;
-	      if (!node)
-		return REG_NOERROR;
-	    }
-	  node = node->right;
-	}
-    }
-}
-
-/* Optimization pass: if a SUBEXP is entirely contained, strip it and tell
-   re_search_internal to map the inner one's opr.idx to this one's.  Adjust
-   backreferences as well.  Requires a preorder visit.  */
-static reg_errcode_t
-optimize_subexps (void *extra, bin_tree_t *node)
-{
-  re_dfa_t *dfa = (re_dfa_t *) extra;
-
-  if (node->token.type == OP_BACK_REF && dfa->subexp_map)
-    {
-      int idx = node->token.opr.idx;
-      node->token.opr.idx = dfa->subexp_map[idx];
-      dfa->used_bkref_map |= 1 << node->token.opr.idx;
-    }
-
-  else if (node->token.type == SUBEXP
-	   && node->left && node->left->token.type == SUBEXP)
-    {
-      Idx other_idx = node->left->token.opr.idx;
-
-      node->left = node->left->left;
-      if (node->left)
-	node->left->parent = node;
-
-      dfa->subexp_map[other_idx] = dfa->subexp_map[node->token.opr.idx];
-      if (other_idx < BITSET_WORD_BITS)
-	dfa->used_bkref_map &= ~((bitset_word_t) 1 << other_idx);
-    }
-
-  return REG_NOERROR;
-}
-
-/* Lowering pass: Turn each SUBEXP node into the appropriate concatenation
-   of OP_OPEN_SUBEXP, the body of the SUBEXP (if any) and OP_CLOSE_SUBEXP.  */
-static reg_errcode_t
-lower_subexps (void *extra, bin_tree_t *node)
-{
-  regex_t *preg = (regex_t *) extra;
-  reg_errcode_t err = REG_NOERROR;
-
-  if (node->left && node->left->token.type == SUBEXP)
-    {
-      node->left = lower_subexp (&err, preg, node->left);
-      if (node->left)
-	node->left->parent = node;
-    }
-  if (node->right && node->right->token.type == SUBEXP)
-    {
-      node->right = lower_subexp (&err, preg, node->right);
-      if (node->right)
-	node->right->parent = node;
-    }
-
-  return err;
-}
-
-static bin_tree_t *
-lower_subexp (reg_errcode_t *err, regex_t *preg, bin_tree_t *node)
-{
-  re_dfa_t *dfa = preg->buffer;
-  bin_tree_t *body = node->left;
-  bin_tree_t *op, *cls, *tree1, *tree;
-
-  if (preg->no_sub
-      /* We do not optimize empty subexpressions, because otherwise we may
-	 have bad CONCAT nodes with NULL children.  This is obviously not
-	 very common, so we do not lose much.  An example that triggers
-	 this case is the sed "script" /\(\)/x.  */
-      && node->left != NULL
-      && (node->token.opr.idx >= BITSET_WORD_BITS
-	  || !(dfa->used_bkref_map
-	       & ((bitset_word_t) 1 << node->token.opr.idx))))
-    return node->left;
-
-  /* Convert the SUBEXP node to the concatenation of an
-     OP_OPEN_SUBEXP, the contents, and an OP_CLOSE_SUBEXP.  */
-  op = create_tree (dfa, NULL, NULL, OP_OPEN_SUBEXP);
-  cls = create_tree (dfa, NULL, NULL, OP_CLOSE_SUBEXP);
-  tree1 = body ? create_tree (dfa, body, cls, CONCAT) : cls;
-  tree = create_tree (dfa, op, tree1, CONCAT);
-  if (BE (tree == NULL || tree1 == NULL || op == NULL || cls == NULL, 0))
-    {
-      *err = REG_ESPACE;
-      return NULL;
-    }
-
-  op->token.opr.idx = cls->token.opr.idx = node->token.opr.idx;
-  op->token.opt_subexp = cls->token.opt_subexp = node->token.opt_subexp;
-  return tree;
-}
-
-/* Pass 1 in building the NFA: compute FIRST and create unlinked automaton
-   nodes.  Requires a postorder visit.  */
-static reg_errcode_t
-calc_first (void *extra, bin_tree_t *node)
-{
-  re_dfa_t *dfa = (re_dfa_t *) extra;
-  if (node->token.type == CONCAT)
-    {
-      node->first = node->left->first;
-      node->node_idx = node->left->node_idx;
-    }
-  else
-    {
-      node->first = node;
-      node->node_idx = re_dfa_add_node (dfa, node->token);
-      if (BE (node->node_idx == REG_MISSING, 0))
-	return REG_ESPACE;
-      if (node->token.type == ANCHOR)
-	dfa->nodes[node->node_idx].constraint = node->token.opr.ctx_type;
-    }
-  return REG_NOERROR;
-}
-
-/* Pass 2: compute NEXT on the tree.  Preorder visit.  */
-static reg_errcode_t
-calc_next (void *extra, bin_tree_t *node)
-{
-  switch (node->token.type)
-    {
-    case OP_DUP_ASTERISK:
-      node->left->next = node;
-      break;
-    case CONCAT:
-      node->left->next = node->right->first;
-      node->right->next = node->next;
-      break;
-    default:
-      if (node->left)
-	node->left->next = node->next;
-      if (node->right)
-	node->right->next = node->next;
-      break;
-    }
-  return REG_NOERROR;
-}
-
-/* Pass 3: link all DFA nodes to their NEXT node (any order will do).  */
-static reg_errcode_t
-link_nfa_nodes (void *extra, bin_tree_t *node)
-{
-  re_dfa_t *dfa = (re_dfa_t *) extra;
-  Idx idx = node->node_idx;
-  reg_errcode_t err = REG_NOERROR;
-
-  switch (node->token.type)
-    {
-    case CONCAT:
-      break;
-
-    case END_OF_RE:
-      assert (node->next == NULL);
-      break;
-
-    case OP_DUP_ASTERISK:
-    case OP_ALT:
-      {
-	Idx left, right;
-	dfa->has_plural_match = 1;
-	if (node->left != NULL)
-	  left = node->left->first->node_idx;
-	else
-	  left = node->next->node_idx;
-	if (node->right != NULL)
-	  right = node->right->first->node_idx;
-	else
-	  right = node->next->node_idx;
-	assert (REG_VALID_INDEX (left));
-	assert (REG_VALID_INDEX (right));
-	err = re_node_set_init_2 (dfa->edests + idx, left, right);
-      }
-      break;
-
-    case ANCHOR:
-    case OP_OPEN_SUBEXP:
-    case OP_CLOSE_SUBEXP:
-      err = re_node_set_init_1 (dfa->edests + idx, node->next->node_idx);
-      break;
-
-    case OP_BACK_REF:
-      dfa->nexts[idx] = node->next->node_idx;
-      if (node->token.type == OP_BACK_REF)
-	err = re_node_set_init_1 (dfa->edests + idx, dfa->nexts[idx]);
-      break;
-
-    default:
-      assert (!IS_EPSILON_NODE (node->token.type));
-      dfa->nexts[idx] = node->next->node_idx;
-      break;
-    }
-
-  return err;
-}
-
-/* Duplicate the epsilon closure of the node ROOT_NODE.
-   Note that duplicated nodes have constraint INIT_CONSTRAINT in addition
-   to their own constraint.  */
-
-static reg_errcode_t
-internal_function
-duplicate_node_closure (re_dfa_t *dfa, Idx top_org_node, Idx top_clone_node,
-			Idx root_node, unsigned int init_constraint)
-{
-  Idx org_node, clone_node;
-  bool ok;
-  unsigned int constraint = init_constraint;
-  for (org_node = top_org_node, clone_node = top_clone_node;;)
-    {
-      Idx org_dest, clone_dest;
-      if (dfa->nodes[org_node].type == OP_BACK_REF)
-	{
-	  /* If the back reference epsilon-transit, its destination must
-	     also have the constraint.  Then duplicate the epsilon closure
-	     of the destination of the back reference, and store it in
-	     edests of the back reference.  */
-	  org_dest = dfa->nexts[org_node];
-	  re_node_set_empty (dfa->edests + clone_node);
-	  clone_dest = duplicate_node (dfa, org_dest, constraint);
-	  if (BE (clone_dest == REG_MISSING, 0))
-	    return REG_ESPACE;
-	  dfa->nexts[clone_node] = dfa->nexts[org_node];
-	  ok = re_node_set_insert (dfa->edests + clone_node, clone_dest);
-	  if (BE (! ok, 0))
-	    return REG_ESPACE;
-	}
-      else if (dfa->edests[org_node].nelem == 0)
-	{
-	  /* In case of the node can't epsilon-transit, don't duplicate the
-	     destination and store the original destination as the
-	     destination of the node.  */
-	  dfa->nexts[clone_node] = dfa->nexts[org_node];
-	  break;
-	}
-      else if (dfa->edests[org_node].nelem == 1)
-	{
-	  /* In case of the node can epsilon-transit, and it has only one
-	     destination.  */
-	  org_dest = dfa->edests[org_node].elems[0];
-	  re_node_set_empty (dfa->edests + clone_node);
-	  /* If the node is root_node itself, it means the epsilon closure
-	     has a loop.  Then tie it to the destination of the root_node.  */
-	  if (org_node == root_node && clone_node != org_node)
-	    {
-	      ok = re_node_set_insert (dfa->edests + clone_node, org_dest);
-	      if (BE (! ok, 0))
-	        return REG_ESPACE;
-	      break;
-	    }
-	  /* In case the node has another constraint, append it.  */
-	  constraint |= dfa->nodes[org_node].constraint;
-	  clone_dest = duplicate_node (dfa, org_dest, constraint);
-	  if (BE (clone_dest == REG_MISSING, 0))
-	    return REG_ESPACE;
-	  ok = re_node_set_insert (dfa->edests + clone_node, clone_dest);
-	  if (BE (! ok, 0))
-	    return REG_ESPACE;
-	}
-      else /* dfa->edests[org_node].nelem == 2 */
-	{
-	  /* In case of the node can epsilon-transit, and it has two
-	     destinations. In the bin_tree_t and DFA, that's '|' and '*'.   */
-	  org_dest = dfa->edests[org_node].elems[0];
-	  re_node_set_empty (dfa->edests + clone_node);
-	  /* Search for a duplicated node which satisfies the constraint.  */
-	  clone_dest = search_duplicated_node (dfa, org_dest, constraint);
-	  if (clone_dest == REG_MISSING)
-	    {
-	      /* There is no such duplicated node, create a new one.  */
-	      reg_errcode_t err;
-	      clone_dest = duplicate_node (dfa, org_dest, constraint);
-	      if (BE (clone_dest == REG_MISSING, 0))
-		return REG_ESPACE;
-	      ok = re_node_set_insert (dfa->edests + clone_node, clone_dest);
-	      if (BE (! ok, 0))
-		return REG_ESPACE;
-	      err = duplicate_node_closure (dfa, org_dest, clone_dest,
-					    root_node, constraint);
-	      if (BE (err != REG_NOERROR, 0))
-		return err;
-	    }
-	  else
-	    {
-	      /* There is a duplicated node which satisfies the constraint,
-		 use it to avoid infinite loop.  */
-	      ok = re_node_set_insert (dfa->edests + clone_node, clone_dest);
-	      if (BE (! ok, 0))
-		return REG_ESPACE;
-	    }
-
-	  org_dest = dfa->edests[org_node].elems[1];
-	  clone_dest = duplicate_node (dfa, org_dest, constraint);
-	  if (BE (clone_dest == REG_MISSING, 0))
-	    return REG_ESPACE;
-	  ok = re_node_set_insert (dfa->edests + clone_node, clone_dest);
-	  if (BE (! ok, 0))
-	    return REG_ESPACE;
-	}
-      org_node = org_dest;
-      clone_node = clone_dest;
-    }
-  return REG_NOERROR;
-}
-
-/* Search for a node which is duplicated from the node ORG_NODE, and
-   satisfies the constraint CONSTRAINT.  */
-
-static Idx
-search_duplicated_node (const re_dfa_t *dfa, Idx org_node,
-			unsigned int constraint)
-{
-  Idx idx;
-  for (idx = dfa->nodes_len - 1; dfa->nodes[idx].duplicated && idx > 0; --idx)
-    {
-      if (org_node == dfa->org_indices[idx]
-	  && constraint == dfa->nodes[idx].constraint)
-	return idx; /* Found.  */
-    }
-  return REG_MISSING; /* Not found.  */
-}
-
-/* Duplicate the node whose index is ORG_IDX and set the constraint CONSTRAINT.
-   Return the index of the new node, or REG_MISSING if insufficient storage is
-   available.  */
-
-static Idx
-duplicate_node (re_dfa_t *dfa, Idx org_idx, unsigned int constraint)
-{
-  Idx dup_idx = re_dfa_add_node (dfa, dfa->nodes[org_idx]);
-  if (BE (dup_idx != REG_MISSING, 1))
-    {
-      dfa->nodes[dup_idx].constraint = constraint;
-      dfa->nodes[dup_idx].constraint |= dfa->nodes[org_idx].constraint;
-      dfa->nodes[dup_idx].duplicated = 1;
-
-      /* Store the index of the original node.  */
-      dfa->org_indices[dup_idx] = org_idx;
-    }
-  return dup_idx;
-}
-
-static reg_errcode_t
-calc_inveclosure (re_dfa_t *dfa)
-{
-  Idx src, idx;
-  bool ok;
-  for (idx = 0; idx < dfa->nodes_len; ++idx)
-    re_node_set_init_empty (dfa->inveclosures + idx);
-
-  for (src = 0; src < dfa->nodes_len; ++src)
-    {
-      Idx *elems = dfa->eclosures[src].elems;
-      for (idx = 0; idx < dfa->eclosures[src].nelem; ++idx)
-	{
-	  ok = re_node_set_insert_last (dfa->inveclosures + elems[idx], src);
-	  if (BE (! ok, 0))
-	    return REG_ESPACE;
-	}
-    }
-
-  return REG_NOERROR;
-}
-
-/* Calculate "eclosure" for all the node in DFA.  */
-
-static reg_errcode_t
-calc_eclosure (re_dfa_t *dfa)
-{
-  Idx node_idx;
-  bool incomplete;
-#ifdef DEBUG
-  assert (dfa->nodes_len > 0);
-#endif
-  incomplete = false;
-  /* For each nodes, calculate epsilon closure.  */
-  for (node_idx = 0; ; ++node_idx)
-    {
-      reg_errcode_t err;
-      re_node_set eclosure_elem;
-      if (node_idx == dfa->nodes_len)
-	{
-	  if (!incomplete)
-	    break;
-	  incomplete = false;
-	  node_idx = 0;
-	}
-
-#ifdef DEBUG
-      assert (dfa->eclosures[node_idx].nelem != REG_MISSING);
-#endif
-
-      /* If we have already calculated, skip it.  */
-      if (dfa->eclosures[node_idx].nelem != 0)
-	continue;
-      /* Calculate epsilon closure of 'node_idx'.  */
-      err = calc_eclosure_iter (&eclosure_elem, dfa, node_idx, true);
-      if (BE (err != REG_NOERROR, 0))
-	return err;
-
-      if (dfa->eclosures[node_idx].nelem == 0)
-	{
-	  incomplete = true;
-	  re_node_set_free (&eclosure_elem);
-	}
-    }
-  return REG_NOERROR;
-}
-
-/* Calculate epsilon closure of NODE.  */
-
-static reg_errcode_t
-calc_eclosure_iter (re_node_set *new_set, re_dfa_t *dfa, Idx node, bool root)
-{
-  reg_errcode_t err;
-  Idx i;
-  re_node_set eclosure;
-  bool ok;
-  bool incomplete = false;
-  err = re_node_set_alloc (&eclosure, dfa->edests[node].nelem + 1);
-  if (BE (err != REG_NOERROR, 0))
-    return err;
-
-  /* This indicates that we are calculating this node now.
-     We reference this value to avoid infinite loop.  */
-  dfa->eclosures[node].nelem = REG_MISSING;
-
-  /* If the current node has constraints, duplicate all nodes
-     since they must inherit the constraints.  */
-  if (dfa->nodes[node].constraint
-      && dfa->edests[node].nelem
-      && !dfa->nodes[dfa->edests[node].elems[0]].duplicated)
-    {
-      err = duplicate_node_closure (dfa, node, node, node,
-				    dfa->nodes[node].constraint);
-      if (BE (err != REG_NOERROR, 0))
-	return err;
-    }
-
-  /* Expand each epsilon destination nodes.  */
-  if (IS_EPSILON_NODE(dfa->nodes[node].type))
-    for (i = 0; i < dfa->edests[node].nelem; ++i)
-      {
-	re_node_set eclosure_elem;
-	Idx edest = dfa->edests[node].elems[i];
-	/* If calculating the epsilon closure of 'edest' is in progress,
-	   return intermediate result.  */
-	if (dfa->eclosures[edest].nelem == REG_MISSING)
-	  {
-	    incomplete = true;
-	    continue;
-	  }
-	/* If we haven't calculated the epsilon closure of 'edest' yet,
-	   calculate now. Otherwise use calculated epsilon closure.  */
-	if (dfa->eclosures[edest].nelem == 0)
-	  {
-	    err = calc_eclosure_iter (&eclosure_elem, dfa, edest, false);
-	    if (BE (err != REG_NOERROR, 0))
-	      return err;
-	  }
-	else
-	  eclosure_elem = dfa->eclosures[edest];
-	/* Merge the epsilon closure of 'edest'.  */
-	err = re_node_set_merge (&eclosure, &eclosure_elem);
-	if (BE (err != REG_NOERROR, 0))
-	  return err;
-	/* If the epsilon closure of 'edest' is incomplete,
-	   the epsilon closure of this node is also incomplete.  */
-	if (dfa->eclosures[edest].nelem == 0)
-	  {
-	    incomplete = true;
-	    re_node_set_free (&eclosure_elem);
-	  }
-      }
-
-  /* An epsilon closure includes itself.  */
-  ok = re_node_set_insert (&eclosure, node);
-  if (BE (! ok, 0))
-    return REG_ESPACE;
-  if (incomplete && !root)
-    dfa->eclosures[node].nelem = 0;
-  else
-    dfa->eclosures[node] = eclosure;
-  *new_set = eclosure;
-  return REG_NOERROR;
-}
-
-/* Functions for token which are used in the parser.  */
-
-/* Fetch a token from INPUT.
-   We must not use this function inside bracket expressions.  */
-
-static void
-internal_function
-fetch_token (re_token_t *result, re_string_t *input, reg_syntax_t syntax)
-{
-  re_string_skip_bytes (input, peek_token (result, input, syntax));
-}
-
-/* Peek a token from INPUT, and return the length of the token.
-   We must not use this function inside bracket expressions.  */
-
-static int
-internal_function
-peek_token (re_token_t *token, re_string_t *input, reg_syntax_t syntax)
-{
-  unsigned char c;
-
-  if (re_string_eoi (input))
-    {
-      token->type = END_OF_RE;
-      return 0;
-    }
-
-  c = re_string_peek_byte (input, 0);
-  token->opr.c = c;
-
-  token->word_char = 0;
-#ifdef RE_ENABLE_I18N
-  token->mb_partial = 0;
-  if (input->mb_cur_max > 1 &&
-      !re_string_first_byte (input, re_string_cur_idx (input)))
-    {
-      token->type = CHARACTER;
-      token->mb_partial = 1;
-      return 1;
-    }
-#endif
-  if (c == '\\')
-    {
-      unsigned char c2;
-      if (re_string_cur_idx (input) + 1 >= re_string_length (input))
-	{
-	  token->type = BACK_SLASH;
-	  return 1;
-	}
-
-      c2 = re_string_peek_byte_case (input, 1);
-      token->opr.c = c2;
-      token->type = CHARACTER;
-#ifdef RE_ENABLE_I18N
-      if (input->mb_cur_max > 1)
-	{
-	  wint_t wc = re_string_wchar_at (input,
-					  re_string_cur_idx (input) + 1);
-	  token->word_char = IS_WIDE_WORD_CHAR (wc) != 0;
-	}
-      else
-#endif
-	token->word_char = IS_WORD_CHAR (c2) != 0;
-
-      switch (c2)
-	{
-	case '|':
-	  if (!(syntax & RE_LIMITED_OPS) && !(syntax & RE_NO_BK_VBAR))
-	    token->type = OP_ALT;
-	  break;
-	case '1': case '2': case '3': case '4': case '5':
-	case '6': case '7': case '8': case '9':
-	  if (!(syntax & RE_NO_BK_REFS))
-	    {
-	      token->type = OP_BACK_REF;
-	      token->opr.idx = c2 - '1';
-	    }
-	  break;
-	case '<':
-	  if (!(syntax & RE_NO_GNU_OPS))
-	    {
-	      token->type = ANCHOR;
-	      token->opr.ctx_type = WORD_FIRST;
-	    }
-	  break;
-	case '>':
-	  if (!(syntax & RE_NO_GNU_OPS))
-	    {
-	      token->type = ANCHOR;
-	      token->opr.ctx_type = WORD_LAST;
-	    }
-	  break;
-	case 'b':
-	  if (!(syntax & RE_NO_GNU_OPS))
-	    {
-	      token->type = ANCHOR;
-	      token->opr.ctx_type = WORD_DELIM;
-	    }
-	  break;
-	case 'B':
-	  if (!(syntax & RE_NO_GNU_OPS))
-	    {
-	      token->type = ANCHOR;
-	      token->opr.ctx_type = NOT_WORD_DELIM;
-	    }
-	  break;
-	case 'w':
-	  if (!(syntax & RE_NO_GNU_OPS))
-	    token->type = OP_WORD;
-	  break;
-	case 'W':
-	  if (!(syntax & RE_NO_GNU_OPS))
-	    token->type = OP_NOTWORD;
-	  break;
-	case 's':
-	  if (!(syntax & RE_NO_GNU_OPS))
-	    token->type = OP_SPACE;
-	  break;
-	case 'S':
-	  if (!(syntax & RE_NO_GNU_OPS))
-	    token->type = OP_NOTSPACE;
-	  break;
-	case '`':
-	  if (!(syntax & RE_NO_GNU_OPS))
-	    {
-	      token->type = ANCHOR;
-	      token->opr.ctx_type = BUF_FIRST;
-	    }
-	  break;
-	case '\'':
-	  if (!(syntax & RE_NO_GNU_OPS))
-	    {
-	      token->type = ANCHOR;
-	      token->opr.ctx_type = BUF_LAST;
-	    }
-	  break;
-	case '(':
-	  if (!(syntax & RE_NO_BK_PARENS))
-	    token->type = OP_OPEN_SUBEXP;
-	  break;
-	case ')':
-	  if (!(syntax & RE_NO_BK_PARENS))
-	    token->type = OP_CLOSE_SUBEXP;
-	  break;
-	case '+':
-	  if (!(syntax & RE_LIMITED_OPS) && (syntax & RE_BK_PLUS_QM))
-	    token->type = OP_DUP_PLUS;
-	  break;
-	case '?':
-	  if (!(syntax & RE_LIMITED_OPS) && (syntax & RE_BK_PLUS_QM))
-	    token->type = OP_DUP_QUESTION;
-	  break;
-	case '{':
-	  if ((syntax & RE_INTERVALS) && (!(syntax & RE_NO_BK_BRACES)))
-	    token->type = OP_OPEN_DUP_NUM;
-	  break;
-	case '}':
-	  if ((syntax & RE_INTERVALS) && (!(syntax & RE_NO_BK_BRACES)))
-	    token->type = OP_CLOSE_DUP_NUM;
-	  break;
-	default:
-	  break;
-	}
-      return 2;
-    }
-
-  token->type = CHARACTER;
-#ifdef RE_ENABLE_I18N
-  if (input->mb_cur_max > 1)
-    {
-      wint_t wc = re_string_wchar_at (input, re_string_cur_idx (input));
-      token->word_char = IS_WIDE_WORD_CHAR (wc) != 0;
-    }
-  else
-#endif
-    token->word_char = IS_WORD_CHAR (token->opr.c);
-
-  switch (c)
-    {
-    case '\n':
-      if (syntax & RE_NEWLINE_ALT)
-	token->type = OP_ALT;
-      break;
-    case '|':
-      if (!(syntax & RE_LIMITED_OPS) && (syntax & RE_NO_BK_VBAR))
-	token->type = OP_ALT;
-      break;
-    case '*':
-      token->type = OP_DUP_ASTERISK;
-      break;
-    case '+':
-      if (!(syntax & RE_LIMITED_OPS) && !(syntax & RE_BK_PLUS_QM))
-	token->type = OP_DUP_PLUS;
-      break;
-    case '?':
-      if (!(syntax & RE_LIMITED_OPS) && !(syntax & RE_BK_PLUS_QM))
-	token->type = OP_DUP_QUESTION;
-      break;
-    case '{':
-      if ((syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
-	token->type = OP_OPEN_DUP_NUM;
-      break;
-    case '}':
-      if ((syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
-	token->type = OP_CLOSE_DUP_NUM;
-      break;
-    case '(':
-      if (syntax & RE_NO_BK_PARENS)
-	token->type = OP_OPEN_SUBEXP;
-      break;
-    case ')':
-      if (syntax & RE_NO_BK_PARENS)
-	token->type = OP_CLOSE_SUBEXP;
-      break;
-    case '[':
-      token->type = OP_OPEN_BRACKET;
-      break;
-    case '.':
-      token->type = OP_PERIOD;
-      break;
-    case '^':
-      if (!(syntax & (RE_CONTEXT_INDEP_ANCHORS | RE_CARET_ANCHORS_HERE)) &&
-	  re_string_cur_idx (input) != 0)
-	{
-	  char prev = re_string_peek_byte (input, -1);
-	  if (!(syntax & RE_NEWLINE_ALT) || prev != '\n')
-	    break;
-	}
-      token->type = ANCHOR;
-      token->opr.ctx_type = LINE_FIRST;
-      break;
-    case '$':
-      if (!(syntax & RE_CONTEXT_INDEP_ANCHORS) &&
-	  re_string_cur_idx (input) + 1 != re_string_length (input))
-	{
-	  re_token_t next;
-	  re_string_skip_bytes (input, 1);
-	  peek_token (&next, input, syntax);
-	  re_string_skip_bytes (input, -1);
-	  if (next.type != OP_ALT && next.type != OP_CLOSE_SUBEXP)
-	    break;
-	}
-      token->type = ANCHOR;
-      token->opr.ctx_type = LINE_LAST;
-      break;
-    default:
-      break;
-    }
-  return 1;
-}
-
-/* Peek a token from INPUT, and return the length of the token.
-   We must not use this function out of bracket expressions.  */
-
-static int
-internal_function
-peek_token_bracket (re_token_t *token, re_string_t *input, reg_syntax_t syntax)
-{
-  unsigned char c;
-  if (re_string_eoi (input))
-    {
-      token->type = END_OF_RE;
-      return 0;
-    }
-  c = re_string_peek_byte (input, 0);
-  token->opr.c = c;
-
-#ifdef RE_ENABLE_I18N
-  if (input->mb_cur_max > 1 &&
-      !re_string_first_byte (input, re_string_cur_idx (input)))
-    {
-      token->type = CHARACTER;
-      return 1;
-    }
-#endif /* RE_ENABLE_I18N */
-
-  if (c == '\\' && (syntax & RE_BACKSLASH_ESCAPE_IN_LISTS)
-      && re_string_cur_idx (input) + 1 < re_string_length (input))
-    {
-      /* In this case, '\' escape a character.  */
-      unsigned char c2;
-      re_string_skip_bytes (input, 1);
-      c2 = re_string_peek_byte (input, 0);
-      token->opr.c = c2;
-      token->type = CHARACTER;
-      return 1;
-    }
-  if (c == '[') /* '[' is a special char in a bracket exps.  */
-    {
-      unsigned char c2;
-      int token_len;
-      if (re_string_cur_idx (input) + 1 < re_string_length (input))
-	c2 = re_string_peek_byte (input, 1);
-      else
-	c2 = 0;
-      token->opr.c = c2;
-      token_len = 2;
-      switch (c2)
-	{
-	case '.':
-	  token->type = OP_OPEN_COLL_ELEM;
-	  break;
-	case '=':
-	  token->type = OP_OPEN_EQUIV_CLASS;
-	  break;
-	case ':':
-	  if (syntax & RE_CHAR_CLASSES)
-	    {
-	      token->type = OP_OPEN_CHAR_CLASS;
-	      break;
-	    }
-	  /* else fall through.  */
-	default:
-	  token->type = CHARACTER;
-	  token->opr.c = c;
-	  token_len = 1;
-	  break;
-	}
-      return token_len;
-    }
-  switch (c)
-    {
-    case '-':
-      token->type = OP_CHARSET_RANGE;
-      break;
-    case ']':
-      token->type = OP_CLOSE_BRACKET;
-      break;
-    case '^':
-      token->type = OP_NON_MATCH_LIST;
-      break;
-    default:
-      token->type = CHARACTER;
-    }
-  return 1;
-}
-
-/* Functions for parser.  */
-
-/* Entry point of the parser.
-   Parse the regular expression REGEXP and return the structure tree.
-   If an error occurs, ERR is set by error code, and return NULL.
-   This function build the following tree, from regular expression <reg_exp>:
-	   CAT
-	   / \
-	  /   \
-   <reg_exp>  EOR
-
-   CAT means concatenation.
-   EOR means end of regular expression.  */
-
-static bin_tree_t *
-parse (re_string_t *regexp, regex_t *preg, reg_syntax_t syntax,
-       reg_errcode_t *err)
-{
-  re_dfa_t *dfa = preg->buffer;
-  bin_tree_t *tree, *eor, *root;
-  re_token_t current_token;
-  dfa->syntax = syntax;
-  fetch_token (&current_token, regexp, syntax | RE_CARET_ANCHORS_HERE);
-  tree = parse_reg_exp (regexp, preg, &current_token, syntax, 0, err);
-  if (BE (*err != REG_NOERROR && tree == NULL, 0))
-    return NULL;
-  eor = create_tree (dfa, NULL, NULL, END_OF_RE);
-  if (tree != NULL)
-    root = create_tree (dfa, tree, eor, CONCAT);
-  else
-    root = eor;
-  if (BE (eor == NULL || root == NULL, 0))
-    {
-      *err = REG_ESPACE;
-      return NULL;
-    }
-  return root;
-}
-
-/* This function build the following tree, from regular expression
-   <branch1>|<branch2>:
-	   ALT
-	   / \
-	  /   \
-   <branch1> <branch2>
-
-   ALT means alternative, which represents the operator '|'.  */
-
-static bin_tree_t *
-parse_reg_exp (re_string_t *regexp, regex_t *preg, re_token_t *token,
-	       reg_syntax_t syntax, Idx nest, reg_errcode_t *err)
-{
-  re_dfa_t *dfa = preg->buffer;
-  bin_tree_t *tree, *branch = NULL;
-  tree = parse_branch (regexp, preg, token, syntax, nest, err);
-  if (BE (*err != REG_NOERROR && tree == NULL, 0))
-    return NULL;
-
-  while (token->type == OP_ALT)
-    {
-      fetch_token (token, regexp, syntax | RE_CARET_ANCHORS_HERE);
-      if (token->type != OP_ALT && token->type != END_OF_RE
-	  && (nest == 0 || token->type != OP_CLOSE_SUBEXP))
-	{
-	  branch = parse_branch (regexp, preg, token, syntax, nest, err);
-	  if (BE (*err != REG_NOERROR && branch == NULL, 0))
-	    return NULL;
-	}
-      else
-	branch = NULL;
-      tree = create_tree (dfa, tree, branch, OP_ALT);
-      if (BE (tree == NULL, 0))
-	{
-	  *err = REG_ESPACE;
-	  return NULL;
-	}
-    }
-  return tree;
-}
-
-/* This function build the following tree, from regular expression
-   <exp1><exp2>:
-	CAT
-	/ \
-       /   \
-   <exp1> <exp2>
-
-   CAT means concatenation.  */
-
-static bin_tree_t *
-parse_branch (re_string_t *regexp, regex_t *preg, re_token_t *token,
-	      reg_syntax_t syntax, Idx nest, reg_errcode_t *err)
-{
-  bin_tree_t *tree, *expr;
-  re_dfa_t *dfa = preg->buffer;
-  tree = parse_expression (regexp, preg, token, syntax, nest, err);
-  if (BE (*err != REG_NOERROR && tree == NULL, 0))
-    return NULL;
-
-  while (token->type != OP_ALT && token->type != END_OF_RE
-	 && (nest == 0 || token->type != OP_CLOSE_SUBEXP))
-    {
-      expr = parse_expression (regexp, preg, token, syntax, nest, err);
-      if (BE (*err != REG_NOERROR && expr == NULL, 0))
-	{
-	  if (tree != NULL)
-	    postorder (tree, free_tree, NULL);
-	  return NULL;
-	}
-      if (tree != NULL && expr != NULL)
-	{
-	  bin_tree_t *newtree = create_tree (dfa, tree, expr, CONCAT);
-	  if (newtree == NULL)
-	    {
-	      postorder (expr, free_tree, NULL);
-	      postorder (tree, free_tree, NULL);
-	      *err = REG_ESPACE;
-	      return NULL;
-	    }
-	  tree = newtree;
-	}
-      else if (tree == NULL)
-	tree = expr;
-      /* Otherwise expr == NULL, we don't need to create new tree.  */
-    }
-  return tree;
-}
-
-/* This function build the following tree, from regular expression a*:
-	 *
-	 |
-	 a
-*/
-
-static bin_tree_t *
-parse_expression (re_string_t *regexp, regex_t *preg, re_token_t *token,
-		  reg_syntax_t syntax, Idx nest, reg_errcode_t *err)
-{
-  re_dfa_t *dfa = preg->buffer;
-  bin_tree_t *tree;
-  switch (token->type)
-    {
-    case CHARACTER:
-      tree = create_token_tree (dfa, NULL, NULL, token);
-      if (BE (tree == NULL, 0))
-	{
-	  *err = REG_ESPACE;
-	  return NULL;
-	}
-#ifdef RE_ENABLE_I18N
-      if (dfa->mb_cur_max > 1)
-	{
-	  while (!re_string_eoi (regexp)
-		 && !re_string_first_byte (regexp, re_string_cur_idx (regexp)))
-	    {
-	      bin_tree_t *mbc_remain;
-	      fetch_token (token, regexp, syntax);
-	      mbc_remain = create_token_tree (dfa, NULL, NULL, token);
-	      tree = create_tree (dfa, tree, mbc_remain, CONCAT);
-	      if (BE (mbc_remain == NULL || tree == NULL, 0))
-		{
-		  *err = REG_ESPACE;
-		  return NULL;
-		}
-	    }
-	}
-#endif
-      break;
-    case OP_OPEN_SUBEXP:
-      tree = parse_sub_exp (regexp, preg, token, syntax, nest + 1, err);
-      if (BE (*err != REG_NOERROR && tree == NULL, 0))
-	return NULL;
-      break;
-    case OP_OPEN_BRACKET:
-      tree = parse_bracket_exp (regexp, dfa, token, syntax, err);
-      if (BE (*err != REG_NOERROR && tree == NULL, 0))
-	return NULL;
-      break;
-    case OP_BACK_REF:
-      if (!BE (dfa->completed_bkref_map & (1 << token->opr.idx), 1))
-	{
-	  *err = REG_ESUBREG;
-	  return NULL;
-	}
-      dfa->used_bkref_map |= 1 << token->opr.idx;
-      tree = create_token_tree (dfa, NULL, NULL, token);
-      if (BE (tree == NULL, 0))
-	{
-	  *err = REG_ESPACE;
-	  return NULL;
-	}
-      ++dfa->nbackref;
-      dfa->has_mb_node = 1;
-      break;
-    case OP_OPEN_DUP_NUM:
-      if (syntax & RE_CONTEXT_INVALID_DUP)
-	{
-	  *err = REG_BADRPT;
-	  return NULL;
-	}
-      /* FALLTHROUGH */
-    case OP_DUP_ASTERISK:
-    case OP_DUP_PLUS:
-    case OP_DUP_QUESTION:
-      if (syntax & RE_CONTEXT_INVALID_OPS)
-	{
-	  *err = REG_BADRPT;
-	  return NULL;
-	}
-      else if (syntax & RE_CONTEXT_INDEP_OPS)
-	{
-	  fetch_token (token, regexp, syntax);
-	  return parse_expression (regexp, preg, token, syntax, nest, err);
-	}
-      /* else fall through  */
-    case OP_CLOSE_SUBEXP:
-      if ((token->type == OP_CLOSE_SUBEXP) &&
-	  !(syntax & RE_UNMATCHED_RIGHT_PAREN_ORD))
-	{
-	  *err = REG_ERPAREN;
-	  return NULL;
-	}
-      /* else fall through  */
-    case OP_CLOSE_DUP_NUM:
-      /* We treat it as a normal character.  */
-
-      /* Then we can these characters as normal characters.  */
-      token->type = CHARACTER;
-      /* mb_partial and word_char bits should be initialized already
-	 by peek_token.  */
-      tree = create_token_tree (dfa, NULL, NULL, token);
-      if (BE (tree == NULL, 0))
-	{
-	  *err = REG_ESPACE;
-	  return NULL;
-	}
-      break;
-    case ANCHOR:
-      if ((token->opr.ctx_type
-	   & (WORD_DELIM | NOT_WORD_DELIM | WORD_FIRST | WORD_LAST))
-	  && dfa->word_ops_used == 0)
-	init_word_char (dfa);
-      if (token->opr.ctx_type == WORD_DELIM
-	  || token->opr.ctx_type == NOT_WORD_DELIM)
-	{
-	  bin_tree_t *tree_first, *tree_last;
-	  if (token->opr.ctx_type == WORD_DELIM)
-	    {
-	      token->opr.ctx_type = WORD_FIRST;
-	      tree_first = create_token_tree (dfa, NULL, NULL, token);
-	      token->opr.ctx_type = WORD_LAST;
-	    }
-	  else
-	    {
-	      token->opr.ctx_type = INSIDE_WORD;
-	      tree_first = create_token_tree (dfa, NULL, NULL, token);
-	      token->opr.ctx_type = INSIDE_NOTWORD;
-	    }
-	  tree_last = create_token_tree (dfa, NULL, NULL, token);
-	  tree = create_tree (dfa, tree_first, tree_last, OP_ALT);
-	  if (BE (tree_first == NULL || tree_last == NULL || tree == NULL, 0))
-	    {
-	      *err = REG_ESPACE;
-	      return NULL;
-	    }
-	}
-      else
-	{
-	  tree = create_token_tree (dfa, NULL, NULL, token);
-	  if (BE (tree == NULL, 0))
-	    {
-	      *err = REG_ESPACE;
-	      return NULL;
-	    }
-	}
-      /* We must return here, since ANCHORs can't be followed
-	 by repetition operators.
-	 eg. RE"^*" is invalid or "<ANCHOR(^)><CHAR(*)>",
-	     it must not be "<ANCHOR(^)><REPEAT(*)>".  */
-      fetch_token (token, regexp, syntax);
-      return tree;
-    case OP_PERIOD:
-      tree = create_token_tree (dfa, NULL, NULL, token);
-      if (BE (tree == NULL, 0))
-	{
-	  *err = REG_ESPACE;
-	  return NULL;
-	}
-      if (dfa->mb_cur_max > 1)
-	dfa->has_mb_node = 1;
-      break;
-    case OP_WORD:
-    case OP_NOTWORD:
-      tree = build_charclass_op (dfa, regexp->trans,
-				 "alnum",
-				 "_",
-				 token->type == OP_NOTWORD, err);
-      if (BE (*err != REG_NOERROR && tree == NULL, 0))
-	return NULL;
-      break;
-    case OP_SPACE:
-    case OP_NOTSPACE:
-      tree = build_charclass_op (dfa, regexp->trans,
-				 "space",
-				 "",
-				 token->type == OP_NOTSPACE, err);
-      if (BE (*err != REG_NOERROR && tree == NULL, 0))
-	return NULL;
-      break;
-    case OP_ALT:
-    case END_OF_RE:
-      return NULL;
-    case BACK_SLASH:
-      *err = REG_EESCAPE;
-      return NULL;
-    default:
-      /* Must not happen?  */
-#ifdef DEBUG
-      assert (0);
-#endif
-      return NULL;
-    }
-  fetch_token (token, regexp, syntax);
-
-  while (token->type == OP_DUP_ASTERISK || token->type == OP_DUP_PLUS
-	 || token->type == OP_DUP_QUESTION || token->type == OP_OPEN_DUP_NUM)
-    {
-      tree = parse_dup_op (tree, regexp, dfa, token, syntax, err);
-      if (BE (*err != REG_NOERROR && tree == NULL, 0))
-	return NULL;
-      /* In BRE consecutive duplications are not allowed.  */
-      if ((syntax & RE_CONTEXT_INVALID_DUP)
-	  && (token->type == OP_DUP_ASTERISK
-	      || token->type == OP_OPEN_DUP_NUM))
-	{
-	  *err = REG_BADRPT;
-	  return NULL;
-	}
-    }
-
-  return tree;
-}
-
-/* This function build the following tree, from regular expression
-   (<reg_exp>):
-	 SUBEXP
-	    |
-	<reg_exp>
-*/
-
-static bin_tree_t *
-parse_sub_exp (re_string_t *regexp, regex_t *preg, re_token_t *token,
-	       reg_syntax_t syntax, Idx nest, reg_errcode_t *err)
-{
-  re_dfa_t *dfa = preg->buffer;
-  bin_tree_t *tree;
-  size_t cur_nsub;
-  cur_nsub = preg->re_nsub++;
-
-  fetch_token (token, regexp, syntax | RE_CARET_ANCHORS_HERE);
-
-  /* The subexpression may be a null string.  */
-  if (token->type == OP_CLOSE_SUBEXP)
-    tree = NULL;
-  else
-    {
-      tree = parse_reg_exp (regexp, preg, token, syntax, nest, err);
-      if (BE (*err == REG_NOERROR && token->type != OP_CLOSE_SUBEXP, 0))
-	{
-	  if (tree != NULL)
-	    postorder (tree, free_tree, NULL);
-	  *err = REG_EPAREN;
-	}
-      if (BE (*err != REG_NOERROR, 0))
-	return NULL;
-    }
-
-  if (cur_nsub <= '9' - '1')
-    dfa->completed_bkref_map |= 1 << cur_nsub;
-
-  tree = create_tree (dfa, tree, NULL, SUBEXP);
-  if (BE (tree == NULL, 0))
-    {
-      *err = REG_ESPACE;
-      return NULL;
-    }
-  tree->token.opr.idx = cur_nsub;
-  return tree;
-}
-
-/* This function parse repetition operators like "*", "+", "{1,3}" etc.  */
-
-static bin_tree_t *
-parse_dup_op (bin_tree_t *elem, re_string_t *regexp, re_dfa_t *dfa,
-	      re_token_t *token, reg_syntax_t syntax, reg_errcode_t *err)
-{
-  bin_tree_t *tree = NULL, *old_tree = NULL;
-  Idx i, start, end, start_idx = re_string_cur_idx (regexp);
-  re_token_t start_token = *token;
-
-  if (token->type == OP_OPEN_DUP_NUM)
-    {
-      end = 0;
-      start = fetch_number (regexp, token, syntax);
-      if (start == REG_MISSING)
-	{
-	  if (token->type == CHARACTER && token->opr.c == ',')
-	    start = 0; /* We treat "{,m}" as "{0,m}".  */
-	  else
-	    {
-	      *err = REG_BADBR; /* <re>{} is invalid.  */
-	      return NULL;
-	    }
-	}
-      if (BE (start != REG_ERROR, 1))
-	{
-	  /* We treat "{n}" as "{n,n}".  */
-	  end = ((token->type == OP_CLOSE_DUP_NUM) ? start
-		 : ((token->type == CHARACTER && token->opr.c == ',')
-		    ? fetch_number (regexp, token, syntax) : REG_ERROR));
-	}
-      if (BE (start == REG_ERROR || end == REG_ERROR, 0))
-	{
-	  /* Invalid sequence.  */
-	  if (BE (!(syntax & RE_INVALID_INTERVAL_ORD), 0))
-	    {
-	      if (token->type == END_OF_RE)
-		*err = REG_EBRACE;
-	      else
-		*err = REG_BADBR;
-
-	      return NULL;
-	    }
-
-	  /* If the syntax bit is set, rollback.  */
-	  re_string_set_index (regexp, start_idx);
-	  *token = start_token;
-	  token->type = CHARACTER;
-	  /* mb_partial and word_char bits should be already initialized by
-	     peek_token.  */
-	  return elem;
-	}
-
-      if (BE ((end != REG_MISSING && start > end)
-	      || token->type != OP_CLOSE_DUP_NUM, 0))
-	{
-	  /* First number greater than second.  */
-	  *err = REG_BADBR;
-	  return NULL;
-	}
-
-      if (BE (RE_DUP_MAX < (end == REG_MISSING ? start : end), 0))
-	{
-	  *err = REG_ESIZE;
-	  return NULL;
-	}
-    }
-  else
-    {
-      start = (token->type == OP_DUP_PLUS) ? 1 : 0;
-      end = (token->type == OP_DUP_QUESTION) ? 1 : REG_MISSING;
-    }
-
-  fetch_token (token, regexp, syntax);
-
-  if (BE (elem == NULL, 0))
-    return NULL;
-  if (BE (start == 0 && end == 0, 0))
-    {
-      postorder (elem, free_tree, NULL);
-      return NULL;
-    }
-
-  /* Extract "<re>{n,m}" to "<re><re>...<re><re>{0,<m-n>}".  */
-  if (BE (start > 0, 0))
-    {
-      tree = elem;
-      for (i = 2; i <= start; ++i)
-	{
-	  elem = duplicate_tree (elem, dfa);
-	  tree = create_tree (dfa, tree, elem, CONCAT);
-	  if (BE (elem == NULL || tree == NULL, 0))
-	    goto parse_dup_op_espace;
-	}
-
-      if (start == end)
-	return tree;
-
-      /* Duplicate ELEM before it is marked optional.  */
-      elem = duplicate_tree (elem, dfa);
-      old_tree = tree;
-    }
-  else
-    old_tree = NULL;
-
-  if (elem->token.type == SUBEXP)
-    {
-      uintptr_t subidx = elem->token.opr.idx;
-      postorder (elem, mark_opt_subexp, (void *) subidx);
-    }
-
-  tree = create_tree (dfa, elem, NULL,
-		      (end == REG_MISSING ? OP_DUP_ASTERISK : OP_ALT));
-  if (BE (tree == NULL, 0))
-    goto parse_dup_op_espace;
-
-/* From gnulib's "intprops.h":
-   True if the arithmetic type T is signed.  */
-#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
-
-  /* This loop is actually executed only when end != REG_MISSING,
-     to rewrite <re>{0,n} as (<re>(<re>...<re>?)?)?...  We have
-     already created the start+1-th copy.  */
-  if (TYPE_SIGNED (Idx) || end != REG_MISSING)
-    for (i = start + 2; i <= end; ++i)
-      {
-	elem = duplicate_tree (elem, dfa);
-	tree = create_tree (dfa, tree, elem, CONCAT);
-	if (BE (elem == NULL || tree == NULL, 0))
-	  goto parse_dup_op_espace;
-
-	tree = create_tree (dfa, tree, NULL, OP_ALT);
-	if (BE (tree == NULL, 0))
-	  goto parse_dup_op_espace;
-      }
-
-  if (old_tree)
-    tree = create_tree (dfa, old_tree, tree, CONCAT);
-
-  return tree;
-
- parse_dup_op_espace:
-  *err = REG_ESPACE;
-  return NULL;
-}
-
-/* Size of the names for collating symbol/equivalence_class/character_class.
-   I'm not sure, but maybe enough.  */
-#define BRACKET_NAME_BUF_SIZE 32
-
-#ifndef _LIBC
-  /* Local function for parse_bracket_exp only used in case of NOT _LIBC.
-     Build the range expression which starts from START_ELEM, and ends
-     at END_ELEM.  The result are written to MBCSET and SBCSET.
-     RANGE_ALLOC is the allocated size of mbcset->range_starts, and
-     mbcset->range_ends, is a pointer argument since we may
-     update it.  */
-
-static reg_errcode_t
-internal_function
-# ifdef RE_ENABLE_I18N
-build_range_exp (const reg_syntax_t syntax,
-                 bitset_t sbcset,
-                 re_charset_t *mbcset,
-                 Idx *range_alloc,
-                 const bracket_elem_t *start_elem,
-                 const bracket_elem_t *end_elem)
-# else /* not RE_ENABLE_I18N */
-build_range_exp (const reg_syntax_t syntax,
-                 bitset_t sbcset,
-                 const bracket_elem_t *start_elem,
-                 const bracket_elem_t *end_elem)
-# endif /* not RE_ENABLE_I18N */
-{
-  unsigned int start_ch, end_ch;
-  /* Equivalence Classes and Character Classes can't be a range start/end.  */
-  if (BE (start_elem->type == EQUIV_CLASS || start_elem->type == CHAR_CLASS
-	  || end_elem->type == EQUIV_CLASS || end_elem->type == CHAR_CLASS,
-	  0))
-    return REG_ERANGE;
-
-  /* We can handle no multi character collating elements without libc
-     support.  */
-  if (BE ((start_elem->type == COLL_SYM
-	   && strlen ((char *) start_elem->opr.name) > 1)
-	  || (end_elem->type == COLL_SYM
-	      && strlen ((char *) end_elem->opr.name) > 1), 0))
-    return REG_ECOLLATE;
-
-# ifdef RE_ENABLE_I18N
-  {
-    wchar_t wc;
-    wint_t start_wc;
-    wint_t end_wc;
-
-    start_ch = ((start_elem->type == SB_CHAR) ? start_elem->opr.ch
-		: ((start_elem->type == COLL_SYM) ? start_elem->opr.name[0]
-		   : 0));
-    end_ch = ((end_elem->type == SB_CHAR) ? end_elem->opr.ch
-	      : ((end_elem->type == COLL_SYM) ? end_elem->opr.name[0]
-		 : 0));
-    start_wc = ((start_elem->type == SB_CHAR || start_elem->type == COLL_SYM)
-		? __btowc (start_ch) : start_elem->opr.wch);
-    end_wc = ((end_elem->type == SB_CHAR || end_elem->type == COLL_SYM)
-	      ? __btowc (end_ch) : end_elem->opr.wch);
-    if (start_wc == WEOF || end_wc == WEOF)
-      return REG_ECOLLATE;
-    else if (BE ((syntax & RE_NO_EMPTY_RANGES) && start_wc > end_wc, 0))
-      return REG_ERANGE;
-
-    /* Got valid collation sequence values, add them as a new entry.
-       However, for !_LIBC we have no collation elements: if the
-       character set is single byte, the single byte character set
-       that we build below suffices.  parse_bracket_exp passes
-       no MBCSET if dfa->mb_cur_max == 1.  */
-    if (mbcset)
-      {
-	/* Check the space of the arrays.  */
-	if (BE (*range_alloc == mbcset->nranges, 0))
-	  {
-	    /* There is not enough space, need realloc.  */
-	    wchar_t *new_array_start, *new_array_end;
-	    Idx new_nranges;
-
-	    /* +1 in case of mbcset->nranges is 0.  */
-	    new_nranges = 2 * mbcset->nranges + 1;
-	    /* Use realloc since mbcset->range_starts and mbcset->range_ends
-	       are NULL if *range_alloc == 0.  */
-	    new_array_start = re_realloc (mbcset->range_starts, wchar_t,
-					  new_nranges);
-	    new_array_end = re_realloc (mbcset->range_ends, wchar_t,
-					new_nranges);
-
-	    if (BE (new_array_start == NULL || new_array_end == NULL, 0))
-	      return REG_ESPACE;
-
-	    mbcset->range_starts = new_array_start;
-	    mbcset->range_ends = new_array_end;
-	    *range_alloc = new_nranges;
-	  }
-
-	mbcset->range_starts[mbcset->nranges] = start_wc;
-	mbcset->range_ends[mbcset->nranges++] = end_wc;
-      }
-
-    /* Build the table for single byte characters.  */
-    for (wc = 0; wc < SBC_MAX; ++wc)
-      {
-	if (start_wc <= wc && wc <= end_wc)
-	  bitset_set (sbcset, wc);
-      }
-  }
-# else /* not RE_ENABLE_I18N */
-  {
-    unsigned int ch;
-    start_ch = ((start_elem->type == SB_CHAR ) ? start_elem->opr.ch
-		: ((start_elem->type == COLL_SYM) ? start_elem->opr.name[0]
-		   : 0));
-    end_ch = ((end_elem->type == SB_CHAR ) ? end_elem->opr.ch
-	      : ((end_elem->type == COLL_SYM) ? end_elem->opr.name[0]
-		 : 0));
-    if (start_ch > end_ch)
-      return REG_ERANGE;
-    /* Build the table for single byte characters.  */
-    for (ch = 0; ch < SBC_MAX; ++ch)
-      if (start_ch <= ch  && ch <= end_ch)
-	bitset_set (sbcset, ch);
-  }
-# endif /* not RE_ENABLE_I18N */
-  return REG_NOERROR;
-}
-#endif /* not _LIBC */
-
-#ifndef _LIBC
-/* Helper function for parse_bracket_exp only used in case of NOT _LIBC..
-   Build the collating element which is represented by NAME.
-   The result are written to MBCSET and SBCSET.
-   COLL_SYM_ALLOC is the allocated size of mbcset->coll_sym, is a
-   pointer argument since we may update it.  */
-
-static reg_errcode_t
-internal_function
-# ifdef RE_ENABLE_I18N
-build_collating_symbol (bitset_t sbcset, re_charset_t *mbcset,
-			Idx *coll_sym_alloc, const unsigned char *name)
-# else /* not RE_ENABLE_I18N */
-build_collating_symbol (bitset_t sbcset, const unsigned char *name)
-# endif /* not RE_ENABLE_I18N */
-{
-  size_t name_len = strlen ((const char *) name);
-  if (BE (name_len != 1, 0))
-    return REG_ECOLLATE;
-  else
-    {
-      bitset_set (sbcset, name[0]);
-      return REG_NOERROR;
-    }
-}
-#endif /* not _LIBC */
-
-/* This function parse bracket expression like "[abc]", "[a-c]",
-   "[[.a-a.]]" etc.  */
-
-static bin_tree_t *
-parse_bracket_exp (re_string_t *regexp, re_dfa_t *dfa, re_token_t *token,
-		   reg_syntax_t syntax, reg_errcode_t *err)
-{
-#ifdef _LIBC
-  const unsigned char *collseqmb;
-  const char *collseqwc;
-  uint32_t nrules;
-  int32_t table_size;
-  const int32_t *symb_table;
-  const unsigned char *extra;
-
-  /* Local function for parse_bracket_exp used in _LIBC environment.
-     Seek the collating symbol entry corresponding to NAME.
-     Return the index of the symbol in the SYMB_TABLE,
-     or -1 if not found.  */
-
-  auto inline int32_t
-  __attribute__ ((always_inline))
-  seek_collating_symbol_entry (const unsigned char *name, size_t name_len)
-    {
-      int32_t elem;
-
-      for (elem = 0; elem < table_size; elem++)
-	if (symb_table[2 * elem] != 0)
-	  {
-	    int32_t idx = symb_table[2 * elem + 1];
-	    /* Skip the name of collating element name.  */
-	    idx += 1 + extra[idx];
-	    if (/* Compare the length of the name.  */
-		name_len == extra[idx]
-		/* Compare the name.  */
-		&& memcmp (name, &extra[idx + 1], name_len) == 0)
-	      /* Yep, this is the entry.  */
-	      return elem;
-	  }
-      return -1;
-    }
-
-  /* Local function for parse_bracket_exp used in _LIBC environment.
-     Look up the collation sequence value of BR_ELEM.
-     Return the value if succeeded, UINT_MAX otherwise.  */
-
-  auto inline unsigned int
-  __attribute__ ((always_inline))
-  lookup_collation_sequence_value (bracket_elem_t *br_elem)
-    {
-      if (br_elem->type == SB_CHAR)
-	{
-	  /*
-	  if (MB_CUR_MAX == 1)
-	  */
-	  if (nrules == 0)
-	    return collseqmb[br_elem->opr.ch];
-	  else
-	    {
-	      wint_t wc = __btowc (br_elem->opr.ch);
-	      return __collseq_table_lookup (collseqwc, wc);
-	    }
-	}
-      else if (br_elem->type == MB_CHAR)
-	{
-	  if (nrules != 0)
-	    return __collseq_table_lookup (collseqwc, br_elem->opr.wch);
-	}
-      else if (br_elem->type == COLL_SYM)
-	{
-	  size_t sym_name_len = strlen ((char *) br_elem->opr.name);
-	  if (nrules != 0)
-	    {
-	      int32_t elem, idx;
-	      elem = seek_collating_symbol_entry (br_elem->opr.name,
-						  sym_name_len);
-	      if (elem != -1)
-		{
-		  /* We found the entry.  */
-		  idx = symb_table[2 * elem + 1];
-		  /* Skip the name of collating element name.  */
-		  idx += 1 + extra[idx];
-		  /* Skip the byte sequence of the collating element.  */
-		  idx += 1 + extra[idx];
-		  /* Adjust for the alignment.  */
-		  idx = (idx + 3) & ~3;
-		  /* Skip the multibyte collation sequence value.  */
-		  idx += sizeof (unsigned int);
-		  /* Skip the wide char sequence of the collating element.  */
-		  idx += sizeof (unsigned int) *
-		    (1 + *(unsigned int *) (extra + idx));
-		  /* Return the collation sequence value.  */
-		  return *(unsigned int *) (extra + idx);
-		}
-	      else if (sym_name_len == 1)
-		{
-		  /* No valid character.  Match it as a single byte
-		     character.  */
-		  return collseqmb[br_elem->opr.name[0]];
-		}
-	    }
-	  else if (sym_name_len == 1)
-	    return collseqmb[br_elem->opr.name[0]];
-	}
-      return UINT_MAX;
-    }
-
-  /* Local function for parse_bracket_exp used in _LIBC environment.
-     Build the range expression which starts from START_ELEM, and ends
-     at END_ELEM.  The result are written to MBCSET and SBCSET.
-     RANGE_ALLOC is the allocated size of mbcset->range_starts, and
-     mbcset->range_ends, is a pointer argument since we may
-     update it.  */
-
-  auto inline reg_errcode_t
-  __attribute__ ((always_inline))
-  build_range_exp (bitset_t sbcset, re_charset_t *mbcset, int *range_alloc,
-		   bracket_elem_t *start_elem, bracket_elem_t *end_elem)
-    {
-      unsigned int ch;
-      uint32_t start_collseq;
-      uint32_t end_collseq;
-
-      /* Equivalence Classes and Character Classes can't be a range
-	 start/end.  */
-      if (BE (start_elem->type == EQUIV_CLASS || start_elem->type == CHAR_CLASS
-	      || end_elem->type == EQUIV_CLASS || end_elem->type == CHAR_CLASS,
-	      0))
-	return REG_ERANGE;
-
-      /* FIXME: Implement rational ranges here, too.  */
-      start_collseq = lookup_collation_sequence_value (start_elem);
-      end_collseq = lookup_collation_sequence_value (end_elem);
-      /* Check start/end collation sequence values.  */
-      if (BE (start_collseq == UINT_MAX || end_collseq == UINT_MAX, 0))
-	return REG_ECOLLATE;
-      if (BE ((syntax & RE_NO_EMPTY_RANGES) && start_collseq > end_collseq, 0))
-	return REG_ERANGE;
-
-      /* Got valid collation sequence values, add them as a new entry.
-	 However, if we have no collation elements, and the character set
-	 is single byte, the single byte character set that we
-	 build below suffices. */
-      if (nrules > 0 || dfa->mb_cur_max > 1)
-	{
-	  /* Check the space of the arrays.  */
-	  if (BE (*range_alloc == mbcset->nranges, 0))
-	    {
-	      /* There is not enough space, need realloc.  */
-	      uint32_t *new_array_start;
-	      uint32_t *new_array_end;
-	      Idx new_nranges;
-
-	      /* +1 in case of mbcset->nranges is 0.  */
-	      new_nranges = 2 * mbcset->nranges + 1;
-	      new_array_start = re_realloc (mbcset->range_starts, uint32_t,
-					    new_nranges);
-	      new_array_end = re_realloc (mbcset->range_ends, uint32_t,
-					  new_nranges);
-
-	      if (BE (new_array_start == NULL || new_array_end == NULL, 0))
-		return REG_ESPACE;
-
-	      mbcset->range_starts = new_array_start;
-	      mbcset->range_ends = new_array_end;
-	      *range_alloc = new_nranges;
-	    }
-
-	  mbcset->range_starts[mbcset->nranges] = start_collseq;
-	  mbcset->range_ends[mbcset->nranges++] = end_collseq;
-	}
-
-      /* Build the table for single byte characters.  */
-      for (ch = 0; ch < SBC_MAX; ch++)
-	{
-	  uint32_t ch_collseq;
-	  /*
-	  if (MB_CUR_MAX == 1)
-	  */
-	  if (nrules == 0)
-	    ch_collseq = collseqmb[ch];
-	  else
-	    ch_collseq = __collseq_table_lookup (collseqwc, __btowc (ch));
-	  if (start_collseq <= ch_collseq && ch_collseq <= end_collseq)
-	    bitset_set (sbcset, ch);
-	}
-      return REG_NOERROR;
-    }
-
-  /* Local function for parse_bracket_exp used in _LIBC environment.
-     Build the collating element which is represented by NAME.
-     The result are written to MBCSET and SBCSET.
-     COLL_SYM_ALLOC is the allocated size of mbcset->coll_sym, is a
-     pointer argument since we may update it.  */
-
-  auto inline reg_errcode_t
-  __attribute__ ((always_inline))
-  build_collating_symbol (bitset_t sbcset, re_charset_t *mbcset,
-			  Idx *coll_sym_alloc, const unsigned char *name)
-    {
-      int32_t elem, idx;
-      size_t name_len = strlen ((const char *) name);
-      if (nrules != 0)
-	{
-	  elem = seek_collating_symbol_entry (name, name_len);
-	  if (elem != -1)
-	    {
-	      /* We found the entry.  */
-	      idx = symb_table[2 * elem + 1];
-	      /* Skip the name of collating element name.  */
-	      idx += 1 + extra[idx];
-	    }
-	  else if (name_len == 1)
-	    {
-	      /* No valid character, treat it as a normal
-		 character.  */
-	      bitset_set (sbcset, name[0]);
-	      return REG_NOERROR;
-	    }
-	  else
-	    return REG_ECOLLATE;
-
-	  /* Got valid collation sequence, add it as a new entry.  */
-	  /* Check the space of the arrays.  */
-	  if (BE (*coll_sym_alloc == mbcset->ncoll_syms, 0))
-	    {
-	      /* Not enough, realloc it.  */
-	      /* +1 in case of mbcset->ncoll_syms is 0.  */
-	      Idx new_coll_sym_alloc = 2 * mbcset->ncoll_syms + 1;
-	      /* Use realloc since mbcset->coll_syms is NULL
-		 if *alloc == 0.  */
-	      int32_t *new_coll_syms = re_realloc (mbcset->coll_syms, int32_t,
-						   new_coll_sym_alloc);
-	      if (BE (new_coll_syms == NULL, 0))
-		return REG_ESPACE;
-	      mbcset->coll_syms = new_coll_syms;
-	      *coll_sym_alloc = new_coll_sym_alloc;
-	    }
-	  mbcset->coll_syms[mbcset->ncoll_syms++] = idx;
-	  return REG_NOERROR;
-	}
-      else
-	{
-	  if (BE (name_len != 1, 0))
-	    return REG_ECOLLATE;
-	  else
-	    {
-	      bitset_set (sbcset, name[0]);
-	      return REG_NOERROR;
-	    }
-	}
-    }
-#endif
-
-  re_token_t br_token;
-  re_bitset_ptr_t sbcset;
-#ifdef RE_ENABLE_I18N
-  re_charset_t *mbcset;
-  Idx coll_sym_alloc = 0, range_alloc = 0, mbchar_alloc = 0;
-  Idx equiv_class_alloc = 0, char_class_alloc = 0;
-#endif /* not RE_ENABLE_I18N */
-  bool non_match = false;
-  bin_tree_t *work_tree;
-  int token_len;
-  bool first_round = true;
-#ifdef _LIBC
-  collseqmb = (const unsigned char *)
-    _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQMB);
-  nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES);
-  if (nrules)
-    {
-      /*
-      if (MB_CUR_MAX > 1)
-      */
-      collseqwc = _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQWC);
-      table_size = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_SYMB_HASH_SIZEMB);
-      symb_table = (const int32_t *) _NL_CURRENT (LC_COLLATE,
-						  _NL_COLLATE_SYMB_TABLEMB);
-      extra = (const unsigned char *) _NL_CURRENT (LC_COLLATE,
-						   _NL_COLLATE_SYMB_EXTRAMB);
-    }
-#endif
-  sbcset = (re_bitset_ptr_t) calloc (sizeof (bitset_t), 1);
-#ifdef RE_ENABLE_I18N
-  mbcset = (re_charset_t *) calloc (sizeof (re_charset_t), 1);
-#endif /* RE_ENABLE_I18N */
-#ifdef RE_ENABLE_I18N
-  if (BE (sbcset == NULL || mbcset == NULL, 0))
-#else
-  if (BE (sbcset == NULL, 0))
-#endif /* RE_ENABLE_I18N */
-    {
-      re_free (sbcset);
-#ifdef RE_ENABLE_I18N
-      re_free (mbcset);
-#endif
-      *err = REG_ESPACE;
-      return NULL;
-    }
-
-  token_len = peek_token_bracket (token, regexp, syntax);
-  if (BE (token->type == END_OF_RE, 0))
-    {
-      *err = REG_BADPAT;
-      goto parse_bracket_exp_free_return;
-    }
-  if (token->type == OP_NON_MATCH_LIST)
-    {
-#ifdef RE_ENABLE_I18N
-      mbcset->non_match = 1;
-#endif /* not RE_ENABLE_I18N */
-      non_match = true;
-      if (syntax & RE_HAT_LISTS_NOT_NEWLINE)
-	bitset_set (sbcset, '\n');
-      re_string_skip_bytes (regexp, token_len); /* Skip a token.  */
-      token_len = peek_token_bracket (token, regexp, syntax);
-      if (BE (token->type == END_OF_RE, 0))
-	{
-	  *err = REG_BADPAT;
-	  goto parse_bracket_exp_free_return;
-	}
-    }
-
-  /* We treat the first ']' as a normal character.  */
-  if (token->type == OP_CLOSE_BRACKET)
-    token->type = CHARACTER;
-
-  while (1)
-    {
-      bracket_elem_t start_elem, end_elem;
-      unsigned char start_name_buf[BRACKET_NAME_BUF_SIZE];
-      unsigned char end_name_buf[BRACKET_NAME_BUF_SIZE];
-      reg_errcode_t ret;
-      int token_len2 = 0;
-      bool is_range_exp = false;
-      re_token_t token2;
-
-      start_elem.opr.name = start_name_buf;
-      ret = parse_bracket_element (&start_elem, regexp, token, token_len, dfa,
-				   syntax, first_round);
-      if (BE (ret != REG_NOERROR, 0))
-	{
-	  *err = ret;
-	  goto parse_bracket_exp_free_return;
-	}
-      first_round = false;
-
-      /* Get information about the next token.  We need it in any case.  */
-      token_len = peek_token_bracket (token, regexp, syntax);
-
-      /* Do not check for ranges if we know they are not allowed.  */
-      if (start_elem.type != CHAR_CLASS && start_elem.type != EQUIV_CLASS)
-	{
-	  if (BE (token->type == END_OF_RE, 0))
-	    {
-	      *err = REG_EBRACK;
-	      goto parse_bracket_exp_free_return;
-	    }
-	  if (token->type == OP_CHARSET_RANGE)
-	    {
-	      re_string_skip_bytes (regexp, token_len); /* Skip '-'.  */
-	      token_len2 = peek_token_bracket (&token2, regexp, syntax);
-	      if (BE (token2.type == END_OF_RE, 0))
-		{
-		  *err = REG_EBRACK;
-		  goto parse_bracket_exp_free_return;
-		}
-	      if (token2.type == OP_CLOSE_BRACKET)
-		{
-		  /* We treat the last '-' as a normal character.  */
-		  re_string_skip_bytes (regexp, -token_len);
-		  token->type = CHARACTER;
-		}
-	      else
-		is_range_exp = true;
-	    }
-	}
-
-      if (is_range_exp == true)
-	{
-	  end_elem.opr.name = end_name_buf;
-	  ret = parse_bracket_element (&end_elem, regexp, &token2, token_len2,
-				       dfa, syntax, true);
-	  if (BE (ret != REG_NOERROR, 0))
-	    {
-	      *err = ret;
-	      goto parse_bracket_exp_free_return;
-	    }
-
-	  token_len = peek_token_bracket (token, regexp, syntax);
-
-#ifdef _LIBC
-	  *err = build_range_exp (sbcset, mbcset, &range_alloc,
-				  &start_elem, &end_elem);
-#else
-# ifdef RE_ENABLE_I18N
-	  *err = build_range_exp (syntax, sbcset,
-				  dfa->mb_cur_max > 1 ? mbcset : NULL,
-				  &range_alloc, &start_elem, &end_elem);
-# else
-	  *err = build_range_exp (syntax, sbcset, &start_elem, &end_elem);
-# endif
-#endif /* RE_ENABLE_I18N */
-	  if (BE (*err != REG_NOERROR, 0))
-	    goto parse_bracket_exp_free_return;
-	}
-      else
-	{
-	  switch (start_elem.type)
-	    {
-	    case SB_CHAR:
-	      bitset_set (sbcset, start_elem.opr.ch);
-	      break;
-#ifdef RE_ENABLE_I18N
-	    case MB_CHAR:
-	      /* Check whether the array has enough space.  */
-	      if (BE (mbchar_alloc == mbcset->nmbchars, 0))
-		{
-		  wchar_t *new_mbchars;
-		  /* Not enough, realloc it.  */
-		  /* +1 in case of mbcset->nmbchars is 0.  */
-		  mbchar_alloc = 2 * mbcset->nmbchars + 1;
-		  /* Use realloc since array is NULL if *alloc == 0.  */
-		  new_mbchars = re_realloc (mbcset->mbchars, wchar_t,
-					    mbchar_alloc);
-		  if (BE (new_mbchars == NULL, 0))
-		    goto parse_bracket_exp_espace;
-		  mbcset->mbchars = new_mbchars;
-		}
-	      mbcset->mbchars[mbcset->nmbchars++] = start_elem.opr.wch;
-	      break;
-#endif /* RE_ENABLE_I18N */
-	    case EQUIV_CLASS:
-	      *err = build_equiv_class (sbcset,
-#ifdef RE_ENABLE_I18N
-					mbcset, &equiv_class_alloc,
-#endif /* RE_ENABLE_I18N */
-					start_elem.opr.name);
-	      if (BE (*err != REG_NOERROR, 0))
-		goto parse_bracket_exp_free_return;
-	      break;
-	    case COLL_SYM:
-	      *err = build_collating_symbol (sbcset,
-#ifdef RE_ENABLE_I18N
-					     mbcset, &coll_sym_alloc,
-#endif /* RE_ENABLE_I18N */
-					     start_elem.opr.name);
-	      if (BE (*err != REG_NOERROR, 0))
-		goto parse_bracket_exp_free_return;
-	      break;
-	    case CHAR_CLASS:
-	      *err = build_charclass (regexp->trans, sbcset,
-#ifdef RE_ENABLE_I18N
-				      mbcset, &char_class_alloc,
-#endif /* RE_ENABLE_I18N */
-				      (const char *) start_elem.opr.name,
-				      syntax);
-	      if (BE (*err != REG_NOERROR, 0))
-	       goto parse_bracket_exp_free_return;
-	      break;
-	    default:
-	      assert (0);
-	      break;
-	    }
-	}
-      if (BE (token->type == END_OF_RE, 0))
-	{
-	  *err = REG_EBRACK;
-	  goto parse_bracket_exp_free_return;
-	}
-      if (token->type == OP_CLOSE_BRACKET)
-	break;
-    }
-
-  re_string_skip_bytes (regexp, token_len); /* Skip a token.  */
-
-  /* If it is non-matching list.  */
-  if (non_match)
-    bitset_not (sbcset);
-
-#ifdef RE_ENABLE_I18N
-  /* Ensure only single byte characters are set.  */
-  if (dfa->mb_cur_max > 1)
-    bitset_mask (sbcset, dfa->sb_char);
-
-  if (mbcset->nmbchars || mbcset->ncoll_syms || mbcset->nequiv_classes
-      || mbcset->nranges || (dfa->mb_cur_max > 1 && (mbcset->nchar_classes
-						     || mbcset->non_match)))
-    {
-      bin_tree_t *mbc_tree;
-      int sbc_idx;
-      /* Build a tree for complex bracket.  */
-      dfa->has_mb_node = 1;
-      br_token.type = COMPLEX_BRACKET;
-      br_token.opr.mbcset = mbcset;
-      mbc_tree = create_token_tree (dfa, NULL, NULL, &br_token);
-      if (BE (mbc_tree == NULL, 0))
-	goto parse_bracket_exp_espace;
-      for (sbc_idx = 0; sbc_idx < BITSET_WORDS; ++sbc_idx)
-	if (sbcset[sbc_idx])
-	  break;
-      /* If there are no bits set in sbcset, there is no point
-	 of having both SIMPLE_BRACKET and COMPLEX_BRACKET.  */
-      if (sbc_idx < BITSET_WORDS)
-	{
-	  /* Build a tree for simple bracket.  */
-	  br_token.type = SIMPLE_BRACKET;
-	  br_token.opr.sbcset = sbcset;
-	  work_tree = create_token_tree (dfa, NULL, NULL, &br_token);
-	  if (BE (work_tree == NULL, 0))
-	    goto parse_bracket_exp_espace;
-
-	  /* Then join them by ALT node.  */
-	  work_tree = create_tree (dfa, work_tree, mbc_tree, OP_ALT);
-	  if (BE (work_tree == NULL, 0))
-	    goto parse_bracket_exp_espace;
-	}
-      else
-	{
-	  re_free (sbcset);
-	  work_tree = mbc_tree;
-	}
-    }
-  else
-#endif /* not RE_ENABLE_I18N */
-    {
-#ifdef RE_ENABLE_I18N
-      free_charset (mbcset);
-#endif
-      /* Build a tree for simple bracket.  */
-      br_token.type = SIMPLE_BRACKET;
-      br_token.opr.sbcset = sbcset;
-      work_tree = create_token_tree (dfa, NULL, NULL, &br_token);
-      if (BE (work_tree == NULL, 0))
-	goto parse_bracket_exp_espace;
-    }
-  return work_tree;
-
- parse_bracket_exp_espace:
-  *err = REG_ESPACE;
- parse_bracket_exp_free_return:
-  re_free (sbcset);
-#ifdef RE_ENABLE_I18N
-  free_charset (mbcset);
-#endif /* RE_ENABLE_I18N */
-  return NULL;
-}
-
-/* Parse an element in the bracket expression.  */
-
-static reg_errcode_t
-parse_bracket_element (bracket_elem_t *elem, re_string_t *regexp,
-		       re_token_t *token, int token_len, re_dfa_t *dfa,
-		       reg_syntax_t syntax, bool accept_hyphen)
-{
-#ifdef RE_ENABLE_I18N
-  int cur_char_size;
-  cur_char_size = re_string_char_size_at (regexp, re_string_cur_idx (regexp));
-  if (cur_char_size > 1)
-    {
-      elem->type = MB_CHAR;
-      elem->opr.wch = re_string_wchar_at (regexp, re_string_cur_idx (regexp));
-      re_string_skip_bytes (regexp, cur_char_size);
-      return REG_NOERROR;
-    }
-#endif /* RE_ENABLE_I18N */
-  re_string_skip_bytes (regexp, token_len); /* Skip a token.  */
-  if (token->type == OP_OPEN_COLL_ELEM || token->type == OP_OPEN_CHAR_CLASS
-      || token->type == OP_OPEN_EQUIV_CLASS)
-    return parse_bracket_symbol (elem, regexp, token);
-  if (BE (token->type == OP_CHARSET_RANGE, 0) && !accept_hyphen)
-    {
-      /* A '-' must only appear as anything but a range indicator before
-	 the closing bracket.  Everything else is an error.  */
-      re_token_t token2;
-      (void) peek_token_bracket (&token2, regexp, syntax);
-      if (token2.type != OP_CLOSE_BRACKET)
-	/* The actual error value is not standardized since this whole
-	   case is undefined.  But ERANGE makes good sense.  */
-	return REG_ERANGE;
-    }
-  elem->type = SB_CHAR;
-  elem->opr.ch = token->opr.c;
-  return REG_NOERROR;
-}
-
-/* Parse a bracket symbol in the bracket expression.  Bracket symbols are
-   such as [:<character_class>:], [.<collating_element>.], and
-   [=<equivalent_class>=].  */
-
-static reg_errcode_t
-parse_bracket_symbol (bracket_elem_t *elem, re_string_t *regexp,
-		      re_token_t *token)
-{
-  unsigned char ch, delim = token->opr.c;
-  int i = 0;
-  if (re_string_eoi(regexp))
-    return REG_EBRACK;
-  for (;; ++i)
-    {
-      if (i >= BRACKET_NAME_BUF_SIZE)
-	return REG_EBRACK;
-      if (token->type == OP_OPEN_CHAR_CLASS)
-	ch = re_string_fetch_byte_case (regexp);
-      else
-	ch = re_string_fetch_byte (regexp);
-      if (re_string_eoi(regexp))
-	return REG_EBRACK;
-      if (ch == delim && re_string_peek_byte (regexp, 0) == ']')
-	break;
-      elem->opr.name[i] = ch;
-    }
-  re_string_skip_bytes (regexp, 1);
-  elem->opr.name[i] = '\0';
-  switch (token->type)
-    {
-    case OP_OPEN_COLL_ELEM:
-      elem->type = COLL_SYM;
-      break;
-    case OP_OPEN_EQUIV_CLASS:
-      elem->type = EQUIV_CLASS;
-      break;
-    case OP_OPEN_CHAR_CLASS:
-      elem->type = CHAR_CLASS;
-      break;
-    default:
-      break;
-    }
-  return REG_NOERROR;
-}
-
-  /* Helper function for parse_bracket_exp.
-     Build the equivalence class which is represented by NAME.
-     The result are written to MBCSET and SBCSET.
-     EQUIV_CLASS_ALLOC is the allocated size of mbcset->equiv_classes,
-     is a pointer argument since we may update it.  */
-
-static reg_errcode_t
-#ifdef RE_ENABLE_I18N
-build_equiv_class (bitset_t sbcset, re_charset_t *mbcset,
-		   Idx *equiv_class_alloc, const unsigned char *name)
-#else /* not RE_ENABLE_I18N */
-build_equiv_class (bitset_t sbcset, const unsigned char *name)
-#endif /* not RE_ENABLE_I18N */
-{
-#ifdef _LIBC
-  uint32_t nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES);
-  if (nrules != 0)
-    {
-      const int32_t *table, *indirect;
-      const unsigned char *weights, *extra, *cp;
-      unsigned char char_buf[2];
-      int32_t idx1, idx2;
-      unsigned int ch;
-      size_t len;
-      /* This #include defines a local function!  */
-# include <locale/weight.h>
-      /* Calculate the index for equivalence class.  */
-      cp = name;
-      table = (const int32_t *) _NL_CURRENT (LC_COLLATE, _NL_COLLATE_TABLEMB);
-      weights = (const unsigned char *) _NL_CURRENT (LC_COLLATE,
-					       _NL_COLLATE_WEIGHTMB);
-      extra = (const unsigned char *) _NL_CURRENT (LC_COLLATE,
-						   _NL_COLLATE_EXTRAMB);
-      indirect = (const int32_t *) _NL_CURRENT (LC_COLLATE,
-						_NL_COLLATE_INDIRECTMB);
-      idx1 = findidx (&cp, -1);
-      if (BE (idx1 == 0 || *cp != '\0', 0))
-	/* This isn't a valid character.  */
-	return REG_ECOLLATE;
-
-      /* Build single byte matching table for this equivalence class.  */
-      len = weights[idx1 & 0xffffff];
-      for (ch = 0; ch < SBC_MAX; ++ch)
-	{
-	  char_buf[0] = ch;
-	  cp = char_buf;
-	  idx2 = findidx (&cp, 1);
-/*
-	  idx2 = table[ch];
-*/
-	  if (idx2 == 0)
-	    /* This isn't a valid character.  */
-	    continue;
-	  /* Compare only if the length matches and the collation rule
-	     index is the same.  */
-	  if (len == weights[idx2 & 0xffffff] && (idx1 >> 24) == (idx2 >> 24))
-	    {
-	      int cnt = 0;
-
-	      while (cnt <= len &&
-		     weights[(idx1 & 0xffffff) + 1 + cnt]
-		     == weights[(idx2 & 0xffffff) + 1 + cnt])
-		++cnt;
-
-	      if (cnt > len)
-		bitset_set (sbcset, ch);
-	    }
-	}
-      /* Check whether the array has enough space.  */
-      if (BE (*equiv_class_alloc == mbcset->nequiv_classes, 0))
-	{
-	  /* Not enough, realloc it.  */
-	  /* +1 in case of mbcset->nequiv_classes is 0.  */
-	  Idx new_equiv_class_alloc = 2 * mbcset->nequiv_classes + 1;
-	  /* Use realloc since the array is NULL if *alloc == 0.  */
-	  int32_t *new_equiv_classes = re_realloc (mbcset->equiv_classes,
-						   int32_t,
-						   new_equiv_class_alloc);
-	  if (BE (new_equiv_classes == NULL, 0))
-	    return REG_ESPACE;
-	  mbcset->equiv_classes = new_equiv_classes;
-	  *equiv_class_alloc = new_equiv_class_alloc;
-	}
-      mbcset->equiv_classes[mbcset->nequiv_classes++] = idx1;
-    }
-  else
-#endif /* _LIBC */
-    {
-      if (BE (strlen ((const char *) name) != 1, 0))
-	return REG_ECOLLATE;
-      bitset_set (sbcset, *name);
-    }
-  return REG_NOERROR;
-}
-
-  /* Helper function for parse_bracket_exp.
-     Build the character class which is represented by NAME.
-     The result are written to MBCSET and SBCSET.
-     CHAR_CLASS_ALLOC is the allocated size of mbcset->char_classes,
-     is a pointer argument since we may update it.  */
-
-static reg_errcode_t
-#ifdef RE_ENABLE_I18N
-build_charclass (RE_TRANSLATE_TYPE trans, bitset_t sbcset,
-		 re_charset_t *mbcset, Idx *char_class_alloc,
-		 const char *class_name, reg_syntax_t syntax)
-#else /* not RE_ENABLE_I18N */
-build_charclass (RE_TRANSLATE_TYPE trans, bitset_t sbcset,
-		 const char *class_name, reg_syntax_t syntax)
-#endif /* not RE_ENABLE_I18N */
-{
-  int i;
-  const char *name = class_name;
-
-  /* In case of REG_ICASE "upper" and "lower" match the both of
-     upper and lower cases.  */
-  if ((syntax & RE_ICASE)
-      && (strcmp (name, "upper") == 0 || strcmp (name, "lower") == 0))
-    name = "alpha";
-
-#ifdef RE_ENABLE_I18N
-  /* Check the space of the arrays.  */
-  if (BE (*char_class_alloc == mbcset->nchar_classes, 0))
-    {
-      /* Not enough, realloc it.  */
-      /* +1 in case of mbcset->nchar_classes is 0.  */
-      Idx new_char_class_alloc = 2 * mbcset->nchar_classes + 1;
-      /* Use realloc since array is NULL if *alloc == 0.  */
-      wctype_t *new_char_classes = re_realloc (mbcset->char_classes, wctype_t,
-					       new_char_class_alloc);
-      if (BE (new_char_classes == NULL, 0))
-	return REG_ESPACE;
-      mbcset->char_classes = new_char_classes;
-      *char_class_alloc = new_char_class_alloc;
-    }
-  mbcset->char_classes[mbcset->nchar_classes++] = __wctype (name);
-#endif /* RE_ENABLE_I18N */
-
-#define BUILD_CHARCLASS_LOOP(ctype_func)	\
-  do {						\
-    if (BE (trans != NULL, 0))			\
-      {						\
-	for (i = 0; i < SBC_MAX; ++i)		\
-	  if (ctype_func (i))			\
-	    bitset_set (sbcset, trans[i]);	\
-      }						\
-    else					\
-      {						\
-	for (i = 0; i < SBC_MAX; ++i)		\
-	  if (ctype_func (i))			\
-	    bitset_set (sbcset, i);		\
-      }						\
-  } while (0)
-
-  if (strcmp (name, "alnum") == 0)
-    BUILD_CHARCLASS_LOOP (isalnum);
-  else if (strcmp (name, "cntrl") == 0)
-    BUILD_CHARCLASS_LOOP (iscntrl);
-  else if (strcmp (name, "lower") == 0)
-    BUILD_CHARCLASS_LOOP (islower);
-  else if (strcmp (name, "space") == 0)
-    BUILD_CHARCLASS_LOOP (isspace);
-  else if (strcmp (name, "alpha") == 0)
-    BUILD_CHARCLASS_LOOP (isalpha);
-  else if (strcmp (name, "digit") == 0)
-    BUILD_CHARCLASS_LOOP (isdigit);
-  else if (strcmp (name, "print") == 0)
-    BUILD_CHARCLASS_LOOP (isprint);
-  else if (strcmp (name, "upper") == 0)
-    BUILD_CHARCLASS_LOOP (isupper);
-  else if (strcmp (name, "blank") == 0)
-    BUILD_CHARCLASS_LOOP (isblank);
-  else if (strcmp (name, "graph") == 0)
-    BUILD_CHARCLASS_LOOP (isgraph);
-  else if (strcmp (name, "punct") == 0)
-    BUILD_CHARCLASS_LOOP (ispunct);
-  else if (strcmp (name, "xdigit") == 0)
-    BUILD_CHARCLASS_LOOP (isxdigit);
-  else
-    return REG_ECTYPE;
-
-  return REG_NOERROR;
-}
-
-static bin_tree_t *
-build_charclass_op (re_dfa_t *dfa, RE_TRANSLATE_TYPE trans,
-		    const char *class_name,
-		    const char *extra, bool non_match,
-		    reg_errcode_t *err)
-{
-  re_bitset_ptr_t sbcset;
-#ifdef RE_ENABLE_I18N
-  re_charset_t *mbcset;
-  Idx alloc = 0;
-#endif /* not RE_ENABLE_I18N */
-  reg_errcode_t ret;
-  re_token_t br_token;
-  bin_tree_t *tree;
-
-  sbcset = (re_bitset_ptr_t) calloc (sizeof (bitset_t), 1);
-#ifdef RE_ENABLE_I18N
-  mbcset = (re_charset_t *) calloc (sizeof (re_charset_t), 1);
-#endif /* RE_ENABLE_I18N */
-
-#ifdef RE_ENABLE_I18N
-  if (BE (sbcset == NULL || mbcset == NULL, 0))
-#else /* not RE_ENABLE_I18N */
-  if (BE (sbcset == NULL, 0))
-#endif /* not RE_ENABLE_I18N */
-    {
-      *err = REG_ESPACE;
-      return NULL;
-    }
-
-  if (non_match)
-    {
-#ifdef RE_ENABLE_I18N
-      mbcset->non_match = 1;
-#endif /* not RE_ENABLE_I18N */
-    }
-
-  /* We don't care the syntax in this case.  */
-  ret = build_charclass (trans, sbcset,
-#ifdef RE_ENABLE_I18N
-			 mbcset, &alloc,
-#endif /* RE_ENABLE_I18N */
-			 class_name, 0);
-
-  if (BE (ret != REG_NOERROR, 0))
-    {
-      re_free (sbcset);
-#ifdef RE_ENABLE_I18N
-      free_charset (mbcset);
-#endif /* RE_ENABLE_I18N */
-      *err = ret;
-      return NULL;
-    }
-  /* \w match '_' also.  */
-  for (; *extra; extra++)
-    bitset_set (sbcset, *extra);
-
-  /* If it is non-matching list.  */
-  if (non_match)
-    bitset_not (sbcset);
-
-#ifdef RE_ENABLE_I18N
-  /* Ensure only single byte characters are set.  */
-  if (dfa->mb_cur_max > 1)
-    bitset_mask (sbcset, dfa->sb_char);
-#endif
-
-  /* Build a tree for simple bracket.  */
-  br_token.type = SIMPLE_BRACKET;
-  br_token.opr.sbcset = sbcset;
-  tree = create_token_tree (dfa, NULL, NULL, &br_token);
-  if (BE (tree == NULL, 0))
-    goto build_word_op_espace;
-
-#ifdef RE_ENABLE_I18N
-  if (dfa->mb_cur_max > 1)
-    {
-      bin_tree_t *mbc_tree;
-      /* Build a tree for complex bracket.  */
-      br_token.type = COMPLEX_BRACKET;
-      br_token.opr.mbcset = mbcset;
-      dfa->has_mb_node = 1;
-      mbc_tree = create_token_tree (dfa, NULL, NULL, &br_token);
-      if (BE (mbc_tree == NULL, 0))
-	goto build_word_op_espace;
-      /* Then join them by ALT node.  */
-      tree = create_tree (dfa, tree, mbc_tree, OP_ALT);
-      if (BE (mbc_tree != NULL, 1))
-	return tree;
-    }
-  else
-    {
-      free_charset (mbcset);
-      return tree;
-    }
-#else /* not RE_ENABLE_I18N */
-  return tree;
-#endif /* not RE_ENABLE_I18N */
-
- build_word_op_espace:
-  re_free (sbcset);
-#ifdef RE_ENABLE_I18N
-  free_charset (mbcset);
-#endif /* RE_ENABLE_I18N */
-  *err = REG_ESPACE;
-  return NULL;
-}
-
-/* This is intended for the expressions like "a{1,3}".
-   Fetch a number from 'input', and return the number.
-   Return REG_MISSING if the number field is empty like "{,1}".
-   Return RE_DUP_MAX + 1 if the number field is too large.
-   Return REG_ERROR if an error occurred.  */
-
-static Idx
-fetch_number (re_string_t *input, re_token_t *token, reg_syntax_t syntax)
-{
-  Idx num = REG_MISSING;
-  unsigned char c;
-  while (1)
-    {
-      fetch_token (token, input, syntax);
-      c = token->opr.c;
-      if (BE (token->type == END_OF_RE, 0))
-	return REG_ERROR;
-      if (token->type == OP_CLOSE_DUP_NUM || c == ',')
-	break;
-      num = ((token->type != CHARACTER || c < '0' || '9' < c
-	      || num == REG_ERROR)
-	     ? REG_ERROR
-	     : num == REG_MISSING
-	     ? c - '0'
-	     : MIN (RE_DUP_MAX + 1, num * 10 + c - '0'));
-    }
-  return num;
-}
-
-#ifdef RE_ENABLE_I18N
-static void
-free_charset (re_charset_t *cset)
-{
-  re_free (cset->mbchars);
-# ifdef _LIBC
-  re_free (cset->coll_syms);
-  re_free (cset->equiv_classes);
-  re_free (cset->range_starts);
-  re_free (cset->range_ends);
-# endif
-  re_free (cset->char_classes);
-  re_free (cset);
-}
-#endif /* RE_ENABLE_I18N */
-
-/* Functions for binary tree operation.  */
-
-/* Create a tree node.  */
-
-static bin_tree_t *
-create_tree (re_dfa_t *dfa, bin_tree_t *left, bin_tree_t *right,
-	     re_token_type_t type)
-{
-  re_token_t t;
-  t.type = type;
-  return create_token_tree (dfa, left, right, &t);
-}
-
-static bin_tree_t *
-create_token_tree (re_dfa_t *dfa, bin_tree_t *left, bin_tree_t *right,
-		   const re_token_t *token)
-{
-  bin_tree_t *tree;
-  if (BE (dfa->str_tree_storage_idx == BIN_TREE_STORAGE_SIZE, 0))
-    {
-      bin_tree_storage_t *storage = re_malloc (bin_tree_storage_t, 1);
-
-      if (storage == NULL)
-	return NULL;
-      storage->next = dfa->str_tree_storage;
-      dfa->str_tree_storage = storage;
-      dfa->str_tree_storage_idx = 0;
-    }
-  tree = &dfa->str_tree_storage->data[dfa->str_tree_storage_idx++];
-
-  tree->parent = NULL;
-  tree->left = left;
-  tree->right = right;
-  tree->token = *token;
-  tree->token.duplicated = 0;
-  tree->token.opt_subexp = 0;
-  tree->first = NULL;
-  tree->next = NULL;
-  tree->node_idx = REG_MISSING;
-
-  if (left != NULL)
-    left->parent = tree;
-  if (right != NULL)
-    right->parent = tree;
-  return tree;
-}
-
-/* Mark the tree SRC as an optional subexpression.
-   To be called from preorder or postorder.  */
-
-static reg_errcode_t
-mark_opt_subexp (void *extra, bin_tree_t *node)
-{
-  Idx idx = (uintptr_t) extra;
-  if (node->token.type == SUBEXP && node->token.opr.idx == idx)
-    node->token.opt_subexp = 1;
-
-  return REG_NOERROR;
-}
-
-/* Free the allocated memory inside NODE. */
-
-static void
-free_token (re_token_t *node)
-{
-#ifdef RE_ENABLE_I18N
-  if (node->type == COMPLEX_BRACKET && node->duplicated == 0)
-    free_charset (node->opr.mbcset);
-  else
-#endif /* RE_ENABLE_I18N */
-    if (node->type == SIMPLE_BRACKET && node->duplicated == 0)
-      re_free (node->opr.sbcset);
-}
-
-/* Worker function for tree walking.  Free the allocated memory inside NODE
-   and its children. */
-
-static reg_errcode_t
-free_tree (void *extra, bin_tree_t *node)
-{
-  free_token (&node->token);
-  return REG_NOERROR;
-}
-
-
-/* Duplicate the node SRC, and return new node.  This is a preorder
-   visit similar to the one implemented by the generic visitor, but
-   we need more infrastructure to maintain two parallel trees --- so,
-   it's easier to duplicate.  */
-
-static bin_tree_t *
-duplicate_tree (const bin_tree_t *root, re_dfa_t *dfa)
-{
-  const bin_tree_t *node;
-  bin_tree_t *dup_root;
-  bin_tree_t **p_new = &dup_root, *dup_node = root->parent;
-
-  for (node = root; ; )
-    {
-      /* Create a new tree and link it back to the current parent.  */
-      *p_new = create_token_tree (dfa, NULL, NULL, &node->token);
-      if (*p_new == NULL)
-	return NULL;
-      (*p_new)->parent = dup_node;
-      (*p_new)->token.duplicated = 1;
-      dup_node = *p_new;
-
-      /* Go to the left node, or up and to the right.  */
-      if (node->left)
-	{
-	  node = node->left;
-	  p_new = &dup_node->left;
-	}
-      else
-	{
-	  const bin_tree_t *prev = NULL;
-	  while (node->right == prev || node->right == NULL)
-	    {
-	      prev = node;
-	      node = node->parent;
-	      dup_node = dup_node->parent;
-	      if (!node)
-		return dup_root;
-	    }
-	  node = node->right;
-	  p_new = &dup_node->right;
-	}
-    }
-}
diff --git a/contrib/tools/bison/lib/regex.c b/contrib/tools/bison/lib/regex.c
deleted file mode 100644
index 85091669c7..0000000000
--- a/contrib/tools/bison/lib/regex.c
+++ /dev/null
@@ -1,81 +0,0 @@
-/* Extended regular expression matching and search library.
-   Copyright (C) 2002-2013 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-   Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU General Public
-   License as published by the Free Software Foundation; either
-   version 3 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   General Public License for more details.
-
-   You should have received a copy of the GNU General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-#ifndef _LIBC
-# include <config.h>
-
-# if (__GNUC__ == 4 && 6 <= __GNUC_MINOR__) || 4 < __GNUC__
-#  pragma GCC diagnostic ignored "-Wsuggest-attribute=pure"
-# endif
-# if (__GNUC__ == 4 && 3 <= __GNUC_MINOR__) || 4 < __GNUC__
-#  pragma GCC diagnostic ignored "-Wold-style-definition"
-#  pragma GCC diagnostic ignored "-Wtype-limits"
-# endif
-#endif
-
-/* Make sure no one compiles this code with a C++ compiler.  */
-#if defined __cplusplus && defined _LIBC
-# error "This is C code, use a C compiler"
-#endif
-
-#ifdef _LIBC
-/* We have to keep the namespace clean.  */
-# define regfree(preg) __regfree (preg)
-# define regexec(pr, st, nm, pm, ef) __regexec (pr, st, nm, pm, ef)
-# define regcomp(preg, pattern, cflags) __regcomp (preg, pattern, cflags)
-# define regerror(errcode, preg, errbuf, errbuf_size) \
-	__regerror(errcode, preg, errbuf, errbuf_size)
-# define re_set_registers(bu, re, nu, st, en) \
-	__re_set_registers (bu, re, nu, st, en)
-# define re_match_2(bufp, string1, size1, string2, size2, pos, regs, stop) \
-	__re_match_2 (bufp, string1, size1, string2, size2, pos, regs, stop)
-# define re_match(bufp, string, size, pos, regs) \
-	__re_match (bufp, string, size, pos, regs)
-# define re_search(bufp, string, size, startpos, range, regs) \
-	__re_search (bufp, string, size, startpos, range, regs)
-# define re_compile_pattern(pattern, length, bufp) \
-	__re_compile_pattern (pattern, length, bufp)
-# define re_set_syntax(syntax) __re_set_syntax (syntax)
-# define re_search_2(bufp, st1, s1, st2, s2, startpos, range, regs, stop) \
-	__re_search_2 (bufp, st1, s1, st2, s2, startpos, range, regs, stop)
-# define re_compile_fastmap(bufp) __re_compile_fastmap (bufp)
-
-# error #include "../locale/localeinfo.h"
-#endif
-
-/* On some systems, limits.h sets RE_DUP_MAX to a lower value than
-   GNU regex allows.  Include it before <regex.h>, which correctly
-   #undefs RE_DUP_MAX and sets it to the right value.  */
-#include <limits.h>
-
-#include <regex.h>
-#include "regex_internal.h"
-
-#include "regex_internal.c"
-#include "regcomp.c"
-#include "regexec.c"
-
-/* Binary backward compatibility.  */
-#if _LIBC
-# include <shlib-compat.h>
-# if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_3)
-link_warning (re_max_failures, "the 're_max_failures' variable is obsolete and will go away.")
-int re_max_failures = 2000;
-# endif
-#endif
diff --git a/contrib/tools/bison/lib/regex.h b/contrib/tools/bison/lib/regex.h
deleted file mode 100644
index 854c6edaf7..0000000000
--- a/contrib/tools/bison/lib/regex.h
+++ /dev/null
@@ -1,667 +0,0 @@
-/* Definitions for data structures and routines for the regular
-   expression library.
-   Copyright (C) 1985, 1989-1993, 1995-1998, 2000-2003, 2005-2013 Free Software
-   Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU General Public
-   License as published by the Free Software Foundation; either
-   version 3 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   General Public License for more details.
-
-   You should have received a copy of the GNU General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-#ifndef _REGEX_H
-#define _REGEX_H 1
-
-#include <sys/types.h>
-
-/* Allow the use in C++ code.  */
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* Define __USE_GNU to declare GNU extensions that violate the
-   POSIX name space rules.  */
-#ifdef _GNU_SOURCE
-# define __USE_GNU 1
-#endif
-
-#ifdef _REGEX_LARGE_OFFSETS
-
-/* Use types and values that are wide enough to represent signed and
-   unsigned byte offsets in memory.  This currently works only when
-   the regex code is used outside of the GNU C library; it is not yet
-   supported within glibc itself, and glibc users should not define
-   _REGEX_LARGE_OFFSETS.  */
-
-/* The type of nonnegative object indexes.  Traditionally, GNU regex
-   uses 'int' for these.  Code that uses __re_idx_t should work
-   regardless of whether the type is signed.  */
-typedef size_t __re_idx_t;
-
-/* The type of object sizes.  */
-typedef size_t __re_size_t;
-
-/* The type of object sizes, in places where the traditional code
-   uses unsigned long int.  */
-typedef size_t __re_long_size_t;
-
-#else
-
-/* The traditional GNU regex implementation mishandles strings longer
-   than INT_MAX.  */
-typedef int __re_idx_t;
-typedef unsigned int __re_size_t;
-typedef unsigned long int __re_long_size_t;
-
-#endif
-
-/* The following two types have to be signed and unsigned integer type
-   wide enough to hold a value of a pointer.  For most ANSI compilers
-   ptrdiff_t and size_t should be likely OK.  Still size of these two
-   types is 2 for Microsoft C.  Ugh... */
-typedef long int s_reg_t;
-typedef unsigned long int active_reg_t;
-
-/* The following bits are used to determine the regexp syntax we
-   recognize.  The set/not-set meanings are chosen so that Emacs syntax
-   remains the value 0.  The bits are given in alphabetical order, and
-   the definitions shifted by one from the previous bit; thus, when we
-   add or remove a bit, only one other definition need change.  */
-typedef unsigned long int reg_syntax_t;
-
-#ifdef __USE_GNU
-/* If this bit is not set, then \ inside a bracket expression is literal.
-   If set, then such a \ quotes the following character.  */
-# define RE_BACKSLASH_ESCAPE_IN_LISTS ((unsigned long int) 1)
-
-/* If this bit is not set, then + and ? are operators, and \+ and \? are
-     literals.
-   If set, then \+ and \? are operators and + and ? are literals.  */
-# define RE_BK_PLUS_QM (RE_BACKSLASH_ESCAPE_IN_LISTS << 1)
-
-/* If this bit is set, then character classes are supported.  They are:
-     [:alpha:], [:upper:], [:lower:],  [:digit:], [:alnum:], [:xdigit:],
-     [:space:], [:print:], [:punct:], [:graph:], and [:cntrl:].
-   If not set, then character classes are not supported.  */
-# define RE_CHAR_CLASSES (RE_BK_PLUS_QM << 1)
-
-/* If this bit is set, then ^ and $ are always anchors (outside bracket
-     expressions, of course).
-   If this bit is not set, then it depends:
-	^  is an anchor if it is at the beginning of a regular
-	   expression or after an open-group or an alternation operator;
-	$  is an anchor if it is at the end of a regular expression, or
-	   before a close-group or an alternation operator.
-
-   This bit could be (re)combined with RE_CONTEXT_INDEP_OPS, because
-   POSIX draft 11.2 says that * etc. in leading positions is undefined.
-   We already implemented a previous draft which made those constructs
-   invalid, though, so we haven't changed the code back.  */
-# define RE_CONTEXT_INDEP_ANCHORS (RE_CHAR_CLASSES << 1)
-
-/* If this bit is set, then special characters are always special
-     regardless of where they are in the pattern.
-   If this bit is not set, then special characters are special only in
-     some contexts; otherwise they are ordinary.  Specifically,
-     * + ? and intervals are only special when not after the beginning,
-     open-group, or alternation operator.  */
-# define RE_CONTEXT_INDEP_OPS (RE_CONTEXT_INDEP_ANCHORS << 1)
-
-/* If this bit is set, then *, +, ?, and { cannot be first in an re or
-     immediately after an alternation or begin-group operator.  */
-# define RE_CONTEXT_INVALID_OPS (RE_CONTEXT_INDEP_OPS << 1)
-
-/* If this bit is set, then . matches newline.
-   If not set, then it doesn't.  */
-# define RE_DOT_NEWLINE (RE_CONTEXT_INVALID_OPS << 1)
-
-/* If this bit is set, then . doesn't match NUL.
-   If not set, then it does.  */
-# define RE_DOT_NOT_NULL (RE_DOT_NEWLINE << 1)
-
-/* If this bit is set, nonmatching lists [^...] do not match newline.
-   If not set, they do.  */
-# define RE_HAT_LISTS_NOT_NEWLINE (RE_DOT_NOT_NULL << 1)
-
-/* If this bit is set, either \{...\} or {...} defines an
-     interval, depending on RE_NO_BK_BRACES.
-   If not set, \{, \}, {, and } are literals.  */
-# define RE_INTERVALS (RE_HAT_LISTS_NOT_NEWLINE << 1)
-
-/* If this bit is set, +, ? and | aren't recognized as operators.
-   If not set, they are.  */
-# define RE_LIMITED_OPS (RE_INTERVALS << 1)
-
-/* If this bit is set, newline is an alternation operator.
-   If not set, newline is literal.  */
-# define RE_NEWLINE_ALT (RE_LIMITED_OPS << 1)
-
-/* If this bit is set, then '{...}' defines an interval, and \{ and \}
-     are literals.
-  If not set, then '\{...\}' defines an interval.  */
-# define RE_NO_BK_BRACES (RE_NEWLINE_ALT << 1)
-
-/* If this bit is set, (...) defines a group, and \( and \) are literals.
-   If not set, \(...\) defines a group, and ( and ) are literals.  */
-# define RE_NO_BK_PARENS (RE_NO_BK_BRACES << 1)
-
-/* If this bit is set, then \<digit> matches <digit>.
-   If not set, then \<digit> is a back-reference.  */
-# define RE_NO_BK_REFS (RE_NO_BK_PARENS << 1)
-
-/* If this bit is set, then | is an alternation operator, and \| is literal.
-   If not set, then \| is an alternation operator, and | is literal.  */
-# define RE_NO_BK_VBAR (RE_NO_BK_REFS << 1)
-
-/* If this bit is set, then an ending range point collating higher
-     than the starting range point, as in [z-a], is invalid.
-   If not set, then when ending range point collates higher than the
-     starting range point, the range is ignored.  */
-# define RE_NO_EMPTY_RANGES (RE_NO_BK_VBAR << 1)
-
-/* If this bit is set, then an unmatched ) is ordinary.
-   If not set, then an unmatched ) is invalid.  */
-# define RE_UNMATCHED_RIGHT_PAREN_ORD (RE_NO_EMPTY_RANGES << 1)
-
-/* If this bit is set, succeed as soon as we match the whole pattern,
-   without further backtracking.  */
-# define RE_NO_POSIX_BACKTRACKING (RE_UNMATCHED_RIGHT_PAREN_ORD << 1)
-
-/* If this bit is set, do not process the GNU regex operators.
-   If not set, then the GNU regex operators are recognized. */
-# define RE_NO_GNU_OPS (RE_NO_POSIX_BACKTRACKING << 1)
-
-/* If this bit is set, turn on internal regex debugging.
-   If not set, and debugging was on, turn it off.
-   This only works if regex.c is compiled -DDEBUG.
-   We define this bit always, so that all that's needed to turn on
-   debugging is to recompile regex.c; the calling code can always have
-   this bit set, and it won't affect anything in the normal case. */
-# define RE_DEBUG (RE_NO_GNU_OPS << 1)
-
-/* If this bit is set, a syntactically invalid interval is treated as
-   a string of ordinary characters.  For example, the ERE 'a{1' is
-   treated as 'a\{1'.  */
-# define RE_INVALID_INTERVAL_ORD (RE_DEBUG << 1)
-
-/* If this bit is set, then ignore case when matching.
-   If not set, then case is significant.  */
-# define RE_ICASE (RE_INVALID_INTERVAL_ORD << 1)
-
-/* This bit is used internally like RE_CONTEXT_INDEP_ANCHORS but only
-   for ^, because it is difficult to scan the regex backwards to find
-   whether ^ should be special.  */
-# define RE_CARET_ANCHORS_HERE (RE_ICASE << 1)
-
-/* If this bit is set, then \{ cannot be first in a regex or
-   immediately after an alternation, open-group or \} operator.  */
-# define RE_CONTEXT_INVALID_DUP (RE_CARET_ANCHORS_HERE << 1)
-
-/* If this bit is set, then no_sub will be set to 1 during
-   re_compile_pattern.  */
-# define RE_NO_SUB (RE_CONTEXT_INVALID_DUP << 1)
-#endif
-
-/* This global variable defines the particular regexp syntax to use (for
-   some interfaces).  When a regexp is compiled, the syntax used is
-   stored in the pattern buffer, so changing this does not affect
-   already-compiled regexps.  */
-extern reg_syntax_t re_syntax_options;
-
-#ifdef __USE_GNU
-/* Define combinations of the above bits for the standard possibilities.
-   (The [[[ comments delimit what gets put into the Texinfo file, so
-   don't delete them!)  */
-/* [[[begin syntaxes]]] */
-# define RE_SYNTAX_EMACS 0
-
-# define RE_SYNTAX_AWK							\
-  (RE_BACKSLASH_ESCAPE_IN_LISTS   | RE_DOT_NOT_NULL			\
-   | RE_NO_BK_PARENS              | RE_NO_BK_REFS			\
-   | RE_NO_BK_VBAR                | RE_NO_EMPTY_RANGES			\
-   | RE_DOT_NEWLINE		  | RE_CONTEXT_INDEP_ANCHORS		\
-   | RE_CHAR_CLASSES							\
-   | RE_UNMATCHED_RIGHT_PAREN_ORD | RE_NO_GNU_OPS)
-
-# define RE_SYNTAX_GNU_AWK						\
-  ((RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS		\
-    | RE_INVALID_INTERVAL_ORD)						\
-   & ~(RE_DOT_NOT_NULL | RE_CONTEXT_INDEP_OPS				\
-      | RE_CONTEXT_INVALID_OPS ))
-
-# define RE_SYNTAX_POSIX_AWK						\
-  (RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS		\
-   | RE_INTERVALS	    | RE_NO_GNU_OPS				\
-   | RE_INVALID_INTERVAL_ORD)
-
-# define RE_SYNTAX_GREP							\
-  (RE_BK_PLUS_QM              | RE_CHAR_CLASSES				\
-   | RE_HAT_LISTS_NOT_NEWLINE | RE_INTERVALS				\
-   | RE_NEWLINE_ALT)
-
-# define RE_SYNTAX_EGREP						\
-  (RE_CHAR_CLASSES        | RE_CONTEXT_INDEP_ANCHORS			\
-   | RE_CONTEXT_INDEP_OPS | RE_HAT_LISTS_NOT_NEWLINE			\
-   | RE_NEWLINE_ALT       | RE_NO_BK_PARENS				\
-   | RE_NO_BK_VBAR)
-
-# define RE_SYNTAX_POSIX_EGREP						\
-  (RE_SYNTAX_EGREP | RE_INTERVALS | RE_NO_BK_BRACES			\
-   | RE_INVALID_INTERVAL_ORD)
-
-/* P1003.2/D11.2, section 4.20.7.1, lines 5078ff.  */
-# define RE_SYNTAX_ED RE_SYNTAX_POSIX_BASIC
-
-# define RE_SYNTAX_SED RE_SYNTAX_POSIX_BASIC
-
-/* Syntax bits common to both basic and extended POSIX regex syntax.  */
-# define _RE_SYNTAX_POSIX_COMMON					\
-  (RE_CHAR_CLASSES | RE_DOT_NEWLINE      | RE_DOT_NOT_NULL		\
-   | RE_INTERVALS  | RE_NO_EMPTY_RANGES)
-
-# define RE_SYNTAX_POSIX_BASIC						\
-  (_RE_SYNTAX_POSIX_COMMON | RE_BK_PLUS_QM | RE_CONTEXT_INVALID_DUP)
-
-/* Differs from ..._POSIX_BASIC only in that RE_BK_PLUS_QM becomes
-   RE_LIMITED_OPS, i.e., \? \+ \| are not recognized.  Actually, this
-   isn't minimal, since other operators, such as \`, aren't disabled.  */
-# define RE_SYNTAX_POSIX_MINIMAL_BASIC					\
-  (_RE_SYNTAX_POSIX_COMMON | RE_LIMITED_OPS)
-
-# define RE_SYNTAX_POSIX_EXTENDED					\
-  (_RE_SYNTAX_POSIX_COMMON  | RE_CONTEXT_INDEP_ANCHORS			\
-   | RE_CONTEXT_INDEP_OPS   | RE_NO_BK_BRACES				\
-   | RE_NO_BK_PARENS        | RE_NO_BK_VBAR				\
-   | RE_CONTEXT_INVALID_OPS | RE_UNMATCHED_RIGHT_PAREN_ORD)
-
-/* Differs from ..._POSIX_EXTENDED in that RE_CONTEXT_INDEP_OPS is
-   removed and RE_NO_BK_REFS is added.  */
-# define RE_SYNTAX_POSIX_MINIMAL_EXTENDED				\
-  (_RE_SYNTAX_POSIX_COMMON  | RE_CONTEXT_INDEP_ANCHORS			\
-   | RE_CONTEXT_INVALID_OPS | RE_NO_BK_BRACES				\
-   | RE_NO_BK_PARENS        | RE_NO_BK_REFS				\
-   | RE_NO_BK_VBAR	    | RE_UNMATCHED_RIGHT_PAREN_ORD)
-/* [[[end syntaxes]]] */
-
-/* Maximum number of duplicates an interval can allow.  POSIX-conforming
-   systems might define this in <limits.h>, but we want our
-   value, so remove any previous define.  */
-# ifdef _REGEX_INCLUDE_LIMITS_H
-#  include <limits.h>
-# endif
-# ifdef RE_DUP_MAX
-#  undef RE_DUP_MAX
-# endif
-
-/* RE_DUP_MAX is 2**15 - 1 because an earlier implementation stored
-   the counter as a 2-byte signed integer.  This is no longer true, so
-   RE_DUP_MAX could be increased to (INT_MAX / 10 - 1), or to
-   ((SIZE_MAX - 9) / 10) if _REGEX_LARGE_OFFSETS is defined.
-   However, there would be a huge performance problem if someone
-   actually used a pattern like a\{214748363\}, so RE_DUP_MAX retains
-   its historical value.  */
-# define RE_DUP_MAX (0x7fff)
-#endif
-
-
-/* POSIX 'cflags' bits (i.e., information for 'regcomp').  */
-
-/* If this bit is set, then use extended regular expression syntax.
-   If not set, then use basic regular expression syntax.  */
-#define REG_EXTENDED 1
-
-/* If this bit is set, then ignore case when matching.
-   If not set, then case is significant.  */
-#define REG_ICASE (1 << 1)
-
-/* If this bit is set, then anchors do not match at newline
-     characters in the string.
-   If not set, then anchors do match at newlines.  */
-#define REG_NEWLINE (1 << 2)
-
-/* If this bit is set, then report only success or fail in regexec.
-   If not set, then returns differ between not matching and errors.  */
-#define REG_NOSUB (1 << 3)
-
-
-/* POSIX 'eflags' bits (i.e., information for regexec).  */
-
-/* If this bit is set, then the beginning-of-line operator doesn't match
-     the beginning of the string (presumably because it's not the
-     beginning of a line).
-   If not set, then the beginning-of-line operator does match the
-     beginning of the string.  */
-#define REG_NOTBOL 1
-
-/* Like REG_NOTBOL, except for the end-of-line.  */
-#define REG_NOTEOL (1 << 1)
-
-/* Use PMATCH[0] to delimit the start and end of the search in the
-   buffer.  */
-#define REG_STARTEND (1 << 2)
-
-
-/* If any error codes are removed, changed, or added, update the
-   '__re_error_msgid' table in regcomp.c.  */
-
-typedef enum
-{
-  _REG_ENOSYS = -1,	/* This will never happen for this implementation.  */
-  _REG_NOERROR = 0,	/* Success.  */
-  _REG_NOMATCH,		/* Didn't find a match (for regexec).  */
-
-  /* POSIX regcomp return error codes.  (In the order listed in the
-     standard.)  */
-  _REG_BADPAT,		/* Invalid pattern.  */
-  _REG_ECOLLATE,	/* Invalid collating element.  */
-  _REG_ECTYPE,		/* Invalid character class name.  */
-  _REG_EESCAPE,		/* Trailing backslash.  */
-  _REG_ESUBREG,		/* Invalid back reference.  */
-  _REG_EBRACK,		/* Unmatched left bracket.  */
-  _REG_EPAREN,		/* Parenthesis imbalance.  */
-  _REG_EBRACE,		/* Unmatched \{.  */
-  _REG_BADBR,		/* Invalid contents of \{\}.  */
-  _REG_ERANGE,		/* Invalid range end.  */
-  _REG_ESPACE,		/* Ran out of memory.  */
-  _REG_BADRPT,		/* No preceding re for repetition op.  */
-
-  /* Error codes we've added.  */
-  _REG_EEND,		/* Premature end.  */
-  _REG_ESIZE,		/* Too large (e.g., repeat count too large).  */
-  _REG_ERPAREN		/* Unmatched ) or \); not returned from regcomp.  */
-} reg_errcode_t;
-
-#if defined _XOPEN_SOURCE || defined __USE_XOPEN2K
-# define REG_ENOSYS	_REG_ENOSYS
-#endif
-#define REG_NOERROR	_REG_NOERROR
-#define REG_NOMATCH	_REG_NOMATCH
-#define REG_BADPAT	_REG_BADPAT
-#define REG_ECOLLATE	_REG_ECOLLATE
-#define REG_ECTYPE	_REG_ECTYPE
-#define REG_EESCAPE	_REG_EESCAPE
-#define REG_ESUBREG	_REG_ESUBREG
-#define REG_EBRACK	_REG_EBRACK
-#define REG_EPAREN	_REG_EPAREN
-#define REG_EBRACE	_REG_EBRACE
-#define REG_BADBR	_REG_BADBR
-#define REG_ERANGE	_REG_ERANGE
-#define REG_ESPACE	_REG_ESPACE
-#define REG_BADRPT	_REG_BADRPT
-#define REG_EEND	_REG_EEND
-#define REG_ESIZE	_REG_ESIZE
-#define REG_ERPAREN	_REG_ERPAREN
-
-/* This data structure represents a compiled pattern.  Before calling
-   the pattern compiler, the fields 'buffer', 'allocated', 'fastmap',
-   and 'translate' can be set.  After the pattern has been compiled,
-   the fields 're_nsub', 'not_bol' and 'not_eol' are available.  All
-   other fields are private to the regex routines.  */
-
-#ifndef RE_TRANSLATE_TYPE
-# define __RE_TRANSLATE_TYPE unsigned char *
-# ifdef __USE_GNU
-#  define RE_TRANSLATE_TYPE __RE_TRANSLATE_TYPE
-# endif
-#endif
-
-#ifdef __USE_GNU
-# define __REPB_PREFIX(name) name
-#else
-# define __REPB_PREFIX(name) __##name
-#endif
-
-struct re_pattern_buffer
-{
-  /* Space that holds the compiled pattern.  The type
-     'struct re_dfa_t' is private and is not declared here.  */
-  struct re_dfa_t *__REPB_PREFIX(buffer);
-
-  /* Number of bytes to which 'buffer' points.  */
-  __re_long_size_t __REPB_PREFIX(allocated);
-
-  /* Number of bytes actually used in 'buffer'.  */
-  __re_long_size_t __REPB_PREFIX(used);
-
-  /* Syntax setting with which the pattern was compiled.  */
-  reg_syntax_t __REPB_PREFIX(syntax);
-
-  /* Pointer to a fastmap, if any, otherwise zero.  re_search uses the
-     fastmap, if there is one, to skip over impossible starting points
-     for matches.  */
-  char *__REPB_PREFIX(fastmap);
-
-  /* Either a translate table to apply to all characters before
-     comparing them, or zero for no translation.  The translation is
-     applied to a pattern when it is compiled and to a string when it
-     is matched.  */
-  __RE_TRANSLATE_TYPE __REPB_PREFIX(translate);
-
-  /* Number of subexpressions found by the compiler.  */
-  size_t re_nsub;
-
-  /* Zero if this pattern cannot match the empty string, one else.
-     Well, in truth it's used only in 're_search_2', to see whether or
-     not we should use the fastmap, so we don't set this absolutely
-     perfectly; see 're_compile_fastmap' (the "duplicate" case).  */
-  unsigned __REPB_PREFIX(can_be_null) : 1;
-
-  /* If REGS_UNALLOCATED, allocate space in the 'regs' structure
-     for 'max (RE_NREGS, re_nsub + 1)' groups.
-     If REGS_REALLOCATE, reallocate space if necessary.
-     If REGS_FIXED, use what's there.  */
-#ifdef __USE_GNU
-# define REGS_UNALLOCATED 0
-# define REGS_REALLOCATE 1
-# define REGS_FIXED 2
-#endif
-  unsigned __REPB_PREFIX(regs_allocated) : 2;
-
-  /* Set to zero when 're_compile_pattern' compiles a pattern; set to
-     one by 're_compile_fastmap' if it updates the fastmap.  */
-  unsigned __REPB_PREFIX(fastmap_accurate) : 1;
-
-  /* If set, 're_match_2' does not return information about
-     subexpressions.  */
-  unsigned __REPB_PREFIX(no_sub) : 1;
-
-  /* If set, a beginning-of-line anchor doesn't match at the beginning
-     of the string.  */
-  unsigned __REPB_PREFIX(not_bol) : 1;
-
-  /* Similarly for an end-of-line anchor.  */
-  unsigned __REPB_PREFIX(not_eol) : 1;
-
-  /* If true, an anchor at a newline matches.  */
-  unsigned __REPB_PREFIX(newline_anchor) : 1;
-};
-
-typedef struct re_pattern_buffer regex_t;
-
-/* Type for byte offsets within the string.  POSIX mandates this.  */
-#ifdef _REGEX_LARGE_OFFSETS
-/* POSIX 1003.1-2008 requires that regoff_t be at least as wide as
-   ptrdiff_t and ssize_t.  We don't know of any hosts where ptrdiff_t
-   is wider than ssize_t, so ssize_t is safe.  */
-typedef ssize_t regoff_t;
-#else
-/* The traditional GNU regex implementation mishandles strings longer
-   than INT_MAX.  */
-typedef int regoff_t;
-#endif
-
-
-#ifdef __USE_GNU
-/* This is the structure we store register match data in.  See
-   regex.texinfo for a full description of what registers match.  */
-struct re_registers
-{
-  __re_size_t num_regs;
-  regoff_t *start;
-  regoff_t *end;
-};
-
-
-/* If 'regs_allocated' is REGS_UNALLOCATED in the pattern buffer,
-   're_match_2' returns information about at least this many registers
-   the first time a 'regs' structure is passed.  */
-# ifndef RE_NREGS
-#  define RE_NREGS 30
-# endif
-#endif
-
-
-/* POSIX specification for registers.  Aside from the different names than
-   're_registers', POSIX uses an array of structures, instead of a
-   structure of arrays.  */
-typedef struct
-{
-  regoff_t rm_so;  /* Byte offset from string's start to substring's start.  */
-  regoff_t rm_eo;  /* Byte offset from string's start to substring's end.  */
-} regmatch_t;
-
-/* Declarations for routines.  */
-
-#ifdef __USE_GNU
-/* Sets the current default syntax to SYNTAX, and return the old syntax.
-   You can also simply assign to the 're_syntax_options' variable.  */
-extern reg_syntax_t re_set_syntax (reg_syntax_t __syntax);
-
-/* Compile the regular expression PATTERN, with length LENGTH
-   and syntax given by the global 're_syntax_options', into the buffer
-   BUFFER.  Return NULL if successful, and an error string if not.
-
-   To free the allocated storage, you must call 'regfree' on BUFFER.
-   Note that the translate table must either have been initialised by
-   'regcomp', with a malloc'ed value, or set to NULL before calling
-   'regfree'.  */
-extern const char *re_compile_pattern (const char *__pattern, size_t __length,
-				       struct re_pattern_buffer *__buffer);
-
-
-/* Compile a fastmap for the compiled pattern in BUFFER; used to
-   accelerate searches.  Return 0 if successful and -2 if was an
-   internal error.  */
-extern int re_compile_fastmap (struct re_pattern_buffer *__buffer);
-
-
-/* Search in the string STRING (with length LENGTH) for the pattern
-   compiled into BUFFER.  Start searching at position START, for RANGE
-   characters.  Return the starting position of the match, -1 for no
-   match, or -2 for an internal error.  Also return register
-   information in REGS (if REGS and BUFFER->no_sub are nonzero).  */
-extern regoff_t re_search (struct re_pattern_buffer *__buffer,
-			   const char *__string, __re_idx_t __length,
-			   __re_idx_t __start, regoff_t __range,
-			   struct re_registers *__regs);
-
-
-/* Like 're_search', but search in the concatenation of STRING1 and
-   STRING2.  Also, stop searching at index START + STOP.  */
-extern regoff_t re_search_2 (struct re_pattern_buffer *__buffer,
-			     const char *__string1, __re_idx_t __length1,
-			     const char *__string2, __re_idx_t __length2,
-			     __re_idx_t __start, regoff_t __range,
-			     struct re_registers *__regs,
-			     __re_idx_t __stop);
-
-
-/* Like 're_search', but return how many characters in STRING the regexp
-   in BUFFER matched, starting at position START.  */
-extern regoff_t re_match (struct re_pattern_buffer *__buffer,
-			  const char *__string, __re_idx_t __length,
-			  __re_idx_t __start, struct re_registers *__regs);
-
-
-/* Relates to 're_match' as 're_search_2' relates to 're_search'.  */
-extern regoff_t re_match_2 (struct re_pattern_buffer *__buffer,
-			    const char *__string1, __re_idx_t __length1,
-			    const char *__string2, __re_idx_t __length2,
-			    __re_idx_t __start, struct re_registers *__regs,
-			    __re_idx_t __stop);
-
-
-/* Set REGS to hold NUM_REGS registers, storing them in STARTS and
-   ENDS.  Subsequent matches using BUFFER and REGS will use this memory
-   for recording register information.  STARTS and ENDS must be
-   allocated with malloc, and must each be at least 'NUM_REGS * sizeof
-   (regoff_t)' bytes long.
-
-   If NUM_REGS == 0, then subsequent matches should allocate their own
-   register data.
-
-   Unless this function is called, the first search or match using
-   BUFFER will allocate its own register data, without
-   freeing the old data.  */
-extern void re_set_registers (struct re_pattern_buffer *__buffer,
-			      struct re_registers *__regs,
-			      __re_size_t __num_regs,
-			      regoff_t *__starts, regoff_t *__ends);
-#endif	/* Use GNU */
-
-#if defined _REGEX_RE_COMP || (defined _LIBC && defined __USE_BSD)
-# ifndef _CRAY
-/* 4.2 bsd compatibility.  */
-extern char *re_comp (const char *);
-extern int re_exec (const char *);
-# endif
-#endif
-
-/* GCC 2.95 and later have "__restrict"; C99 compilers have
-   "restrict", and "configure" may have defined "restrict".
-   Other compilers use __restrict, __restrict__, and _Restrict, and
-   'configure' might #define 'restrict' to those words, so pick a
-   different name.  */
-#ifndef _Restrict_
-# if 199901L <= __STDC_VERSION__
-#  define _Restrict_ restrict
-# elif 2 < __GNUC__ || (2 == __GNUC__ && 95 <= __GNUC_MINOR__)
-#  define _Restrict_ __restrict
-# else
-#  define _Restrict_
-# endif
-#endif
-/* gcc 3.1 and up support the [restrict] syntax.  Don't trust
-   sys/cdefs.h's definition of __restrict_arr, though, as it
-   mishandles gcc -ansi -pedantic.  */
-#ifndef _Restrict_arr_
-# if ((199901L <= __STDC_VERSION__					\
-       || ((3 < __GNUC__ || (3 == __GNUC__ && 1 <= __GNUC_MINOR__))	\
-	   && !defined __STRICT_ANSI__))					\
-      && !defined __GNUG__)
-#  define _Restrict_arr_ _Restrict_
-# else
-#  define _Restrict_arr_
-# endif
-#endif
-
-/* POSIX compatibility.  */
-extern int regcomp (regex_t *_Restrict_ __preg,
-		    const char *_Restrict_ __pattern,
-		    int __cflags);
-
-extern int regexec (const regex_t *_Restrict_ __preg,
-		    const char *_Restrict_ __string, size_t __nmatch,
-		    regmatch_t __pmatch[_Restrict_arr_],
-		    int __eflags);
-
-extern size_t regerror (int __errcode, const regex_t *_Restrict_ __preg,
-			char *_Restrict_ __errbuf, size_t __errbuf_size);
-
-extern void regfree (regex_t *__preg);
-
-
-#ifdef __cplusplus
-}
-#endif	/* C++ */
-
-#endif /* regex.h */
diff --git a/contrib/tools/bison/lib/regex_internal.c b/contrib/tools/bison/lib/regex_internal.c
deleted file mode 100644
index 899b0ae67e..0000000000
--- a/contrib/tools/bison/lib/regex_internal.c
+++ /dev/null
@@ -1,1741 +0,0 @@
-/* Extended regular expression matching and search library.
-   Copyright (C) 2002-2013 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-   Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU General Public
-   License as published by the Free Software Foundation; either
-   version 3 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   General Public License for more details.
-
-   You should have received a copy of the GNU General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-static void re_string_construct_common (const char *str, Idx len,
-					re_string_t *pstr,
-					RE_TRANSLATE_TYPE trans, bool icase,
-					const re_dfa_t *dfa) internal_function;
-static re_dfastate_t *create_ci_newstate (const re_dfa_t *dfa,
-					  const re_node_set *nodes,
-					  re_hashval_t hash) internal_function;
-static re_dfastate_t *create_cd_newstate (const re_dfa_t *dfa,
-					  const re_node_set *nodes,
-					  unsigned int context,
-					  re_hashval_t hash) internal_function;
-
-/* Functions for string operation.  */
-
-/* This function allocate the buffers.  It is necessary to call
-   re_string_reconstruct before using the object.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-re_string_allocate (re_string_t *pstr, const char *str, Idx len, Idx init_len,
-		    RE_TRANSLATE_TYPE trans, bool icase, const re_dfa_t *dfa)
-{
-  reg_errcode_t ret;
-  Idx init_buf_len;
-
-  /* Ensure at least one character fits into the buffers.  */
-  if (init_len < dfa->mb_cur_max)
-    init_len = dfa->mb_cur_max;
-  init_buf_len = (len + 1 < init_len) ? len + 1: init_len;
-  re_string_construct_common (str, len, pstr, trans, icase, dfa);
-
-  ret = re_string_realloc_buffers (pstr, init_buf_len);
-  if (BE (ret != REG_NOERROR, 0))
-    return ret;
-
-  pstr->word_char = dfa->word_char;
-  pstr->word_ops_used = dfa->word_ops_used;
-  pstr->mbs = pstr->mbs_allocated ? pstr->mbs : (unsigned char *) str;
-  pstr->valid_len = (pstr->mbs_allocated || dfa->mb_cur_max > 1) ? 0 : len;
-  pstr->valid_raw_len = pstr->valid_len;
-  return REG_NOERROR;
-}
-
-/* This function allocate the buffers, and initialize them.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-re_string_construct (re_string_t *pstr, const char *str, Idx len,
-		     RE_TRANSLATE_TYPE trans, bool icase, const re_dfa_t *dfa)
-{
-  reg_errcode_t ret;
-  memset (pstr, '\0', sizeof (re_string_t));
-  re_string_construct_common (str, len, pstr, trans, icase, dfa);
-
-  if (len > 0)
-    {
-      ret = re_string_realloc_buffers (pstr, len + 1);
-      if (BE (ret != REG_NOERROR, 0))
-	return ret;
-    }
-  pstr->mbs = pstr->mbs_allocated ? pstr->mbs : (unsigned char *) str;
-
-  if (icase)
-    {
-#ifdef RE_ENABLE_I18N
-      if (dfa->mb_cur_max > 1)
-	{
-	  while (1)
-	    {
-	      ret = build_wcs_upper_buffer (pstr);
-	      if (BE (ret != REG_NOERROR, 0))
-		return ret;
-	      if (pstr->valid_raw_len >= len)
-		break;
-	      if (pstr->bufs_len > pstr->valid_len + dfa->mb_cur_max)
-		break;
-	      ret = re_string_realloc_buffers (pstr, pstr->bufs_len * 2);
-	      if (BE (ret != REG_NOERROR, 0))
-		return ret;
-	    }
-	}
-      else
-#endif /* RE_ENABLE_I18N  */
-	build_upper_buffer (pstr);
-    }
-  else
-    {
-#ifdef RE_ENABLE_I18N
-      if (dfa->mb_cur_max > 1)
-	build_wcs_buffer (pstr);
-      else
-#endif /* RE_ENABLE_I18N  */
-	{
-	  if (trans != NULL)
-	    re_string_translate_buffer (pstr);
-	  else
-	    {
-	      pstr->valid_len = pstr->bufs_len;
-	      pstr->valid_raw_len = pstr->bufs_len;
-	    }
-	}
-    }
-
-  return REG_NOERROR;
-}
-
-/* Helper functions for re_string_allocate, and re_string_construct.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-re_string_realloc_buffers (re_string_t *pstr, Idx new_buf_len)
-{
-#ifdef RE_ENABLE_I18N
-  if (pstr->mb_cur_max > 1)
-    {
-      wint_t *new_wcs;
-
-      /* Avoid overflow in realloc.  */
-      const size_t max_object_size = MAX (sizeof (wint_t), sizeof (Idx));
-      if (BE (MIN (IDX_MAX, SIZE_MAX / max_object_size) < new_buf_len, 0))
-	return REG_ESPACE;
-
-      new_wcs = re_realloc (pstr->wcs, wint_t, new_buf_len);
-      if (BE (new_wcs == NULL, 0))
-	return REG_ESPACE;
-      pstr->wcs = new_wcs;
-      if (pstr->offsets != NULL)
-	{
-	  Idx *new_offsets = re_realloc (pstr->offsets, Idx, new_buf_len);
-	  if (BE (new_offsets == NULL, 0))
-	    return REG_ESPACE;
-	  pstr->offsets = new_offsets;
-	}
-    }
-#endif /* RE_ENABLE_I18N  */
-  if (pstr->mbs_allocated)
-    {
-      unsigned char *new_mbs = re_realloc (pstr->mbs, unsigned char,
-					   new_buf_len);
-      if (BE (new_mbs == NULL, 0))
-	return REG_ESPACE;
-      pstr->mbs = new_mbs;
-    }
-  pstr->bufs_len = new_buf_len;
-  return REG_NOERROR;
-}
-
-
-static void
-internal_function
-re_string_construct_common (const char *str, Idx len, re_string_t *pstr,
-			    RE_TRANSLATE_TYPE trans, bool icase,
-			    const re_dfa_t *dfa)
-{
-  pstr->raw_mbs = (const unsigned char *) str;
-  pstr->len = len;
-  pstr->raw_len = len;
-  pstr->trans = trans;
-  pstr->icase = icase;
-  pstr->mbs_allocated = (trans != NULL || icase);
-  pstr->mb_cur_max = dfa->mb_cur_max;
-  pstr->is_utf8 = dfa->is_utf8;
-  pstr->map_notascii = dfa->map_notascii;
-  pstr->stop = pstr->len;
-  pstr->raw_stop = pstr->stop;
-}
-
-#ifdef RE_ENABLE_I18N
-
-/* Build wide character buffer PSTR->WCS.
-   If the byte sequence of the string are:
-     <mb1>(0), <mb1>(1), <mb2>(0), <mb2>(1), <sb3>
-   Then wide character buffer will be:
-     <wc1>   , WEOF    , <wc2>   , WEOF    , <wc3>
-   We use WEOF for padding, they indicate that the position isn't
-   a first byte of a multibyte character.
-
-   Note that this function assumes PSTR->VALID_LEN elements are already
-   built and starts from PSTR->VALID_LEN.  */
-
-static void
-internal_function
-build_wcs_buffer (re_string_t *pstr)
-{
-#ifdef _LIBC
-  unsigned char buf[MB_LEN_MAX];
-  assert (MB_LEN_MAX >= pstr->mb_cur_max);
-#else
-  unsigned char buf[64];
-#endif
-  mbstate_t prev_st;
-  Idx byte_idx, end_idx, remain_len;
-  size_t mbclen;
-
-  /* Build the buffers from pstr->valid_len to either pstr->len or
-     pstr->bufs_len.  */
-  end_idx = (pstr->bufs_len > pstr->len) ? pstr->len : pstr->bufs_len;
-  for (byte_idx = pstr->valid_len; byte_idx < end_idx;)
-    {
-      wchar_t wc;
-      const char *p;
-
-      remain_len = end_idx - byte_idx;
-      prev_st = pstr->cur_state;
-      /* Apply the translation if we need.  */
-      if (BE (pstr->trans != NULL, 0))
-	{
-	  int i, ch;
-
-	  for (i = 0; i < pstr->mb_cur_max && i < remain_len; ++i)
-	    {
-	      ch = pstr->raw_mbs [pstr->raw_mbs_idx + byte_idx + i];
-	      buf[i] = pstr->mbs[byte_idx + i] = pstr->trans[ch];
-	    }
-	  p = (const char *) buf;
-	}
-      else
-	p = (const char *) pstr->raw_mbs + pstr->raw_mbs_idx + byte_idx;
-      mbclen = __mbrtowc (&wc, p, remain_len, &pstr->cur_state);
-      if (BE (mbclen == (size_t) -1 || mbclen == 0
-	      || (mbclen == (size_t) -2 && pstr->bufs_len >= pstr->len), 0))
-	{
-	  /* We treat these cases as a singlebyte character.  */
-	  mbclen = 1;
-	  wc = (wchar_t) pstr->raw_mbs[pstr->raw_mbs_idx + byte_idx];
-	  if (BE (pstr->trans != NULL, 0))
-	    wc = pstr->trans[wc];
-	  pstr->cur_state = prev_st;
-	}
-      else if (BE (mbclen == (size_t) -2, 0))
-	{
-	  /* The buffer doesn't have enough space, finish to build.  */
-	  pstr->cur_state = prev_st;
-	  break;
-	}
-
-      /* Write wide character and padding.  */
-      pstr->wcs[byte_idx++] = wc;
-      /* Write paddings.  */
-      for (remain_len = byte_idx + mbclen - 1; byte_idx < remain_len ;)
-	pstr->wcs[byte_idx++] = WEOF;
-    }
-  pstr->valid_len = byte_idx;
-  pstr->valid_raw_len = byte_idx;
-}
-
-/* Build wide character buffer PSTR->WCS like build_wcs_buffer,
-   but for REG_ICASE.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-build_wcs_upper_buffer (re_string_t *pstr)
-{
-  mbstate_t prev_st;
-  Idx src_idx, byte_idx, end_idx, remain_len;
-  size_t mbclen;
-#ifdef _LIBC
-  char buf[MB_LEN_MAX];
-  assert (MB_LEN_MAX >= pstr->mb_cur_max);
-#else
-  char buf[64];
-#endif
-
-  byte_idx = pstr->valid_len;
-  end_idx = (pstr->bufs_len > pstr->len) ? pstr->len : pstr->bufs_len;
-
-  /* The following optimization assumes that ASCII characters can be
-     mapped to wide characters with a simple cast.  */
-  if (! pstr->map_notascii && pstr->trans == NULL && !pstr->offsets_needed)
-    {
-      while (byte_idx < end_idx)
-	{
-	  wchar_t wc;
-
-	  if (isascii (pstr->raw_mbs[pstr->raw_mbs_idx + byte_idx])
-	      && mbsinit (&pstr->cur_state))
-	    {
-	      /* In case of a singlebyte character.  */
-	      pstr->mbs[byte_idx]
-		= toupper (pstr->raw_mbs[pstr->raw_mbs_idx + byte_idx]);
-	      /* The next step uses the assumption that wchar_t is encoded
-		 ASCII-safe: all ASCII values can be converted like this.  */
-	      pstr->wcs[byte_idx] = (wchar_t) pstr->mbs[byte_idx];
-	      ++byte_idx;
-	      continue;
-	    }
-
-	  remain_len = end_idx - byte_idx;
-	  prev_st = pstr->cur_state;
-	  mbclen = __mbrtowc (&wc,
-			      ((const char *) pstr->raw_mbs + pstr->raw_mbs_idx
-			       + byte_idx), remain_len, &pstr->cur_state);
-	  if (BE (mbclen < (size_t) -2, 1))
-	    {
-	      wchar_t wcu = wc;
-	      if (iswlower (wc))
-		{
-		  size_t mbcdlen;
-
-		  wcu = towupper (wc);
-		  mbcdlen = wcrtomb (buf, wcu, &prev_st);
-		  if (BE (mbclen == mbcdlen, 1))
-		    memcpy (pstr->mbs + byte_idx, buf, mbclen);
-		  else
-		    {
-		      src_idx = byte_idx;
-		      goto offsets_needed;
-		    }
-		}
-	      else
-		memcpy (pstr->mbs + byte_idx,
-			pstr->raw_mbs + pstr->raw_mbs_idx + byte_idx, mbclen);
-	      pstr->wcs[byte_idx++] = wcu;
-	      /* Write paddings.  */
-	      for (remain_len = byte_idx + mbclen - 1; byte_idx < remain_len ;)
-		pstr->wcs[byte_idx++] = WEOF;
-	    }
-	  else if (mbclen == (size_t) -1 || mbclen == 0
-		   || (mbclen == (size_t) -2 && pstr->bufs_len >= pstr->len))
-	    {
-	      /* It is an invalid character, an incomplete character
-		 at the end of the string, or '\0'.  Just use the byte.  */
-	      int ch = pstr->raw_mbs[pstr->raw_mbs_idx + byte_idx];
-	      pstr->mbs[byte_idx] = ch;
-	      /* And also cast it to wide char.  */
-	      pstr->wcs[byte_idx++] = (wchar_t) ch;
-	      if (BE (mbclen == (size_t) -1, 0))
-		pstr->cur_state = prev_st;
-	    }
-	  else
-	    {
-	      /* The buffer doesn't have enough space, finish to build.  */
-	      pstr->cur_state = prev_st;
-	      break;
-	    }
-	}
-      pstr->valid_len = byte_idx;
-      pstr->valid_raw_len = byte_idx;
-      return REG_NOERROR;
-    }
-  else
-    for (src_idx = pstr->valid_raw_len; byte_idx < end_idx;)
-      {
-	wchar_t wc;
-	const char *p;
-      offsets_needed:
-	remain_len = end_idx - byte_idx;
-	prev_st = pstr->cur_state;
-	if (BE (pstr->trans != NULL, 0))
-	  {
-	    int i, ch;
-
-	    for (i = 0; i < pstr->mb_cur_max && i < remain_len; ++i)
-	      {
-		ch = pstr->raw_mbs [pstr->raw_mbs_idx + src_idx + i];
-		buf[i] = pstr->trans[ch];
-	      }
-	    p = (const char *) buf;
-	  }
-	else
-	  p = (const char *) pstr->raw_mbs + pstr->raw_mbs_idx + src_idx;
-	mbclen = __mbrtowc (&wc, p, remain_len, &pstr->cur_state);
-	if (BE (mbclen < (size_t) -2, 1))
-	  {
-	    wchar_t wcu = wc;
-	    if (iswlower (wc))
-	      {
-		size_t mbcdlen;
-
-		wcu = towupper (wc);
-		mbcdlen = wcrtomb ((char *) buf, wcu, &prev_st);
-		if (BE (mbclen == mbcdlen, 1))
-		  memcpy (pstr->mbs + byte_idx, buf, mbclen);
-		else if (mbcdlen != (size_t) -1)
-		  {
-		    size_t i;
-
-		    if (byte_idx + mbcdlen > pstr->bufs_len)
-		      {
-			pstr->cur_state = prev_st;
-			break;
-		      }
-
-		    if (pstr->offsets == NULL)
-		      {
-			pstr->offsets = re_malloc (Idx, pstr->bufs_len);
-
-			if (pstr->offsets == NULL)
-			  return REG_ESPACE;
-		      }
-		    if (!pstr->offsets_needed)
-		      {
-			for (i = 0; i < (size_t) byte_idx; ++i)
-			  pstr->offsets[i] = i;
-			pstr->offsets_needed = 1;
-		      }
-
-		    memcpy (pstr->mbs + byte_idx, buf, mbcdlen);
-		    pstr->wcs[byte_idx] = wcu;
-		    pstr->offsets[byte_idx] = src_idx;
-		    for (i = 1; i < mbcdlen; ++i)
-		      {
-			pstr->offsets[byte_idx + i]
-			  = src_idx + (i < mbclen ? i : mbclen - 1);
-			pstr->wcs[byte_idx + i] = WEOF;
-		      }
-		    pstr->len += mbcdlen - mbclen;
-		    if (pstr->raw_stop > src_idx)
-		      pstr->stop += mbcdlen - mbclen;
-		    end_idx = (pstr->bufs_len > pstr->len)
-			      ? pstr->len : pstr->bufs_len;
-		    byte_idx += mbcdlen;
-		    src_idx += mbclen;
-		    continue;
-		  }
-		else
-		  memcpy (pstr->mbs + byte_idx, p, mbclen);
-	      }
-	    else
-	      memcpy (pstr->mbs + byte_idx, p, mbclen);
-
-	    if (BE (pstr->offsets_needed != 0, 0))
-	      {
-		size_t i;
-		for (i = 0; i < mbclen; ++i)
-		  pstr->offsets[byte_idx + i] = src_idx + i;
-	      }
-	    src_idx += mbclen;
-
-	    pstr->wcs[byte_idx++] = wcu;
-	    /* Write paddings.  */
-	    for (remain_len = byte_idx + mbclen - 1; byte_idx < remain_len ;)
-	      pstr->wcs[byte_idx++] = WEOF;
-	  }
-	else if (mbclen == (size_t) -1 || mbclen == 0
-		 || (mbclen == (size_t) -2 && pstr->bufs_len >= pstr->len))
-	  {
-	    /* It is an invalid character or '\0'.  Just use the byte.  */
-	    int ch = pstr->raw_mbs[pstr->raw_mbs_idx + src_idx];
-
-	    if (BE (pstr->trans != NULL, 0))
-	      ch = pstr->trans [ch];
-	    pstr->mbs[byte_idx] = ch;
-
-	    if (BE (pstr->offsets_needed != 0, 0))
-	      pstr->offsets[byte_idx] = src_idx;
-	    ++src_idx;
-
-	    /* And also cast it to wide char.  */
-	    pstr->wcs[byte_idx++] = (wchar_t) ch;
-	    if (BE (mbclen == (size_t) -1, 0))
-	      pstr->cur_state = prev_st;
-	  }
-	else
-	  {
-	    /* The buffer doesn't have enough space, finish to build.  */
-	    pstr->cur_state = prev_st;
-	    break;
-	  }
-      }
-  pstr->valid_len = byte_idx;
-  pstr->valid_raw_len = src_idx;
-  return REG_NOERROR;
-}
-
-/* Skip characters until the index becomes greater than NEW_RAW_IDX.
-   Return the index.  */
-
-static Idx
-internal_function
-re_string_skip_chars (re_string_t *pstr, Idx new_raw_idx, wint_t *last_wc)
-{
-  mbstate_t prev_st;
-  Idx rawbuf_idx;
-  size_t mbclen;
-  wint_t wc = WEOF;
-
-  /* Skip the characters which are not necessary to check.  */
-  for (rawbuf_idx = pstr->raw_mbs_idx + pstr->valid_raw_len;
-       rawbuf_idx < new_raw_idx;)
-    {
-      wchar_t wc2;
-      Idx remain_len = pstr->raw_len - rawbuf_idx;
-      prev_st = pstr->cur_state;
-      mbclen = __mbrtowc (&wc2, (const char *) pstr->raw_mbs + rawbuf_idx,
-			  remain_len, &pstr->cur_state);
-      if (BE (mbclen == (size_t) -2 || mbclen == (size_t) -1 || mbclen == 0, 0))
-	{
-	  /* We treat these cases as a single byte character.  */
-	  if (mbclen == 0 || remain_len == 0)
-	    wc = L'\0';
-	  else
-	    wc = *(unsigned char *) (pstr->raw_mbs + rawbuf_idx);
-	  mbclen = 1;
-	  pstr->cur_state = prev_st;
-	}
-      else
-	wc = wc2;
-      /* Then proceed the next character.  */
-      rawbuf_idx += mbclen;
-    }
-  *last_wc = wc;
-  return rawbuf_idx;
-}
-#endif /* RE_ENABLE_I18N  */
-
-/* Build the buffer PSTR->MBS, and apply the translation if we need.
-   This function is used in case of REG_ICASE.  */
-
-static void
-internal_function
-build_upper_buffer (re_string_t *pstr)
-{
-  Idx char_idx, end_idx;
-  end_idx = (pstr->bufs_len > pstr->len) ? pstr->len : pstr->bufs_len;
-
-  for (char_idx = pstr->valid_len; char_idx < end_idx; ++char_idx)
-    {
-      int ch = pstr->raw_mbs[pstr->raw_mbs_idx + char_idx];
-      if (BE (pstr->trans != NULL, 0))
-	ch = pstr->trans[ch];
-      if (islower (ch))
-	pstr->mbs[char_idx] = toupper (ch);
-      else
-	pstr->mbs[char_idx] = ch;
-    }
-  pstr->valid_len = char_idx;
-  pstr->valid_raw_len = char_idx;
-}
-
-/* Apply TRANS to the buffer in PSTR.  */
-
-static void
-internal_function
-re_string_translate_buffer (re_string_t *pstr)
-{
-  Idx buf_idx, end_idx;
-  end_idx = (pstr->bufs_len > pstr->len) ? pstr->len : pstr->bufs_len;
-
-  for (buf_idx = pstr->valid_len; buf_idx < end_idx; ++buf_idx)
-    {
-      int ch = pstr->raw_mbs[pstr->raw_mbs_idx + buf_idx];
-      pstr->mbs[buf_idx] = pstr->trans[ch];
-    }
-
-  pstr->valid_len = buf_idx;
-  pstr->valid_raw_len = buf_idx;
-}
-
-/* This function re-construct the buffers.
-   Concretely, convert to wide character in case of pstr->mb_cur_max > 1,
-   convert to upper case in case of REG_ICASE, apply translation.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-re_string_reconstruct (re_string_t *pstr, Idx idx, int eflags)
-{
-  Idx offset;
-
-  if (BE (pstr->raw_mbs_idx <= idx, 0))
-    offset = idx - pstr->raw_mbs_idx;
-  else
-    {
-      /* Reset buffer.  */
-#ifdef RE_ENABLE_I18N
-      if (pstr->mb_cur_max > 1)
-	memset (&pstr->cur_state, '\0', sizeof (mbstate_t));
-#endif /* RE_ENABLE_I18N */
-      pstr->len = pstr->raw_len;
-      pstr->stop = pstr->raw_stop;
-      pstr->valid_len = 0;
-      pstr->raw_mbs_idx = 0;
-      pstr->valid_raw_len = 0;
-      pstr->offsets_needed = 0;
-      pstr->tip_context = ((eflags & REG_NOTBOL) ? CONTEXT_BEGBUF
-			   : CONTEXT_NEWLINE | CONTEXT_BEGBUF);
-      if (!pstr->mbs_allocated)
-	pstr->mbs = (unsigned char *) pstr->raw_mbs;
-      offset = idx;
-    }
-
-  if (BE (offset != 0, 1))
-    {
-      /* Should the already checked characters be kept?  */
-      if (BE (offset < pstr->valid_raw_len, 1))
-	{
-	  /* Yes, move them to the front of the buffer.  */
-#ifdef RE_ENABLE_I18N
-	  if (BE (pstr->offsets_needed, 0))
-	    {
-	      Idx low = 0, high = pstr->valid_len, mid;
-	      do
-		{
-		  mid = (high + low) / 2;
-		  if (pstr->offsets[mid] > offset)
-		    high = mid;
-		  else if (pstr->offsets[mid] < offset)
-		    low = mid + 1;
-		  else
-		    break;
-		}
-	      while (low < high);
-	      if (pstr->offsets[mid] < offset)
-		++mid;
-	      pstr->tip_context = re_string_context_at (pstr, mid - 1,
-							eflags);
-	      /* This can be quite complicated, so handle specially
-		 only the common and easy case where the character with
-		 different length representation of lower and upper
-		 case is present at or after offset.  */
-	      if (pstr->valid_len > offset
-		  && mid == offset && pstr->offsets[mid] == offset)
-		{
-		  memmove (pstr->wcs, pstr->wcs + offset,
-			   (pstr->valid_len - offset) * sizeof (wint_t));
-		  memmove (pstr->mbs, pstr->mbs + offset, pstr->valid_len - offset);
-		  pstr->valid_len -= offset;
-		  pstr->valid_raw_len -= offset;
-		  for (low = 0; low < pstr->valid_len; low++)
-		    pstr->offsets[low] = pstr->offsets[low + offset] - offset;
-		}
-	      else
-		{
-		  /* Otherwise, just find out how long the partial multibyte
-		     character at offset is and fill it with WEOF/255.  */
-		  pstr->len = pstr->raw_len - idx + offset;
-		  pstr->stop = pstr->raw_stop - idx + offset;
-		  pstr->offsets_needed = 0;
-		  while (mid > 0 && pstr->offsets[mid - 1] == offset)
-		    --mid;
-		  while (mid < pstr->valid_len)
-		    if (pstr->wcs[mid] != WEOF)
-		      break;
-		    else
-		      ++mid;
-		  if (mid == pstr->valid_len)
-		    pstr->valid_len = 0;
-		  else
-		    {
-		      pstr->valid_len = pstr->offsets[mid] - offset;
-		      if (pstr->valid_len)
-			{
-			  for (low = 0; low < pstr->valid_len; ++low)
-			    pstr->wcs[low] = WEOF;
-			  memset (pstr->mbs, 255, pstr->valid_len);
-			}
-		    }
-		  pstr->valid_raw_len = pstr->valid_len;
-		}
-	    }
-	  else
-#endif
-	    {
-	      pstr->tip_context = re_string_context_at (pstr, offset - 1,
-							eflags);
-#ifdef RE_ENABLE_I18N
-	      if (pstr->mb_cur_max > 1)
-		memmove (pstr->wcs, pstr->wcs + offset,
-			 (pstr->valid_len - offset) * sizeof (wint_t));
-#endif /* RE_ENABLE_I18N */
-	      if (BE (pstr->mbs_allocated, 0))
-		memmove (pstr->mbs, pstr->mbs + offset,
-			 pstr->valid_len - offset);
-	      pstr->valid_len -= offset;
-	      pstr->valid_raw_len -= offset;
-#if DEBUG
-	      assert (pstr->valid_len > 0);
-#endif
-	    }
-	}
-      else
-	{
-#ifdef RE_ENABLE_I18N
-	  /* No, skip all characters until IDX.  */
-	  Idx prev_valid_len = pstr->valid_len;
-
-	  if (BE (pstr->offsets_needed, 0))
-	    {
-	      pstr->len = pstr->raw_len - idx + offset;
-	      pstr->stop = pstr->raw_stop - idx + offset;
-	      pstr->offsets_needed = 0;
-	    }
-#endif
-	  pstr->valid_len = 0;
-#ifdef RE_ENABLE_I18N
-	  if (pstr->mb_cur_max > 1)
-	    {
-	      Idx wcs_idx;
-	      wint_t wc = WEOF;
-
-	      if (pstr->is_utf8)
-		{
-		  const unsigned char *raw, *p, *end;
-
-		  /* Special case UTF-8.  Multi-byte chars start with any
-		     byte other than 0x80 - 0xbf.  */
-		  raw = pstr->raw_mbs + pstr->raw_mbs_idx;
-		  end = raw + (offset - pstr->mb_cur_max);
-		  if (end < pstr->raw_mbs)
-		    end = pstr->raw_mbs;
-		  p = raw + offset - 1;
-#ifdef _LIBC
-		  /* We know the wchar_t encoding is UCS4, so for the simple
-		     case, ASCII characters, skip the conversion step.  */
-		  if (isascii (*p) && BE (pstr->trans == NULL, 1))
-		    {
-		      memset (&pstr->cur_state, '\0', sizeof (mbstate_t));
-		      /* pstr->valid_len = 0; */
-		      wc = (wchar_t) *p;
-		    }
-		  else
-#endif
-		    for (; p >= end; --p)
-		      if ((*p & 0xc0) != 0x80)
-			{
-			  mbstate_t cur_state;
-			  wchar_t wc2;
-			  Idx mlen = raw + pstr->len - p;
-			  unsigned char buf[6];
-			  size_t mbclen;
-
-			  const unsigned char *pp = p;
-			  if (BE (pstr->trans != NULL, 0))
-			    {
-			      int i = mlen < 6 ? mlen : 6;
-			      while (--i >= 0)
-				buf[i] = pstr->trans[p[i]];
-			      pp = buf;
-			    }
-			  /* XXX Don't use mbrtowc, we know which conversion
-			     to use (UTF-8 -> UCS4).  */
-			  memset (&cur_state, 0, sizeof (cur_state));
-			  mbclen = __mbrtowc (&wc2, (const char *) pp, mlen,
-					      &cur_state);
-			  if (raw + offset - p <= mbclen
-			      && mbclen < (size_t) -2)
-			    {
-			      memset (&pstr->cur_state, '\0',
-				      sizeof (mbstate_t));
-			      pstr->valid_len = mbclen - (raw + offset - p);
-			      wc = wc2;
-			    }
-			  break;
-			}
-		}
-
-	      if (wc == WEOF)
-		pstr->valid_len = re_string_skip_chars (pstr, idx, &wc) - idx;
-	      if (wc == WEOF)
-		pstr->tip_context
-		  = re_string_context_at (pstr, prev_valid_len - 1, eflags);
-	      else
-		pstr->tip_context = ((BE (pstr->word_ops_used != 0, 0)
-				      && IS_WIDE_WORD_CHAR (wc))
-				     ? CONTEXT_WORD
-				     : ((IS_WIDE_NEWLINE (wc)
-					 && pstr->newline_anchor)
-					? CONTEXT_NEWLINE : 0));
-	      if (BE (pstr->valid_len, 0))
-		{
-		  for (wcs_idx = 0; wcs_idx < pstr->valid_len; ++wcs_idx)
-		    pstr->wcs[wcs_idx] = WEOF;
-		  if (pstr->mbs_allocated)
-		    memset (pstr->mbs, 255, pstr->valid_len);
-		}
-	      pstr->valid_raw_len = pstr->valid_len;
-	    }
-	  else
-#endif /* RE_ENABLE_I18N */
-	    {
-	      int c = pstr->raw_mbs[pstr->raw_mbs_idx + offset - 1];
-	      pstr->valid_raw_len = 0;
-	      if (pstr->trans)
-		c = pstr->trans[c];
-	      pstr->tip_context = (bitset_contain (pstr->word_char, c)
-				   ? CONTEXT_WORD
-				   : ((IS_NEWLINE (c) && pstr->newline_anchor)
-				      ? CONTEXT_NEWLINE : 0));
-	    }
-	}
-      if (!BE (pstr->mbs_allocated, 0))
-	pstr->mbs += offset;
-    }
-  pstr->raw_mbs_idx = idx;
-  pstr->len -= offset;
-  pstr->stop -= offset;
-
-  /* Then build the buffers.  */
-#ifdef RE_ENABLE_I18N
-  if (pstr->mb_cur_max > 1)
-    {
-      if (pstr->icase)
-	{
-	  reg_errcode_t ret = build_wcs_upper_buffer (pstr);
-	  if (BE (ret != REG_NOERROR, 0))
-	    return ret;
-	}
-      else
-	build_wcs_buffer (pstr);
-    }
-  else
-#endif /* RE_ENABLE_I18N */
-    if (BE (pstr->mbs_allocated, 0))
-      {
-	if (pstr->icase)
-	  build_upper_buffer (pstr);
-	else if (pstr->trans != NULL)
-	  re_string_translate_buffer (pstr);
-      }
-    else
-      pstr->valid_len = pstr->len;
-
-  pstr->cur_idx = 0;
-  return REG_NOERROR;
-}
-
-static unsigned char
-internal_function __attribute__ ((pure))
-re_string_peek_byte_case (const re_string_t *pstr, Idx idx)
-{
-  int ch;
-  Idx off;
-
-  /* Handle the common (easiest) cases first.  */
-  if (BE (!pstr->mbs_allocated, 1))
-    return re_string_peek_byte (pstr, idx);
-
-#ifdef RE_ENABLE_I18N
-  if (pstr->mb_cur_max > 1
-      && ! re_string_is_single_byte_char (pstr, pstr->cur_idx + idx))
-    return re_string_peek_byte (pstr, idx);
-#endif
-
-  off = pstr->cur_idx + idx;
-#ifdef RE_ENABLE_I18N
-  if (pstr->offsets_needed)
-    off = pstr->offsets[off];
-#endif
-
-  ch = pstr->raw_mbs[pstr->raw_mbs_idx + off];
-
-#ifdef RE_ENABLE_I18N
-  /* Ensure that e.g. for tr_TR.UTF-8 BACKSLASH DOTLESS SMALL LETTER I
-     this function returns CAPITAL LETTER I instead of first byte of
-     DOTLESS SMALL LETTER I.  The latter would confuse the parser,
-     since peek_byte_case doesn't advance cur_idx in any way.  */
-  if (pstr->offsets_needed && !isascii (ch))
-    return re_string_peek_byte (pstr, idx);
-#endif
-
-  return ch;
-}
-
-static unsigned char
-internal_function
-re_string_fetch_byte_case (re_string_t *pstr)
-{
-  if (BE (!pstr->mbs_allocated, 1))
-    return re_string_fetch_byte (pstr);
-
-#ifdef RE_ENABLE_I18N
-  if (pstr->offsets_needed)
-    {
-      Idx off;
-      int ch;
-
-      /* For tr_TR.UTF-8 [[:islower:]] there is
-	 [[: CAPITAL LETTER I WITH DOT lower:]] in mbs.  Skip
-	 in that case the whole multi-byte character and return
-	 the original letter.  On the other side, with
-	 [[: DOTLESS SMALL LETTER I return [[:I, as doing
-	 anything else would complicate things too much.  */
-
-      if (!re_string_first_byte (pstr, pstr->cur_idx))
-	return re_string_fetch_byte (pstr);
-
-      off = pstr->offsets[pstr->cur_idx];
-      ch = pstr->raw_mbs[pstr->raw_mbs_idx + off];
-
-      if (! isascii (ch))
-	return re_string_fetch_byte (pstr);
-
-      re_string_skip_bytes (pstr,
-			    re_string_char_size_at (pstr, pstr->cur_idx));
-      return ch;
-    }
-#endif
-
-  return pstr->raw_mbs[pstr->raw_mbs_idx + pstr->cur_idx++];
-}
-
-static void
-internal_function
-re_string_destruct (re_string_t *pstr)
-{
-#ifdef RE_ENABLE_I18N
-  re_free (pstr->wcs);
-  re_free (pstr->offsets);
-#endif /* RE_ENABLE_I18N  */
-  if (pstr->mbs_allocated)
-    re_free (pstr->mbs);
-}
-
-/* Return the context at IDX in INPUT.  */
-
-static unsigned int
-internal_function
-re_string_context_at (const re_string_t *input, Idx idx, int eflags)
-{
-  int c;
-  if (BE (! REG_VALID_INDEX (idx), 0))
-    /* In this case, we use the value stored in input->tip_context,
-       since we can't know the character in input->mbs[-1] here.  */
-    return input->tip_context;
-  if (BE (idx == input->len, 0))
-    return ((eflags & REG_NOTEOL) ? CONTEXT_ENDBUF
-	    : CONTEXT_NEWLINE | CONTEXT_ENDBUF);
-#ifdef RE_ENABLE_I18N
-  if (input->mb_cur_max > 1)
-    {
-      wint_t wc;
-      Idx wc_idx = idx;
-      while(input->wcs[wc_idx] == WEOF)
-	{
-#ifdef DEBUG
-	  /* It must not happen.  */
-	  assert (REG_VALID_INDEX (wc_idx));
-#endif
-	  --wc_idx;
-	  if (! REG_VALID_INDEX (wc_idx))
-	    return input->tip_context;
-	}
-      wc = input->wcs[wc_idx];
-      if (BE (input->word_ops_used != 0, 0) && IS_WIDE_WORD_CHAR (wc))
-	return CONTEXT_WORD;
-      return (IS_WIDE_NEWLINE (wc) && input->newline_anchor
-	      ? CONTEXT_NEWLINE : 0);
-    }
-  else
-#endif
-    {
-      c = re_string_byte_at (input, idx);
-      if (bitset_contain (input->word_char, c))
-	return CONTEXT_WORD;
-      return IS_NEWLINE (c) && input->newline_anchor ? CONTEXT_NEWLINE : 0;
-    }
-}
-
-/* Functions for set operation.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-re_node_set_alloc (re_node_set *set, Idx size)
-{
-  set->alloc = size;
-  set->nelem = 0;
-  set->elems = re_malloc (Idx, size);
-  if (BE (set->elems == NULL, 0) && (MALLOC_0_IS_NONNULL || size != 0))
-    return REG_ESPACE;
-  return REG_NOERROR;
-}
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-re_node_set_init_1 (re_node_set *set, Idx elem)
-{
-  set->alloc = 1;
-  set->nelem = 1;
-  set->elems = re_malloc (Idx, 1);
-  if (BE (set->elems == NULL, 0))
-    {
-      set->alloc = set->nelem = 0;
-      return REG_ESPACE;
-    }
-  set->elems[0] = elem;
-  return REG_NOERROR;
-}
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-re_node_set_init_2 (re_node_set *set, Idx elem1, Idx elem2)
-{
-  set->alloc = 2;
-  set->elems = re_malloc (Idx, 2);
-  if (BE (set->elems == NULL, 0))
-    return REG_ESPACE;
-  if (elem1 == elem2)
-    {
-      set->nelem = 1;
-      set->elems[0] = elem1;
-    }
-  else
-    {
-      set->nelem = 2;
-      if (elem1 < elem2)
-	{
-	  set->elems[0] = elem1;
-	  set->elems[1] = elem2;
-	}
-      else
-	{
-	  set->elems[0] = elem2;
-	  set->elems[1] = elem1;
-	}
-    }
-  return REG_NOERROR;
-}
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-re_node_set_init_copy (re_node_set *dest, const re_node_set *src)
-{
-  dest->nelem = src->nelem;
-  if (src->nelem > 0)
-    {
-      dest->alloc = dest->nelem;
-      dest->elems = re_malloc (Idx, dest->alloc);
-      if (BE (dest->elems == NULL, 0))
-	{
-	  dest->alloc = dest->nelem = 0;
-	  return REG_ESPACE;
-	}
-      memcpy (dest->elems, src->elems, src->nelem * sizeof (Idx));
-    }
-  else
-    re_node_set_init_empty (dest);
-  return REG_NOERROR;
-}
-
-/* Calculate the intersection of the sets SRC1 and SRC2. And merge it to
-   DEST. Return value indicate the error code or REG_NOERROR if succeeded.
-   Note: We assume dest->elems is NULL, when dest->alloc is 0.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-re_node_set_add_intersect (re_node_set *dest, const re_node_set *src1,
-			   const re_node_set *src2)
-{
-  Idx i1, i2, is, id, delta, sbase;
-  if (src1->nelem == 0 || src2->nelem == 0)
-    return REG_NOERROR;
-
-  /* We need dest->nelem + 2 * elems_in_intersection; this is a
-     conservative estimate.  */
-  if (src1->nelem + src2->nelem + dest->nelem > dest->alloc)
-    {
-      Idx new_alloc = src1->nelem + src2->nelem + dest->alloc;
-      Idx *new_elems = re_realloc (dest->elems, Idx, new_alloc);
-      if (BE (new_elems == NULL, 0))
-	return REG_ESPACE;
-      dest->elems = new_elems;
-      dest->alloc = new_alloc;
-    }
-
-  /* Find the items in the intersection of SRC1 and SRC2, and copy
-     into the top of DEST those that are not already in DEST itself.  */
-  sbase = dest->nelem + src1->nelem + src2->nelem;
-  i1 = src1->nelem - 1;
-  i2 = src2->nelem - 1;
-  id = dest->nelem - 1;
-  for (;;)
-    {
-      if (src1->elems[i1] == src2->elems[i2])
-	{
-	  /* Try to find the item in DEST.  Maybe we could binary search?  */
-	  while (REG_VALID_INDEX (id) && dest->elems[id] > src1->elems[i1])
-	    --id;
-
-          if (! REG_VALID_INDEX (id) || dest->elems[id] != src1->elems[i1])
-            dest->elems[--sbase] = src1->elems[i1];
-
-	  if (! REG_VALID_INDEX (--i1) || ! REG_VALID_INDEX (--i2))
-	    break;
-	}
-
-      /* Lower the highest of the two items.  */
-      else if (src1->elems[i1] < src2->elems[i2])
-	{
-	  if (! REG_VALID_INDEX (--i2))
-	    break;
-	}
-      else
-	{
-	  if (! REG_VALID_INDEX (--i1))
-	    break;
-	}
-    }
-
-  id = dest->nelem - 1;
-  is = dest->nelem + src1->nelem + src2->nelem - 1;
-  delta = is - sbase + 1;
-
-  /* Now copy.  When DELTA becomes zero, the remaining
-     DEST elements are already in place; this is more or
-     less the same loop that is in re_node_set_merge.  */
-  dest->nelem += delta;
-  if (delta > 0 && REG_VALID_INDEX (id))
-    for (;;)
-      {
-	if (dest->elems[is] > dest->elems[id])
-	  {
-	    /* Copy from the top.  */
-	    dest->elems[id + delta--] = dest->elems[is--];
-	    if (delta == 0)
-	      break;
-	  }
-	else
-	  {
-	    /* Slide from the bottom.  */
-	    dest->elems[id + delta] = dest->elems[id];
-	    if (! REG_VALID_INDEX (--id))
-	      break;
-	  }
-      }
-
-  /* Copy remaining SRC elements.  */
-  memcpy (dest->elems, dest->elems + sbase, delta * sizeof (Idx));
-
-  return REG_NOERROR;
-}
-
-/* Calculate the union set of the sets SRC1 and SRC2. And store it to
-   DEST. Return value indicate the error code or REG_NOERROR if succeeded.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-re_node_set_init_union (re_node_set *dest, const re_node_set *src1,
-			const re_node_set *src2)
-{
-  Idx i1, i2, id;
-  if (src1 != NULL && src1->nelem > 0 && src2 != NULL && src2->nelem > 0)
-    {
-      dest->alloc = src1->nelem + src2->nelem;
-      dest->elems = re_malloc (Idx, dest->alloc);
-      if (BE (dest->elems == NULL, 0))
-	return REG_ESPACE;
-    }
-  else
-    {
-      if (src1 != NULL && src1->nelem > 0)
-	return re_node_set_init_copy (dest, src1);
-      else if (src2 != NULL && src2->nelem > 0)
-	return re_node_set_init_copy (dest, src2);
-      else
-	re_node_set_init_empty (dest);
-      return REG_NOERROR;
-    }
-  for (i1 = i2 = id = 0 ; i1 < src1->nelem && i2 < src2->nelem ;)
-    {
-      if (src1->elems[i1] > src2->elems[i2])
-	{
-	  dest->elems[id++] = src2->elems[i2++];
-	  continue;
-	}
-      if (src1->elems[i1] == src2->elems[i2])
-	++i2;
-      dest->elems[id++] = src1->elems[i1++];
-    }
-  if (i1 < src1->nelem)
-    {
-      memcpy (dest->elems + id, src1->elems + i1,
-	     (src1->nelem - i1) * sizeof (Idx));
-      id += src1->nelem - i1;
-    }
-  else if (i2 < src2->nelem)
-    {
-      memcpy (dest->elems + id, src2->elems + i2,
-	     (src2->nelem - i2) * sizeof (Idx));
-      id += src2->nelem - i2;
-    }
-  dest->nelem = id;
-  return REG_NOERROR;
-}
-
-/* Calculate the union set of the sets DEST and SRC. And store it to
-   DEST. Return value indicate the error code or REG_NOERROR if succeeded.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-re_node_set_merge (re_node_set *dest, const re_node_set *src)
-{
-  Idx is, id, sbase, delta;
-  if (src == NULL || src->nelem == 0)
-    return REG_NOERROR;
-  if (dest->alloc < 2 * src->nelem + dest->nelem)
-    {
-      Idx new_alloc = 2 * (src->nelem + dest->alloc);
-      Idx *new_buffer = re_realloc (dest->elems, Idx, new_alloc);
-      if (BE (new_buffer == NULL, 0))
-	return REG_ESPACE;
-      dest->elems = new_buffer;
-      dest->alloc = new_alloc;
-    }
-
-  if (BE (dest->nelem == 0, 0))
-    {
-      dest->nelem = src->nelem;
-      memcpy (dest->elems, src->elems, src->nelem * sizeof (Idx));
-      return REG_NOERROR;
-    }
-
-  /* Copy into the top of DEST the items of SRC that are not
-     found in DEST.  Maybe we could binary search in DEST?  */
-  for (sbase = dest->nelem + 2 * src->nelem,
-       is = src->nelem - 1, id = dest->nelem - 1;
-       REG_VALID_INDEX (is) && REG_VALID_INDEX (id); )
-    {
-      if (dest->elems[id] == src->elems[is])
-	is--, id--;
-      else if (dest->elems[id] < src->elems[is])
-	dest->elems[--sbase] = src->elems[is--];
-      else /* if (dest->elems[id] > src->elems[is]) */
-	--id;
-    }
-
-  if (REG_VALID_INDEX (is))
-    {
-      /* If DEST is exhausted, the remaining items of SRC must be unique.  */
-      sbase -= is + 1;
-      memcpy (dest->elems + sbase, src->elems, (is + 1) * sizeof (Idx));
-    }
-
-  id = dest->nelem - 1;
-  is = dest->nelem + 2 * src->nelem - 1;
-  delta = is - sbase + 1;
-  if (delta == 0)
-    return REG_NOERROR;
-
-  /* Now copy.  When DELTA becomes zero, the remaining
-     DEST elements are already in place.  */
-  dest->nelem += delta;
-  for (;;)
-    {
-      if (dest->elems[is] > dest->elems[id])
-	{
-	  /* Copy from the top.  */
-	  dest->elems[id + delta--] = dest->elems[is--];
-	  if (delta == 0)
-	    break;
-	}
-      else
-	{
-	  /* Slide from the bottom.  */
-	  dest->elems[id + delta] = dest->elems[id];
-	  if (! REG_VALID_INDEX (--id))
-	    {
-	      /* Copy remaining SRC elements.  */
-	      memcpy (dest->elems, dest->elems + sbase,
-		      delta * sizeof (Idx));
-	      break;
-	    }
-	}
-    }
-
-  return REG_NOERROR;
-}
-
-/* Insert the new element ELEM to the re_node_set* SET.
-   SET should not already have ELEM.
-   Return true if successful.  */
-
-static bool
-internal_function __attribute_warn_unused_result__
-re_node_set_insert (re_node_set *set, Idx elem)
-{
-  Idx idx;
-  /* In case the set is empty.  */
-  if (set->alloc == 0)
-    return BE (re_node_set_init_1 (set, elem) == REG_NOERROR, 1);
-
-  if (BE (set->nelem, 0) == 0)
-    {
-      /* We already guaranteed above that set->alloc != 0.  */
-      set->elems[0] = elem;
-      ++set->nelem;
-      return true;
-    }
-
-  /* Realloc if we need.  */
-  if (set->alloc == set->nelem)
-    {
-      Idx *new_elems;
-      set->alloc = set->alloc * 2;
-      new_elems = re_realloc (set->elems, Idx, set->alloc);
-      if (BE (new_elems == NULL, 0))
-	return false;
-      set->elems = new_elems;
-    }
-
-  /* Move the elements which follows the new element.  Test the
-     first element separately to skip a check in the inner loop.  */
-  if (elem < set->elems[0])
-    {
-      idx = 0;
-      for (idx = set->nelem; idx > 0; idx--)
-	set->elems[idx] = set->elems[idx - 1];
-    }
-  else
-    {
-      for (idx = set->nelem; set->elems[idx - 1] > elem; idx--)
-	set->elems[idx] = set->elems[idx - 1];
-    }
-
-  /* Insert the new element.  */
-  set->elems[idx] = elem;
-  ++set->nelem;
-  return true;
-}
-
-/* Insert the new element ELEM to the re_node_set* SET.
-   SET should not already have any element greater than or equal to ELEM.
-   Return true if successful.  */
-
-static bool
-internal_function __attribute_warn_unused_result__
-re_node_set_insert_last (re_node_set *set, Idx elem)
-{
-  /* Realloc if we need.  */
-  if (set->alloc == set->nelem)
-    {
-      Idx *new_elems;
-      set->alloc = (set->alloc + 1) * 2;
-      new_elems = re_realloc (set->elems, Idx, set->alloc);
-      if (BE (new_elems == NULL, 0))
-	return false;
-      set->elems = new_elems;
-    }
-
-  /* Insert the new element.  */
-  set->elems[set->nelem++] = elem;
-  return true;
-}
-
-/* Compare two node sets SET1 and SET2.
-   Return true if SET1 and SET2 are equivalent.  */
-
-static bool
-internal_function __attribute__ ((pure))
-re_node_set_compare (const re_node_set *set1, const re_node_set *set2)
-{
-  Idx i;
-  if (set1 == NULL || set2 == NULL || set1->nelem != set2->nelem)
-    return false;
-  for (i = set1->nelem ; REG_VALID_INDEX (--i) ; )
-    if (set1->elems[i] != set2->elems[i])
-      return false;
-  return true;
-}
-
-/* Return (idx + 1) if SET contains the element ELEM, return 0 otherwise.  */
-
-static Idx
-internal_function __attribute__ ((pure))
-re_node_set_contains (const re_node_set *set, Idx elem)
-{
-  __re_size_t idx, right, mid;
-  if (! REG_VALID_NONZERO_INDEX (set->nelem))
-    return 0;
-
-  /* Binary search the element.  */
-  idx = 0;
-  right = set->nelem - 1;
-  while (idx < right)
-    {
-      mid = (idx + right) / 2;
-      if (set->elems[mid] < elem)
-	idx = mid + 1;
-      else
-	right = mid;
-    }
-  return set->elems[idx] == elem ? idx + 1 : 0;
-}
-
-static void
-internal_function
-re_node_set_remove_at (re_node_set *set, Idx idx)
-{
-  if (idx < 0 || idx >= set->nelem)
-    return;
-  --set->nelem;
-  for (; idx < set->nelem; idx++)
-    set->elems[idx] = set->elems[idx + 1];
-}
-
-
-/* Add the token TOKEN to dfa->nodes, and return the index of the token.
-   Or return REG_MISSING if an error occurred.  */
-
-static Idx
-internal_function
-re_dfa_add_node (re_dfa_t *dfa, re_token_t token)
-{
-  if (BE (dfa->nodes_len >= dfa->nodes_alloc, 0))
-    {
-      size_t new_nodes_alloc = dfa->nodes_alloc * 2;
-      Idx *new_nexts, *new_indices;
-      re_node_set *new_edests, *new_eclosures;
-      re_token_t *new_nodes;
-
-      /* Avoid overflows in realloc.  */
-      const size_t max_object_size = MAX (sizeof (re_token_t),
-					  MAX (sizeof (re_node_set),
-					       sizeof (Idx)));
-      if (BE (MIN (IDX_MAX, SIZE_MAX / max_object_size) < new_nodes_alloc, 0))
-	return REG_MISSING;
-
-      new_nodes = re_realloc (dfa->nodes, re_token_t, new_nodes_alloc);
-      if (BE (new_nodes == NULL, 0))
-	return REG_MISSING;
-      dfa->nodes = new_nodes;
-      new_nexts = re_realloc (dfa->nexts, Idx, new_nodes_alloc);
-      new_indices = re_realloc (dfa->org_indices, Idx, new_nodes_alloc);
-      new_edests = re_realloc (dfa->edests, re_node_set, new_nodes_alloc);
-      new_eclosures = re_realloc (dfa->eclosures, re_node_set, new_nodes_alloc);
-      if (BE (new_nexts == NULL || new_indices == NULL
-	      || new_edests == NULL || new_eclosures == NULL, 0))
-	return REG_MISSING;
-      dfa->nexts = new_nexts;
-      dfa->org_indices = new_indices;
-      dfa->edests = new_edests;
-      dfa->eclosures = new_eclosures;
-      dfa->nodes_alloc = new_nodes_alloc;
-    }
-  dfa->nodes[dfa->nodes_len] = token;
-  dfa->nodes[dfa->nodes_len].constraint = 0;
-#ifdef RE_ENABLE_I18N
-  dfa->nodes[dfa->nodes_len].accept_mb =
-    ((token.type == OP_PERIOD && dfa->mb_cur_max > 1)
-     || token.type == COMPLEX_BRACKET);
-#endif
-  dfa->nexts[dfa->nodes_len] = REG_MISSING;
-  re_node_set_init_empty (dfa->edests + dfa->nodes_len);
-  re_node_set_init_empty (dfa->eclosures + dfa->nodes_len);
-  return dfa->nodes_len++;
-}
-
-static re_hashval_t
-internal_function
-calc_state_hash (const re_node_set *nodes, unsigned int context)
-{
-  re_hashval_t hash = nodes->nelem + context;
-  Idx i;
-  for (i = 0 ; i < nodes->nelem ; i++)
-    hash += nodes->elems[i];
-  return hash;
-}
-
-/* Search for the state whose node_set is equivalent to NODES.
-   Return the pointer to the state, if we found it in the DFA.
-   Otherwise create the new one and return it.  In case of an error
-   return NULL and set the error code in ERR.
-   Note: - We assume NULL as the invalid state, then it is possible that
-	   return value is NULL and ERR is REG_NOERROR.
-	 - We never return non-NULL value in case of any errors, it is for
-	   optimization.  */
-
-static re_dfastate_t *
-internal_function __attribute_warn_unused_result__
-re_acquire_state (reg_errcode_t *err, const re_dfa_t *dfa,
-		  const re_node_set *nodes)
-{
-  re_hashval_t hash;
-  re_dfastate_t *new_state;
-  struct re_state_table_entry *spot;
-  Idx i;
-#ifdef lint
-  /* Suppress bogus uninitialized-variable warnings.  */
-  *err = REG_NOERROR;
-#endif
-  if (BE (nodes->nelem == 0, 0))
-    {
-      *err = REG_NOERROR;
-      return NULL;
-    }
-  hash = calc_state_hash (nodes, 0);
-  spot = dfa->state_table + (hash & dfa->state_hash_mask);
-
-  for (i = 0 ; i < spot->num ; i++)
-    {
-      re_dfastate_t *state = spot->array[i];
-      if (hash != state->hash)
-	continue;
-      if (re_node_set_compare (&state->nodes, nodes))
-	return state;
-    }
-
-  /* There are no appropriate state in the dfa, create the new one.  */
-  new_state = create_ci_newstate (dfa, nodes, hash);
-  if (BE (new_state == NULL, 0))
-    *err = REG_ESPACE;
-
-  return new_state;
-}
-
-/* Search for the state whose node_set is equivalent to NODES and
-   whose context is equivalent to CONTEXT.
-   Return the pointer to the state, if we found it in the DFA.
-   Otherwise create the new one and return it.  In case of an error
-   return NULL and set the error code in ERR.
-   Note: - We assume NULL as the invalid state, then it is possible that
-	   return value is NULL and ERR is REG_NOERROR.
-	 - We never return non-NULL value in case of any errors, it is for
-	   optimization.  */
-
-static re_dfastate_t *
-internal_function __attribute_warn_unused_result__
-re_acquire_state_context (reg_errcode_t *err, const re_dfa_t *dfa,
-			  const re_node_set *nodes, unsigned int context)
-{
-  re_hashval_t hash;
-  re_dfastate_t *new_state;
-  struct re_state_table_entry *spot;
-  Idx i;
-#ifdef lint
-  /* Suppress bogus uninitialized-variable warnings.  */
-  *err = REG_NOERROR;
-#endif
-  if (nodes->nelem == 0)
-    {
-      *err = REG_NOERROR;
-      return NULL;
-    }
-  hash = calc_state_hash (nodes, context);
-  spot = dfa->state_table + (hash & dfa->state_hash_mask);
-
-  for (i = 0 ; i < spot->num ; i++)
-    {
-      re_dfastate_t *state = spot->array[i];
-      if (state->hash == hash
-	  && state->context == context
-	  && re_node_set_compare (state->entrance_nodes, nodes))
-	return state;
-    }
-  /* There are no appropriate state in 'dfa', create the new one.  */
-  new_state = create_cd_newstate (dfa, nodes, context, hash);
-  if (BE (new_state == NULL, 0))
-    *err = REG_ESPACE;
-
-  return new_state;
-}
-
-/* Finish initialization of the new state NEWSTATE, and using its hash value
-   HASH put in the appropriate bucket of DFA's state table.  Return value
-   indicates the error code if failed.  */
-
-static reg_errcode_t
-__attribute_warn_unused_result__
-register_state (const re_dfa_t *dfa, re_dfastate_t *newstate,
-		re_hashval_t hash)
-{
-  struct re_state_table_entry *spot;
-  reg_errcode_t err;
-  Idx i;
-
-  newstate->hash = hash;
-  err = re_node_set_alloc (&newstate->non_eps_nodes, newstate->nodes.nelem);
-  if (BE (err != REG_NOERROR, 0))
-    return REG_ESPACE;
-  for (i = 0; i < newstate->nodes.nelem; i++)
-    {
-      Idx elem = newstate->nodes.elems[i];
-      if (!IS_EPSILON_NODE (dfa->nodes[elem].type))
-	if (! re_node_set_insert_last (&newstate->non_eps_nodes, elem))
-	  return REG_ESPACE;
-    }
-
-  spot = dfa->state_table + (hash & dfa->state_hash_mask);
-  if (BE (spot->alloc <= spot->num, 0))
-    {
-      Idx new_alloc = 2 * spot->num + 2;
-      re_dfastate_t **new_array = re_realloc (spot->array, re_dfastate_t *,
-					      new_alloc);
-      if (BE (new_array == NULL, 0))
-	return REG_ESPACE;
-      spot->array = new_array;
-      spot->alloc = new_alloc;
-    }
-  spot->array[spot->num++] = newstate;
-  return REG_NOERROR;
-}
-
-static void
-free_state (re_dfastate_t *state)
-{
-  re_node_set_free (&state->non_eps_nodes);
-  re_node_set_free (&state->inveclosure);
-  if (state->entrance_nodes != &state->nodes)
-    {
-      re_node_set_free (state->entrance_nodes);
-      re_free (state->entrance_nodes);
-    }
-  re_node_set_free (&state->nodes);
-  re_free (state->word_trtable);
-  re_free (state->trtable);
-  re_free (state);
-}
-
-/* Create the new state which is independent of contexts.
-   Return the new state if succeeded, otherwise return NULL.  */
-
-static re_dfastate_t *
-internal_function __attribute_warn_unused_result__
-create_ci_newstate (const re_dfa_t *dfa, const re_node_set *nodes,
-		    re_hashval_t hash)
-{
-  Idx i;
-  reg_errcode_t err;
-  re_dfastate_t *newstate;
-
-  newstate = (re_dfastate_t *) calloc (sizeof (re_dfastate_t), 1);
-  if (BE (newstate == NULL, 0))
-    return NULL;
-  err = re_node_set_init_copy (&newstate->nodes, nodes);
-  if (BE (err != REG_NOERROR, 0))
-    {
-      re_free (newstate);
-      return NULL;
-    }
-
-  newstate->entrance_nodes = &newstate->nodes;
-  for (i = 0 ; i < nodes->nelem ; i++)
-    {
-      re_token_t *node = dfa->nodes + nodes->elems[i];
-      re_token_type_t type = node->type;
-      if (type == CHARACTER && !node->constraint)
-	continue;
-#ifdef RE_ENABLE_I18N
-      newstate->accept_mb |= node->accept_mb;
-#endif /* RE_ENABLE_I18N */
-
-      /* If the state has the halt node, the state is a halt state.  */
-      if (type == END_OF_RE)
-	newstate->halt = 1;
-      else if (type == OP_BACK_REF)
-	newstate->has_backref = 1;
-      else if (type == ANCHOR || node->constraint)
-	newstate->has_constraint = 1;
-    }
-  err = register_state (dfa, newstate, hash);
-  if (BE (err != REG_NOERROR, 0))
-    {
-      free_state (newstate);
-      newstate = NULL;
-    }
-  return newstate;
-}
-
-/* Create the new state which is depend on the context CONTEXT.
-   Return the new state if succeeded, otherwise return NULL.  */
-
-static re_dfastate_t *
-internal_function __attribute_warn_unused_result__
-create_cd_newstate (const re_dfa_t *dfa, const re_node_set *nodes,
-		    unsigned int context, re_hashval_t hash)
-{
-  Idx i, nctx_nodes = 0;
-  reg_errcode_t err;
-  re_dfastate_t *newstate;
-
-  newstate = (re_dfastate_t *) calloc (sizeof (re_dfastate_t), 1);
-  if (BE (newstate == NULL, 0))
-    return NULL;
-  err = re_node_set_init_copy (&newstate->nodes, nodes);
-  if (BE (err != REG_NOERROR, 0))
-    {
-      re_free (newstate);
-      return NULL;
-    }
-
-  newstate->context = context;
-  newstate->entrance_nodes = &newstate->nodes;
-
-  for (i = 0 ; i < nodes->nelem ; i++)
-    {
-      re_token_t *node = dfa->nodes + nodes->elems[i];
-      re_token_type_t type = node->type;
-      unsigned int constraint = node->constraint;
-
-      if (type == CHARACTER && !constraint)
-	continue;
-#ifdef RE_ENABLE_I18N
-      newstate->accept_mb |= node->accept_mb;
-#endif /* RE_ENABLE_I18N */
-
-      /* If the state has the halt node, the state is a halt state.  */
-      if (type == END_OF_RE)
-	newstate->halt = 1;
-      else if (type == OP_BACK_REF)
-	newstate->has_backref = 1;
-
-      if (constraint)
-	{
-	  if (newstate->entrance_nodes == &newstate->nodes)
-	    {
-	      newstate->entrance_nodes = re_malloc (re_node_set, 1);
-	      if (BE (newstate->entrance_nodes == NULL, 0))
-		{
-		  free_state (newstate);
-		  return NULL;
-		}
-	      if (re_node_set_init_copy (newstate->entrance_nodes, nodes)
-		  != REG_NOERROR)
-		return NULL;
-	      nctx_nodes = 0;
-	      newstate->has_constraint = 1;
-	    }
-
-	  if (NOT_SATISFY_PREV_CONSTRAINT (constraint,context))
-	    {
-	      re_node_set_remove_at (&newstate->nodes, i - nctx_nodes);
-	      ++nctx_nodes;
-	    }
-	}
-    }
-  err = register_state (dfa, newstate, hash);
-  if (BE (err != REG_NOERROR, 0))
-    {
-      free_state (newstate);
-      newstate = NULL;
-    }
-  return  newstate;
-}
diff --git a/contrib/tools/bison/lib/regex_internal.h b/contrib/tools/bison/lib/regex_internal.h
deleted file mode 100644
index 6205dbe726..0000000000
--- a/contrib/tools/bison/lib/regex_internal.h
+++ /dev/null
@@ -1,909 +0,0 @@
-/* Extended regular expression matching and search library.
-   Copyright (C) 2002-2013 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-   Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU General Public
-   License as published by the Free Software Foundation; either
-   version 3 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   General Public License for more details.
-
-   You should have received a copy of the GNU General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-#ifndef _REGEX_INTERNAL_H
-#define _REGEX_INTERNAL_H 1
-
-#include <assert.h>
-#include <ctype.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include <langinfo.h>
-#include <locale.h>
-#include <wchar.h>
-#include <wctype.h>
-#include <stdbool.h>
-#include <stdint.h>
-
-#ifdef _LIBC
-# include <bits/libc-lock.h>
-# define lock_define(name) __libc_lock_define (, name)
-# define lock_init(lock) (__libc_lock_init (lock), 0)
-# define lock_fini(lock) 0
-# define lock_lock(lock) __libc_lock_lock (lock)
-# define lock_unlock(lock) __libc_lock_unlock (lock)
-#elif defined GNULIB_LOCK
-# include "glthread/lock.h"
-  /* Use gl_lock_define if empty macro arguments are known to work.
-     Otherwise, fall back on less-portable substitutes.  */
-# if ((defined __GNUC__ && !defined __STRICT_ANSI__) \
-      || (defined __STDC_VERSION__ && 199901L <= __STDC_VERSION__))
-#  define lock_define(name) gl_lock_define (, name)
-# elif USE_POSIX_THREADS
-#  define lock_define(name) pthread_mutex_t name;
-# elif USE_PTH_THREADS
-#  define lock_define(name) pth_mutex_t name;
-# elif USE_SOLARIS_THREADS
-#  define lock_define(name) mutex_t name;
-# elif USE_WINDOWS_THREADS
-#  define lock_define(name) gl_lock_t name;
-# else
-#  define lock_define(name)
-# endif
-# define lock_init(lock) glthread_lock_init (&(lock))
-# define lock_fini(lock) glthread_lock_destroy (&(lock))
-# define lock_lock(lock) glthread_lock_lock (&(lock))
-# define lock_unlock(lock) glthread_lock_unlock (&(lock))
-#elif defined GNULIB_PTHREAD
-# include <pthread.h>
-# define lock_define(name) pthread_mutex_t name;
-# define lock_init(lock) pthread_mutex_init (&(lock), 0)
-# define lock_fini(lock) pthread_mutex_destroy (&(lock))
-# define lock_lock(lock) pthread_mutex_lock (&(lock))
-# define lock_unlock(lock) pthread_mutex_unlock (&(lock))
-#else
-# define lock_define(name)
-# define lock_init(lock) 0
-# define lock_fini(lock) ((void) 0)
-  /* The 'dfa' avoids an "unused variable 'dfa'" warning from GCC.  */
-# define lock_lock(lock) ((void) dfa)
-# define lock_unlock(lock) ((void) 0)
-#endif
-
-/* In case that the system doesn't have isblank().  */
-#if !defined _LIBC && ! (defined isblank || (HAVE_ISBLANK && HAVE_DECL_ISBLANK))
-# define isblank(ch) ((ch) == ' ' || (ch) == '\t')
-#endif
-
-#ifdef _LIBC
-# ifndef _RE_DEFINE_LOCALE_FUNCTIONS
-#  define _RE_DEFINE_LOCALE_FUNCTIONS 1
-#   include <locale/localeinfo.h>
-#   include <locale/elem-hash.h>
-#   include <locale/coll-lookup.h>
-# endif
-#endif
-
-/* This is for other GNU distributions with internationalized messages.  */
-#if (HAVE_LIBINTL_H && ENABLE_NLS) || defined _LIBC
-# include <libintl.h>
-# ifdef _LIBC
-#  undef gettext
-#  define gettext(msgid) \
-  __dcgettext (_libc_intl_domainname, msgid, LC_MESSAGES)
-# endif
-#else
-# define gettext(msgid) (msgid)
-#endif
-
-#ifndef gettext_noop
-/* This define is so xgettext can find the internationalizable
-   strings.  */
-# define gettext_noop(String) String
-#endif
-
-#if (defined MB_CUR_MAX && HAVE_WCTYPE_H && HAVE_ISWCTYPE && HAVE_WCSCOLL) || _LIBC
-# define RE_ENABLE_I18N
-#endif
-
-#if __GNUC__ >= 3
-# define BE(expr, val) __builtin_expect (expr, val)
-#else
-# define BE(expr, val) (expr)
-#endif
-
-/* Number of ASCII characters.  */
-#define ASCII_CHARS 0x80
-
-/* Number of single byte characters.  */
-#define SBC_MAX (UCHAR_MAX + 1)
-
-#define COLL_ELEM_LEN_MAX 8
-
-/* The character which represents newline.  */
-#define NEWLINE_CHAR '\n'
-#define WIDE_NEWLINE_CHAR L'\n'
-
-/* Rename to standard API for using out of glibc.  */
-#ifndef _LIBC
-# undef __wctype
-# undef __iswctype
-# define __wctype wctype
-# define __iswctype iswctype
-# define __btowc btowc
-# define __mbrtowc mbrtowc
-# define __wcrtomb wcrtomb
-# define __regfree regfree
-# define attribute_hidden
-#endif /* not _LIBC */
-
-#if __GNUC__ < 3 + (__GNUC_MINOR__ < 1)
-# define __attribute__(arg)
-#endif
-
-typedef __re_idx_t Idx;
-#ifdef _REGEX_LARGE_OFFSETS
-# define IDX_MAX (SIZE_MAX - 2)
-#else
-# define IDX_MAX INT_MAX
-#endif
-
-/* Special return value for failure to match.  */
-#define REG_MISSING ((Idx) -1)
-
-/* Special return value for internal error.  */
-#define REG_ERROR ((Idx) -2)
-
-/* Test whether N is a valid index, and is not one of the above.  */
-#ifdef _REGEX_LARGE_OFFSETS
-# define REG_VALID_INDEX(n) ((Idx) (n) < REG_ERROR)
-#else
-# define REG_VALID_INDEX(n) (0 <= (n))
-#endif
-
-/* Test whether N is a valid nonzero index.  */
-#ifdef _REGEX_LARGE_OFFSETS
-# define REG_VALID_NONZERO_INDEX(n) ((Idx) ((n) - 1) < (Idx) (REG_ERROR - 1))
-#else
-# define REG_VALID_NONZERO_INDEX(n) (0 < (n))
-#endif
-
-/* A hash value, suitable for computing hash tables.  */
-typedef __re_size_t re_hashval_t;
-
-/* An integer used to represent a set of bits.  It must be unsigned,
-   and must be at least as wide as unsigned int.  */
-typedef unsigned long int bitset_word_t;
-/* All bits set in a bitset_word_t.  */
-#define BITSET_WORD_MAX ULONG_MAX
-
-/* Number of bits in a bitset_word_t.  For portability to hosts with
-   padding bits, do not use '(sizeof (bitset_word_t) * CHAR_BIT)';
-   instead, deduce it directly from BITSET_WORD_MAX.  Avoid
-   greater-than-32-bit integers and unconditional shifts by more than
-   31 bits, as they're not portable.  */
-#if BITSET_WORD_MAX == 0xffffffffUL
-# define BITSET_WORD_BITS 32
-#elif BITSET_WORD_MAX >> 31 >> 4 == 1
-# define BITSET_WORD_BITS 36
-#elif BITSET_WORD_MAX >> 31 >> 16 == 1
-# define BITSET_WORD_BITS 48
-#elif BITSET_WORD_MAX >> 31 >> 28 == 1
-# define BITSET_WORD_BITS 60
-#elif BITSET_WORD_MAX >> 31 >> 31 >> 1 == 1
-# define BITSET_WORD_BITS 64
-#elif BITSET_WORD_MAX >> 31 >> 31 >> 9 == 1
-# define BITSET_WORD_BITS 72
-#elif BITSET_WORD_MAX >> 31 >> 31 >> 31 >> 31 >> 3 == 1
-# define BITSET_WORD_BITS 128
-#elif BITSET_WORD_MAX >> 31 >> 31 >> 31 >> 31 >> 31 >> 31 >> 31 >> 31 >> 7 == 1
-# define BITSET_WORD_BITS 256
-#elif BITSET_WORD_MAX >> 31 >> 31 >> 31 >> 31 >> 31 >> 31 >> 31 >> 31 >> 7 > 1
-# define BITSET_WORD_BITS 257 /* any value > SBC_MAX will do here */
-# if BITSET_WORD_BITS <= SBC_MAX
-#  error "Invalid SBC_MAX"
-# endif
-#else
-# error "Add case for new bitset_word_t size"
-#endif
-
-/* Number of bitset_word_t values in a bitset_t.  */
-#define BITSET_WORDS ((SBC_MAX + BITSET_WORD_BITS - 1) / BITSET_WORD_BITS)
-
-typedef bitset_word_t bitset_t[BITSET_WORDS];
-typedef bitset_word_t *re_bitset_ptr_t;
-typedef const bitset_word_t *re_const_bitset_ptr_t;
-
-#define PREV_WORD_CONSTRAINT 0x0001
-#define PREV_NOTWORD_CONSTRAINT 0x0002
-#define NEXT_WORD_CONSTRAINT 0x0004
-#define NEXT_NOTWORD_CONSTRAINT 0x0008
-#define PREV_NEWLINE_CONSTRAINT 0x0010
-#define NEXT_NEWLINE_CONSTRAINT 0x0020
-#define PREV_BEGBUF_CONSTRAINT 0x0040
-#define NEXT_ENDBUF_CONSTRAINT 0x0080
-#define WORD_DELIM_CONSTRAINT 0x0100
-#define NOT_WORD_DELIM_CONSTRAINT 0x0200
-
-typedef enum
-{
-  INSIDE_WORD = PREV_WORD_CONSTRAINT | NEXT_WORD_CONSTRAINT,
-  WORD_FIRST = PREV_NOTWORD_CONSTRAINT | NEXT_WORD_CONSTRAINT,
-  WORD_LAST = PREV_WORD_CONSTRAINT | NEXT_NOTWORD_CONSTRAINT,
-  INSIDE_NOTWORD = PREV_NOTWORD_CONSTRAINT | NEXT_NOTWORD_CONSTRAINT,
-  LINE_FIRST = PREV_NEWLINE_CONSTRAINT,
-  LINE_LAST = NEXT_NEWLINE_CONSTRAINT,
-  BUF_FIRST = PREV_BEGBUF_CONSTRAINT,
-  BUF_LAST = NEXT_ENDBUF_CONSTRAINT,
-  WORD_DELIM = WORD_DELIM_CONSTRAINT,
-  NOT_WORD_DELIM = NOT_WORD_DELIM_CONSTRAINT
-} re_context_type;
-
-typedef struct
-{
-  Idx alloc;
-  Idx nelem;
-  Idx *elems;
-} re_node_set;
-
-typedef enum
-{
-  NON_TYPE = 0,
-
-  /* Node type, These are used by token, node, tree.  */
-  CHARACTER = 1,
-  END_OF_RE = 2,
-  SIMPLE_BRACKET = 3,
-  OP_BACK_REF = 4,
-  OP_PERIOD = 5,
-#ifdef RE_ENABLE_I18N
-  COMPLEX_BRACKET = 6,
-  OP_UTF8_PERIOD = 7,
-#endif /* RE_ENABLE_I18N */
-
-  /* We define EPSILON_BIT as a macro so that OP_OPEN_SUBEXP is used
-     when the debugger shows values of this enum type.  */
-#define EPSILON_BIT 8
-  OP_OPEN_SUBEXP = EPSILON_BIT | 0,
-  OP_CLOSE_SUBEXP = EPSILON_BIT | 1,
-  OP_ALT = EPSILON_BIT | 2,
-  OP_DUP_ASTERISK = EPSILON_BIT | 3,
-  ANCHOR = EPSILON_BIT | 4,
-
-  /* Tree type, these are used only by tree. */
-  CONCAT = 16,
-  SUBEXP = 17,
-
-  /* Token type, these are used only by token.  */
-  OP_DUP_PLUS = 18,
-  OP_DUP_QUESTION,
-  OP_OPEN_BRACKET,
-  OP_CLOSE_BRACKET,
-  OP_CHARSET_RANGE,
-  OP_OPEN_DUP_NUM,
-  OP_CLOSE_DUP_NUM,
-  OP_NON_MATCH_LIST,
-  OP_OPEN_COLL_ELEM,
-  OP_CLOSE_COLL_ELEM,
-  OP_OPEN_EQUIV_CLASS,
-  OP_CLOSE_EQUIV_CLASS,
-  OP_OPEN_CHAR_CLASS,
-  OP_CLOSE_CHAR_CLASS,
-  OP_WORD,
-  OP_NOTWORD,
-  OP_SPACE,
-  OP_NOTSPACE,
-  BACK_SLASH
-
-} re_token_type_t;
-
-#ifdef RE_ENABLE_I18N
-typedef struct
-{
-  /* Multibyte characters.  */
-  wchar_t *mbchars;
-
-  /* Collating symbols.  */
-# ifdef _LIBC
-  int32_t *coll_syms;
-# endif
-
-  /* Equivalence classes. */
-# ifdef _LIBC
-  int32_t *equiv_classes;
-# endif
-
-  /* Range expressions. */
-# ifdef _LIBC
-  uint32_t *range_starts;
-  uint32_t *range_ends;
-# else /* not _LIBC */
-  wchar_t *range_starts;
-  wchar_t *range_ends;
-# endif /* not _LIBC */
-
-  /* Character classes. */
-  wctype_t *char_classes;
-
-  /* If this character set is the non-matching list.  */
-  unsigned int non_match : 1;
-
-  /* # of multibyte characters.  */
-  Idx nmbchars;
-
-  /* # of collating symbols.  */
-  Idx ncoll_syms;
-
-  /* # of equivalence classes. */
-  Idx nequiv_classes;
-
-  /* # of range expressions. */
-  Idx nranges;
-
-  /* # of character classes. */
-  Idx nchar_classes;
-} re_charset_t;
-#endif /* RE_ENABLE_I18N */
-
-typedef struct
-{
-  union
-  {
-    unsigned char c;		/* for CHARACTER */
-    re_bitset_ptr_t sbcset;	/* for SIMPLE_BRACKET */
-#ifdef RE_ENABLE_I18N
-    re_charset_t *mbcset;	/* for COMPLEX_BRACKET */
-#endif /* RE_ENABLE_I18N */
-    Idx idx;			/* for BACK_REF */
-    re_context_type ctx_type;	/* for ANCHOR */
-  } opr;
-#if __GNUC__ >= 2 && !defined __STRICT_ANSI__
-  re_token_type_t type : 8;
-#else
-  re_token_type_t type;
-#endif
-  unsigned int constraint : 10;	/* context constraint */
-  unsigned int duplicated : 1;
-  unsigned int opt_subexp : 1;
-#ifdef RE_ENABLE_I18N
-  unsigned int accept_mb : 1;
-  /* These 2 bits can be moved into the union if needed (e.g. if running out
-     of bits; move opr.c to opr.c.c and move the flags to opr.c.flags).  */
-  unsigned int mb_partial : 1;
-#endif
-  unsigned int word_char : 1;
-} re_token_t;
-
-#define IS_EPSILON_NODE(type) ((type) & EPSILON_BIT)
-
-struct re_string_t
-{
-  /* Indicate the raw buffer which is the original string passed as an
-     argument of regexec(), re_search(), etc..  */
-  const unsigned char *raw_mbs;
-  /* Store the multibyte string.  In case of "case insensitive mode" like
-     REG_ICASE, upper cases of the string are stored, otherwise MBS points
-     the same address that RAW_MBS points.  */
-  unsigned char *mbs;
-#ifdef RE_ENABLE_I18N
-  /* Store the wide character string which is corresponding to MBS.  */
-  wint_t *wcs;
-  Idx *offsets;
-  mbstate_t cur_state;
-#endif
-  /* Index in RAW_MBS.  Each character mbs[i] corresponds to
-     raw_mbs[raw_mbs_idx + i].  */
-  Idx raw_mbs_idx;
-  /* The length of the valid characters in the buffers.  */
-  Idx valid_len;
-  /* The corresponding number of bytes in raw_mbs array.  */
-  Idx valid_raw_len;
-  /* The length of the buffers MBS and WCS.  */
-  Idx bufs_len;
-  /* The index in MBS, which is updated by re_string_fetch_byte.  */
-  Idx cur_idx;
-  /* length of RAW_MBS array.  */
-  Idx raw_len;
-  /* This is RAW_LEN - RAW_MBS_IDX + VALID_LEN - VALID_RAW_LEN.  */
-  Idx len;
-  /* End of the buffer may be shorter than its length in the cases such
-     as re_match_2, re_search_2.  Then, we use STOP for end of the buffer
-     instead of LEN.  */
-  Idx raw_stop;
-  /* This is RAW_STOP - RAW_MBS_IDX adjusted through OFFSETS.  */
-  Idx stop;
-
-  /* The context of mbs[0].  We store the context independently, since
-     the context of mbs[0] may be different from raw_mbs[0], which is
-     the beginning of the input string.  */
-  unsigned int tip_context;
-  /* The translation passed as a part of an argument of re_compile_pattern.  */
-  RE_TRANSLATE_TYPE trans;
-  /* Copy of re_dfa_t's word_char.  */
-  re_const_bitset_ptr_t word_char;
-  /* true if REG_ICASE.  */
-  unsigned char icase;
-  unsigned char is_utf8;
-  unsigned char map_notascii;
-  unsigned char mbs_allocated;
-  unsigned char offsets_needed;
-  unsigned char newline_anchor;
-  unsigned char word_ops_used;
-  int mb_cur_max;
-};
-typedef struct re_string_t re_string_t;
-
-
-struct re_dfa_t;
-typedef struct re_dfa_t re_dfa_t;
-
-#ifndef _LIBC
-# define internal_function
-#endif
-
-#ifndef NOT_IN_libc
-static reg_errcode_t re_string_realloc_buffers (re_string_t *pstr,
-						Idx new_buf_len)
-     internal_function;
-# ifdef RE_ENABLE_I18N
-static void build_wcs_buffer (re_string_t *pstr) internal_function;
-static reg_errcode_t build_wcs_upper_buffer (re_string_t *pstr)
-  internal_function;
-# endif /* RE_ENABLE_I18N */
-static void build_upper_buffer (re_string_t *pstr) internal_function;
-static void re_string_translate_buffer (re_string_t *pstr) internal_function;
-static unsigned int re_string_context_at (const re_string_t *input, Idx idx,
-					  int eflags)
-     internal_function __attribute__ ((pure));
-#endif
-#define re_string_peek_byte(pstr, offset) \
-  ((pstr)->mbs[(pstr)->cur_idx + offset])
-#define re_string_fetch_byte(pstr) \
-  ((pstr)->mbs[(pstr)->cur_idx++])
-#define re_string_first_byte(pstr, idx) \
-  ((idx) == (pstr)->valid_len || (pstr)->wcs[idx] != WEOF)
-#define re_string_is_single_byte_char(pstr, idx) \
-  ((pstr)->wcs[idx] != WEOF && ((pstr)->valid_len == (idx) + 1 \
-				|| (pstr)->wcs[(idx) + 1] != WEOF))
-#define re_string_eoi(pstr) ((pstr)->stop <= (pstr)->cur_idx)
-#define re_string_cur_idx(pstr) ((pstr)->cur_idx)
-#define re_string_get_buffer(pstr) ((pstr)->mbs)
-#define re_string_length(pstr) ((pstr)->len)
-#define re_string_byte_at(pstr,idx) ((pstr)->mbs[idx])
-#define re_string_skip_bytes(pstr,idx) ((pstr)->cur_idx += (idx))
-#define re_string_set_index(pstr,idx) ((pstr)->cur_idx = (idx))
-
-#if defined _LIBC || HAVE_ALLOCA
-# include "palloca.h"
-#endif
-
-#ifndef _LIBC
-# if HAVE_ALLOCA
-/* The OS usually guarantees only one guard page at the bottom of the stack,
-   and a page size can be as small as 4096 bytes.  So we cannot safely
-   allocate anything larger than 4096 bytes.  Also care for the possibility
-   of a few compiler-allocated temporary stack slots.  */
-#  define __libc_use_alloca(n) ((n) < 4032)
-# else
-/* alloca is implemented with malloc, so just use malloc.  */
-#  define __libc_use_alloca(n) 0
-#  undef alloca
-#  define alloca(n) malloc (n)
-# endif
-#endif
-
-#ifdef _LIBC
-# define MALLOC_0_IS_NONNULL 1
-#elif !defined MALLOC_0_IS_NONNULL
-# define MALLOC_0_IS_NONNULL 0
-#endif
-
-#ifndef MAX
-# define MAX(a,b) ((a) < (b) ? (b) : (a))
-#endif
-#ifndef MIN
-# define MIN(a,b) ((a) < (b) ? (a) : (b))
-#endif
-
-#define re_malloc(t,n) ((t *) malloc ((n) * sizeof (t)))
-#define re_realloc(p,t,n) ((t *) realloc (p, (n) * sizeof (t)))
-#define re_free(p) free (p)
-
-struct bin_tree_t
-{
-  struct bin_tree_t *parent;
-  struct bin_tree_t *left;
-  struct bin_tree_t *right;
-  struct bin_tree_t *first;
-  struct bin_tree_t *next;
-
-  re_token_t token;
-
-  /* 'node_idx' is the index in dfa->nodes, if 'type' == 0.
-     Otherwise 'type' indicate the type of this node.  */
-  Idx node_idx;
-};
-typedef struct bin_tree_t bin_tree_t;
-
-#define BIN_TREE_STORAGE_SIZE \
-  ((1024 - sizeof (void *)) / sizeof (bin_tree_t))
-
-struct bin_tree_storage_t
-{
-  struct bin_tree_storage_t *next;
-  bin_tree_t data[BIN_TREE_STORAGE_SIZE];
-};
-typedef struct bin_tree_storage_t bin_tree_storage_t;
-
-#define CONTEXT_WORD 1
-#define CONTEXT_NEWLINE (CONTEXT_WORD << 1)
-#define CONTEXT_BEGBUF (CONTEXT_NEWLINE << 1)
-#define CONTEXT_ENDBUF (CONTEXT_BEGBUF << 1)
-
-#define IS_WORD_CONTEXT(c) ((c) & CONTEXT_WORD)
-#define IS_NEWLINE_CONTEXT(c) ((c) & CONTEXT_NEWLINE)
-#define IS_BEGBUF_CONTEXT(c) ((c) & CONTEXT_BEGBUF)
-#define IS_ENDBUF_CONTEXT(c) ((c) & CONTEXT_ENDBUF)
-#define IS_ORDINARY_CONTEXT(c) ((c) == 0)
-
-#define IS_WORD_CHAR(ch) (isalnum (ch) || (ch) == '_')
-#define IS_NEWLINE(ch) ((ch) == NEWLINE_CHAR)
-#define IS_WIDE_WORD_CHAR(ch) (iswalnum (ch) || (ch) == L'_')
-#define IS_WIDE_NEWLINE(ch) ((ch) == WIDE_NEWLINE_CHAR)
-
-#define NOT_SATISFY_PREV_CONSTRAINT(constraint,context) \
- ((((constraint) & PREV_WORD_CONSTRAINT) && !IS_WORD_CONTEXT (context)) \
-  || ((constraint & PREV_NOTWORD_CONSTRAINT) && IS_WORD_CONTEXT (context)) \
-  || ((constraint & PREV_NEWLINE_CONSTRAINT) && !IS_NEWLINE_CONTEXT (context))\
-  || ((constraint & PREV_BEGBUF_CONSTRAINT) && !IS_BEGBUF_CONTEXT (context)))
-
-#define NOT_SATISFY_NEXT_CONSTRAINT(constraint,context) \
- ((((constraint) & NEXT_WORD_CONSTRAINT) && !IS_WORD_CONTEXT (context)) \
-  || (((constraint) & NEXT_NOTWORD_CONSTRAINT) && IS_WORD_CONTEXT (context)) \
-  || (((constraint) & NEXT_NEWLINE_CONSTRAINT) && !IS_NEWLINE_CONTEXT (context)) \
-  || (((constraint) & NEXT_ENDBUF_CONSTRAINT) && !IS_ENDBUF_CONTEXT (context)))
-
-struct re_dfastate_t
-{
-  re_hashval_t hash;
-  re_node_set nodes;
-  re_node_set non_eps_nodes;
-  re_node_set inveclosure;
-  re_node_set *entrance_nodes;
-  struct re_dfastate_t **trtable, **word_trtable;
-  unsigned int context : 4;
-  unsigned int halt : 1;
-  /* If this state can accept "multi byte".
-     Note that we refer to multibyte characters, and multi character
-     collating elements as "multi byte".  */
-  unsigned int accept_mb : 1;
-  /* If this state has backreference node(s).  */
-  unsigned int has_backref : 1;
-  unsigned int has_constraint : 1;
-};
-typedef struct re_dfastate_t re_dfastate_t;
-
-struct re_state_table_entry
-{
-  Idx num;
-  Idx alloc;
-  re_dfastate_t **array;
-};
-
-/* Array type used in re_sub_match_last_t and re_sub_match_top_t.  */
-
-typedef struct
-{
-  Idx next_idx;
-  Idx alloc;
-  re_dfastate_t **array;
-} state_array_t;
-
-/* Store information about the node NODE whose type is OP_CLOSE_SUBEXP.  */
-
-typedef struct
-{
-  Idx node;
-  Idx str_idx; /* The position NODE match at.  */
-  state_array_t path;
-} re_sub_match_last_t;
-
-/* Store information about the node NODE whose type is OP_OPEN_SUBEXP.
-   And information about the node, whose type is OP_CLOSE_SUBEXP,
-   corresponding to NODE is stored in LASTS.  */
-
-typedef struct
-{
-  Idx str_idx;
-  Idx node;
-  state_array_t *path;
-  Idx alasts; /* Allocation size of LASTS.  */
-  Idx nlasts; /* The number of LASTS.  */
-  re_sub_match_last_t **lasts;
-} re_sub_match_top_t;
-
-struct re_backref_cache_entry
-{
-  Idx node;
-  Idx str_idx;
-  Idx subexp_from;
-  Idx subexp_to;
-  char more;
-  char unused;
-  unsigned short int eps_reachable_subexps_map;
-};
-
-typedef struct
-{
-  /* The string object corresponding to the input string.  */
-  re_string_t input;
-#if defined _LIBC || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)
-  const re_dfa_t *const dfa;
-#else
-  const re_dfa_t *dfa;
-#endif
-  /* EFLAGS of the argument of regexec.  */
-  int eflags;
-  /* Where the matching ends.  */
-  Idx match_last;
-  Idx last_node;
-  /* The state log used by the matcher.  */
-  re_dfastate_t **state_log;
-  Idx state_log_top;
-  /* Back reference cache.  */
-  Idx nbkref_ents;
-  Idx abkref_ents;
-  struct re_backref_cache_entry *bkref_ents;
-  int max_mb_elem_len;
-  Idx nsub_tops;
-  Idx asub_tops;
-  re_sub_match_top_t **sub_tops;
-} re_match_context_t;
-
-typedef struct
-{
-  re_dfastate_t **sifted_states;
-  re_dfastate_t **limited_states;
-  Idx last_node;
-  Idx last_str_idx;
-  re_node_set limits;
-} re_sift_context_t;
-
-struct re_fail_stack_ent_t
-{
-  Idx idx;
-  Idx node;
-  regmatch_t *regs;
-  re_node_set eps_via_nodes;
-};
-
-struct re_fail_stack_t
-{
-  Idx num;
-  Idx alloc;
-  struct re_fail_stack_ent_t *stack;
-};
-
-struct re_dfa_t
-{
-  re_token_t *nodes;
-  size_t nodes_alloc;
-  size_t nodes_len;
-  Idx *nexts;
-  Idx *org_indices;
-  re_node_set *edests;
-  re_node_set *eclosures;
-  re_node_set *inveclosures;
-  struct re_state_table_entry *state_table;
-  re_dfastate_t *init_state;
-  re_dfastate_t *init_state_word;
-  re_dfastate_t *init_state_nl;
-  re_dfastate_t *init_state_begbuf;
-  bin_tree_t *str_tree;
-  bin_tree_storage_t *str_tree_storage;
-  re_bitset_ptr_t sb_char;
-  int str_tree_storage_idx;
-
-  /* number of subexpressions 're_nsub' is in regex_t.  */
-  re_hashval_t state_hash_mask;
-  Idx init_node;
-  Idx nbackref; /* The number of backreference in this dfa.  */
-
-  /* Bitmap expressing which backreference is used.  */
-  bitset_word_t used_bkref_map;
-  bitset_word_t completed_bkref_map;
-
-  unsigned int has_plural_match : 1;
-  /* If this dfa has "multibyte node", which is a backreference or
-     a node which can accept multibyte character or multi character
-     collating element.  */
-  unsigned int has_mb_node : 1;
-  unsigned int is_utf8 : 1;
-  unsigned int map_notascii : 1;
-  unsigned int word_ops_used : 1;
-  int mb_cur_max;
-  bitset_t word_char;
-  reg_syntax_t syntax;
-  Idx *subexp_map;
-#ifdef DEBUG
-  char* re_str;
-#endif
-  lock_define (lock)
-};
-
-#define re_node_set_init_empty(set) memset (set, '\0', sizeof (re_node_set))
-#define re_node_set_remove(set,id) \
-  (re_node_set_remove_at (set, re_node_set_contains (set, id) - 1))
-#define re_node_set_empty(p) ((p)->nelem = 0)
-#define re_node_set_free(set) re_free ((set)->elems)
-
-
-typedef enum
-{
-  SB_CHAR,
-  MB_CHAR,
-  EQUIV_CLASS,
-  COLL_SYM,
-  CHAR_CLASS
-} bracket_elem_type;
-
-typedef struct
-{
-  bracket_elem_type type;
-  union
-  {
-    unsigned char ch;
-    unsigned char *name;
-    wchar_t wch;
-  } opr;
-} bracket_elem_t;
-
-
-/* Functions for bitset_t operation.  */
-
-static void
-bitset_set (bitset_t set, Idx i)
-{
-  set[i / BITSET_WORD_BITS] |= (bitset_word_t) 1 << i % BITSET_WORD_BITS;
-}
-
-static void
-bitset_clear (bitset_t set, Idx i)
-{
-  set[i / BITSET_WORD_BITS] &= ~ ((bitset_word_t) 1 << i % BITSET_WORD_BITS);
-}
-
-static bool
-bitset_contain (const bitset_t set, Idx i)
-{
-  return (set[i / BITSET_WORD_BITS] >> i % BITSET_WORD_BITS) & 1;
-}
-
-static void
-bitset_empty (bitset_t set)
-{
-  memset (set, '\0', sizeof (bitset_t));
-}
-
-static void
-bitset_set_all (bitset_t set)
-{
-  memset (set, -1, sizeof (bitset_word_t) * (SBC_MAX / BITSET_WORD_BITS));
-  if (SBC_MAX % BITSET_WORD_BITS != 0)
-    set[BITSET_WORDS - 1] =
-      ((bitset_word_t) 1 << SBC_MAX % BITSET_WORD_BITS) - 1;
-}
-
-static void
-bitset_copy (bitset_t dest, const bitset_t src)
-{
-  memcpy (dest, src, sizeof (bitset_t));
-}
-
-static void __attribute__ ((unused))
-bitset_not (bitset_t set)
-{
-  int bitset_i;
-  for (bitset_i = 0; bitset_i < SBC_MAX / BITSET_WORD_BITS; ++bitset_i)
-    set[bitset_i] = ~set[bitset_i];
-  if (SBC_MAX % BITSET_WORD_BITS != 0)
-    set[BITSET_WORDS - 1] =
-      ((((bitset_word_t) 1 << SBC_MAX % BITSET_WORD_BITS) - 1)
-       & ~set[BITSET_WORDS - 1]);
-}
-
-static void __attribute__ ((unused))
-bitset_merge (bitset_t dest, const bitset_t src)
-{
-  int bitset_i;
-  for (bitset_i = 0; bitset_i < BITSET_WORDS; ++bitset_i)
-    dest[bitset_i] |= src[bitset_i];
-}
-
-static void __attribute__ ((unused))
-bitset_mask (bitset_t dest, const bitset_t src)
-{
-  int bitset_i;
-  for (bitset_i = 0; bitset_i < BITSET_WORDS; ++bitset_i)
-    dest[bitset_i] &= src[bitset_i];
-}
-
-#ifdef RE_ENABLE_I18N
-/* Functions for re_string.  */
-static int
-internal_function __attribute__ ((pure, unused))
-re_string_char_size_at (const re_string_t *pstr, Idx idx)
-{
-  int byte_idx;
-  if (pstr->mb_cur_max == 1)
-    return 1;
-  for (byte_idx = 1; idx + byte_idx < pstr->valid_len; ++byte_idx)
-    if (pstr->wcs[idx + byte_idx] != WEOF)
-      break;
-  return byte_idx;
-}
-
-static wint_t
-internal_function __attribute__ ((pure, unused))
-re_string_wchar_at (const re_string_t *pstr, Idx idx)
-{
-  if (pstr->mb_cur_max == 1)
-    return (wint_t) pstr->mbs[idx];
-  return (wint_t) pstr->wcs[idx];
-}
-
-# ifndef NOT_IN_libc
-static int
-internal_function __attribute__ ((pure, unused))
-re_string_elem_size_at (const re_string_t *pstr, Idx idx)
-{
-#  ifdef _LIBC
-  const unsigned char *p, *extra;
-  const int32_t *table, *indirect;
-#   include <locale/weight.h>
-  uint_fast32_t nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES);
-
-  if (nrules != 0)
-    {
-      table = (const int32_t *) _NL_CURRENT (LC_COLLATE, _NL_COLLATE_TABLEMB);
-      extra = (const unsigned char *)
-	_NL_CURRENT (LC_COLLATE, _NL_COLLATE_EXTRAMB);
-      indirect = (const int32_t *) _NL_CURRENT (LC_COLLATE,
-						_NL_COLLATE_INDIRECTMB);
-      p = pstr->mbs + idx;
-      findidx (&p, pstr->len - idx);
-      return p - pstr->mbs - idx;
-    }
-  else
-#  endif /* _LIBC */
-    return 1;
-}
-# endif
-#endif /* RE_ENABLE_I18N */
-
-#ifndef __GNUC_PREREQ
-# if defined __GNUC__ && defined __GNUC_MINOR__
-#  define __GNUC_PREREQ(maj, min) \
-         ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
-# else
-#  define __GNUC_PREREQ(maj, min) 0
-# endif
-#endif
-
-#if __GNUC_PREREQ (3,4)
-# undef __attribute_warn_unused_result__
-# define __attribute_warn_unused_result__ \
-   __attribute__ ((__warn_unused_result__))
-#else
-# define __attribute_warn_unused_result__ /* empty */
-#endif
-
-#endif /*  _REGEX_INTERNAL_H */
diff --git a/contrib/tools/bison/lib/regexec.c b/contrib/tools/bison/lib/regexec.c
deleted file mode 100644
index d29d442baf..0000000000
--- a/contrib/tools/bison/lib/regexec.c
+++ /dev/null
@@ -1,4410 +0,0 @@
-/* Extended regular expression matching and search library.
-   Copyright (C) 2002-2013 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-   Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU General Public
-   License as published by the Free Software Foundation; either
-   version 3 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   General Public License for more details.
-
-   You should have received a copy of the GNU General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-static reg_errcode_t match_ctx_init (re_match_context_t *cache, int eflags,
-				     Idx n) internal_function;
-static void match_ctx_clean (re_match_context_t *mctx) internal_function;
-static void match_ctx_free (re_match_context_t *cache) internal_function;
-static reg_errcode_t match_ctx_add_entry (re_match_context_t *cache, Idx node,
-					  Idx str_idx, Idx from, Idx to)
-     internal_function;
-static Idx search_cur_bkref_entry (const re_match_context_t *mctx, Idx str_idx)
-     internal_function;
-static reg_errcode_t match_ctx_add_subtop (re_match_context_t *mctx, Idx node,
-					   Idx str_idx) internal_function;
-static re_sub_match_last_t * match_ctx_add_sublast (re_sub_match_top_t *subtop,
-						    Idx node, Idx str_idx)
-     internal_function;
-static void sift_ctx_init (re_sift_context_t *sctx, re_dfastate_t **sifted_sts,
-			   re_dfastate_t **limited_sts, Idx last_node,
-			   Idx last_str_idx)
-     internal_function;
-static reg_errcode_t re_search_internal (const regex_t *preg,
-					 const char *string, Idx length,
-					 Idx start, Idx last_start, Idx stop,
-					 size_t nmatch, regmatch_t pmatch[],
-					 int eflags) internal_function;
-static regoff_t re_search_2_stub (struct re_pattern_buffer *bufp,
-				  const char *string1, Idx length1,
-				  const char *string2, Idx length2,
-				  Idx start, regoff_t range,
-				  struct re_registers *regs,
-				  Idx stop, bool ret_len) internal_function;
-static regoff_t re_search_stub (struct re_pattern_buffer *bufp,
-				const char *string, Idx length, Idx start,
-				regoff_t range, Idx stop,
-				struct re_registers *regs,
-				bool ret_len) internal_function;
-static unsigned re_copy_regs (struct re_registers *regs, regmatch_t *pmatch,
-                              Idx nregs, int regs_allocated) internal_function;
-static reg_errcode_t prune_impossible_nodes (re_match_context_t *mctx)
-     internal_function;
-static Idx check_matching (re_match_context_t *mctx, bool fl_longest_match,
-			   Idx *p_match_first) internal_function;
-static Idx check_halt_state_context (const re_match_context_t *mctx,
-				     const re_dfastate_t *state, Idx idx)
-     internal_function;
-static void update_regs (const re_dfa_t *dfa, regmatch_t *pmatch,
-			 regmatch_t *prev_idx_match, Idx cur_node,
-			 Idx cur_idx, Idx nmatch) internal_function;
-static reg_errcode_t push_fail_stack (struct re_fail_stack_t *fs,
-				      Idx str_idx, Idx dest_node, Idx nregs,
-				      regmatch_t *regs,
-				      re_node_set *eps_via_nodes)
-     internal_function;
-static reg_errcode_t set_regs (const regex_t *preg,
-			       const re_match_context_t *mctx,
-			       size_t nmatch, regmatch_t *pmatch,
-			       bool fl_backtrack) internal_function;
-static reg_errcode_t free_fail_stack_return (struct re_fail_stack_t *fs)
-     internal_function;
-
-#ifdef RE_ENABLE_I18N
-static int sift_states_iter_mb (const re_match_context_t *mctx,
-				re_sift_context_t *sctx,
-				Idx node_idx, Idx str_idx, Idx max_str_idx)
-     internal_function;
-#endif /* RE_ENABLE_I18N */
-static reg_errcode_t sift_states_backward (const re_match_context_t *mctx,
-					   re_sift_context_t *sctx)
-     internal_function;
-static reg_errcode_t build_sifted_states (const re_match_context_t *mctx,
-					  re_sift_context_t *sctx, Idx str_idx,
-					  re_node_set *cur_dest)
-     internal_function;
-static reg_errcode_t update_cur_sifted_state (const re_match_context_t *mctx,
-					      re_sift_context_t *sctx,
-					      Idx str_idx,
-					      re_node_set *dest_nodes)
-     internal_function;
-static reg_errcode_t add_epsilon_src_nodes (const re_dfa_t *dfa,
-					    re_node_set *dest_nodes,
-					    const re_node_set *candidates)
-     internal_function;
-static bool check_dst_limits (const re_match_context_t *mctx,
-			      const re_node_set *limits,
-			      Idx dst_node, Idx dst_idx, Idx src_node,
-			      Idx src_idx) internal_function;
-static int check_dst_limits_calc_pos_1 (const re_match_context_t *mctx,
-					int boundaries, Idx subexp_idx,
-					Idx from_node, Idx bkref_idx)
-     internal_function;
-static int check_dst_limits_calc_pos (const re_match_context_t *mctx,
-				      Idx limit, Idx subexp_idx,
-				      Idx node, Idx str_idx,
-				      Idx bkref_idx) internal_function;
-static reg_errcode_t check_subexp_limits (const re_dfa_t *dfa,
-					  re_node_set *dest_nodes,
-					  const re_node_set *candidates,
-					  re_node_set *limits,
-					  struct re_backref_cache_entry *bkref_ents,
-					  Idx str_idx) internal_function;
-static reg_errcode_t sift_states_bkref (const re_match_context_t *mctx,
-					re_sift_context_t *sctx,
-					Idx str_idx, const re_node_set *candidates)
-     internal_function;
-static reg_errcode_t merge_state_array (const re_dfa_t *dfa,
-					re_dfastate_t **dst,
-					re_dfastate_t **src, Idx num)
-     internal_function;
-static re_dfastate_t *find_recover_state (reg_errcode_t *err,
-					 re_match_context_t *mctx) internal_function;
-static re_dfastate_t *transit_state (reg_errcode_t *err,
-				     re_match_context_t *mctx,
-				     re_dfastate_t *state) internal_function;
-static re_dfastate_t *merge_state_with_log (reg_errcode_t *err,
-					    re_match_context_t *mctx,
-					    re_dfastate_t *next_state)
-     internal_function;
-static reg_errcode_t check_subexp_matching_top (re_match_context_t *mctx,
-						re_node_set *cur_nodes,
-						Idx str_idx) internal_function;
-#if 0
-static re_dfastate_t *transit_state_sb (reg_errcode_t *err,
-					re_match_context_t *mctx,
-					re_dfastate_t *pstate)
-     internal_function;
-#endif
-#ifdef RE_ENABLE_I18N
-static reg_errcode_t transit_state_mb (re_match_context_t *mctx,
-				       re_dfastate_t *pstate)
-     internal_function;
-#endif /* RE_ENABLE_I18N */
-static reg_errcode_t transit_state_bkref (re_match_context_t *mctx,
-					  const re_node_set *nodes)
-     internal_function;
-static reg_errcode_t get_subexp (re_match_context_t *mctx,
-				 Idx bkref_node, Idx bkref_str_idx)
-     internal_function;
-static reg_errcode_t get_subexp_sub (re_match_context_t *mctx,
-				     const re_sub_match_top_t *sub_top,
-				     re_sub_match_last_t *sub_last,
-				     Idx bkref_node, Idx bkref_str)
-     internal_function;
-static Idx find_subexp_node (const re_dfa_t *dfa, const re_node_set *nodes,
-			     Idx subexp_idx, int type) internal_function;
-static reg_errcode_t check_arrival (re_match_context_t *mctx,
-				    state_array_t *path, Idx top_node,
-				    Idx top_str, Idx last_node, Idx last_str,
-				    int type) internal_function;
-static reg_errcode_t check_arrival_add_next_nodes (re_match_context_t *mctx,
-						   Idx str_idx,
-						   re_node_set *cur_nodes,
-						   re_node_set *next_nodes)
-     internal_function;
-static reg_errcode_t check_arrival_expand_ecl (const re_dfa_t *dfa,
-					       re_node_set *cur_nodes,
-					       Idx ex_subexp, int type)
-     internal_function;
-static reg_errcode_t check_arrival_expand_ecl_sub (const re_dfa_t *dfa,
-						   re_node_set *dst_nodes,
-						   Idx target, Idx ex_subexp,
-						   int type) internal_function;
-static reg_errcode_t expand_bkref_cache (re_match_context_t *mctx,
-					 re_node_set *cur_nodes, Idx cur_str,
-					 Idx subexp_num, int type)
-     internal_function;
-static bool build_trtable (const re_dfa_t *dfa,
-			   re_dfastate_t *state) internal_function;
-#ifdef RE_ENABLE_I18N
-static int check_node_accept_bytes (const re_dfa_t *dfa, Idx node_idx,
-				    const re_string_t *input, Idx idx)
-     internal_function;
-# ifdef _LIBC
-static unsigned int find_collation_sequence_value (const unsigned char *mbs,
-						   size_t name_len)
-     internal_function;
-# endif /* _LIBC */
-#endif /* RE_ENABLE_I18N */
-static Idx group_nodes_into_DFAstates (const re_dfa_t *dfa,
-				       const re_dfastate_t *state,
-				       re_node_set *states_node,
-				       bitset_t *states_ch) internal_function;
-static bool check_node_accept (const re_match_context_t *mctx,
-			       const re_token_t *node, Idx idx)
-     internal_function;
-static reg_errcode_t extend_buffers (re_match_context_t *mctx, int min_len)
-     internal_function;
-
-/* Entry point for POSIX code.  */
-
-/* regexec searches for a given pattern, specified by PREG, in the
-   string STRING.
-
-   If NMATCH is zero or REG_NOSUB was set in the cflags argument to
-   'regcomp', we ignore PMATCH.  Otherwise, we assume PMATCH has at
-   least NMATCH elements, and we set them to the offsets of the
-   corresponding matched substrings.
-
-   EFLAGS specifies "execution flags" which affect matching: if
-   REG_NOTBOL is set, then ^ does not match at the beginning of the
-   string; if REG_NOTEOL is set, then $ does not match at the end.
-
-   We return 0 if we find a match and REG_NOMATCH if not.  */
-
-int
-regexec (preg, string, nmatch, pmatch, eflags)
-    const regex_t *_Restrict_ preg;
-    const char *_Restrict_ string;
-    size_t nmatch;
-    regmatch_t pmatch[_Restrict_arr_];
-    int eflags;
-{
-  reg_errcode_t err;
-  Idx start, length;
-  re_dfa_t *dfa = preg->buffer;
-
-  if (eflags & ~(REG_NOTBOL | REG_NOTEOL | REG_STARTEND))
-    return REG_BADPAT;
-
-  if (eflags & REG_STARTEND)
-    {
-      start = pmatch[0].rm_so;
-      length = pmatch[0].rm_eo;
-    }
-  else
-    {
-      start = 0;
-      length = strlen (string);
-    }
-
-  lock_lock (dfa->lock);
-  if (preg->no_sub)
-    err = re_search_internal (preg, string, length, start, length,
-			      length, 0, NULL, eflags);
-  else
-    err = re_search_internal (preg, string, length, start, length,
-			      length, nmatch, pmatch, eflags);
-  lock_unlock (dfa->lock);
-  return err != REG_NOERROR;
-}
-
-#ifdef _LIBC
-# include <shlib-compat.h>
-versioned_symbol (libc, __regexec, regexec, GLIBC_2_3_4);
-
-# if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_3_4)
-__typeof__ (__regexec) __compat_regexec;
-
-int
-attribute_compat_text_section
-__compat_regexec (const regex_t *_Restrict_ preg,
-		  const char *_Restrict_ string, size_t nmatch,
-		  regmatch_t pmatch[], int eflags)
-{
-  return regexec (preg, string, nmatch, pmatch,
-		  eflags & (REG_NOTBOL | REG_NOTEOL));
-}
-compat_symbol (libc, __compat_regexec, regexec, GLIBC_2_0);
-# endif
-#endif
-
-/* Entry points for GNU code.  */
-
-/* re_match, re_search, re_match_2, re_search_2
-
-   The former two functions operate on STRING with length LENGTH,
-   while the later two operate on concatenation of STRING1 and STRING2
-   with lengths LENGTH1 and LENGTH2, respectively.
-
-   re_match() matches the compiled pattern in BUFP against the string,
-   starting at index START.
-
-   re_search() first tries matching at index START, then it tries to match
-   starting from index START + 1, and so on.  The last start position tried
-   is START + RANGE.  (Thus RANGE = 0 forces re_search to operate the same
-   way as re_match().)
-
-   The parameter STOP of re_{match,search}_2 specifies that no match exceeding
-   the first STOP characters of the concatenation of the strings should be
-   concerned.
-
-   If REGS is not NULL, and BUFP->no_sub is not set, the offsets of the match
-   and all groups is stored in REGS.  (For the "_2" variants, the offsets are
-   computed relative to the concatenation, not relative to the individual
-   strings.)
-
-   On success, re_match* functions return the length of the match, re_search*
-   return the position of the start of the match.  Return value -1 means no
-   match was found and -2 indicates an internal error.  */
-
-regoff_t
-re_match (bufp, string, length, start, regs)
-    struct re_pattern_buffer *bufp;
-    const char *string;
-    Idx length, start;
-    struct re_registers *regs;
-{
-  return re_search_stub (bufp, string, length, start, 0, length, regs, true);
-}
-#ifdef _LIBC
-weak_alias (__re_match, re_match)
-#endif
-
-regoff_t
-re_search (bufp, string, length, start, range, regs)
-    struct re_pattern_buffer *bufp;
-    const char *string;
-    Idx length, start;
-    regoff_t range;
-    struct re_registers *regs;
-{
-  return re_search_stub (bufp, string, length, start, range, length, regs,
-			 false);
-}
-#ifdef _LIBC
-weak_alias (__re_search, re_search)
-#endif
-
-regoff_t
-re_match_2 (bufp, string1, length1, string2, length2, start, regs, stop)
-    struct re_pattern_buffer *bufp;
-    const char *string1, *string2;
-    Idx length1, length2, start, stop;
-    struct re_registers *regs;
-{
-  return re_search_2_stub (bufp, string1, length1, string2, length2,
-			   start, 0, regs, stop, true);
-}
-#ifdef _LIBC
-weak_alias (__re_match_2, re_match_2)
-#endif
-
-regoff_t
-re_search_2 (bufp, string1, length1, string2, length2, start, range, regs, stop)
-    struct re_pattern_buffer *bufp;
-    const char *string1, *string2;
-    Idx length1, length2, start, stop;
-    regoff_t range;
-    struct re_registers *regs;
-{
-  return re_search_2_stub (bufp, string1, length1, string2, length2,
-			   start, range, regs, stop, false);
-}
-#ifdef _LIBC
-weak_alias (__re_search_2, re_search_2)
-#endif
-
-static regoff_t
-re_search_2_stub (struct re_pattern_buffer *bufp,
-		  const char *string1, Idx length1,
-		  const char *string2, Idx length2,
-		  Idx start, regoff_t range, struct re_registers *regs,
-		  Idx stop, bool ret_len)
-{
-  const char *str;
-  regoff_t rval;
-  Idx len = length1 + length2;
-  char *s = NULL;
-
-  if (BE (length1 < 0 || length2 < 0 || stop < 0 || len < length1, 0))
-    return -2;
-
-  /* Concatenate the strings.  */
-  if (length2 > 0)
-    if (length1 > 0)
-      {
-	s = re_malloc (char, len);
-
-	if (BE (s == NULL, 0))
-	  return -2;
-#ifdef _LIBC
-	memcpy (__mempcpy (s, string1, length1), string2, length2);
-#else
-	memcpy (s, string1, length1);
-	memcpy (s + length1, string2, length2);
-#endif
-	str = s;
-      }
-    else
-      str = string2;
-  else
-    str = string1;
-
-  rval = re_search_stub (bufp, str, len, start, range, stop, regs,
-			 ret_len);
-  re_free (s);
-  return rval;
-}
-
-/* The parameters have the same meaning as those of re_search.
-   Additional parameters:
-   If RET_LEN is true the length of the match is returned (re_match style);
-   otherwise the position of the match is returned.  */
-
-static regoff_t
-re_search_stub (struct re_pattern_buffer *bufp,
-		const char *string, Idx length,
-		Idx start, regoff_t range, Idx stop, struct re_registers *regs,
-		bool ret_len)
-{
-  reg_errcode_t result;
-  regmatch_t *pmatch;
-  Idx nregs;
-  regoff_t rval;
-  int eflags = 0;
-  re_dfa_t *dfa = bufp->buffer;
-  Idx last_start = start + range;
-
-  /* Check for out-of-range.  */
-  if (BE (start < 0 || start > length, 0))
-    return -1;
-  if (BE (length < last_start || (0 <= range && last_start < start), 0))
-    last_start = length;
-  else if (BE (last_start < 0 || (range < 0 && start <= last_start), 0))
-    last_start = 0;
-
-  lock_lock (dfa->lock);
-
-  eflags |= (bufp->not_bol) ? REG_NOTBOL : 0;
-  eflags |= (bufp->not_eol) ? REG_NOTEOL : 0;
-
-  /* Compile fastmap if we haven't yet.  */
-  if (start < last_start && bufp->fastmap != NULL && !bufp->fastmap_accurate)
-    re_compile_fastmap (bufp);
-
-  if (BE (bufp->no_sub, 0))
-    regs = NULL;
-
-  /* We need at least 1 register.  */
-  if (regs == NULL)
-    nregs = 1;
-  else if (BE (bufp->regs_allocated == REGS_FIXED
-	       && regs->num_regs <= bufp->re_nsub, 0))
-    {
-      nregs = regs->num_regs;
-      if (BE (nregs < 1, 0))
-	{
-	  /* Nothing can be copied to regs.  */
-	  regs = NULL;
-	  nregs = 1;
-	}
-    }
-  else
-    nregs = bufp->re_nsub + 1;
-  pmatch = re_malloc (regmatch_t, nregs);
-  if (BE (pmatch == NULL, 0))
-    {
-      rval = -2;
-      goto out;
-    }
-
-  result = re_search_internal (bufp, string, length, start, last_start, stop,
-			       nregs, pmatch, eflags);
-
-  rval = 0;
-
-  /* I hope we needn't fill their regs with -1's when no match was found.  */
-  if (result != REG_NOERROR)
-    rval = result == REG_NOMATCH ? -1 : -2;
-  else if (regs != NULL)
-    {
-      /* If caller wants register contents data back, copy them.  */
-      bufp->regs_allocated = re_copy_regs (regs, pmatch, nregs,
-					   bufp->regs_allocated);
-      if (BE (bufp->regs_allocated == REGS_UNALLOCATED, 0))
-	rval = -2;
-    }
-
-  if (BE (rval == 0, 1))
-    {
-      if (ret_len)
-	{
-	  assert (pmatch[0].rm_so == start);
-	  rval = pmatch[0].rm_eo - start;
-	}
-      else
-	rval = pmatch[0].rm_so;
-    }
-  re_free (pmatch);
- out:
-  lock_unlock (dfa->lock);
-  return rval;
-}
-
-static unsigned
-re_copy_regs (struct re_registers *regs, regmatch_t *pmatch, Idx nregs,
-	      int regs_allocated)
-{
-  int rval = REGS_REALLOCATE;
-  Idx i;
-  Idx need_regs = nregs + 1;
-  /* We need one extra element beyond 'num_regs' for the '-1' marker GNU code
-     uses.  */
-
-  /* Have the register data arrays been allocated?  */
-  if (regs_allocated == REGS_UNALLOCATED)
-    { /* No.  So allocate them with malloc.  */
-      regs->start = re_malloc (regoff_t, need_regs);
-      if (BE (regs->start == NULL, 0))
-	return REGS_UNALLOCATED;
-      regs->end = re_malloc (regoff_t, need_regs);
-      if (BE (regs->end == NULL, 0))
-	{
-	  re_free (regs->start);
-	  return REGS_UNALLOCATED;
-	}
-      regs->num_regs = need_regs;
-    }
-  else if (regs_allocated == REGS_REALLOCATE)
-    { /* Yes.  If we need more elements than were already
-	 allocated, reallocate them.  If we need fewer, just
-	 leave it alone.  */
-      if (BE (need_regs > regs->num_regs, 0))
-	{
-	  regoff_t *new_start = re_realloc (regs->start, regoff_t, need_regs);
-	  regoff_t *new_end;
-	  if (BE (new_start == NULL, 0))
-	    return REGS_UNALLOCATED;
-	  new_end = re_realloc (regs->end, regoff_t, need_regs);
-	  if (BE (new_end == NULL, 0))
-	    {
-	      re_free (new_start);
-	      return REGS_UNALLOCATED;
-	    }
-	  regs->start = new_start;
-	  regs->end = new_end;
-	  regs->num_regs = need_regs;
-	}
-    }
-  else
-    {
-      assert (regs_allocated == REGS_FIXED);
-      /* This function may not be called with REGS_FIXED and nregs too big.  */
-      assert (regs->num_regs >= nregs);
-      rval = REGS_FIXED;
-    }
-
-  /* Copy the regs.  */
-  for (i = 0; i < nregs; ++i)
-    {
-      regs->start[i] = pmatch[i].rm_so;
-      regs->end[i] = pmatch[i].rm_eo;
-    }
-  for ( ; i < regs->num_regs; ++i)
-    regs->start[i] = regs->end[i] = -1;
-
-  return rval;
-}
-
-/* Set REGS to hold NUM_REGS registers, storing them in STARTS and
-   ENDS.  Subsequent matches using PATTERN_BUFFER and REGS will use
-   this memory for recording register information.  STARTS and ENDS
-   must be allocated using the malloc library routine, and must each
-   be at least NUM_REGS * sizeof (regoff_t) bytes long.
-
-   If NUM_REGS == 0, then subsequent matches should allocate their own
-   register data.
-
-   Unless this function is called, the first search or match using
-   PATTERN_BUFFER will allocate its own register data, without
-   freeing the old data.  */
-
-void
-re_set_registers (bufp, regs, num_regs, starts, ends)
-    struct re_pattern_buffer *bufp;
-    struct re_registers *regs;
-    __re_size_t num_regs;
-    regoff_t *starts, *ends;
-{
-  if (num_regs)
-    {
-      bufp->regs_allocated = REGS_REALLOCATE;
-      regs->num_regs = num_regs;
-      regs->start = starts;
-      regs->end = ends;
-    }
-  else
-    {
-      bufp->regs_allocated = REGS_UNALLOCATED;
-      regs->num_regs = 0;
-      regs->start = regs->end = NULL;
-    }
-}
-#ifdef _LIBC
-weak_alias (__re_set_registers, re_set_registers)
-#endif
-
-/* Entry points compatible with 4.2 BSD regex library.  We don't define
-   them unless specifically requested.  */
-
-#if defined _REGEX_RE_COMP || defined _LIBC
-int
-# ifdef _LIBC
-weak_function
-# endif
-re_exec (s)
-     const char *s;
-{
-  return 0 == regexec (&re_comp_buf, s, 0, NULL, 0);
-}
-#endif /* _REGEX_RE_COMP */
-
-/* Internal entry point.  */
-
-/* Searches for a compiled pattern PREG in the string STRING, whose
-   length is LENGTH.  NMATCH, PMATCH, and EFLAGS have the same
-   meaning as with regexec.  LAST_START is START + RANGE, where
-   START and RANGE have the same meaning as with re_search.
-   Return REG_NOERROR if we find a match, and REG_NOMATCH if not,
-   otherwise return the error code.
-   Note: We assume front end functions already check ranges.
-   (0 <= LAST_START && LAST_START <= LENGTH)  */
-
-static reg_errcode_t
-__attribute_warn_unused_result__
-re_search_internal (const regex_t *preg,
-		    const char *string, Idx length,
-		    Idx start, Idx last_start, Idx stop,
-		    size_t nmatch, regmatch_t pmatch[],
-		    int eflags)
-{
-  reg_errcode_t err;
-  const re_dfa_t *dfa = preg->buffer;
-  Idx left_lim, right_lim;
-  int incr;
-  bool fl_longest_match;
-  int match_kind;
-  Idx match_first;
-  Idx match_last = REG_MISSING;
-  Idx extra_nmatch;
-  bool sb;
-  int ch;
-#if defined _LIBC || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)
-  re_match_context_t mctx = { .dfa = dfa };
-#else
-  re_match_context_t mctx;
-#endif
-  char *fastmap = ((preg->fastmap != NULL && preg->fastmap_accurate
-		    && start != last_start && !preg->can_be_null)
-		   ? preg->fastmap : NULL);
-  RE_TRANSLATE_TYPE t = preg->translate;
-
-#if !(defined _LIBC || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L))
-  memset (&mctx, '\0', sizeof (re_match_context_t));
-  mctx.dfa = dfa;
-#endif
-
-  extra_nmatch = (nmatch > preg->re_nsub) ? nmatch - (preg->re_nsub + 1) : 0;
-  nmatch -= extra_nmatch;
-
-  /* Check if the DFA haven't been compiled.  */
-  if (BE (preg->used == 0 || dfa->init_state == NULL
-	  || dfa->init_state_word == NULL || dfa->init_state_nl == NULL
-	  || dfa->init_state_begbuf == NULL, 0))
-    return REG_NOMATCH;
-
-#ifdef DEBUG
-  /* We assume front-end functions already check them.  */
-  assert (0 <= last_start && last_start <= length);
-#endif
-
-  /* If initial states with non-begbuf contexts have no elements,
-     the regex must be anchored.  If preg->newline_anchor is set,
-     we'll never use init_state_nl, so do not check it.  */
-  if (dfa->init_state->nodes.nelem == 0
-      && dfa->init_state_word->nodes.nelem == 0
-      && (dfa->init_state_nl->nodes.nelem == 0
-	  || !preg->newline_anchor))
-    {
-      if (start != 0 && last_start != 0)
-        return REG_NOMATCH;
-      start = last_start = 0;
-    }
-
-  /* We must check the longest matching, if nmatch > 0.  */
-  fl_longest_match = (nmatch != 0 || dfa->nbackref);
-
-  err = re_string_allocate (&mctx.input, string, length, dfa->nodes_len + 1,
-			    preg->translate, (preg->syntax & RE_ICASE) != 0,
-			    dfa);
-  if (BE (err != REG_NOERROR, 0))
-    goto free_return;
-  mctx.input.stop = stop;
-  mctx.input.raw_stop = stop;
-  mctx.input.newline_anchor = preg->newline_anchor;
-
-  err = match_ctx_init (&mctx, eflags, dfa->nbackref * 2);
-  if (BE (err != REG_NOERROR, 0))
-    goto free_return;
-
-  /* We will log all the DFA states through which the dfa pass,
-     if nmatch > 1, or this dfa has "multibyte node", which is a
-     back-reference or a node which can accept multibyte character or
-     multi character collating element.  */
-  if (nmatch > 1 || dfa->has_mb_node)
-    {
-      /* Avoid overflow.  */
-      if (BE ((MIN (IDX_MAX, SIZE_MAX / sizeof (re_dfastate_t *))
-               <= mctx.input.bufs_len), 0))
-	{
-	  err = REG_ESPACE;
-	  goto free_return;
-	}
-
-      mctx.state_log = re_malloc (re_dfastate_t *, mctx.input.bufs_len + 1);
-      if (BE (mctx.state_log == NULL, 0))
-	{
-	  err = REG_ESPACE;
-	  goto free_return;
-	}
-    }
-  else
-    mctx.state_log = NULL;
-
-  match_first = start;
-  mctx.input.tip_context = (eflags & REG_NOTBOL) ? CONTEXT_BEGBUF
-			   : CONTEXT_NEWLINE | CONTEXT_BEGBUF;
-
-  /* Check incrementally whether the input string matches.  */
-  incr = (last_start < start) ? -1 : 1;
-  left_lim = (last_start < start) ? last_start : start;
-  right_lim = (last_start < start) ? start : last_start;
-  sb = dfa->mb_cur_max == 1;
-  match_kind =
-    (fastmap
-     ? ((sb || !(preg->syntax & RE_ICASE || t) ? 4 : 0)
-	| (start <= last_start ? 2 : 0)
-	| (t != NULL ? 1 : 0))
-     : 8);
-
-  for (;; match_first += incr)
-    {
-      err = REG_NOMATCH;
-      if (match_first < left_lim || right_lim < match_first)
-	goto free_return;
-
-      /* Advance as rapidly as possible through the string, until we
-	 find a plausible place to start matching.  This may be done
-	 with varying efficiency, so there are various possibilities:
-	 only the most common of them are specialized, in order to
-	 save on code size.  We use a switch statement for speed.  */
-      switch (match_kind)
-	{
-	case 8:
-	  /* No fastmap.  */
-	  break;
-
-	case 7:
-	  /* Fastmap with single-byte translation, match forward.  */
-	  while (BE (match_first < right_lim, 1)
-		 && !fastmap[t[(unsigned char) string[match_first]]])
-	    ++match_first;
-	  goto forward_match_found_start_or_reached_end;
-
-	case 6:
-	  /* Fastmap without translation, match forward.  */
-	  while (BE (match_first < right_lim, 1)
-		 && !fastmap[(unsigned char) string[match_first]])
-	    ++match_first;
-
-	forward_match_found_start_or_reached_end:
-	  if (BE (match_first == right_lim, 0))
-	    {
-	      ch = match_first >= length
-		       ? 0 : (unsigned char) string[match_first];
-	      if (!fastmap[t ? t[ch] : ch])
-		goto free_return;
-	    }
-	  break;
-
-	case 4:
-	case 5:
-	  /* Fastmap without multi-byte translation, match backwards.  */
-	  while (match_first >= left_lim)
-	    {
-	      ch = match_first >= length
-		       ? 0 : (unsigned char) string[match_first];
-	      if (fastmap[t ? t[ch] : ch])
-		break;
-	      --match_first;
-	    }
-	  if (match_first < left_lim)
-	    goto free_return;
-	  break;
-
-	default:
-	  /* In this case, we can't determine easily the current byte,
-	     since it might be a component byte of a multibyte
-	     character.  Then we use the constructed buffer instead.  */
-	  for (;;)
-	    {
-	      /* If MATCH_FIRST is out of the valid range, reconstruct the
-		 buffers.  */
-	      __re_size_t offset = match_first - mctx.input.raw_mbs_idx;
-	      if (BE (offset >= (__re_size_t) mctx.input.valid_raw_len, 0))
-		{
-		  err = re_string_reconstruct (&mctx.input, match_first,
-					       eflags);
-		  if (BE (err != REG_NOERROR, 0))
-		    goto free_return;
-
-		  offset = match_first - mctx.input.raw_mbs_idx;
-		}
-	      /* If MATCH_FIRST is out of the buffer, leave it as '\0'.
-		 Note that MATCH_FIRST must not be smaller than 0.  */
-	      ch = (match_first >= length
-		    ? 0 : re_string_byte_at (&mctx.input, offset));
-	      if (fastmap[ch])
-		break;
-	      match_first += incr;
-	      if (match_first < left_lim || match_first > right_lim)
-		{
-		  err = REG_NOMATCH;
-		  goto free_return;
-		}
-	    }
-	  break;
-	}
-
-      /* Reconstruct the buffers so that the matcher can assume that
-	 the matching starts from the beginning of the buffer.  */
-      err = re_string_reconstruct (&mctx.input, match_first, eflags);
-      if (BE (err != REG_NOERROR, 0))
-	goto free_return;
-
-#ifdef RE_ENABLE_I18N
-     /* Don't consider this char as a possible match start if it part,
-	yet isn't the head, of a multibyte character.  */
-      if (!sb && !re_string_first_byte (&mctx.input, 0))
-	continue;
-#endif
-
-      /* It seems to be appropriate one, then use the matcher.  */
-      /* We assume that the matching starts from 0.  */
-      mctx.state_log_top = mctx.nbkref_ents = mctx.max_mb_elem_len = 0;
-      match_last = check_matching (&mctx, fl_longest_match,
-				   start <= last_start ? &match_first : NULL);
-      if (match_last != REG_MISSING)
-	{
-	  if (BE (match_last == REG_ERROR, 0))
-	    {
-	      err = REG_ESPACE;
-	      goto free_return;
-	    }
-	  else
-	    {
-	      mctx.match_last = match_last;
-	      if ((!preg->no_sub && nmatch > 1) || dfa->nbackref)
-		{
-		  re_dfastate_t *pstate = mctx.state_log[match_last];
-		  mctx.last_node = check_halt_state_context (&mctx, pstate,
-							     match_last);
-		}
-	      if ((!preg->no_sub && nmatch > 1 && dfa->has_plural_match)
-		  || dfa->nbackref)
-		{
-		  err = prune_impossible_nodes (&mctx);
-		  if (err == REG_NOERROR)
-		    break;
-		  if (BE (err != REG_NOMATCH, 0))
-		    goto free_return;
-		  match_last = REG_MISSING;
-		}
-	      else
-		break; /* We found a match.  */
-	    }
-	}
-
-      match_ctx_clean (&mctx);
-    }
-
-#ifdef DEBUG
-  assert (match_last != REG_MISSING);
-  assert (err == REG_NOERROR);
-#endif
-
-  /* Set pmatch[] if we need.  */
-  if (nmatch > 0)
-    {
-      Idx reg_idx;
-
-      /* Initialize registers.  */
-      for (reg_idx = 1; reg_idx < nmatch; ++reg_idx)
-	pmatch[reg_idx].rm_so = pmatch[reg_idx].rm_eo = -1;
-
-      /* Set the points where matching start/end.  */
-      pmatch[0].rm_so = 0;
-      pmatch[0].rm_eo = mctx.match_last;
-      /* FIXME: This function should fail if mctx.match_last exceeds
-	 the maximum possible regoff_t value.  We need a new error
-	 code REG_OVERFLOW.  */
-
-      if (!preg->no_sub && nmatch > 1)
-	{
-	  err = set_regs (preg, &mctx, nmatch, pmatch,
-			  dfa->has_plural_match && dfa->nbackref > 0);
-	  if (BE (err != REG_NOERROR, 0))
-	    goto free_return;
-	}
-
-      /* At last, add the offset to each register, since we slid
-	 the buffers so that we could assume that the matching starts
-	 from 0.  */
-      for (reg_idx = 0; reg_idx < nmatch; ++reg_idx)
-	if (pmatch[reg_idx].rm_so != -1)
-	  {
-#ifdef RE_ENABLE_I18N
-	    if (BE (mctx.input.offsets_needed != 0, 0))
-	      {
-		pmatch[reg_idx].rm_so =
-		  (pmatch[reg_idx].rm_so == mctx.input.valid_len
-		   ? mctx.input.valid_raw_len
-		   : mctx.input.offsets[pmatch[reg_idx].rm_so]);
-		pmatch[reg_idx].rm_eo =
-		  (pmatch[reg_idx].rm_eo == mctx.input.valid_len
-		   ? mctx.input.valid_raw_len
-		   : mctx.input.offsets[pmatch[reg_idx].rm_eo]);
-	      }
-#else
-	    assert (mctx.input.offsets_needed == 0);
-#endif
-	    pmatch[reg_idx].rm_so += match_first;
-	    pmatch[reg_idx].rm_eo += match_first;
-	  }
-      for (reg_idx = 0; reg_idx < extra_nmatch; ++reg_idx)
-	{
-	  pmatch[nmatch + reg_idx].rm_so = -1;
-	  pmatch[nmatch + reg_idx].rm_eo = -1;
-	}
-
-      if (dfa->subexp_map)
-	for (reg_idx = 0; reg_idx + 1 < nmatch; reg_idx++)
-	  if (dfa->subexp_map[reg_idx] != reg_idx)
-	    {
-	      pmatch[reg_idx + 1].rm_so
-		= pmatch[dfa->subexp_map[reg_idx] + 1].rm_so;
-	      pmatch[reg_idx + 1].rm_eo
-		= pmatch[dfa->subexp_map[reg_idx] + 1].rm_eo;
-	    }
-    }
-
- free_return:
-  re_free (mctx.state_log);
-  if (dfa->nbackref)
-    match_ctx_free (&mctx);
-  re_string_destruct (&mctx.input);
-  return err;
-}
-
-static reg_errcode_t
-__attribute_warn_unused_result__
-prune_impossible_nodes (re_match_context_t *mctx)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  Idx halt_node, match_last;
-  reg_errcode_t ret;
-  re_dfastate_t **sifted_states;
-  re_dfastate_t **lim_states = NULL;
-  re_sift_context_t sctx;
-#ifdef DEBUG
-  assert (mctx->state_log != NULL);
-#endif
-  match_last = mctx->match_last;
-  halt_node = mctx->last_node;
-
-  /* Avoid overflow.  */
-  if (BE (MIN (IDX_MAX, SIZE_MAX / sizeof (re_dfastate_t *)) <= match_last, 0))
-    return REG_ESPACE;
-
-  sifted_states = re_malloc (re_dfastate_t *, match_last + 1);
-  if (BE (sifted_states == NULL, 0))
-    {
-      ret = REG_ESPACE;
-      goto free_return;
-    }
-  if (dfa->nbackref)
-    {
-      lim_states = re_malloc (re_dfastate_t *, match_last + 1);
-      if (BE (lim_states == NULL, 0))
-	{
-	  ret = REG_ESPACE;
-	  goto free_return;
-	}
-      while (1)
-	{
-	  memset (lim_states, '\0',
-		  sizeof (re_dfastate_t *) * (match_last + 1));
-	  sift_ctx_init (&sctx, sifted_states, lim_states, halt_node,
-			 match_last);
-	  ret = sift_states_backward (mctx, &sctx);
-	  re_node_set_free (&sctx.limits);
-	  if (BE (ret != REG_NOERROR, 0))
-	      goto free_return;
-	  if (sifted_states[0] != NULL || lim_states[0] != NULL)
-	    break;
-	  do
-	    {
-	      --match_last;
-	      if (! REG_VALID_INDEX (match_last))
-		{
-		  ret = REG_NOMATCH;
-		  goto free_return;
-		}
-	    } while (mctx->state_log[match_last] == NULL
-		     || !mctx->state_log[match_last]->halt);
-	  halt_node = check_halt_state_context (mctx,
-						mctx->state_log[match_last],
-						match_last);
-	}
-      ret = merge_state_array (dfa, sifted_states, lim_states,
-			       match_last + 1);
-      re_free (lim_states);
-      lim_states = NULL;
-      if (BE (ret != REG_NOERROR, 0))
-	goto free_return;
-    }
-  else
-    {
-      sift_ctx_init (&sctx, sifted_states, lim_states, halt_node, match_last);
-      ret = sift_states_backward (mctx, &sctx);
-      re_node_set_free (&sctx.limits);
-      if (BE (ret != REG_NOERROR, 0))
-	goto free_return;
-      if (sifted_states[0] == NULL)
-	{
-	  ret = REG_NOMATCH;
-	  goto free_return;
-	}
-    }
-  re_free (mctx->state_log);
-  mctx->state_log = sifted_states;
-  sifted_states = NULL;
-  mctx->last_node = halt_node;
-  mctx->match_last = match_last;
-  ret = REG_NOERROR;
- free_return:
-  re_free (sifted_states);
-  re_free (lim_states);
-  return ret;
-}
-
-/* Acquire an initial state and return it.
-   We must select appropriate initial state depending on the context,
-   since initial states may have constraints like "\<", "^", etc..  */
-
-static inline re_dfastate_t *
-__attribute__ ((always_inline)) internal_function
-acquire_init_state_context (reg_errcode_t *err, const re_match_context_t *mctx,
-			    Idx idx)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  if (dfa->init_state->has_constraint)
-    {
-      unsigned int context;
-      context = re_string_context_at (&mctx->input, idx - 1, mctx->eflags);
-      if (IS_WORD_CONTEXT (context))
-	return dfa->init_state_word;
-      else if (IS_ORDINARY_CONTEXT (context))
-	return dfa->init_state;
-      else if (IS_BEGBUF_CONTEXT (context) && IS_NEWLINE_CONTEXT (context))
-	return dfa->init_state_begbuf;
-      else if (IS_NEWLINE_CONTEXT (context))
-	return dfa->init_state_nl;
-      else if (IS_BEGBUF_CONTEXT (context))
-	{
-	  /* It is relatively rare case, then calculate on demand.  */
-	  return re_acquire_state_context (err, dfa,
-					   dfa->init_state->entrance_nodes,
-					   context);
-	}
-      else
-	/* Must not happen?  */
-	return dfa->init_state;
-    }
-  else
-    return dfa->init_state;
-}
-
-/* Check whether the regular expression match input string INPUT or not,
-   and return the index where the matching end.  Return REG_MISSING if
-   there is no match, and return REG_ERROR in case of an error.
-   FL_LONGEST_MATCH means we want the POSIX longest matching.
-   If P_MATCH_FIRST is not NULL, and the match fails, it is set to the
-   next place where we may want to try matching.
-   Note that the matcher assumes that the matching starts from the current
-   index of the buffer.  */
-
-static Idx
-internal_function __attribute_warn_unused_result__
-check_matching (re_match_context_t *mctx, bool fl_longest_match,
-		Idx *p_match_first)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  reg_errcode_t err;
-  Idx match = 0;
-  Idx match_last = REG_MISSING;
-  Idx cur_str_idx = re_string_cur_idx (&mctx->input);
-  re_dfastate_t *cur_state;
-  bool at_init_state = p_match_first != NULL;
-  Idx next_start_idx = cur_str_idx;
-
-  err = REG_NOERROR;
-  cur_state = acquire_init_state_context (&err, mctx, cur_str_idx);
-  /* An initial state must not be NULL (invalid).  */
-  if (BE (cur_state == NULL, 0))
-    {
-      assert (err == REG_ESPACE);
-      return REG_ERROR;
-    }
-
-  if (mctx->state_log != NULL)
-    {
-      mctx->state_log[cur_str_idx] = cur_state;
-
-      /* Check OP_OPEN_SUBEXP in the initial state in case that we use them
-	 later.  E.g. Processing back references.  */
-      if (BE (dfa->nbackref, 0))
-	{
-	  at_init_state = false;
-	  err = check_subexp_matching_top (mctx, &cur_state->nodes, 0);
-	  if (BE (err != REG_NOERROR, 0))
-	    return err;
-
-	  if (cur_state->has_backref)
-	    {
-	      err = transit_state_bkref (mctx, &cur_state->nodes);
-	      if (BE (err != REG_NOERROR, 0))
-		return err;
-	    }
-	}
-    }
-
-  /* If the RE accepts NULL string.  */
-  if (BE (cur_state->halt, 0))
-    {
-      if (!cur_state->has_constraint
-	  || check_halt_state_context (mctx, cur_state, cur_str_idx))
-	{
-	  if (!fl_longest_match)
-	    return cur_str_idx;
-	  else
-	    {
-	      match_last = cur_str_idx;
-	      match = 1;
-	    }
-	}
-    }
-
-  while (!re_string_eoi (&mctx->input))
-    {
-      re_dfastate_t *old_state = cur_state;
-      Idx next_char_idx = re_string_cur_idx (&mctx->input) + 1;
-
-      if ((BE (next_char_idx >= mctx->input.bufs_len, 0)
-	   && mctx->input.bufs_len < mctx->input.len)
-	  || (BE (next_char_idx >= mctx->input.valid_len, 0)
-	      && mctx->input.valid_len < mctx->input.len))
-	{
-	  err = extend_buffers (mctx, next_char_idx + 1);
-	  if (BE (err != REG_NOERROR, 0))
-	    {
-	      assert (err == REG_ESPACE);
-	      return REG_ERROR;
-	    }
-	}
-
-      cur_state = transit_state (&err, mctx, cur_state);
-      if (mctx->state_log != NULL)
-	cur_state = merge_state_with_log (&err, mctx, cur_state);
-
-      if (cur_state == NULL)
-	{
-	  /* Reached the invalid state or an error.  Try to recover a valid
-	     state using the state log, if available and if we have not
-	     already found a valid (even if not the longest) match.  */
-	  if (BE (err != REG_NOERROR, 0))
-	    return REG_ERROR;
-
-	  if (mctx->state_log == NULL
-	      || (match && !fl_longest_match)
-	      || (cur_state = find_recover_state (&err, mctx)) == NULL)
-	    break;
-	}
-
-      if (BE (at_init_state, 0))
-	{
-	  if (old_state == cur_state)
-	    next_start_idx = next_char_idx;
-	  else
-	    at_init_state = false;
-	}
-
-      if (cur_state->halt)
-	{
-	  /* Reached a halt state.
-	     Check the halt state can satisfy the current context.  */
-	  if (!cur_state->has_constraint
-	      || check_halt_state_context (mctx, cur_state,
-					   re_string_cur_idx (&mctx->input)))
-	    {
-	      /* We found an appropriate halt state.  */
-	      match_last = re_string_cur_idx (&mctx->input);
-	      match = 1;
-
-	      /* We found a match, do not modify match_first below.  */
-	      p_match_first = NULL;
-	      if (!fl_longest_match)
-		break;
-	    }
-	}
-    }
-
-  if (p_match_first)
-    *p_match_first += next_start_idx;
-
-  return match_last;
-}
-
-/* Check NODE match the current context.  */
-
-static bool
-internal_function
-check_halt_node_context (const re_dfa_t *dfa, Idx node, unsigned int context)
-{
-  re_token_type_t type = dfa->nodes[node].type;
-  unsigned int constraint = dfa->nodes[node].constraint;
-  if (type != END_OF_RE)
-    return false;
-  if (!constraint)
-    return true;
-  if (NOT_SATISFY_NEXT_CONSTRAINT (constraint, context))
-    return false;
-  return true;
-}
-
-/* Check the halt state STATE match the current context.
-   Return 0 if not match, if the node, STATE has, is a halt node and
-   match the context, return the node.  */
-
-static Idx
-internal_function
-check_halt_state_context (const re_match_context_t *mctx,
-			  const re_dfastate_t *state, Idx idx)
-{
-  Idx i;
-  unsigned int context;
-#ifdef DEBUG
-  assert (state->halt);
-#endif
-  context = re_string_context_at (&mctx->input, idx, mctx->eflags);
-  for (i = 0; i < state->nodes.nelem; ++i)
-    if (check_halt_node_context (mctx->dfa, state->nodes.elems[i], context))
-      return state->nodes.elems[i];
-  return 0;
-}
-
-/* Compute the next node to which "NFA" transit from NODE("NFA" is a NFA
-   corresponding to the DFA).
-   Return the destination node, and update EPS_VIA_NODES;
-   return REG_MISSING in case of errors.  */
-
-static Idx
-internal_function
-proceed_next_node (const re_match_context_t *mctx, Idx nregs, regmatch_t *regs,
-		   Idx *pidx, Idx node, re_node_set *eps_via_nodes,
-		   struct re_fail_stack_t *fs)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  Idx i;
-  bool ok;
-  if (IS_EPSILON_NODE (dfa->nodes[node].type))
-    {
-      re_node_set *cur_nodes = &mctx->state_log[*pidx]->nodes;
-      re_node_set *edests = &dfa->edests[node];
-      Idx dest_node;
-      ok = re_node_set_insert (eps_via_nodes, node);
-      if (BE (! ok, 0))
-	return REG_ERROR;
-      /* Pick up a valid destination, or return REG_MISSING if none
-	 is found.  */
-      for (dest_node = REG_MISSING, i = 0; i < edests->nelem; ++i)
-	{
-	  Idx candidate = edests->elems[i];
-	  if (!re_node_set_contains (cur_nodes, candidate))
-	    continue;
-          if (dest_node == REG_MISSING)
-	    dest_node = candidate;
-
-	  else
-	    {
-	      /* In order to avoid infinite loop like "(a*)*", return the second
-		 epsilon-transition if the first was already considered.  */
-	      if (re_node_set_contains (eps_via_nodes, dest_node))
-		return candidate;
-
-	      /* Otherwise, push the second epsilon-transition on the fail stack.  */
-	      else if (fs != NULL
-		       && push_fail_stack (fs, *pidx, candidate, nregs, regs,
-					   eps_via_nodes))
-		return REG_ERROR;
-
-	      /* We know we are going to exit.  */
-	      break;
-	    }
-	}
-      return dest_node;
-    }
-  else
-    {
-      Idx naccepted = 0;
-      re_token_type_t type = dfa->nodes[node].type;
-
-#ifdef RE_ENABLE_I18N
-      if (dfa->nodes[node].accept_mb)
-	naccepted = check_node_accept_bytes (dfa, node, &mctx->input, *pidx);
-      else
-#endif /* RE_ENABLE_I18N */
-      if (type == OP_BACK_REF)
-	{
-	  Idx subexp_idx = dfa->nodes[node].opr.idx + 1;
-	  naccepted = regs[subexp_idx].rm_eo - regs[subexp_idx].rm_so;
-	  if (fs != NULL)
-	    {
-	      if (regs[subexp_idx].rm_so == -1 || regs[subexp_idx].rm_eo == -1)
-		return REG_MISSING;
-	      else if (naccepted)
-		{
-		  char *buf = (char *) re_string_get_buffer (&mctx->input);
-		  if (memcmp (buf + regs[subexp_idx].rm_so, buf + *pidx,
-			      naccepted) != 0)
-		    return REG_MISSING;
-		}
-	    }
-
-	  if (naccepted == 0)
-	    {
-	      Idx dest_node;
-	      ok = re_node_set_insert (eps_via_nodes, node);
-	      if (BE (! ok, 0))
-		return REG_ERROR;
-	      dest_node = dfa->edests[node].elems[0];
-	      if (re_node_set_contains (&mctx->state_log[*pidx]->nodes,
-					dest_node))
-		return dest_node;
-	    }
-	}
-
-      if (naccepted != 0
-	  || check_node_accept (mctx, dfa->nodes + node, *pidx))
-	{
-	  Idx dest_node = dfa->nexts[node];
-	  *pidx = (naccepted == 0) ? *pidx + 1 : *pidx + naccepted;
-	  if (fs && (*pidx > mctx->match_last || mctx->state_log[*pidx] == NULL
-		     || !re_node_set_contains (&mctx->state_log[*pidx]->nodes,
-					       dest_node)))
-	    return REG_MISSING;
-	  re_node_set_empty (eps_via_nodes);
-	  return dest_node;
-	}
-    }
-  return REG_MISSING;
-}
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-push_fail_stack (struct re_fail_stack_t *fs, Idx str_idx, Idx dest_node,
-		 Idx nregs, regmatch_t *regs, re_node_set *eps_via_nodes)
-{
-  reg_errcode_t err;
-  Idx num = fs->num++;
-  if (fs->num == fs->alloc)
-    {
-      struct re_fail_stack_ent_t *new_array;
-      new_array = realloc (fs->stack, (sizeof (struct re_fail_stack_ent_t)
-				       * fs->alloc * 2));
-      if (new_array == NULL)
-	return REG_ESPACE;
-      fs->alloc *= 2;
-      fs->stack = new_array;
-    }
-  fs->stack[num].idx = str_idx;
-  fs->stack[num].node = dest_node;
-  fs->stack[num].regs = re_malloc (regmatch_t, nregs);
-  if (fs->stack[num].regs == NULL)
-    return REG_ESPACE;
-  memcpy (fs->stack[num].regs, regs, sizeof (regmatch_t) * nregs);
-  err = re_node_set_init_copy (&fs->stack[num].eps_via_nodes, eps_via_nodes);
-  return err;
-}
-
-static Idx
-internal_function
-pop_fail_stack (struct re_fail_stack_t *fs, Idx *pidx, Idx nregs,
-		regmatch_t *regs, re_node_set *eps_via_nodes)
-{
-  Idx num = --fs->num;
-  assert (REG_VALID_INDEX (num));
-  *pidx = fs->stack[num].idx;
-  memcpy (regs, fs->stack[num].regs, sizeof (regmatch_t) * nregs);
-  re_node_set_free (eps_via_nodes);
-  re_free (fs->stack[num].regs);
-  *eps_via_nodes = fs->stack[num].eps_via_nodes;
-  return fs->stack[num].node;
-}
-
-/* Set the positions where the subexpressions are starts/ends to registers
-   PMATCH.
-   Note: We assume that pmatch[0] is already set, and
-   pmatch[i].rm_so == pmatch[i].rm_eo == -1 for 0 < i < nmatch.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-set_regs (const regex_t *preg, const re_match_context_t *mctx, size_t nmatch,
-	  regmatch_t *pmatch, bool fl_backtrack)
-{
-  const re_dfa_t *dfa = preg->buffer;
-  Idx idx, cur_node;
-  re_node_set eps_via_nodes;
-  struct re_fail_stack_t *fs;
-  struct re_fail_stack_t fs_body = { 0, 2, NULL };
-  regmatch_t *prev_idx_match;
-  bool prev_idx_match_malloced = false;
-
-#ifdef DEBUG
-  assert (nmatch > 1);
-  assert (mctx->state_log != NULL);
-#endif
-  if (fl_backtrack)
-    {
-      fs = &fs_body;
-      fs->stack = re_malloc (struct re_fail_stack_ent_t, fs->alloc);
-      if (fs->stack == NULL)
-	return REG_ESPACE;
-    }
-  else
-    fs = NULL;
-
-  cur_node = dfa->init_node;
-  re_node_set_init_empty (&eps_via_nodes);
-
-  if (__libc_use_alloca (nmatch * sizeof (regmatch_t)))
-    prev_idx_match = (regmatch_t *) alloca (nmatch * sizeof (regmatch_t));
-  else
-    {
-      prev_idx_match = re_malloc (regmatch_t, nmatch);
-      if (prev_idx_match == NULL)
-	{
-	  free_fail_stack_return (fs);
-	  return REG_ESPACE;
-	}
-      prev_idx_match_malloced = true;
-    }
-  memcpy (prev_idx_match, pmatch, sizeof (regmatch_t) * nmatch);
-
-  for (idx = pmatch[0].rm_so; idx <= pmatch[0].rm_eo ;)
-    {
-      update_regs (dfa, pmatch, prev_idx_match, cur_node, idx, nmatch);
-
-      if (idx == pmatch[0].rm_eo && cur_node == mctx->last_node)
-	{
-	  Idx reg_idx;
-	  if (fs)
-	    {
-	      for (reg_idx = 0; reg_idx < nmatch; ++reg_idx)
-		if (pmatch[reg_idx].rm_so > -1 && pmatch[reg_idx].rm_eo == -1)
-		  break;
-	      if (reg_idx == nmatch)
-		{
-		  re_node_set_free (&eps_via_nodes);
-		  if (prev_idx_match_malloced)
-		    re_free (prev_idx_match);
-		  return free_fail_stack_return (fs);
-		}
-	      cur_node = pop_fail_stack (fs, &idx, nmatch, pmatch,
-					 &eps_via_nodes);
-	    }
-	  else
-	    {
-	      re_node_set_free (&eps_via_nodes);
-	      if (prev_idx_match_malloced)
-		re_free (prev_idx_match);
-	      return REG_NOERROR;
-	    }
-	}
-
-      /* Proceed to next node.  */
-      cur_node = proceed_next_node (mctx, nmatch, pmatch, &idx, cur_node,
-				    &eps_via_nodes, fs);
-
-      if (BE (! REG_VALID_INDEX (cur_node), 0))
-	{
-	  if (BE (cur_node == REG_ERROR, 0))
-	    {
-	      re_node_set_free (&eps_via_nodes);
-	      if (prev_idx_match_malloced)
-		re_free (prev_idx_match);
-	      free_fail_stack_return (fs);
-	      return REG_ESPACE;
-	    }
-	  if (fs)
-	    cur_node = pop_fail_stack (fs, &idx, nmatch, pmatch,
-				       &eps_via_nodes);
-	  else
-	    {
-	      re_node_set_free (&eps_via_nodes);
-	      if (prev_idx_match_malloced)
-		re_free (prev_idx_match);
-	      return REG_NOMATCH;
-	    }
-	}
-    }
-  re_node_set_free (&eps_via_nodes);
-  if (prev_idx_match_malloced)
-    re_free (prev_idx_match);
-  return free_fail_stack_return (fs);
-}
-
-static reg_errcode_t
-internal_function
-free_fail_stack_return (struct re_fail_stack_t *fs)
-{
-  if (fs)
-    {
-      Idx fs_idx;
-      for (fs_idx = 0; fs_idx < fs->num; ++fs_idx)
-	{
-	  re_node_set_free (&fs->stack[fs_idx].eps_via_nodes);
-	  re_free (fs->stack[fs_idx].regs);
-	}
-      re_free (fs->stack);
-    }
-  return REG_NOERROR;
-}
-
-static void
-internal_function
-update_regs (const re_dfa_t *dfa, regmatch_t *pmatch,
-	     regmatch_t *prev_idx_match, Idx cur_node, Idx cur_idx, Idx nmatch)
-{
-  int type = dfa->nodes[cur_node].type;
-  if (type == OP_OPEN_SUBEXP)
-    {
-      Idx reg_num = dfa->nodes[cur_node].opr.idx + 1;
-
-      /* We are at the first node of this sub expression.  */
-      if (reg_num < nmatch)
-	{
-	  pmatch[reg_num].rm_so = cur_idx;
-	  pmatch[reg_num].rm_eo = -1;
-	}
-    }
-  else if (type == OP_CLOSE_SUBEXP)
-    {
-      Idx reg_num = dfa->nodes[cur_node].opr.idx + 1;
-      if (reg_num < nmatch)
-	{
-	  /* We are at the last node of this sub expression.  */
-	  if (pmatch[reg_num].rm_so < cur_idx)
-	    {
-	      pmatch[reg_num].rm_eo = cur_idx;
-	      /* This is a non-empty match or we are not inside an optional
-		 subexpression.  Accept this right away.  */
-	      memcpy (prev_idx_match, pmatch, sizeof (regmatch_t) * nmatch);
-	    }
-	  else
-	    {
-	      if (dfa->nodes[cur_node].opt_subexp
-		  && prev_idx_match[reg_num].rm_so != -1)
-		/* We transited through an empty match for an optional
-		   subexpression, like (a?)*, and this is not the subexp's
-		   first match.  Copy back the old content of the registers
-		   so that matches of an inner subexpression are undone as
-		   well, like in ((a?))*.  */
-		memcpy (pmatch, prev_idx_match, sizeof (regmatch_t) * nmatch);
-	      else
-		/* We completed a subexpression, but it may be part of
-		   an optional one, so do not update PREV_IDX_MATCH.  */
-		pmatch[reg_num].rm_eo = cur_idx;
-	    }
-	}
-    }
-}
-
-/* This function checks the STATE_LOG from the SCTX->last_str_idx to 0
-   and sift the nodes in each states according to the following rules.
-   Updated state_log will be wrote to STATE_LOG.
-
-   Rules: We throw away the Node 'a' in the STATE_LOG[STR_IDX] if...
-     1. When STR_IDX == MATCH_LAST(the last index in the state_log):
-	If 'a' isn't the LAST_NODE and 'a' can't epsilon transit to
-	the LAST_NODE, we throw away the node 'a'.
-     2. When 0 <= STR_IDX < MATCH_LAST and 'a' accepts
-	string 's' and transit to 'b':
-	i. If 'b' isn't in the STATE_LOG[STR_IDX+strlen('s')], we throw
-	   away the node 'a'.
-	ii. If 'b' is in the STATE_LOG[STR_IDX+strlen('s')] but 'b' is
-	    thrown away, we throw away the node 'a'.
-     3. When 0 <= STR_IDX < MATCH_LAST and 'a' epsilon transit to 'b':
-	i. If 'b' isn't in the STATE_LOG[STR_IDX], we throw away the
-	   node 'a'.
-	ii. If 'b' is in the STATE_LOG[STR_IDX] but 'b' is thrown away,
-	    we throw away the node 'a'.  */
-
-#define STATE_NODE_CONTAINS(state,node) \
-  ((state) != NULL && re_node_set_contains (&(state)->nodes, node))
-
-static reg_errcode_t
-internal_function
-sift_states_backward (const re_match_context_t *mctx, re_sift_context_t *sctx)
-{
-  reg_errcode_t err;
-  int null_cnt = 0;
-  Idx str_idx = sctx->last_str_idx;
-  re_node_set cur_dest;
-
-#ifdef DEBUG
-  assert (mctx->state_log != NULL && mctx->state_log[str_idx] != NULL);
-#endif
-
-  /* Build sifted state_log[str_idx].  It has the nodes which can epsilon
-     transit to the last_node and the last_node itself.  */
-  err = re_node_set_init_1 (&cur_dest, sctx->last_node);
-  if (BE (err != REG_NOERROR, 0))
-    return err;
-  err = update_cur_sifted_state (mctx, sctx, str_idx, &cur_dest);
-  if (BE (err != REG_NOERROR, 0))
-    goto free_return;
-
-  /* Then check each states in the state_log.  */
-  while (str_idx > 0)
-    {
-      /* Update counters.  */
-      null_cnt = (sctx->sifted_states[str_idx] == NULL) ? null_cnt + 1 : 0;
-      if (null_cnt > mctx->max_mb_elem_len)
-	{
-	  memset (sctx->sifted_states, '\0',
-		  sizeof (re_dfastate_t *) * str_idx);
-	  re_node_set_free (&cur_dest);
-	  return REG_NOERROR;
-	}
-      re_node_set_empty (&cur_dest);
-      --str_idx;
-
-      if (mctx->state_log[str_idx])
-	{
-	  err = build_sifted_states (mctx, sctx, str_idx, &cur_dest);
-	  if (BE (err != REG_NOERROR, 0))
-	    goto free_return;
-	}
-
-      /* Add all the nodes which satisfy the following conditions:
-	 - It can epsilon transit to a node in CUR_DEST.
-	 - It is in CUR_SRC.
-	 And update state_log.  */
-      err = update_cur_sifted_state (mctx, sctx, str_idx, &cur_dest);
-      if (BE (err != REG_NOERROR, 0))
-	goto free_return;
-    }
-  err = REG_NOERROR;
- free_return:
-  re_node_set_free (&cur_dest);
-  return err;
-}
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-build_sifted_states (const re_match_context_t *mctx, re_sift_context_t *sctx,
-		     Idx str_idx, re_node_set *cur_dest)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  const re_node_set *cur_src = &mctx->state_log[str_idx]->non_eps_nodes;
-  Idx i;
-
-  /* Then build the next sifted state.
-     We build the next sifted state on 'cur_dest', and update
-     'sifted_states[str_idx]' with 'cur_dest'.
-     Note:
-     'cur_dest' is the sifted state from 'state_log[str_idx + 1]'.
-     'cur_src' points the node_set of the old 'state_log[str_idx]'
-     (with the epsilon nodes pre-filtered out).  */
-  for (i = 0; i < cur_src->nelem; i++)
-    {
-      Idx prev_node = cur_src->elems[i];
-      int naccepted = 0;
-      bool ok;
-
-#ifdef DEBUG
-      re_token_type_t type = dfa->nodes[prev_node].type;
-      assert (!IS_EPSILON_NODE (type));
-#endif
-#ifdef RE_ENABLE_I18N
-      /* If the node may accept "multi byte".  */
-      if (dfa->nodes[prev_node].accept_mb)
-	naccepted = sift_states_iter_mb (mctx, sctx, prev_node,
-					 str_idx, sctx->last_str_idx);
-#endif /* RE_ENABLE_I18N */
-
-      /* We don't check backreferences here.
-	 See update_cur_sifted_state().  */
-      if (!naccepted
-	  && check_node_accept (mctx, dfa->nodes + prev_node, str_idx)
-	  && STATE_NODE_CONTAINS (sctx->sifted_states[str_idx + 1],
-				  dfa->nexts[prev_node]))
-	naccepted = 1;
-
-      if (naccepted == 0)
-	continue;
-
-      if (sctx->limits.nelem)
-	{
-	  Idx to_idx = str_idx + naccepted;
-	  if (check_dst_limits (mctx, &sctx->limits,
-				dfa->nexts[prev_node], to_idx,
-				prev_node, str_idx))
-	    continue;
-	}
-      ok = re_node_set_insert (cur_dest, prev_node);
-      if (BE (! ok, 0))
-	return REG_ESPACE;
-    }
-
-  return REG_NOERROR;
-}
-
-/* Helper functions.  */
-
-static reg_errcode_t
-internal_function
-clean_state_log_if_needed (re_match_context_t *mctx, Idx next_state_log_idx)
-{
-  Idx top = mctx->state_log_top;
-
-  if ((next_state_log_idx >= mctx->input.bufs_len
-       && mctx->input.bufs_len < mctx->input.len)
-      || (next_state_log_idx >= mctx->input.valid_len
-	  && mctx->input.valid_len < mctx->input.len))
-    {
-      reg_errcode_t err;
-      err = extend_buffers (mctx, next_state_log_idx + 1);
-      if (BE (err != REG_NOERROR, 0))
-	return err;
-    }
-
-  if (top < next_state_log_idx)
-    {
-      memset (mctx->state_log + top + 1, '\0',
-	      sizeof (re_dfastate_t *) * (next_state_log_idx - top));
-      mctx->state_log_top = next_state_log_idx;
-    }
-  return REG_NOERROR;
-}
-
-static reg_errcode_t
-internal_function
-merge_state_array (const re_dfa_t *dfa, re_dfastate_t **dst,
-		   re_dfastate_t **src, Idx num)
-{
-  Idx st_idx;
-  reg_errcode_t err;
-  for (st_idx = 0; st_idx < num; ++st_idx)
-    {
-      if (dst[st_idx] == NULL)
-	dst[st_idx] = src[st_idx];
-      else if (src[st_idx] != NULL)
-	{
-	  re_node_set merged_set;
-	  err = re_node_set_init_union (&merged_set, &dst[st_idx]->nodes,
-					&src[st_idx]->nodes);
-	  if (BE (err != REG_NOERROR, 0))
-	    return err;
-	  dst[st_idx] = re_acquire_state (&err, dfa, &merged_set);
-	  re_node_set_free (&merged_set);
-	  if (BE (err != REG_NOERROR, 0))
-	    return err;
-	}
-    }
-  return REG_NOERROR;
-}
-
-static reg_errcode_t
-internal_function
-update_cur_sifted_state (const re_match_context_t *mctx,
-			 re_sift_context_t *sctx, Idx str_idx,
-			 re_node_set *dest_nodes)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  reg_errcode_t err = REG_NOERROR;
-  const re_node_set *candidates;
-  candidates = ((mctx->state_log[str_idx] == NULL) ? NULL
-		: &mctx->state_log[str_idx]->nodes);
-
-  if (dest_nodes->nelem == 0)
-    sctx->sifted_states[str_idx] = NULL;
-  else
-    {
-      if (candidates)
-	{
-	  /* At first, add the nodes which can epsilon transit to a node in
-	     DEST_NODE.  */
-	  err = add_epsilon_src_nodes (dfa, dest_nodes, candidates);
-	  if (BE (err != REG_NOERROR, 0))
-	    return err;
-
-	  /* Then, check the limitations in the current sift_context.  */
-	  if (sctx->limits.nelem)
-	    {
-	      err = check_subexp_limits (dfa, dest_nodes, candidates, &sctx->limits,
-					 mctx->bkref_ents, str_idx);
-	      if (BE (err != REG_NOERROR, 0))
-		return err;
-	    }
-	}
-
-      sctx->sifted_states[str_idx] = re_acquire_state (&err, dfa, dest_nodes);
-      if (BE (err != REG_NOERROR, 0))
-	return err;
-    }
-
-  if (candidates && mctx->state_log[str_idx]->has_backref)
-    {
-      err = sift_states_bkref (mctx, sctx, str_idx, candidates);
-      if (BE (err != REG_NOERROR, 0))
-	return err;
-    }
-  return REG_NOERROR;
-}
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-add_epsilon_src_nodes (const re_dfa_t *dfa, re_node_set *dest_nodes,
-		       const re_node_set *candidates)
-{
-  reg_errcode_t err = REG_NOERROR;
-  Idx i;
-
-  re_dfastate_t *state = re_acquire_state (&err, dfa, dest_nodes);
-  if (BE (err != REG_NOERROR, 0))
-    return err;
-
-  if (!state->inveclosure.alloc)
-    {
-      err = re_node_set_alloc (&state->inveclosure, dest_nodes->nelem);
-      if (BE (err != REG_NOERROR, 0))
-	return REG_ESPACE;
-      for (i = 0; i < dest_nodes->nelem; i++)
-	{
-	  err = re_node_set_merge (&state->inveclosure,
-				   dfa->inveclosures + dest_nodes->elems[i]);
-	  if (BE (err != REG_NOERROR, 0))
-	    return REG_ESPACE;
-	}
-    }
-  return re_node_set_add_intersect (dest_nodes, candidates,
-				    &state->inveclosure);
-}
-
-static reg_errcode_t
-internal_function
-sub_epsilon_src_nodes (const re_dfa_t *dfa, Idx node, re_node_set *dest_nodes,
-		       const re_node_set *candidates)
-{
-    Idx ecl_idx;
-    reg_errcode_t err;
-    re_node_set *inv_eclosure = dfa->inveclosures + node;
-    re_node_set except_nodes;
-    re_node_set_init_empty (&except_nodes);
-    for (ecl_idx = 0; ecl_idx < inv_eclosure->nelem; ++ecl_idx)
-      {
-	Idx cur_node = inv_eclosure->elems[ecl_idx];
-	if (cur_node == node)
-	  continue;
-	if (IS_EPSILON_NODE (dfa->nodes[cur_node].type))
-	  {
-	    Idx edst1 = dfa->edests[cur_node].elems[0];
-	    Idx edst2 = ((dfa->edests[cur_node].nelem > 1)
-			 ? dfa->edests[cur_node].elems[1] : REG_MISSING);
-	    if ((!re_node_set_contains (inv_eclosure, edst1)
-		 && re_node_set_contains (dest_nodes, edst1))
-		|| (REG_VALID_NONZERO_INDEX (edst2)
-		    && !re_node_set_contains (inv_eclosure, edst2)
-		    && re_node_set_contains (dest_nodes, edst2)))
-	      {
-		err = re_node_set_add_intersect (&except_nodes, candidates,
-						 dfa->inveclosures + cur_node);
-		if (BE (err != REG_NOERROR, 0))
-		  {
-		    re_node_set_free (&except_nodes);
-		    return err;
-		  }
-	      }
-	  }
-      }
-    for (ecl_idx = 0; ecl_idx < inv_eclosure->nelem; ++ecl_idx)
-      {
-	Idx cur_node = inv_eclosure->elems[ecl_idx];
-	if (!re_node_set_contains (&except_nodes, cur_node))
-	  {
-	    Idx idx = re_node_set_contains (dest_nodes, cur_node) - 1;
-	    re_node_set_remove_at (dest_nodes, idx);
-	  }
-      }
-    re_node_set_free (&except_nodes);
-    return REG_NOERROR;
-}
-
-static bool
-internal_function
-check_dst_limits (const re_match_context_t *mctx, const re_node_set *limits,
-		  Idx dst_node, Idx dst_idx, Idx src_node, Idx src_idx)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  Idx lim_idx, src_pos, dst_pos;
-
-  Idx dst_bkref_idx = search_cur_bkref_entry (mctx, dst_idx);
-  Idx src_bkref_idx = search_cur_bkref_entry (mctx, src_idx);
-  for (lim_idx = 0; lim_idx < limits->nelem; ++lim_idx)
-    {
-      Idx subexp_idx;
-      struct re_backref_cache_entry *ent;
-      ent = mctx->bkref_ents + limits->elems[lim_idx];
-      subexp_idx = dfa->nodes[ent->node].opr.idx;
-
-      dst_pos = check_dst_limits_calc_pos (mctx, limits->elems[lim_idx],
-					   subexp_idx, dst_node, dst_idx,
-					   dst_bkref_idx);
-      src_pos = check_dst_limits_calc_pos (mctx, limits->elems[lim_idx],
-					   subexp_idx, src_node, src_idx,
-					   src_bkref_idx);
-
-      /* In case of:
-	 <src> <dst> ( <subexp> )
-	 ( <subexp> ) <src> <dst>
-	 ( <subexp1> <src> <subexp2> <dst> <subexp3> )  */
-      if (src_pos == dst_pos)
-	continue; /* This is unrelated limitation.  */
-      else
-	return true;
-    }
-  return false;
-}
-
-static int
-internal_function
-check_dst_limits_calc_pos_1 (const re_match_context_t *mctx, int boundaries,
-			     Idx subexp_idx, Idx from_node, Idx bkref_idx)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  const re_node_set *eclosures = dfa->eclosures + from_node;
-  Idx node_idx;
-
-  /* Else, we are on the boundary: examine the nodes on the epsilon
-     closure.  */
-  for (node_idx = 0; node_idx < eclosures->nelem; ++node_idx)
-    {
-      Idx node = eclosures->elems[node_idx];
-      switch (dfa->nodes[node].type)
-	{
-	case OP_BACK_REF:
-	  if (bkref_idx != REG_MISSING)
-	    {
-	      struct re_backref_cache_entry *ent = mctx->bkref_ents + bkref_idx;
-	      do
-		{
-		  Idx dst;
-		  int cpos;
-
-		  if (ent->node != node)
-		    continue;
-
-		  if (subexp_idx < BITSET_WORD_BITS
-		      && !(ent->eps_reachable_subexps_map
-			   & ((bitset_word_t) 1 << subexp_idx)))
-		    continue;
-
-		  /* Recurse trying to reach the OP_OPEN_SUBEXP and
-		     OP_CLOSE_SUBEXP cases below.  But, if the
-		     destination node is the same node as the source
-		     node, don't recurse because it would cause an
-		     infinite loop: a regex that exhibits this behavior
-		     is ()\1*\1*  */
-		  dst = dfa->edests[node].elems[0];
-		  if (dst == from_node)
-		    {
-		      if (boundaries & 1)
-			return -1;
-		      else /* if (boundaries & 2) */
-			return 0;
-		    }
-
-		  cpos =
-		    check_dst_limits_calc_pos_1 (mctx, boundaries, subexp_idx,
-						 dst, bkref_idx);
-		  if (cpos == -1 /* && (boundaries & 1) */)
-		    return -1;
-		  if (cpos == 0 && (boundaries & 2))
-		    return 0;
-
-		  if (subexp_idx < BITSET_WORD_BITS)
-		    ent->eps_reachable_subexps_map
-		      &= ~((bitset_word_t) 1 << subexp_idx);
-		}
-	      while (ent++->more);
-	    }
-	  break;
-
-	case OP_OPEN_SUBEXP:
-	  if ((boundaries & 1) && subexp_idx == dfa->nodes[node].opr.idx)
-	    return -1;
-	  break;
-
-	case OP_CLOSE_SUBEXP:
-	  if ((boundaries & 2) && subexp_idx == dfa->nodes[node].opr.idx)
-	    return 0;
-	  break;
-
-	default:
-	    break;
-	}
-    }
-
-  return (boundaries & 2) ? 1 : 0;
-}
-
-static int
-internal_function
-check_dst_limits_calc_pos (const re_match_context_t *mctx, Idx limit,
-			   Idx subexp_idx, Idx from_node, Idx str_idx,
-			   Idx bkref_idx)
-{
-  struct re_backref_cache_entry *lim = mctx->bkref_ents + limit;
-  int boundaries;
-
-  /* If we are outside the range of the subexpression, return -1 or 1.  */
-  if (str_idx < lim->subexp_from)
-    return -1;
-
-  if (lim->subexp_to < str_idx)
-    return 1;
-
-  /* If we are within the subexpression, return 0.  */
-  boundaries = (str_idx == lim->subexp_from);
-  boundaries |= (str_idx == lim->subexp_to) << 1;
-  if (boundaries == 0)
-    return 0;
-
-  /* Else, examine epsilon closure.  */
-  return check_dst_limits_calc_pos_1 (mctx, boundaries, subexp_idx,
-				      from_node, bkref_idx);
-}
-
-/* Check the limitations of sub expressions LIMITS, and remove the nodes
-   which are against limitations from DEST_NODES. */
-
-static reg_errcode_t
-internal_function
-check_subexp_limits (const re_dfa_t *dfa, re_node_set *dest_nodes,
-		     const re_node_set *candidates, re_node_set *limits,
-		     struct re_backref_cache_entry *bkref_ents, Idx str_idx)
-{
-  reg_errcode_t err;
-  Idx node_idx, lim_idx;
-
-  for (lim_idx = 0; lim_idx < limits->nelem; ++lim_idx)
-    {
-      Idx subexp_idx;
-      struct re_backref_cache_entry *ent;
-      ent = bkref_ents + limits->elems[lim_idx];
-
-      if (str_idx <= ent->subexp_from || ent->str_idx < str_idx)
-	continue; /* This is unrelated limitation.  */
-
-      subexp_idx = dfa->nodes[ent->node].opr.idx;
-      if (ent->subexp_to == str_idx)
-	{
-	  Idx ops_node = REG_MISSING;
-	  Idx cls_node = REG_MISSING;
-	  for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx)
-	    {
-	      Idx node = dest_nodes->elems[node_idx];
-	      re_token_type_t type = dfa->nodes[node].type;
-	      if (type == OP_OPEN_SUBEXP
-		  && subexp_idx == dfa->nodes[node].opr.idx)
-		ops_node = node;
-	      else if (type == OP_CLOSE_SUBEXP
-		       && subexp_idx == dfa->nodes[node].opr.idx)
-		cls_node = node;
-	    }
-
-	  /* Check the limitation of the open subexpression.  */
-	  /* Note that (ent->subexp_to = str_idx != ent->subexp_from).  */
-	  if (REG_VALID_INDEX (ops_node))
-	    {
-	      err = sub_epsilon_src_nodes (dfa, ops_node, dest_nodes,
-					   candidates);
-	      if (BE (err != REG_NOERROR, 0))
-		return err;
-	    }
-
-	  /* Check the limitation of the close subexpression.  */
-	  if (REG_VALID_INDEX (cls_node))
-	    for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx)
-	      {
-		Idx node = dest_nodes->elems[node_idx];
-		if (!re_node_set_contains (dfa->inveclosures + node,
-					   cls_node)
-		    && !re_node_set_contains (dfa->eclosures + node,
-					      cls_node))
-		  {
-		    /* It is against this limitation.
-		       Remove it form the current sifted state.  */
-		    err = sub_epsilon_src_nodes (dfa, node, dest_nodes,
-						 candidates);
-		    if (BE (err != REG_NOERROR, 0))
-		      return err;
-		    --node_idx;
-		  }
-	      }
-	}
-      else /* (ent->subexp_to != str_idx)  */
-	{
-	  for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx)
-	    {
-	      Idx node = dest_nodes->elems[node_idx];
-	      re_token_type_t type = dfa->nodes[node].type;
-	      if (type == OP_CLOSE_SUBEXP || type == OP_OPEN_SUBEXP)
-		{
-		  if (subexp_idx != dfa->nodes[node].opr.idx)
-		    continue;
-		  /* It is against this limitation.
-		     Remove it form the current sifted state.  */
-		  err = sub_epsilon_src_nodes (dfa, node, dest_nodes,
-					       candidates);
-		  if (BE (err != REG_NOERROR, 0))
-		    return err;
-		}
-	    }
-	}
-    }
-  return REG_NOERROR;
-}
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-sift_states_bkref (const re_match_context_t *mctx, re_sift_context_t *sctx,
-		   Idx str_idx, const re_node_set *candidates)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  reg_errcode_t err;
-  Idx node_idx, node;
-  re_sift_context_t local_sctx;
-  Idx first_idx = search_cur_bkref_entry (mctx, str_idx);
-
-  if (first_idx == REG_MISSING)
-    return REG_NOERROR;
-
-  local_sctx.sifted_states = NULL; /* Mark that it hasn't been initialized.  */
-
-  for (node_idx = 0; node_idx < candidates->nelem; ++node_idx)
-    {
-      Idx enabled_idx;
-      re_token_type_t type;
-      struct re_backref_cache_entry *entry;
-      node = candidates->elems[node_idx];
-      type = dfa->nodes[node].type;
-      /* Avoid infinite loop for the REs like "()\1+".  */
-      if (node == sctx->last_node && str_idx == sctx->last_str_idx)
-	continue;
-      if (type != OP_BACK_REF)
-	continue;
-
-      entry = mctx->bkref_ents + first_idx;
-      enabled_idx = first_idx;
-      do
-	{
-	  Idx subexp_len;
-	  Idx to_idx;
-	  Idx dst_node;
-	  bool ok;
-	  re_dfastate_t *cur_state;
-
-	  if (entry->node != node)
-	    continue;
-	  subexp_len = entry->subexp_to - entry->subexp_from;
-	  to_idx = str_idx + subexp_len;
-	  dst_node = (subexp_len ? dfa->nexts[node]
-		      : dfa->edests[node].elems[0]);
-
-	  if (to_idx > sctx->last_str_idx
-	      || sctx->sifted_states[to_idx] == NULL
-	      || !STATE_NODE_CONTAINS (sctx->sifted_states[to_idx], dst_node)
-	      || check_dst_limits (mctx, &sctx->limits, node,
-				   str_idx, dst_node, to_idx))
-	    continue;
-
-	  if (local_sctx.sifted_states == NULL)
-	    {
-	      local_sctx = *sctx;
-	      err = re_node_set_init_copy (&local_sctx.limits, &sctx->limits);
-	      if (BE (err != REG_NOERROR, 0))
-		goto free_return;
-	    }
-	  local_sctx.last_node = node;
-	  local_sctx.last_str_idx = str_idx;
-	  ok = re_node_set_insert (&local_sctx.limits, enabled_idx);
-	  if (BE (! ok, 0))
-	    {
-	      err = REG_ESPACE;
-	      goto free_return;
-	    }
-	  cur_state = local_sctx.sifted_states[str_idx];
-	  err = sift_states_backward (mctx, &local_sctx);
-	  if (BE (err != REG_NOERROR, 0))
-	    goto free_return;
-	  if (sctx->limited_states != NULL)
-	    {
-	      err = merge_state_array (dfa, sctx->limited_states,
-				       local_sctx.sifted_states,
-				       str_idx + 1);
-	      if (BE (err != REG_NOERROR, 0))
-		goto free_return;
-	    }
-	  local_sctx.sifted_states[str_idx] = cur_state;
-	  re_node_set_remove (&local_sctx.limits, enabled_idx);
-
-	  /* mctx->bkref_ents may have changed, reload the pointer.  */
-	  entry = mctx->bkref_ents + enabled_idx;
-	}
-      while (enabled_idx++, entry++->more);
-    }
-  err = REG_NOERROR;
- free_return:
-  if (local_sctx.sifted_states != NULL)
-    {
-      re_node_set_free (&local_sctx.limits);
-    }
-
-  return err;
-}
-
-
-#ifdef RE_ENABLE_I18N
-static int
-internal_function
-sift_states_iter_mb (const re_match_context_t *mctx, re_sift_context_t *sctx,
-		     Idx node_idx, Idx str_idx, Idx max_str_idx)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  int naccepted;
-  /* Check the node can accept "multi byte".  */
-  naccepted = check_node_accept_bytes (dfa, node_idx, &mctx->input, str_idx);
-  if (naccepted > 0 && str_idx + naccepted <= max_str_idx &&
-      !STATE_NODE_CONTAINS (sctx->sifted_states[str_idx + naccepted],
-			    dfa->nexts[node_idx]))
-    /* The node can't accept the "multi byte", or the
-       destination was already thrown away, then the node
-       could't accept the current input "multi byte".   */
-    naccepted = 0;
-  /* Otherwise, it is sure that the node could accept
-     'naccepted' bytes input.  */
-  return naccepted;
-}
-#endif /* RE_ENABLE_I18N */
-
-
-/* Functions for state transition.  */
-
-/* Return the next state to which the current state STATE will transit by
-   accepting the current input byte, and update STATE_LOG if necessary.
-   If STATE can accept a multibyte char/collating element/back reference
-   update the destination of STATE_LOG.  */
-
-static re_dfastate_t *
-internal_function __attribute_warn_unused_result__
-transit_state (reg_errcode_t *err, re_match_context_t *mctx,
-	       re_dfastate_t *state)
-{
-  re_dfastate_t **trtable;
-  unsigned char ch;
-
-#ifdef RE_ENABLE_I18N
-  /* If the current state can accept multibyte.  */
-  if (BE (state->accept_mb, 0))
-    {
-      *err = transit_state_mb (mctx, state);
-      if (BE (*err != REG_NOERROR, 0))
-	return NULL;
-    }
-#endif /* RE_ENABLE_I18N */
-
-  /* Then decide the next state with the single byte.  */
-#if 0
-  if (0)
-    /* don't use transition table  */
-    return transit_state_sb (err, mctx, state);
-#endif
-
-  /* Use transition table  */
-  ch = re_string_fetch_byte (&mctx->input);
-  for (;;)
-    {
-      trtable = state->trtable;
-      if (BE (trtable != NULL, 1))
-	return trtable[ch];
-
-      trtable = state->word_trtable;
-      if (BE (trtable != NULL, 1))
-	{
-	  unsigned int context;
-	  context
-	    = re_string_context_at (&mctx->input,
-				    re_string_cur_idx (&mctx->input) - 1,
-				    mctx->eflags);
-	  if (IS_WORD_CONTEXT (context))
-	    return trtable[ch + SBC_MAX];
-	  else
-	    return trtable[ch];
-	}
-
-      if (!build_trtable (mctx->dfa, state))
-	{
-	  *err = REG_ESPACE;
-	  return NULL;
-	}
-
-      /* Retry, we now have a transition table.  */
-    }
-}
-
-/* Update the state_log if we need */
-static re_dfastate_t *
-internal_function
-merge_state_with_log (reg_errcode_t *err, re_match_context_t *mctx,
-		      re_dfastate_t *next_state)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  Idx cur_idx = re_string_cur_idx (&mctx->input);
-
-  if (cur_idx > mctx->state_log_top)
-    {
-      mctx->state_log[cur_idx] = next_state;
-      mctx->state_log_top = cur_idx;
-    }
-  else if (mctx->state_log[cur_idx] == 0)
-    {
-      mctx->state_log[cur_idx] = next_state;
-    }
-  else
-    {
-      re_dfastate_t *pstate;
-      unsigned int context;
-      re_node_set next_nodes, *log_nodes, *table_nodes = NULL;
-      /* If (state_log[cur_idx] != 0), it implies that cur_idx is
-	 the destination of a multibyte char/collating element/
-	 back reference.  Then the next state is the union set of
-	 these destinations and the results of the transition table.  */
-      pstate = mctx->state_log[cur_idx];
-      log_nodes = pstate->entrance_nodes;
-      if (next_state != NULL)
-	{
-	  table_nodes = next_state->entrance_nodes;
-	  *err = re_node_set_init_union (&next_nodes, table_nodes,
-					     log_nodes);
-	  if (BE (*err != REG_NOERROR, 0))
-	    return NULL;
-	}
-      else
-	next_nodes = *log_nodes;
-      /* Note: We already add the nodes of the initial state,
-	 then we don't need to add them here.  */
-
-      context = re_string_context_at (&mctx->input,
-				      re_string_cur_idx (&mctx->input) - 1,
-				      mctx->eflags);
-      next_state = mctx->state_log[cur_idx]
-	= re_acquire_state_context (err, dfa, &next_nodes, context);
-      /* We don't need to check errors here, since the return value of
-	 this function is next_state and ERR is already set.  */
-
-      if (table_nodes != NULL)
-	re_node_set_free (&next_nodes);
-    }
-
-  if (BE (dfa->nbackref, 0) && next_state != NULL)
-    {
-      /* Check OP_OPEN_SUBEXP in the current state in case that we use them
-	 later.  We must check them here, since the back references in the
-	 next state might use them.  */
-      *err = check_subexp_matching_top (mctx, &next_state->nodes,
-					cur_idx);
-      if (BE (*err != REG_NOERROR, 0))
-	return NULL;
-
-      /* If the next state has back references.  */
-      if (next_state->has_backref)
-	{
-	  *err = transit_state_bkref (mctx, &next_state->nodes);
-	  if (BE (*err != REG_NOERROR, 0))
-	    return NULL;
-	  next_state = mctx->state_log[cur_idx];
-	}
-    }
-
-  return next_state;
-}
-
-/* Skip bytes in the input that correspond to part of a
-   multi-byte match, then look in the log for a state
-   from which to restart matching.  */
-static re_dfastate_t *
-internal_function
-find_recover_state (reg_errcode_t *err, re_match_context_t *mctx)
-{
-  re_dfastate_t *cur_state;
-  do
-    {
-      Idx max = mctx->state_log_top;
-      Idx cur_str_idx = re_string_cur_idx (&mctx->input);
-
-      do
-	{
-	  if (++cur_str_idx > max)
-	    return NULL;
-	  re_string_skip_bytes (&mctx->input, 1);
-	}
-      while (mctx->state_log[cur_str_idx] == NULL);
-
-      cur_state = merge_state_with_log (err, mctx, NULL);
-    }
-  while (*err == REG_NOERROR && cur_state == NULL);
-  return cur_state;
-}
-
-/* Helper functions for transit_state.  */
-
-/* From the node set CUR_NODES, pick up the nodes whose types are
-   OP_OPEN_SUBEXP and which have corresponding back references in the regular
-   expression. And register them to use them later for evaluating the
-   corresponding back references.  */
-
-static reg_errcode_t
-internal_function
-check_subexp_matching_top (re_match_context_t *mctx, re_node_set *cur_nodes,
-			   Idx str_idx)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  Idx node_idx;
-  reg_errcode_t err;
-
-  /* TODO: This isn't efficient.
-	   Because there might be more than one nodes whose types are
-	   OP_OPEN_SUBEXP and whose index is SUBEXP_IDX, we must check all
-	   nodes.
-	   E.g. RE: (a){2}  */
-  for (node_idx = 0; node_idx < cur_nodes->nelem; ++node_idx)
-    {
-      Idx node = cur_nodes->elems[node_idx];
-      if (dfa->nodes[node].type == OP_OPEN_SUBEXP
-	  && dfa->nodes[node].opr.idx < BITSET_WORD_BITS
-	  && (dfa->used_bkref_map
-	      & ((bitset_word_t) 1 << dfa->nodes[node].opr.idx)))
-	{
-	  err = match_ctx_add_subtop (mctx, node, str_idx);
-	  if (BE (err != REG_NOERROR, 0))
-	    return err;
-	}
-    }
-  return REG_NOERROR;
-}
-
-#if 0
-/* Return the next state to which the current state STATE will transit by
-   accepting the current input byte.  */
-
-static re_dfastate_t *
-transit_state_sb (reg_errcode_t *err, re_match_context_t *mctx,
-		  re_dfastate_t *state)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  re_node_set next_nodes;
-  re_dfastate_t *next_state;
-  Idx node_cnt, cur_str_idx = re_string_cur_idx (&mctx->input);
-  unsigned int context;
-
-  *err = re_node_set_alloc (&next_nodes, state->nodes.nelem + 1);
-  if (BE (*err != REG_NOERROR, 0))
-    return NULL;
-  for (node_cnt = 0; node_cnt < state->nodes.nelem; ++node_cnt)
-    {
-      Idx cur_node = state->nodes.elems[node_cnt];
-      if (check_node_accept (mctx, dfa->nodes + cur_node, cur_str_idx))
-	{
-	  *err = re_node_set_merge (&next_nodes,
-				    dfa->eclosures + dfa->nexts[cur_node]);
-	  if (BE (*err != REG_NOERROR, 0))
-	    {
-	      re_node_set_free (&next_nodes);
-	      return NULL;
-	    }
-	}
-    }
-  context = re_string_context_at (&mctx->input, cur_str_idx, mctx->eflags);
-  next_state = re_acquire_state_context (err, dfa, &next_nodes, context);
-  /* We don't need to check errors here, since the return value of
-     this function is next_state and ERR is already set.  */
-
-  re_node_set_free (&next_nodes);
-  re_string_skip_bytes (&mctx->input, 1);
-  return next_state;
-}
-#endif
-
-#ifdef RE_ENABLE_I18N
-static reg_errcode_t
-internal_function
-transit_state_mb (re_match_context_t *mctx, re_dfastate_t *pstate)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  reg_errcode_t err;
-  Idx i;
-
-  for (i = 0; i < pstate->nodes.nelem; ++i)
-    {
-      re_node_set dest_nodes, *new_nodes;
-      Idx cur_node_idx = pstate->nodes.elems[i];
-      int naccepted;
-      Idx dest_idx;
-      unsigned int context;
-      re_dfastate_t *dest_state;
-
-      if (!dfa->nodes[cur_node_idx].accept_mb)
-	continue;
-
-      if (dfa->nodes[cur_node_idx].constraint)
-	{
-	  context = re_string_context_at (&mctx->input,
-					  re_string_cur_idx (&mctx->input),
-					  mctx->eflags);
-	  if (NOT_SATISFY_NEXT_CONSTRAINT (dfa->nodes[cur_node_idx].constraint,
-					   context))
-	    continue;
-	}
-
-      /* How many bytes the node can accept?  */
-      naccepted = check_node_accept_bytes (dfa, cur_node_idx, &mctx->input,
-					   re_string_cur_idx (&mctx->input));
-      if (naccepted == 0)
-	continue;
-
-      /* The node can accepts 'naccepted' bytes.  */
-      dest_idx = re_string_cur_idx (&mctx->input) + naccepted;
-      mctx->max_mb_elem_len = ((mctx->max_mb_elem_len < naccepted) ? naccepted
-			       : mctx->max_mb_elem_len);
-      err = clean_state_log_if_needed (mctx, dest_idx);
-      if (BE (err != REG_NOERROR, 0))
-	return err;
-#ifdef DEBUG
-      assert (dfa->nexts[cur_node_idx] != REG_MISSING);
-#endif
-      new_nodes = dfa->eclosures + dfa->nexts[cur_node_idx];
-
-      dest_state = mctx->state_log[dest_idx];
-      if (dest_state == NULL)
-	dest_nodes = *new_nodes;
-      else
-	{
-	  err = re_node_set_init_union (&dest_nodes,
-					dest_state->entrance_nodes, new_nodes);
-	  if (BE (err != REG_NOERROR, 0))
-	    return err;
-	}
-      context = re_string_context_at (&mctx->input, dest_idx - 1,
-				      mctx->eflags);
-      mctx->state_log[dest_idx]
-	= re_acquire_state_context (&err, dfa, &dest_nodes, context);
-      if (dest_state != NULL)
-	re_node_set_free (&dest_nodes);
-      if (BE (mctx->state_log[dest_idx] == NULL && err != REG_NOERROR, 0))
-	return err;
-    }
-  return REG_NOERROR;
-}
-#endif /* RE_ENABLE_I18N */
-
-static reg_errcode_t
-internal_function
-transit_state_bkref (re_match_context_t *mctx, const re_node_set *nodes)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  reg_errcode_t err;
-  Idx i;
-  Idx cur_str_idx = re_string_cur_idx (&mctx->input);
-
-  for (i = 0; i < nodes->nelem; ++i)
-    {
-      Idx dest_str_idx, prev_nelem, bkc_idx;
-      Idx node_idx = nodes->elems[i];
-      unsigned int context;
-      const re_token_t *node = dfa->nodes + node_idx;
-      re_node_set *new_dest_nodes;
-
-      /* Check whether 'node' is a backreference or not.  */
-      if (node->type != OP_BACK_REF)
-	continue;
-
-      if (node->constraint)
-	{
-	  context = re_string_context_at (&mctx->input, cur_str_idx,
-					  mctx->eflags);
-	  if (NOT_SATISFY_NEXT_CONSTRAINT (node->constraint, context))
-	    continue;
-	}
-
-      /* 'node' is a backreference.
-	 Check the substring which the substring matched.  */
-      bkc_idx = mctx->nbkref_ents;
-      err = get_subexp (mctx, node_idx, cur_str_idx);
-      if (BE (err != REG_NOERROR, 0))
-	goto free_return;
-
-      /* And add the epsilon closures (which is 'new_dest_nodes') of
-	 the backreference to appropriate state_log.  */
-#ifdef DEBUG
-      assert (dfa->nexts[node_idx] != REG_MISSING);
-#endif
-      for (; bkc_idx < mctx->nbkref_ents; ++bkc_idx)
-	{
-	  Idx subexp_len;
-	  re_dfastate_t *dest_state;
-	  struct re_backref_cache_entry *bkref_ent;
-	  bkref_ent = mctx->bkref_ents + bkc_idx;
-	  if (bkref_ent->node != node_idx || bkref_ent->str_idx != cur_str_idx)
-	    continue;
-	  subexp_len = bkref_ent->subexp_to - bkref_ent->subexp_from;
-	  new_dest_nodes = (subexp_len == 0
-			    ? dfa->eclosures + dfa->edests[node_idx].elems[0]
-			    : dfa->eclosures + dfa->nexts[node_idx]);
-	  dest_str_idx = (cur_str_idx + bkref_ent->subexp_to
-			  - bkref_ent->subexp_from);
-	  context = re_string_context_at (&mctx->input, dest_str_idx - 1,
-					  mctx->eflags);
-	  dest_state = mctx->state_log[dest_str_idx];
-	  prev_nelem = ((mctx->state_log[cur_str_idx] == NULL) ? 0
-			: mctx->state_log[cur_str_idx]->nodes.nelem);
-	  /* Add 'new_dest_node' to state_log.  */
-	  if (dest_state == NULL)
-	    {
-	      mctx->state_log[dest_str_idx]
-		= re_acquire_state_context (&err, dfa, new_dest_nodes,
-					    context);
-	      if (BE (mctx->state_log[dest_str_idx] == NULL
-		      && err != REG_NOERROR, 0))
-		goto free_return;
-	    }
-	  else
-	    {
-	      re_node_set dest_nodes;
-	      err = re_node_set_init_union (&dest_nodes,
-					    dest_state->entrance_nodes,
-					    new_dest_nodes);
-	      if (BE (err != REG_NOERROR, 0))
-		{
-		  re_node_set_free (&dest_nodes);
-		  goto free_return;
-		}
-	      mctx->state_log[dest_str_idx]
-		= re_acquire_state_context (&err, dfa, &dest_nodes, context);
-	      re_node_set_free (&dest_nodes);
-	      if (BE (mctx->state_log[dest_str_idx] == NULL
-		      && err != REG_NOERROR, 0))
-		goto free_return;
-	    }
-	  /* We need to check recursively if the backreference can epsilon
-	     transit.  */
-	  if (subexp_len == 0
-	      && mctx->state_log[cur_str_idx]->nodes.nelem > prev_nelem)
-	    {
-	      err = check_subexp_matching_top (mctx, new_dest_nodes,
-					       cur_str_idx);
-	      if (BE (err != REG_NOERROR, 0))
-		goto free_return;
-	      err = transit_state_bkref (mctx, new_dest_nodes);
-	      if (BE (err != REG_NOERROR, 0))
-		goto free_return;
-	    }
-	}
-    }
-  err = REG_NOERROR;
- free_return:
-  return err;
-}
-
-/* Enumerate all the candidates which the backreference BKREF_NODE can match
-   at BKREF_STR_IDX, and register them by match_ctx_add_entry().
-   Note that we might collect inappropriate candidates here.
-   However, the cost of checking them strictly here is too high, then we
-   delay these checking for prune_impossible_nodes().  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-get_subexp (re_match_context_t *mctx, Idx bkref_node, Idx bkref_str_idx)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  Idx subexp_num, sub_top_idx;
-  const char *buf = (const char *) re_string_get_buffer (&mctx->input);
-  /* Return if we have already checked BKREF_NODE at BKREF_STR_IDX.  */
-  Idx cache_idx = search_cur_bkref_entry (mctx, bkref_str_idx);
-  if (cache_idx != REG_MISSING)
-    {
-      const struct re_backref_cache_entry *entry
-	= mctx->bkref_ents + cache_idx;
-      do
-	if (entry->node == bkref_node)
-	  return REG_NOERROR; /* We already checked it.  */
-      while (entry++->more);
-    }
-
-  subexp_num = dfa->nodes[bkref_node].opr.idx;
-
-  /* For each sub expression  */
-  for (sub_top_idx = 0; sub_top_idx < mctx->nsub_tops; ++sub_top_idx)
-    {
-      reg_errcode_t err;
-      re_sub_match_top_t *sub_top = mctx->sub_tops[sub_top_idx];
-      re_sub_match_last_t *sub_last;
-      Idx sub_last_idx, sl_str, bkref_str_off;
-
-      if (dfa->nodes[sub_top->node].opr.idx != subexp_num)
-	continue; /* It isn't related.  */
-
-      sl_str = sub_top->str_idx;
-      bkref_str_off = bkref_str_idx;
-      /* At first, check the last node of sub expressions we already
-	 evaluated.  */
-      for (sub_last_idx = 0; sub_last_idx < sub_top->nlasts; ++sub_last_idx)
-	{
-	  regoff_t sl_str_diff;
-	  sub_last = sub_top->lasts[sub_last_idx];
-	  sl_str_diff = sub_last->str_idx - sl_str;
-	  /* The matched string by the sub expression match with the substring
-	     at the back reference?  */
-	  if (sl_str_diff > 0)
-	    {
-	      if (BE (bkref_str_off + sl_str_diff > mctx->input.valid_len, 0))
-		{
-		  /* Not enough chars for a successful match.  */
-		  if (bkref_str_off + sl_str_diff > mctx->input.len)
-		    break;
-
-		  err = clean_state_log_if_needed (mctx,
-						   bkref_str_off
-						   + sl_str_diff);
-		  if (BE (err != REG_NOERROR, 0))
-		    return err;
-		  buf = (const char *) re_string_get_buffer (&mctx->input);
-		}
-	      if (memcmp (buf + bkref_str_off, buf + sl_str, sl_str_diff) != 0)
-		/* We don't need to search this sub expression any more.  */
-		break;
-	    }
-	  bkref_str_off += sl_str_diff;
-	  sl_str += sl_str_diff;
-	  err = get_subexp_sub (mctx, sub_top, sub_last, bkref_node,
-				bkref_str_idx);
-
-	  /* Reload buf, since the preceding call might have reallocated
-	     the buffer.  */
-	  buf = (const char *) re_string_get_buffer (&mctx->input);
-
-	  if (err == REG_NOMATCH)
-	    continue;
-	  if (BE (err != REG_NOERROR, 0))
-	    return err;
-	}
-
-      if (sub_last_idx < sub_top->nlasts)
-	continue;
-      if (sub_last_idx > 0)
-	++sl_str;
-      /* Then, search for the other last nodes of the sub expression.  */
-      for (; sl_str <= bkref_str_idx; ++sl_str)
-	{
-	  Idx cls_node;
-	  regoff_t sl_str_off;
-	  const re_node_set *nodes;
-	  sl_str_off = sl_str - sub_top->str_idx;
-	  /* The matched string by the sub expression match with the substring
-	     at the back reference?  */
-	  if (sl_str_off > 0)
-	    {
-	      if (BE (bkref_str_off >= mctx->input.valid_len, 0))
-		{
-		  /* If we are at the end of the input, we cannot match.  */
-		  if (bkref_str_off >= mctx->input.len)
-		    break;
-
-		  err = extend_buffers (mctx, bkref_str_off + 1);
-		  if (BE (err != REG_NOERROR, 0))
-		    return err;
-
-		  buf = (const char *) re_string_get_buffer (&mctx->input);
-		}
-	      if (buf [bkref_str_off++] != buf[sl_str - 1])
-		break; /* We don't need to search this sub expression
-			  any more.  */
-	    }
-	  if (mctx->state_log[sl_str] == NULL)
-	    continue;
-	  /* Does this state have a ')' of the sub expression?  */
-	  nodes = &mctx->state_log[sl_str]->nodes;
-	  cls_node = find_subexp_node (dfa, nodes, subexp_num,
-				       OP_CLOSE_SUBEXP);
-	  if (cls_node == REG_MISSING)
-	    continue; /* No.  */
-	  if (sub_top->path == NULL)
-	    {
-	      sub_top->path = calloc (sizeof (state_array_t),
-				      sl_str - sub_top->str_idx + 1);
-	      if (sub_top->path == NULL)
-		return REG_ESPACE;
-	    }
-	  /* Can the OP_OPEN_SUBEXP node arrive the OP_CLOSE_SUBEXP node
-	     in the current context?  */
-	  err = check_arrival (mctx, sub_top->path, sub_top->node,
-			       sub_top->str_idx, cls_node, sl_str,
-			       OP_CLOSE_SUBEXP);
-	  if (err == REG_NOMATCH)
-	      continue;
-	  if (BE (err != REG_NOERROR, 0))
-	      return err;
-	  sub_last = match_ctx_add_sublast (sub_top, cls_node, sl_str);
-	  if (BE (sub_last == NULL, 0))
-	    return REG_ESPACE;
-	  err = get_subexp_sub (mctx, sub_top, sub_last, bkref_node,
-				bkref_str_idx);
-	  if (err == REG_NOMATCH)
-	    continue;
-	}
-    }
-  return REG_NOERROR;
-}
-
-/* Helper functions for get_subexp().  */
-
-/* Check SUB_LAST can arrive to the back reference BKREF_NODE at BKREF_STR.
-   If it can arrive, register the sub expression expressed with SUB_TOP
-   and SUB_LAST.  */
-
-static reg_errcode_t
-internal_function
-get_subexp_sub (re_match_context_t *mctx, const re_sub_match_top_t *sub_top,
-		re_sub_match_last_t *sub_last, Idx bkref_node, Idx bkref_str)
-{
-  reg_errcode_t err;
-  Idx to_idx;
-  /* Can the subexpression arrive the back reference?  */
-  err = check_arrival (mctx, &sub_last->path, sub_last->node,
-		       sub_last->str_idx, bkref_node, bkref_str,
-		       OP_OPEN_SUBEXP);
-  if (err != REG_NOERROR)
-    return err;
-  err = match_ctx_add_entry (mctx, bkref_node, bkref_str, sub_top->str_idx,
-			     sub_last->str_idx);
-  if (BE (err != REG_NOERROR, 0))
-    return err;
-  to_idx = bkref_str + sub_last->str_idx - sub_top->str_idx;
-  return clean_state_log_if_needed (mctx, to_idx);
-}
-
-/* Find the first node which is '(' or ')' and whose index is SUBEXP_IDX.
-   Search '(' if FL_OPEN, or search ')' otherwise.
-   TODO: This function isn't efficient...
-	 Because there might be more than one nodes whose types are
-	 OP_OPEN_SUBEXP and whose index is SUBEXP_IDX, we must check all
-	 nodes.
-	 E.g. RE: (a){2}  */
-
-static Idx
-internal_function
-find_subexp_node (const re_dfa_t *dfa, const re_node_set *nodes,
-		  Idx subexp_idx, int type)
-{
-  Idx cls_idx;
-  for (cls_idx = 0; cls_idx < nodes->nelem; ++cls_idx)
-    {
-      Idx cls_node = nodes->elems[cls_idx];
-      const re_token_t *node = dfa->nodes + cls_node;
-      if (node->type == type
-	  && node->opr.idx == subexp_idx)
-	return cls_node;
-    }
-  return REG_MISSING;
-}
-
-/* Check whether the node TOP_NODE at TOP_STR can arrive to the node
-   LAST_NODE at LAST_STR.  We record the path onto PATH since it will be
-   heavily reused.
-   Return REG_NOERROR if it can arrive, or REG_NOMATCH otherwise.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-check_arrival (re_match_context_t *mctx, state_array_t *path, Idx top_node,
-	       Idx top_str, Idx last_node, Idx last_str, int type)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  reg_errcode_t err = REG_NOERROR;
-  Idx subexp_num, backup_cur_idx, str_idx, null_cnt;
-  re_dfastate_t *cur_state = NULL;
-  re_node_set *cur_nodes, next_nodes;
-  re_dfastate_t **backup_state_log;
-  unsigned int context;
-
-  subexp_num = dfa->nodes[top_node].opr.idx;
-  /* Extend the buffer if we need.  */
-  if (BE (path->alloc < last_str + mctx->max_mb_elem_len + 1, 0))
-    {
-      re_dfastate_t **new_array;
-      Idx old_alloc = path->alloc;
-      Idx incr_alloc = last_str + mctx->max_mb_elem_len + 1;
-      Idx new_alloc;
-      if (BE (IDX_MAX - old_alloc < incr_alloc, 0))
-	return REG_ESPACE;
-      new_alloc = old_alloc + incr_alloc;
-      if (BE (SIZE_MAX / sizeof (re_dfastate_t *) < new_alloc, 0))
-	return REG_ESPACE;
-      new_array = re_realloc (path->array, re_dfastate_t *, new_alloc);
-      if (BE (new_array == NULL, 0))
-	return REG_ESPACE;
-      path->array = new_array;
-      path->alloc = new_alloc;
-      memset (new_array + old_alloc, '\0',
-	      sizeof (re_dfastate_t *) * (path->alloc - old_alloc));
-    }
-
-  str_idx = path->next_idx ? path->next_idx : top_str;
-
-  /* Temporary modify MCTX.  */
-  backup_state_log = mctx->state_log;
-  backup_cur_idx = mctx->input.cur_idx;
-  mctx->state_log = path->array;
-  mctx->input.cur_idx = str_idx;
-
-  /* Setup initial node set.  */
-  context = re_string_context_at (&mctx->input, str_idx - 1, mctx->eflags);
-  if (str_idx == top_str)
-    {
-      err = re_node_set_init_1 (&next_nodes, top_node);
-      if (BE (err != REG_NOERROR, 0))
-	return err;
-      err = check_arrival_expand_ecl (dfa, &next_nodes, subexp_num, type);
-      if (BE (err != REG_NOERROR, 0))
-	{
-	  re_node_set_free (&next_nodes);
-	  return err;
-	}
-    }
-  else
-    {
-      cur_state = mctx->state_log[str_idx];
-      if (cur_state && cur_state->has_backref)
-	{
-	  err = re_node_set_init_copy (&next_nodes, &cur_state->nodes);
-	  if (BE (err != REG_NOERROR, 0))
-	    return err;
-	}
-      else
-	re_node_set_init_empty (&next_nodes);
-    }
-  if (str_idx == top_str || (cur_state && cur_state->has_backref))
-    {
-      if (next_nodes.nelem)
-	{
-	  err = expand_bkref_cache (mctx, &next_nodes, str_idx,
-				    subexp_num, type);
-	  if (BE (err != REG_NOERROR, 0))
-	    {
-	      re_node_set_free (&next_nodes);
-	      return err;
-	    }
-	}
-      cur_state = re_acquire_state_context (&err, dfa, &next_nodes, context);
-      if (BE (cur_state == NULL && err != REG_NOERROR, 0))
-	{
-	  re_node_set_free (&next_nodes);
-	  return err;
-	}
-      mctx->state_log[str_idx] = cur_state;
-    }
-
-  for (null_cnt = 0; str_idx < last_str && null_cnt <= mctx->max_mb_elem_len;)
-    {
-      re_node_set_empty (&next_nodes);
-      if (mctx->state_log[str_idx + 1])
-	{
-	  err = re_node_set_merge (&next_nodes,
-				   &mctx->state_log[str_idx + 1]->nodes);
-	  if (BE (err != REG_NOERROR, 0))
-	    {
-	      re_node_set_free (&next_nodes);
-	      return err;
-	    }
-	}
-      if (cur_state)
-	{
-	  err = check_arrival_add_next_nodes (mctx, str_idx,
-					      &cur_state->non_eps_nodes,
-					      &next_nodes);
-	  if (BE (err != REG_NOERROR, 0))
-	    {
-	      re_node_set_free (&next_nodes);
-	      return err;
-	    }
-	}
-      ++str_idx;
-      if (next_nodes.nelem)
-	{
-	  err = check_arrival_expand_ecl (dfa, &next_nodes, subexp_num, type);
-	  if (BE (err != REG_NOERROR, 0))
-	    {
-	      re_node_set_free (&next_nodes);
-	      return err;
-	    }
-	  err = expand_bkref_cache (mctx, &next_nodes, str_idx,
-				    subexp_num, type);
-	  if (BE (err != REG_NOERROR, 0))
-	    {
-	      re_node_set_free (&next_nodes);
-	      return err;
-	    }
-	}
-      context = re_string_context_at (&mctx->input, str_idx - 1, mctx->eflags);
-      cur_state = re_acquire_state_context (&err, dfa, &next_nodes, context);
-      if (BE (cur_state == NULL && err != REG_NOERROR, 0))
-	{
-	  re_node_set_free (&next_nodes);
-	  return err;
-	}
-      mctx->state_log[str_idx] = cur_state;
-      null_cnt = cur_state == NULL ? null_cnt + 1 : 0;
-    }
-  re_node_set_free (&next_nodes);
-  cur_nodes = (mctx->state_log[last_str] == NULL ? NULL
-	       : &mctx->state_log[last_str]->nodes);
-  path->next_idx = str_idx;
-
-  /* Fix MCTX.  */
-  mctx->state_log = backup_state_log;
-  mctx->input.cur_idx = backup_cur_idx;
-
-  /* Then check the current node set has the node LAST_NODE.  */
-  if (cur_nodes != NULL && re_node_set_contains (cur_nodes, last_node))
-    return REG_NOERROR;
-
-  return REG_NOMATCH;
-}
-
-/* Helper functions for check_arrival.  */
-
-/* Calculate the destination nodes of CUR_NODES at STR_IDX, and append them
-   to NEXT_NODES.
-   TODO: This function is similar to the functions transit_state*(),
-	 however this function has many additional works.
-	 Can't we unify them?  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-check_arrival_add_next_nodes (re_match_context_t *mctx, Idx str_idx,
-			      re_node_set *cur_nodes, re_node_set *next_nodes)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  bool ok;
-  Idx cur_idx;
-#ifdef RE_ENABLE_I18N
-  reg_errcode_t err = REG_NOERROR;
-#endif
-  re_node_set union_set;
-  re_node_set_init_empty (&union_set);
-  for (cur_idx = 0; cur_idx < cur_nodes->nelem; ++cur_idx)
-    {
-      int naccepted = 0;
-      Idx cur_node = cur_nodes->elems[cur_idx];
-#ifdef DEBUG
-      re_token_type_t type = dfa->nodes[cur_node].type;
-      assert (!IS_EPSILON_NODE (type));
-#endif
-#ifdef RE_ENABLE_I18N
-      /* If the node may accept "multi byte".  */
-      if (dfa->nodes[cur_node].accept_mb)
-	{
-	  naccepted = check_node_accept_bytes (dfa, cur_node, &mctx->input,
-					       str_idx);
-	  if (naccepted > 1)
-	    {
-	      re_dfastate_t *dest_state;
-	      Idx next_node = dfa->nexts[cur_node];
-	      Idx next_idx = str_idx + naccepted;
-	      dest_state = mctx->state_log[next_idx];
-	      re_node_set_empty (&union_set);
-	      if (dest_state)
-		{
-		  err = re_node_set_merge (&union_set, &dest_state->nodes);
-		  if (BE (err != REG_NOERROR, 0))
-		    {
-		      re_node_set_free (&union_set);
-		      return err;
-		    }
-		}
-	      ok = re_node_set_insert (&union_set, next_node);
-	      if (BE (! ok, 0))
-		{
-		  re_node_set_free (&union_set);
-		  return REG_ESPACE;
-		}
-	      mctx->state_log[next_idx] = re_acquire_state (&err, dfa,
-							    &union_set);
-	      if (BE (mctx->state_log[next_idx] == NULL
-		      && err != REG_NOERROR, 0))
-		{
-		  re_node_set_free (&union_set);
-		  return err;
-		}
-	    }
-	}
-#endif /* RE_ENABLE_I18N */
-      if (naccepted
-	  || check_node_accept (mctx, dfa->nodes + cur_node, str_idx))
-	{
-	  ok = re_node_set_insert (next_nodes, dfa->nexts[cur_node]);
-	  if (BE (! ok, 0))
-	    {
-	      re_node_set_free (&union_set);
-	      return REG_ESPACE;
-	    }
-	}
-    }
-  re_node_set_free (&union_set);
-  return REG_NOERROR;
-}
-
-/* For all the nodes in CUR_NODES, add the epsilon closures of them to
-   CUR_NODES, however exclude the nodes which are:
-    - inside the sub expression whose number is EX_SUBEXP, if FL_OPEN.
-    - out of the sub expression whose number is EX_SUBEXP, if !FL_OPEN.
-*/
-
-static reg_errcode_t
-internal_function
-check_arrival_expand_ecl (const re_dfa_t *dfa, re_node_set *cur_nodes,
-			  Idx ex_subexp, int type)
-{
-  reg_errcode_t err;
-  Idx idx, outside_node;
-  re_node_set new_nodes;
-#ifdef DEBUG
-  assert (cur_nodes->nelem);
-#endif
-  err = re_node_set_alloc (&new_nodes, cur_nodes->nelem);
-  if (BE (err != REG_NOERROR, 0))
-    return err;
-  /* Create a new node set NEW_NODES with the nodes which are epsilon
-     closures of the node in CUR_NODES.  */
-
-  for (idx = 0; idx < cur_nodes->nelem; ++idx)
-    {
-      Idx cur_node = cur_nodes->elems[idx];
-      const re_node_set *eclosure = dfa->eclosures + cur_node;
-      outside_node = find_subexp_node (dfa, eclosure, ex_subexp, type);
-      if (outside_node == REG_MISSING)
-	{
-	  /* There are no problematic nodes, just merge them.  */
-	  err = re_node_set_merge (&new_nodes, eclosure);
-	  if (BE (err != REG_NOERROR, 0))
-	    {
-	      re_node_set_free (&new_nodes);
-	      return err;
-	    }
-	}
-      else
-	{
-	  /* There are problematic nodes, re-calculate incrementally.  */
-	  err = check_arrival_expand_ecl_sub (dfa, &new_nodes, cur_node,
-					      ex_subexp, type);
-	  if (BE (err != REG_NOERROR, 0))
-	    {
-	      re_node_set_free (&new_nodes);
-	      return err;
-	    }
-	}
-    }
-  re_node_set_free (cur_nodes);
-  *cur_nodes = new_nodes;
-  return REG_NOERROR;
-}
-
-/* Helper function for check_arrival_expand_ecl.
-   Check incrementally the epsilon closure of TARGET, and if it isn't
-   problematic append it to DST_NODES.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-check_arrival_expand_ecl_sub (const re_dfa_t *dfa, re_node_set *dst_nodes,
-			      Idx target, Idx ex_subexp, int type)
-{
-  Idx cur_node;
-  for (cur_node = target; !re_node_set_contains (dst_nodes, cur_node);)
-    {
-      bool ok;
-
-      if (dfa->nodes[cur_node].type == type
-	  && dfa->nodes[cur_node].opr.idx == ex_subexp)
-	{
-	  if (type == OP_CLOSE_SUBEXP)
-	    {
-	      ok = re_node_set_insert (dst_nodes, cur_node);
-	      if (BE (! ok, 0))
-		return REG_ESPACE;
-	    }
-	  break;
-	}
-      ok = re_node_set_insert (dst_nodes, cur_node);
-      if (BE (! ok, 0))
-	return REG_ESPACE;
-      if (dfa->edests[cur_node].nelem == 0)
-	break;
-      if (dfa->edests[cur_node].nelem == 2)
-	{
-	  reg_errcode_t err;
-	  err = check_arrival_expand_ecl_sub (dfa, dst_nodes,
-					      dfa->edests[cur_node].elems[1],
-					      ex_subexp, type);
-	  if (BE (err != REG_NOERROR, 0))
-	    return err;
-	}
-      cur_node = dfa->edests[cur_node].elems[0];
-    }
-  return REG_NOERROR;
-}
-
-
-/* For all the back references in the current state, calculate the
-   destination of the back references by the appropriate entry
-   in MCTX->BKREF_ENTS.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-expand_bkref_cache (re_match_context_t *mctx, re_node_set *cur_nodes,
-		    Idx cur_str, Idx subexp_num, int type)
-{
-  const re_dfa_t *const dfa = mctx->dfa;
-  reg_errcode_t err;
-  Idx cache_idx_start = search_cur_bkref_entry (mctx, cur_str);
-  struct re_backref_cache_entry *ent;
-
-  if (cache_idx_start == REG_MISSING)
-    return REG_NOERROR;
-
- restart:
-  ent = mctx->bkref_ents + cache_idx_start;
-  do
-    {
-      Idx to_idx, next_node;
-
-      /* Is this entry ENT is appropriate?  */
-      if (!re_node_set_contains (cur_nodes, ent->node))
-	continue; /* No.  */
-
-      to_idx = cur_str + ent->subexp_to - ent->subexp_from;
-      /* Calculate the destination of the back reference, and append it
-	 to MCTX->STATE_LOG.  */
-      if (to_idx == cur_str)
-	{
-	  /* The backreference did epsilon transit, we must re-check all the
-	     node in the current state.  */
-	  re_node_set new_dests;
-	  reg_errcode_t err2, err3;
-	  next_node = dfa->edests[ent->node].elems[0];
-	  if (re_node_set_contains (cur_nodes, next_node))
-	    continue;
-	  err = re_node_set_init_1 (&new_dests, next_node);
-	  err2 = check_arrival_expand_ecl (dfa, &new_dests, subexp_num, type);
-	  err3 = re_node_set_merge (cur_nodes, &new_dests);
-	  re_node_set_free (&new_dests);
-	  if (BE (err != REG_NOERROR || err2 != REG_NOERROR
-		  || err3 != REG_NOERROR, 0))
-	    {
-	      err = (err != REG_NOERROR ? err
-		     : (err2 != REG_NOERROR ? err2 : err3));
-	      return err;
-	    }
-	  /* TODO: It is still inefficient...  */
-	  goto restart;
-	}
-      else
-	{
-	  re_node_set union_set;
-	  next_node = dfa->nexts[ent->node];
-	  if (mctx->state_log[to_idx])
-	    {
-	      bool ok;
-	      if (re_node_set_contains (&mctx->state_log[to_idx]->nodes,
-					next_node))
-		continue;
-	      err = re_node_set_init_copy (&union_set,
-					   &mctx->state_log[to_idx]->nodes);
-	      ok = re_node_set_insert (&union_set, next_node);
-	      if (BE (err != REG_NOERROR || ! ok, 0))
-		{
-		  re_node_set_free (&union_set);
-		  err = err != REG_NOERROR ? err : REG_ESPACE;
-		  return err;
-		}
-	    }
-	  else
-	    {
-	      err = re_node_set_init_1 (&union_set, next_node);
-	      if (BE (err != REG_NOERROR, 0))
-		return err;
-	    }
-	  mctx->state_log[to_idx] = re_acquire_state (&err, dfa, &union_set);
-	  re_node_set_free (&union_set);
-	  if (BE (mctx->state_log[to_idx] == NULL
-		  && err != REG_NOERROR, 0))
-	    return err;
-	}
-    }
-  while (ent++->more);
-  return REG_NOERROR;
-}
-
-/* Build transition table for the state.
-   Return true if successful.  */
-
-static bool
-internal_function
-build_trtable (const re_dfa_t *dfa, re_dfastate_t *state)
-{
-  reg_errcode_t err;
-  Idx i, j;
-  int ch;
-  bool need_word_trtable = false;
-  bitset_word_t elem, mask;
-  bool dests_node_malloced = false;
-  bool dest_states_malloced = false;
-  Idx ndests; /* Number of the destination states from 'state'.  */
-  re_dfastate_t **trtable;
-  re_dfastate_t **dest_states = NULL, **dest_states_word, **dest_states_nl;
-  re_node_set follows, *dests_node;
-  bitset_t *dests_ch;
-  bitset_t acceptable;
-
-  struct dests_alloc
-  {
-    re_node_set dests_node[SBC_MAX];
-    bitset_t dests_ch[SBC_MAX];
-  } *dests_alloc;
-
-  /* We build DFA states which corresponds to the destination nodes
-     from 'state'.  'dests_node[i]' represents the nodes which i-th
-     destination state contains, and 'dests_ch[i]' represents the
-     characters which i-th destination state accepts.  */
-  if (__libc_use_alloca (sizeof (struct dests_alloc)))
-    dests_alloc = (struct dests_alloc *) alloca (sizeof (struct dests_alloc));
-  else
-    {
-      dests_alloc = re_malloc (struct dests_alloc, 1);
-      if (BE (dests_alloc == NULL, 0))
-	return false;
-      dests_node_malloced = true;
-    }
-  dests_node = dests_alloc->dests_node;
-  dests_ch = dests_alloc->dests_ch;
-
-  /* Initialize transition table.  */
-  state->word_trtable = state->trtable = NULL;
-
-  /* At first, group all nodes belonging to 'state' into several
-     destinations.  */
-  ndests = group_nodes_into_DFAstates (dfa, state, dests_node, dests_ch);
-  if (BE (! REG_VALID_NONZERO_INDEX (ndests), 0))
-    {
-      if (dests_node_malloced)
-	free (dests_alloc);
-      /* Return false in case of an error, true otherwise.  */
-      if (ndests == 0)
-	{
-	  state->trtable = (re_dfastate_t **)
-	    calloc (sizeof (re_dfastate_t *), SBC_MAX);
-          if (BE (state->trtable == NULL, 0))
-            return false;
-	  return true;
-	}
-      return false;
-    }
-
-  err = re_node_set_alloc (&follows, ndests + 1);
-  if (BE (err != REG_NOERROR, 0))
-    goto out_free;
-
-  /* Avoid arithmetic overflow in size calculation.  */
-  if (BE ((((SIZE_MAX - (sizeof (re_node_set) + sizeof (bitset_t)) * SBC_MAX)
-	    / (3 * sizeof (re_dfastate_t *)))
-	   < ndests),
-	  0))
-    goto out_free;
-
-  if (__libc_use_alloca ((sizeof (re_node_set) + sizeof (bitset_t)) * SBC_MAX
-			 + ndests * 3 * sizeof (re_dfastate_t *)))
-    dest_states = (re_dfastate_t **)
-      alloca (ndests * 3 * sizeof (re_dfastate_t *));
-  else
-    {
-      dest_states = (re_dfastate_t **)
-	malloc (ndests * 3 * sizeof (re_dfastate_t *));
-      if (BE (dest_states == NULL, 0))
-	{
-out_free:
-	  if (dest_states_malloced)
-	    free (dest_states);
-	  re_node_set_free (&follows);
-	  for (i = 0; i < ndests; ++i)
-	    re_node_set_free (dests_node + i);
-	  if (dests_node_malloced)
-	    free (dests_alloc);
-	  return false;
-	}
-      dest_states_malloced = true;
-    }
-  dest_states_word = dest_states + ndests;
-  dest_states_nl = dest_states_word + ndests;
-  bitset_empty (acceptable);
-
-  /* Then build the states for all destinations.  */
-  for (i = 0; i < ndests; ++i)
-    {
-      Idx next_node;
-      re_node_set_empty (&follows);
-      /* Merge the follows of this destination states.  */
-      for (j = 0; j < dests_node[i].nelem; ++j)
-	{
-	  next_node = dfa->nexts[dests_node[i].elems[j]];
-	  if (next_node != REG_MISSING)
-	    {
-	      err = re_node_set_merge (&follows, dfa->eclosures + next_node);
-	      if (BE (err != REG_NOERROR, 0))
-		goto out_free;
-	    }
-	}
-      dest_states[i] = re_acquire_state_context (&err, dfa, &follows, 0);
-      if (BE (dest_states[i] == NULL && err != REG_NOERROR, 0))
-	goto out_free;
-      /* If the new state has context constraint,
-	 build appropriate states for these contexts.  */
-      if (dest_states[i]->has_constraint)
-	{
-	  dest_states_word[i] = re_acquire_state_context (&err, dfa, &follows,
-							  CONTEXT_WORD);
-	  if (BE (dest_states_word[i] == NULL && err != REG_NOERROR, 0))
-	    goto out_free;
-
-	  if (dest_states[i] != dest_states_word[i] && dfa->mb_cur_max > 1)
-	    need_word_trtable = true;
-
-	  dest_states_nl[i] = re_acquire_state_context (&err, dfa, &follows,
-							CONTEXT_NEWLINE);
-	  if (BE (dest_states_nl[i] == NULL && err != REG_NOERROR, 0))
-	    goto out_free;
-	}
-      else
-	{
-	  dest_states_word[i] = dest_states[i];
-	  dest_states_nl[i] = dest_states[i];
-	}
-      bitset_merge (acceptable, dests_ch[i]);
-    }
-
-  if (!BE (need_word_trtable, 0))
-    {
-      /* We don't care about whether the following character is a word
-	 character, or we are in a single-byte character set so we can
-	 discern by looking at the character code: allocate a
-	 256-entry transition table.  */
-      trtable = state->trtable =
-	(re_dfastate_t **) calloc (sizeof (re_dfastate_t *), SBC_MAX);
-      if (BE (trtable == NULL, 0))
-	goto out_free;
-
-      /* For all characters ch...:  */
-      for (i = 0; i < BITSET_WORDS; ++i)
-	for (ch = i * BITSET_WORD_BITS, elem = acceptable[i], mask = 1;
-	     elem;
-	     mask <<= 1, elem >>= 1, ++ch)
-	  if (BE (elem & 1, 0))
-	    {
-	      /* There must be exactly one destination which accepts
-		 character ch.  See group_nodes_into_DFAstates.  */
-	      for (j = 0; (dests_ch[j][i] & mask) == 0; ++j)
-		;
-
-	      /* j-th destination accepts the word character ch.  */
-	      if (dfa->word_char[i] & mask)
-		trtable[ch] = dest_states_word[j];
-	      else
-		trtable[ch] = dest_states[j];
-	    }
-    }
-  else
-    {
-      /* We care about whether the following character is a word
-	 character, and we are in a multi-byte character set: discern
-	 by looking at the character code: build two 256-entry
-	 transition tables, one starting at trtable[0] and one
-	 starting at trtable[SBC_MAX].  */
-      trtable = state->word_trtable =
-	(re_dfastate_t **) calloc (sizeof (re_dfastate_t *), 2 * SBC_MAX);
-      if (BE (trtable == NULL, 0))
-	goto out_free;
-
-      /* For all characters ch...:  */
-      for (i = 0; i < BITSET_WORDS; ++i)
-	for (ch = i * BITSET_WORD_BITS, elem = acceptable[i], mask = 1;
-	     elem;
-	     mask <<= 1, elem >>= 1, ++ch)
-	  if (BE (elem & 1, 0))
-	    {
-	      /* There must be exactly one destination which accepts
-		 character ch.  See group_nodes_into_DFAstates.  */
-	      for (j = 0; (dests_ch[j][i] & mask) == 0; ++j)
-		;
-
-	      /* j-th destination accepts the word character ch.  */
-	      trtable[ch] = dest_states[j];
-	      trtable[ch + SBC_MAX] = dest_states_word[j];
-	    }
-    }
-
-  /* new line */
-  if (bitset_contain (acceptable, NEWLINE_CHAR))
-    {
-      /* The current state accepts newline character.  */
-      for (j = 0; j < ndests; ++j)
-	if (bitset_contain (dests_ch[j], NEWLINE_CHAR))
-	  {
-	    /* k-th destination accepts newline character.  */
-	    trtable[NEWLINE_CHAR] = dest_states_nl[j];
-	    if (need_word_trtable)
-	      trtable[NEWLINE_CHAR + SBC_MAX] = dest_states_nl[j];
-	    /* There must be only one destination which accepts
-	       newline.  See group_nodes_into_DFAstates.  */
-	    break;
-	  }
-    }
-
-  if (dest_states_malloced)
-    free (dest_states);
-
-  re_node_set_free (&follows);
-  for (i = 0; i < ndests; ++i)
-    re_node_set_free (dests_node + i);
-
-  if (dests_node_malloced)
-    free (dests_alloc);
-
-  return true;
-}
-
-/* Group all nodes belonging to STATE into several destinations.
-   Then for all destinations, set the nodes belonging to the destination
-   to DESTS_NODE[i] and set the characters accepted by the destination
-   to DEST_CH[i].  This function return the number of destinations.  */
-
-static Idx
-internal_function
-group_nodes_into_DFAstates (const re_dfa_t *dfa, const re_dfastate_t *state,
-			    re_node_set *dests_node, bitset_t *dests_ch)
-{
-  reg_errcode_t err;
-  bool ok;
-  Idx i, j, k;
-  Idx ndests; /* Number of the destinations from 'state'.  */
-  bitset_t accepts; /* Characters a node can accept.  */
-  const re_node_set *cur_nodes = &state->nodes;
-  bitset_empty (accepts);
-  ndests = 0;
-
-  /* For all the nodes belonging to 'state',  */
-  for (i = 0; i < cur_nodes->nelem; ++i)
-    {
-      re_token_t *node = &dfa->nodes[cur_nodes->elems[i]];
-      re_token_type_t type = node->type;
-      unsigned int constraint = node->constraint;
-
-      /* Enumerate all single byte character this node can accept.  */
-      if (type == CHARACTER)
-	bitset_set (accepts, node->opr.c);
-      else if (type == SIMPLE_BRACKET)
-	{
-	  bitset_merge (accepts, node->opr.sbcset);
-	}
-      else if (type == OP_PERIOD)
-	{
-#ifdef RE_ENABLE_I18N
-	  if (dfa->mb_cur_max > 1)
-	    bitset_merge (accepts, dfa->sb_char);
-	  else
-#endif
-	    bitset_set_all (accepts);
-	  if (!(dfa->syntax & RE_DOT_NEWLINE))
-	    bitset_clear (accepts, '\n');
-	  if (dfa->syntax & RE_DOT_NOT_NULL)
-	    bitset_clear (accepts, '\0');
-	}
-#ifdef RE_ENABLE_I18N
-      else if (type == OP_UTF8_PERIOD)
-	{
-	  if (ASCII_CHARS % BITSET_WORD_BITS == 0)
-	    memset (accepts, -1, ASCII_CHARS / CHAR_BIT);
-	  else
-	    bitset_merge (accepts, utf8_sb_map);
-	  if (!(dfa->syntax & RE_DOT_NEWLINE))
-	    bitset_clear (accepts, '\n');
-	  if (dfa->syntax & RE_DOT_NOT_NULL)
-	    bitset_clear (accepts, '\0');
-	}
-#endif
-      else
-	continue;
-
-      /* Check the 'accepts' and sift the characters which are not
-	 match it the context.  */
-      if (constraint)
-	{
-	  if (constraint & NEXT_NEWLINE_CONSTRAINT)
-	    {
-	      bool accepts_newline = bitset_contain (accepts, NEWLINE_CHAR);
-	      bitset_empty (accepts);
-	      if (accepts_newline)
-		bitset_set (accepts, NEWLINE_CHAR);
-	      else
-		continue;
-	    }
-	  if (constraint & NEXT_ENDBUF_CONSTRAINT)
-	    {
-	      bitset_empty (accepts);
-	      continue;
-	    }
-
-	  if (constraint & NEXT_WORD_CONSTRAINT)
-	    {
-	      bitset_word_t any_set = 0;
-	      if (type == CHARACTER && !node->word_char)
-		{
-		  bitset_empty (accepts);
-		  continue;
-		}
-#ifdef RE_ENABLE_I18N
-	      if (dfa->mb_cur_max > 1)
-		for (j = 0; j < BITSET_WORDS; ++j)
-		  any_set |= (accepts[j] &= (dfa->word_char[j] | ~dfa->sb_char[j]));
-	      else
-#endif
-		for (j = 0; j < BITSET_WORDS; ++j)
-		  any_set |= (accepts[j] &= dfa->word_char[j]);
-	      if (!any_set)
-		continue;
-	    }
-	  if (constraint & NEXT_NOTWORD_CONSTRAINT)
-	    {
-	      bitset_word_t any_set = 0;
-	      if (type == CHARACTER && node->word_char)
-		{
-		  bitset_empty (accepts);
-		  continue;
-		}
-#ifdef RE_ENABLE_I18N
-	      if (dfa->mb_cur_max > 1)
-		for (j = 0; j < BITSET_WORDS; ++j)
-		  any_set |= (accepts[j] &= ~(dfa->word_char[j] & dfa->sb_char[j]));
-	      else
-#endif
-		for (j = 0; j < BITSET_WORDS; ++j)
-		  any_set |= (accepts[j] &= ~dfa->word_char[j]);
-	      if (!any_set)
-		continue;
-	    }
-	}
-
-      /* Then divide 'accepts' into DFA states, or create a new
-	 state.  Above, we make sure that accepts is not empty.  */
-      for (j = 0; j < ndests; ++j)
-	{
-	  bitset_t intersec; /* Intersection sets, see below.  */
-	  bitset_t remains;
-	  /* Flags, see below.  */
-	  bitset_word_t has_intersec, not_subset, not_consumed;
-
-	  /* Optimization, skip if this state doesn't accept the character.  */
-	  if (type == CHARACTER && !bitset_contain (dests_ch[j], node->opr.c))
-	    continue;
-
-	  /* Enumerate the intersection set of this state and 'accepts'.  */
-	  has_intersec = 0;
-	  for (k = 0; k < BITSET_WORDS; ++k)
-	    has_intersec |= intersec[k] = accepts[k] & dests_ch[j][k];
-	  /* And skip if the intersection set is empty.  */
-	  if (!has_intersec)
-	    continue;
-
-	  /* Then check if this state is a subset of 'accepts'.  */
-	  not_subset = not_consumed = 0;
-	  for (k = 0; k < BITSET_WORDS; ++k)
-	    {
-	      not_subset |= remains[k] = ~accepts[k] & dests_ch[j][k];
-	      not_consumed |= accepts[k] = accepts[k] & ~dests_ch[j][k];
-	    }
-
-	  /* If this state isn't a subset of 'accepts', create a
-	     new group state, which has the 'remains'. */
-	  if (not_subset)
-	    {
-	      bitset_copy (dests_ch[ndests], remains);
-	      bitset_copy (dests_ch[j], intersec);
-	      err = re_node_set_init_copy (dests_node + ndests, &dests_node[j]);
-	      if (BE (err != REG_NOERROR, 0))
-		goto error_return;
-	      ++ndests;
-	    }
-
-	  /* Put the position in the current group. */
-	  ok = re_node_set_insert (&dests_node[j], cur_nodes->elems[i]);
-	  if (BE (! ok, 0))
-	    goto error_return;
-
-	  /* If all characters are consumed, go to next node. */
-	  if (!not_consumed)
-	    break;
-	}
-      /* Some characters remain, create a new group. */
-      if (j == ndests)
-	{
-	  bitset_copy (dests_ch[ndests], accepts);
-	  err = re_node_set_init_1 (dests_node + ndests, cur_nodes->elems[i]);
-	  if (BE (err != REG_NOERROR, 0))
-	    goto error_return;
-	  ++ndests;
-	  bitset_empty (accepts);
-	}
-    }
-  return ndests;
- error_return:
-  for (j = 0; j < ndests; ++j)
-    re_node_set_free (dests_node + j);
-  return REG_MISSING;
-}
-
-#ifdef RE_ENABLE_I18N
-/* Check how many bytes the node 'dfa->nodes[node_idx]' accepts.
-   Return the number of the bytes the node accepts.
-   STR_IDX is the current index of the input string.
-
-   This function handles the nodes which can accept one character, or
-   one collating element like '.', '[a-z]', opposite to the other nodes
-   can only accept one byte.  */
-
-static int
-internal_function
-check_node_accept_bytes (const re_dfa_t *dfa, Idx node_idx,
-			 const re_string_t *input, Idx str_idx)
-{
-  const re_token_t *node = dfa->nodes + node_idx;
-  int char_len, elem_len;
-  Idx i;
-
-  if (BE (node->type == OP_UTF8_PERIOD, 0))
-    {
-      unsigned char c = re_string_byte_at (input, str_idx), d;
-      if (BE (c < 0xc2, 1))
-	return 0;
-
-      if (str_idx + 2 > input->len)
-	return 0;
-
-      d = re_string_byte_at (input, str_idx + 1);
-      if (c < 0xe0)
-	return (d < 0x80 || d > 0xbf) ? 0 : 2;
-      else if (c < 0xf0)
-	{
-	  char_len = 3;
-	  if (c == 0xe0 && d < 0xa0)
-	    return 0;
-	}
-      else if (c < 0xf8)
-	{
-	  char_len = 4;
-	  if (c == 0xf0 && d < 0x90)
-	    return 0;
-	}
-      else if (c < 0xfc)
-	{
-	  char_len = 5;
-	  if (c == 0xf8 && d < 0x88)
-	    return 0;
-	}
-      else if (c < 0xfe)
-	{
-	  char_len = 6;
-	  if (c == 0xfc && d < 0x84)
-	    return 0;
-	}
-      else
-	return 0;
-
-      if (str_idx + char_len > input->len)
-	return 0;
-
-      for (i = 1; i < char_len; ++i)
-	{
-	  d = re_string_byte_at (input, str_idx + i);
-	  if (d < 0x80 || d > 0xbf)
-	    return 0;
-	}
-      return char_len;
-    }
-
-  char_len = re_string_char_size_at (input, str_idx);
-  if (node->type == OP_PERIOD)
-    {
-      if (char_len <= 1)
-	return 0;
-      /* FIXME: I don't think this if is needed, as both '\n'
-	 and '\0' are char_len == 1.  */
-      /* '.' accepts any one character except the following two cases.  */
-      if ((!(dfa->syntax & RE_DOT_NEWLINE) &&
-	   re_string_byte_at (input, str_idx) == '\n') ||
-	  ((dfa->syntax & RE_DOT_NOT_NULL) &&
-	   re_string_byte_at (input, str_idx) == '\0'))
-	return 0;
-      return char_len;
-    }
-
-  elem_len = re_string_elem_size_at (input, str_idx);
-  if ((elem_len <= 1 && char_len <= 1) || char_len == 0)
-    return 0;
-
-  if (node->type == COMPLEX_BRACKET)
-    {
-      const re_charset_t *cset = node->opr.mbcset;
-# ifdef _LIBC
-      const unsigned char *pin
-	= ((const unsigned char *) re_string_get_buffer (input) + str_idx);
-      Idx j;
-      uint32_t nrules;
-# endif /* _LIBC */
-      int match_len = 0;
-      wchar_t wc = ((cset->nranges || cset->nchar_classes || cset->nmbchars)
-		    ? re_string_wchar_at (input, str_idx) : 0);
-
-      /* match with multibyte character?  */
-      for (i = 0; i < cset->nmbchars; ++i)
-	if (wc == cset->mbchars[i])
-	  {
-	    match_len = char_len;
-	    goto check_node_accept_bytes_match;
-	  }
-      /* match with character_class?  */
-      for (i = 0; i < cset->nchar_classes; ++i)
-	{
-	  wctype_t wt = cset->char_classes[i];
-	  if (__iswctype (wc, wt))
-	    {
-	      match_len = char_len;
-	      goto check_node_accept_bytes_match;
-	    }
-	}
-
-# ifdef _LIBC
-      nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES);
-      if (nrules != 0)
-	{
-	  unsigned int in_collseq = 0;
-	  const int32_t *table, *indirect;
-	  const unsigned char *weights, *extra;
-	  const char *collseqwc;
-	  /* This #include defines a local function!  */
-#  include <locale/weight.h>
-
-	  /* match with collating_symbol?  */
-	  if (cset->ncoll_syms)
-	    extra = (const unsigned char *)
-	      _NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB);
-	  for (i = 0; i < cset->ncoll_syms; ++i)
-	    {
-	      const unsigned char *coll_sym = extra + cset->coll_syms[i];
-	      /* Compare the length of input collating element and
-		 the length of current collating element.  */
-	      if (*coll_sym != elem_len)
-		continue;
-	      /* Compare each bytes.  */
-	      for (j = 0; j < *coll_sym; j++)
-		if (pin[j] != coll_sym[1 + j])
-		  break;
-	      if (j == *coll_sym)
-		{
-		  /* Match if every bytes is equal.  */
-		  match_len = j;
-		  goto check_node_accept_bytes_match;
-		}
-	    }
-
-	  if (cset->nranges)
-	    {
-	      if (elem_len <= char_len)
-		{
-		  collseqwc = _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQWC);
-		  in_collseq = __collseq_table_lookup (collseqwc, wc);
-		}
-	      else
-		in_collseq = find_collation_sequence_value (pin, elem_len);
-	    }
-	  /* match with range expression?  */
-	  /* FIXME: Implement rational ranges here, too.  */
-	  for (i = 0; i < cset->nranges; ++i)
-	    if (cset->range_starts[i] <= in_collseq
-		&& in_collseq <= cset->range_ends[i])
-	      {
-		match_len = elem_len;
-		goto check_node_accept_bytes_match;
-	      }
-
-	  /* match with equivalence_class?  */
-	  if (cset->nequiv_classes)
-	    {
-	      const unsigned char *cp = pin;
-	      table = (const int32_t *)
-		_NL_CURRENT (LC_COLLATE, _NL_COLLATE_TABLEMB);
-	      weights = (const unsigned char *)
-		_NL_CURRENT (LC_COLLATE, _NL_COLLATE_WEIGHTMB);
-	      extra = (const unsigned char *)
-		_NL_CURRENT (LC_COLLATE, _NL_COLLATE_EXTRAMB);
-	      indirect = (const int32_t *)
-		_NL_CURRENT (LC_COLLATE, _NL_COLLATE_INDIRECTMB);
-	      int32_t idx = findidx (&cp, elem_len);
-	      if (idx > 0)
-		for (i = 0; i < cset->nequiv_classes; ++i)
-		  {
-		    int32_t equiv_class_idx = cset->equiv_classes[i];
-		    size_t weight_len = weights[idx & 0xffffff];
-		    if (weight_len == weights[equiv_class_idx & 0xffffff]
-			&& (idx >> 24) == (equiv_class_idx >> 24))
-		      {
-			Idx cnt = 0;
-
-			idx &= 0xffffff;
-			equiv_class_idx &= 0xffffff;
-
-			while (cnt <= weight_len
-			       && (weights[equiv_class_idx + 1 + cnt]
-				   == weights[idx + 1 + cnt]))
-			  ++cnt;
-			if (cnt > weight_len)
-			  {
-			    match_len = elem_len;
-			    goto check_node_accept_bytes_match;
-			  }
-		      }
-		  }
-	    }
-	}
-      else
-# endif /* _LIBC */
-	{
-	  /* match with range expression?  */
-	  for (i = 0; i < cset->nranges; ++i)
-	    {
-	      if (cset->range_starts[i] <= wc && wc <= cset->range_ends[i])
-		{
-		  match_len = char_len;
-		  goto check_node_accept_bytes_match;
-		}
-	    }
-	}
-    check_node_accept_bytes_match:
-      if (!cset->non_match)
-	return match_len;
-      else
-	{
-	  if (match_len > 0)
-	    return 0;
-	  else
-	    return (elem_len > char_len) ? elem_len : char_len;
-	}
-    }
-  return 0;
-}
-
-# ifdef _LIBC
-static unsigned int
-internal_function
-find_collation_sequence_value (const unsigned char *mbs, size_t mbs_len)
-{
-  uint32_t nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES);
-  if (nrules == 0)
-    {
-      if (mbs_len == 1)
-	{
-	  /* No valid character.  Match it as a single byte character.  */
-	  const unsigned char *collseq = (const unsigned char *)
-	    _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQMB);
-	  return collseq[mbs[0]];
-	}
-      return UINT_MAX;
-    }
-  else
-    {
-      int32_t idx;
-      const unsigned char *extra = (const unsigned char *)
-	_NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB);
-      int32_t extrasize = (const unsigned char *)
-	_NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB + 1) - extra;
-
-      for (idx = 0; idx < extrasize;)
-	{
-	  int mbs_cnt;
-	  bool found = false;
-	  int32_t elem_mbs_len;
-	  /* Skip the name of collating element name.  */
-	  idx = idx + extra[idx] + 1;
-	  elem_mbs_len = extra[idx++];
-	  if (mbs_len == elem_mbs_len)
-	    {
-	      for (mbs_cnt = 0; mbs_cnt < elem_mbs_len; ++mbs_cnt)
-		if (extra[idx + mbs_cnt] != mbs[mbs_cnt])
-		  break;
-	      if (mbs_cnt == elem_mbs_len)
-		/* Found the entry.  */
-		found = true;
-	    }
-	  /* Skip the byte sequence of the collating element.  */
-	  idx += elem_mbs_len;
-	  /* Adjust for the alignment.  */
-	  idx = (idx + 3) & ~3;
-	  /* Skip the collation sequence value.  */
-	  idx += sizeof (uint32_t);
-	  /* Skip the wide char sequence of the collating element.  */
-	  idx = idx + sizeof (uint32_t) * (*(int32_t *) (extra + idx) + 1);
-	  /* If we found the entry, return the sequence value.  */
-	  if (found)
-	    return *(uint32_t *) (extra + idx);
-	  /* Skip the collation sequence value.  */
-	  idx += sizeof (uint32_t);
-	}
-      return UINT_MAX;
-    }
-}
-# endif /* _LIBC */
-#endif /* RE_ENABLE_I18N */
-
-/* Check whether the node accepts the byte which is IDX-th
-   byte of the INPUT.  */
-
-static bool
-internal_function
-check_node_accept (const re_match_context_t *mctx, const re_token_t *node,
-		   Idx idx)
-{
-  unsigned char ch;
-  ch = re_string_byte_at (&mctx->input, idx);
-  switch (node->type)
-    {
-    case CHARACTER:
-      if (node->opr.c != ch)
-        return false;
-      break;
-
-    case SIMPLE_BRACKET:
-      if (!bitset_contain (node->opr.sbcset, ch))
-        return false;
-      break;
-
-#ifdef RE_ENABLE_I18N
-    case OP_UTF8_PERIOD:
-      if (ch >= ASCII_CHARS)
-        return false;
-      /* FALLTHROUGH */
-#endif
-    case OP_PERIOD:
-      if ((ch == '\n' && !(mctx->dfa->syntax & RE_DOT_NEWLINE))
-	  || (ch == '\0' && (mctx->dfa->syntax & RE_DOT_NOT_NULL)))
-	return false;
-      break;
-
-    default:
-      return false;
-    }
-
-  if (node->constraint)
-    {
-      /* The node has constraints.  Check whether the current context
-	 satisfies the constraints.  */
-      unsigned int context = re_string_context_at (&mctx->input, idx,
-						   mctx->eflags);
-      if (NOT_SATISFY_NEXT_CONSTRAINT (node->constraint, context))
-	return false;
-    }
-
-  return true;
-}
-
-/* Extend the buffers, if the buffers have run out.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-extend_buffers (re_match_context_t *mctx, int min_len)
-{
-  reg_errcode_t ret;
-  re_string_t *pstr = &mctx->input;
-
-  /* Avoid overflow.  */
-  if (BE (MIN (IDX_MAX, SIZE_MAX / sizeof (re_dfastate_t *)) / 2
-          <= pstr->bufs_len, 0))
-    return REG_ESPACE;
-
-  /* Double the lengths of the buffers, but allocate at least MIN_LEN.  */
-  ret = re_string_realloc_buffers (pstr,
-				   MAX (min_len,
-					MIN (pstr->len, pstr->bufs_len * 2)));
-  if (BE (ret != REG_NOERROR, 0))
-    return ret;
-
-  if (mctx->state_log != NULL)
-    {
-      /* And double the length of state_log.  */
-      /* XXX We have no indication of the size of this buffer.  If this
-	 allocation fail we have no indication that the state_log array
-	 does not have the right size.  */
-      re_dfastate_t **new_array = re_realloc (mctx->state_log, re_dfastate_t *,
-					      pstr->bufs_len + 1);
-      if (BE (new_array == NULL, 0))
-	return REG_ESPACE;
-      mctx->state_log = new_array;
-    }
-
-  /* Then reconstruct the buffers.  */
-  if (pstr->icase)
-    {
-#ifdef RE_ENABLE_I18N
-      if (pstr->mb_cur_max > 1)
-	{
-	  ret = build_wcs_upper_buffer (pstr);
-	  if (BE (ret != REG_NOERROR, 0))
-	    return ret;
-	}
-      else
-#endif /* RE_ENABLE_I18N  */
-	build_upper_buffer (pstr);
-    }
-  else
-    {
-#ifdef RE_ENABLE_I18N
-      if (pstr->mb_cur_max > 1)
-	build_wcs_buffer (pstr);
-      else
-#endif /* RE_ENABLE_I18N  */
-	{
-	  if (pstr->trans != NULL)
-	    re_string_translate_buffer (pstr);
-	}
-    }
-  return REG_NOERROR;
-}
-
-
-/* Functions for matching context.  */
-
-/* Initialize MCTX.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-match_ctx_init (re_match_context_t *mctx, int eflags, Idx n)
-{
-  mctx->eflags = eflags;
-  mctx->match_last = REG_MISSING;
-  if (n > 0)
-    {
-      /* Avoid overflow.  */
-      size_t max_object_size =
-	MAX (sizeof (struct re_backref_cache_entry),
-	     sizeof (re_sub_match_top_t *));
-      if (BE (MIN (IDX_MAX, SIZE_MAX / max_object_size) < n, 0))
-	return REG_ESPACE;
-
-      mctx->bkref_ents = re_malloc (struct re_backref_cache_entry, n);
-      mctx->sub_tops = re_malloc (re_sub_match_top_t *, n);
-      if (BE (mctx->bkref_ents == NULL || mctx->sub_tops == NULL, 0))
-	return REG_ESPACE;
-    }
-  /* Already zero-ed by the caller.
-     else
-       mctx->bkref_ents = NULL;
-     mctx->nbkref_ents = 0;
-     mctx->nsub_tops = 0;  */
-  mctx->abkref_ents = n;
-  mctx->max_mb_elem_len = 1;
-  mctx->asub_tops = n;
-  return REG_NOERROR;
-}
-
-/* Clean the entries which depend on the current input in MCTX.
-   This function must be invoked when the matcher changes the start index
-   of the input, or changes the input string.  */
-
-static void
-internal_function
-match_ctx_clean (re_match_context_t *mctx)
-{
-  Idx st_idx;
-  for (st_idx = 0; st_idx < mctx->nsub_tops; ++st_idx)
-    {
-      Idx sl_idx;
-      re_sub_match_top_t *top = mctx->sub_tops[st_idx];
-      for (sl_idx = 0; sl_idx < top->nlasts; ++sl_idx)
-	{
-	  re_sub_match_last_t *last = top->lasts[sl_idx];
-	  re_free (last->path.array);
-	  re_free (last);
-	}
-      re_free (top->lasts);
-      if (top->path)
-	{
-	  re_free (top->path->array);
-	  re_free (top->path);
-	}
-      free (top);
-    }
-
-  mctx->nsub_tops = 0;
-  mctx->nbkref_ents = 0;
-}
-
-/* Free all the memory associated with MCTX.  */
-
-static void
-internal_function
-match_ctx_free (re_match_context_t *mctx)
-{
-  /* First, free all the memory associated with MCTX->SUB_TOPS.  */
-  match_ctx_clean (mctx);
-  re_free (mctx->sub_tops);
-  re_free (mctx->bkref_ents);
-}
-
-/* Add a new backreference entry to MCTX.
-   Note that we assume that caller never call this function with duplicate
-   entry, and call with STR_IDX which isn't smaller than any existing entry.
-*/
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-match_ctx_add_entry (re_match_context_t *mctx, Idx node, Idx str_idx, Idx from,
-		     Idx to)
-{
-  if (mctx->nbkref_ents >= mctx->abkref_ents)
-    {
-      struct re_backref_cache_entry* new_entry;
-      new_entry = re_realloc (mctx->bkref_ents, struct re_backref_cache_entry,
-			      mctx->abkref_ents * 2);
-      if (BE (new_entry == NULL, 0))
-	{
-	  re_free (mctx->bkref_ents);
-	  return REG_ESPACE;
-	}
-      mctx->bkref_ents = new_entry;
-      memset (mctx->bkref_ents + mctx->nbkref_ents, '\0',
-	      sizeof (struct re_backref_cache_entry) * mctx->abkref_ents);
-      mctx->abkref_ents *= 2;
-    }
-  if (mctx->nbkref_ents > 0
-      && mctx->bkref_ents[mctx->nbkref_ents - 1].str_idx == str_idx)
-    mctx->bkref_ents[mctx->nbkref_ents - 1].more = 1;
-
-  mctx->bkref_ents[mctx->nbkref_ents].node = node;
-  mctx->bkref_ents[mctx->nbkref_ents].str_idx = str_idx;
-  mctx->bkref_ents[mctx->nbkref_ents].subexp_from = from;
-  mctx->bkref_ents[mctx->nbkref_ents].subexp_to = to;
-
-  /* This is a cache that saves negative results of check_dst_limits_calc_pos.
-     If bit N is clear, means that this entry won't epsilon-transition to
-     an OP_OPEN_SUBEXP or OP_CLOSE_SUBEXP for the N+1-th subexpression.  If
-     it is set, check_dst_limits_calc_pos_1 will recurse and try to find one
-     such node.
-
-     A backreference does not epsilon-transition unless it is empty, so set
-     to all zeros if FROM != TO.  */
-  mctx->bkref_ents[mctx->nbkref_ents].eps_reachable_subexps_map
-    = (from == to ? -1 : 0);
-
-  mctx->bkref_ents[mctx->nbkref_ents++].more = 0;
-  if (mctx->max_mb_elem_len < to - from)
-    mctx->max_mb_elem_len = to - from;
-  return REG_NOERROR;
-}
-
-/* Return the first entry with the same str_idx, or REG_MISSING if none is
-   found.  Note that MCTX->BKREF_ENTS is already sorted by MCTX->STR_IDX.  */
-
-static Idx
-internal_function
-search_cur_bkref_entry (const re_match_context_t *mctx, Idx str_idx)
-{
-  Idx left, right, mid, last;
-  last = right = mctx->nbkref_ents;
-  for (left = 0; left < right;)
-    {
-      mid = (left + right) / 2;
-      if (mctx->bkref_ents[mid].str_idx < str_idx)
-	left = mid + 1;
-      else
-	right = mid;
-    }
-  if (left < last && mctx->bkref_ents[left].str_idx == str_idx)
-    return left;
-  else
-    return REG_MISSING;
-}
-
-/* Register the node NODE, whose type is OP_OPEN_SUBEXP, and which matches
-   at STR_IDX.  */
-
-static reg_errcode_t
-internal_function __attribute_warn_unused_result__
-match_ctx_add_subtop (re_match_context_t *mctx, Idx node, Idx str_idx)
-{
-#ifdef DEBUG
-  assert (mctx->sub_tops != NULL);
-  assert (mctx->asub_tops > 0);
-#endif
-  if (BE (mctx->nsub_tops == mctx->asub_tops, 0))
-    {
-      Idx new_asub_tops = mctx->asub_tops * 2;
-      re_sub_match_top_t **new_array = re_realloc (mctx->sub_tops,
-						   re_sub_match_top_t *,
-						   new_asub_tops);
-      if (BE (new_array == NULL, 0))
-	return REG_ESPACE;
-      mctx->sub_tops = new_array;
-      mctx->asub_tops = new_asub_tops;
-    }
-  mctx->sub_tops[mctx->nsub_tops] = calloc (1, sizeof (re_sub_match_top_t));
-  if (BE (mctx->sub_tops[mctx->nsub_tops] == NULL, 0))
-    return REG_ESPACE;
-  mctx->sub_tops[mctx->nsub_tops]->node = node;
-  mctx->sub_tops[mctx->nsub_tops++]->str_idx = str_idx;
-  return REG_NOERROR;
-}
-
-/* Register the node NODE, whose type is OP_CLOSE_SUBEXP, and which matches
-   at STR_IDX, whose corresponding OP_OPEN_SUBEXP is SUB_TOP.  */
-
-static re_sub_match_last_t *
-internal_function
-match_ctx_add_sublast (re_sub_match_top_t *subtop, Idx node, Idx str_idx)
-{
-  re_sub_match_last_t *new_entry;
-  if (BE (subtop->nlasts == subtop->alasts, 0))
-    {
-      Idx new_alasts = 2 * subtop->alasts + 1;
-      re_sub_match_last_t **new_array = re_realloc (subtop->lasts,
-						    re_sub_match_last_t *,
-						    new_alasts);
-      if (BE (new_array == NULL, 0))
-	return NULL;
-      subtop->lasts = new_array;
-      subtop->alasts = new_alasts;
-    }
-  new_entry = calloc (1, sizeof (re_sub_match_last_t));
-  if (BE (new_entry != NULL, 1))
-    {
-      subtop->lasts[subtop->nlasts] = new_entry;
-      new_entry->node = node;
-      new_entry->str_idx = str_idx;
-      ++subtop->nlasts;
-    }
-  return new_entry;
-}
-
-static void
-internal_function
-sift_ctx_init (re_sift_context_t *sctx, re_dfastate_t **sifted_sts,
-	       re_dfastate_t **limited_sts, Idx last_node, Idx last_str_idx)
-{
-  sctx->sifted_states = sifted_sts;
-  sctx->limited_states = limited_sts;
-  sctx->last_node = last_node;
-  sctx->last_str_idx = last_str_idx;
-  re_node_set_init_empty (&sctx->limits);
-}
diff --git a/contrib/tools/bison/lib/spawn_int.h b/contrib/tools/bison/lib/spawn_int.h
deleted file mode 100644
index f22a659fbe..0000000000
--- a/contrib/tools/bison/lib/spawn_int.h
+++ /dev/null
@@ -1,62 +0,0 @@
-/* Copyright (C) 2000, 2008-2013 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   This program is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-#include <sys/types.h>
-
-/* Data structure to contain the action information.  */
-struct __spawn_action
-{
-  enum
-  {
-    spawn_do_close,
-    spawn_do_dup2,
-    spawn_do_open
-  } tag;
-
-  union
-  {
-    struct
-    {
-      int fd;
-    } close_action;
-    struct
-    {
-      int fd;
-      int newfd;
-    } dup2_action;
-    struct
-    {
-      int fd;
-      const char *path;
-      int oflag;
-      mode_t mode;
-    } open_action;
-  } action;
-};
-
-#if !_LIBC
-# define __posix_spawn_file_actions_realloc gl_posix_spawn_file_actions_realloc
-#endif
-extern int __posix_spawn_file_actions_realloc (posix_spawn_file_actions_t *
-                                               file_actions);
-
-#if !_LIBC
-# define __spawni gl_posix_spawn_internal
-#endif
-extern int __spawni (pid_t *pid, const char *path,
-                     const posix_spawn_file_actions_t *file_actions,
-                     const posix_spawnattr_t *attrp, char *const argv[],
-                     char *const envp[], int use_path);
diff --git a/contrib/tools/bison/lib/spawni.c b/contrib/tools/bison/lib/spawni.c
deleted file mode 100644
index e2f7b45b60..0000000000
--- a/contrib/tools/bison/lib/spawni.c
+++ /dev/null
@@ -1,374 +0,0 @@
-/* Guts of POSIX spawn interface.  Generic POSIX.1 version.
-   Copyright (C) 2000-2006, 2008-2013 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   This program is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-#include <config.h>
-
-/* Specification.  */
-#include <spawn.h>
-#include "spawn_int.h"
-
-#include "palloca.h"
-#include <errno.h>
-
-#include <fcntl.h>
-#ifndef O_LARGEFILE
-# define O_LARGEFILE 0
-#endif
-
-#if _LIBC || HAVE_PATHS_H
-# include <paths.h>
-#else
-# define _PATH_BSHELL "/bin/sh"
-#endif
-
-#include <signal.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#if _LIBC
-# include <not-cancel.h>
-#else
-# define close_not_cancel close
-# define open_not_cancel open
-#endif
-
-#if _LIBC
-# include <local-setxid.h>
-#else
-# if !HAVE_SETEUID
-#  define seteuid(id) setresuid (-1, id, -1)
-# endif
-# if !HAVE_SETEGID
-#  define setegid(id) setresgid (-1, id, -1)
-# endif
-# define local_seteuid(id) seteuid (id)
-# define local_setegid(id) setegid (id)
-#endif
-
-#if _LIBC
-# define alloca __alloca
-# define execve __execve
-# define dup2 __dup2
-# define fork __fork
-# define getgid __getgid
-# define getuid __getuid
-# define sched_setparam __sched_setparam
-# define sched_setscheduler __sched_setscheduler
-# define setpgid __setpgid
-# define sigaction __sigaction
-# define sigismember __sigismember
-# define sigprocmask __sigprocmask
-# define strchrnul __strchrnul
-# define vfork __vfork
-#else
-# undef internal_function
-# define internal_function /* empty */
-#endif
-
-
-/* The Unix standard contains a long explanation of the way to signal
-   an error after the fork() was successful.  Since no new wait status
-   was wanted there is no way to signal an error using one of the
-   available methods.  The committee chose to signal an error by a
-   normal program exit with the exit code 127.  */
-#define SPAWN_ERROR     127
-
-
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
-
-/* Native Windows API.  */
-int
-__spawni (pid_t *pid, const char *file,
-          const posix_spawn_file_actions_t *file_actions,
-          const posix_spawnattr_t *attrp, char *const argv[],
-          char *const envp[], int use_path)
-{
-  /* Not yet implemented.  */
-  return ENOSYS;
-}
-
-#else
-
-
-/* The file is accessible but it is not an executable file.  Invoke
-   the shell to interpret it as a script.  */
-static void
-internal_function
-script_execute (const char *file, char *const argv[], char *const envp[])
-{
-  /* Count the arguments.  */
-  int argc = 0;
-  while (argv[argc++])
-    ;
-
-  /* Construct an argument list for the shell.  */
-  {
-    char **new_argv = (char **) alloca ((argc + 1) * sizeof (char *));
-    new_argv[0] = (char *) _PATH_BSHELL;
-    new_argv[1] = (char *) file;
-    while (argc > 1)
-      {
-        new_argv[argc] = argv[argc - 1];
-        --argc;
-      }
-
-    /* Execute the shell.  */
-    execve (new_argv[0], new_argv, envp);
-  }
-}
-
-
-/* Spawn a new process executing PATH with the attributes describes in *ATTRP.
-   Before running the process perform the actions described in FILE-ACTIONS. */
-int
-__spawni (pid_t *pid, const char *file,
-          const posix_spawn_file_actions_t *file_actions,
-          const posix_spawnattr_t *attrp, char *const argv[],
-          char *const envp[], int use_path)
-{
-  pid_t new_pid;
-  char *path, *p, *name;
-  size_t len;
-  size_t pathlen;
-
-  /* Do this once.  */
-  short int flags = attrp == NULL ? 0 : attrp->_flags;
-
-  /* Avoid gcc warning
-       "variable 'flags' might be clobbered by 'longjmp' or 'vfork'"  */
-  (void) &flags;
-
-  /* Generate the new process.  */
-#if HAVE_VFORK
-  if ((flags & POSIX_SPAWN_USEVFORK) != 0
-      /* If no major work is done, allow using vfork.  Note that we
-         might perform the path searching.  But this would be done by
-         a call to execvp(), too, and such a call must be OK according
-         to POSIX.  */
-      || ((flags & (POSIX_SPAWN_SETSIGMASK | POSIX_SPAWN_SETSIGDEF
-                    | POSIX_SPAWN_SETSCHEDPARAM | POSIX_SPAWN_SETSCHEDULER
-                    | POSIX_SPAWN_SETPGROUP | POSIX_SPAWN_RESETIDS)) == 0
-          && file_actions == NULL))
-    new_pid = vfork ();
-  else
-#endif
-    new_pid = fork ();
-
-  if (new_pid != 0)
-    {
-      if (new_pid < 0)
-        return errno;
-
-      /* The call was successful.  Store the PID if necessary.  */
-      if (pid != NULL)
-        *pid = new_pid;
-
-      return 0;
-    }
-
-  /* Set signal mask.  */
-  if ((flags & POSIX_SPAWN_SETSIGMASK) != 0
-      && sigprocmask (SIG_SETMASK, &attrp->_ss, NULL) != 0)
-    _exit (SPAWN_ERROR);
-
-  /* Set signal default action.  */
-  if ((flags & POSIX_SPAWN_SETSIGDEF) != 0)
-    {
-      /* We have to iterate over all signals.  This could possibly be
-         done better but it requires system specific solutions since
-         the sigset_t data type can be very different on different
-         architectures.  */
-      int sig;
-      struct sigaction sa;
-
-      memset (&sa, '\0', sizeof (sa));
-      sa.sa_handler = SIG_DFL;
-
-      for (sig = 1; sig <= NSIG; ++sig)
-        if (sigismember (&attrp->_sd, sig) != 0
-            && sigaction (sig, &sa, NULL) != 0)
-          _exit (SPAWN_ERROR);
-
-    }
-
-#if (_LIBC ? defined _POSIX_PRIORITY_SCHEDULING : HAVE_SCHED_SETPARAM && HAVE_SCHED_SETSCHEDULER)
-  /* Set the scheduling algorithm and parameters.  */
-  if ((flags & (POSIX_SPAWN_SETSCHEDPARAM | POSIX_SPAWN_SETSCHEDULER))
-      == POSIX_SPAWN_SETSCHEDPARAM)
-    {
-      if (sched_setparam (0, &attrp->_sp) == -1)
-        _exit (SPAWN_ERROR);
-    }
-  else if ((flags & POSIX_SPAWN_SETSCHEDULER) != 0)
-    {
-      if (sched_setscheduler (0, attrp->_policy,
-                              (flags & POSIX_SPAWN_SETSCHEDPARAM) != 0
-                              ? &attrp->_sp : NULL) == -1)
-        _exit (SPAWN_ERROR);
-    }
-#endif
-
-  /* Set the process group ID.  */
-  if ((flags & POSIX_SPAWN_SETPGROUP) != 0
-      && setpgid (0, attrp->_pgrp) != 0)
-    _exit (SPAWN_ERROR);
-
-  /* Set the effective user and group IDs.  */
-  if ((flags & POSIX_SPAWN_RESETIDS) != 0
-      && (local_seteuid (getuid ()) != 0
-          || local_setegid (getgid ()) != 0))
-    _exit (SPAWN_ERROR);
-
-  /* Execute the file actions.  */
-  if (file_actions != NULL)
-    {
-      int cnt;
-
-      for (cnt = 0; cnt < file_actions->_used; ++cnt)
-        {
-          struct __spawn_action *action = &file_actions->_actions[cnt];
-
-          switch (action->tag)
-            {
-            case spawn_do_close:
-              if (close_not_cancel (action->action.close_action.fd) != 0)
-                /* Signal the error.  */
-                _exit (SPAWN_ERROR);
-              break;
-
-            case spawn_do_open:
-              {
-                int new_fd = open_not_cancel (action->action.open_action.path,
-                                              action->action.open_action.oflag
-                                              | O_LARGEFILE,
-                                              action->action.open_action.mode);
-
-                if (new_fd == -1)
-                  /* The 'open' call failed.  */
-                  _exit (SPAWN_ERROR);
-
-                /* Make sure the desired file descriptor is used.  */
-                if (new_fd != action->action.open_action.fd)
-                  {
-                    if (dup2 (new_fd, action->action.open_action.fd)
-                        != action->action.open_action.fd)
-                      /* The 'dup2' call failed.  */
-                      _exit (SPAWN_ERROR);
-
-                    if (close_not_cancel (new_fd) != 0)
-                      /* The 'close' call failed.  */
-                      _exit (SPAWN_ERROR);
-                  }
-              }
-              break;
-
-            case spawn_do_dup2:
-              if (dup2 (action->action.dup2_action.fd,
-                        action->action.dup2_action.newfd)
-                  != action->action.dup2_action.newfd)
-                /* The 'dup2' call failed.  */
-                _exit (SPAWN_ERROR);
-              break;
-            }
-        }
-    }
-
-  if (! use_path || strchr (file, '/') != NULL)
-    {
-      /* The FILE parameter is actually a path.  */
-      execve (file, argv, envp);
-
-      if (errno == ENOEXEC)
-        script_execute (file, argv, envp);
-
-      /* Oh, oh.  'execve' returns.  This is bad.  */
-      _exit (SPAWN_ERROR);
-    }
-
-  /* We have to search for FILE on the path.  */
-  path = getenv ("PATH");
-  if (path == NULL)
-    {
-#if HAVE_CONFSTR
-      /* There is no 'PATH' in the environment.
-         The default search path is the current directory
-         followed by the path 'confstr' returns for '_CS_PATH'.  */
-      len = confstr (_CS_PATH, (char *) NULL, 0);
-      path = (char *) alloca (1 + len);
-      path[0] = ':';
-      (void) confstr (_CS_PATH, path + 1, len);
-#else
-      /* Pretend that the PATH contains only the current directory.  */
-      path = "";
-#endif
-    }
-
-  len = strlen (file) + 1;
-  pathlen = strlen (path);
-  name = alloca (pathlen + len + 1);
-  /* Copy the file name at the top.  */
-  name = (char *) memcpy (name + pathlen + 1, file, len);
-  /* And add the slash.  */
-  *--name = '/';
-
-  p = path;
-  do
-    {
-      char *startp;
-
-      path = p;
-      p = strchrnul (path, ':');
-
-      if (p == path)
-        /* Two adjacent colons, or a colon at the beginning or the end
-           of 'PATH' means to search the current directory.  */
-        startp = name + 1;
-      else
-        startp = (char *) memcpy (name - (p - path), path, p - path);
-
-      /* Try to execute this name.  If it works, execv will not return.  */
-      execve (startp, argv, envp);
-
-      if (errno == ENOEXEC)
-        script_execute (startp, argv, envp);
-
-      switch (errno)
-        {
-        case EACCES:
-        case ENOENT:
-        case ESTALE:
-        case ENOTDIR:
-          /* Those errors indicate the file is missing or not executable
-             by us, in which case we want to just try the next path
-             directory.  */
-          break;
-
-        default:
-          /* Some other error means we found an executable file, but
-             something went wrong executing it; return the error to our
-             caller.  */
-          _exit (SPAWN_ERROR);
-        }
-    }
-  while (*p++ != '\0');
-
-  /* Return with an error.  */
-  _exit (SPAWN_ERROR);
-}
-
-#endif
diff --git a/contrib/tools/bison/lib/spawnp.c b/contrib/tools/bison/lib/spawnp.c
deleted file mode 100644
index 8bc5f99aca..0000000000
--- a/contrib/tools/bison/lib/spawnp.c
+++ /dev/null
@@ -1,33 +0,0 @@
-/* Copyright (C) 2000, 2009-2013 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   This program is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-#include <config.h>
-
-/* Specification.  */
-#include <spawn.h>
-
-#include "spawn_int.h"
-
-/* Spawn a new process executing FILE with the attributes describes in *ATTRP.
-   Before running the process perform the actions described in FILE-ACTIONS. */
-int
-posix_spawnp (pid_t *pid, const char *file,
-              const posix_spawn_file_actions_t *file_actions,
-              const posix_spawnattr_t *attrp, char *const argv[],
-              char *const envp[])
-{
-  return __spawni (pid, file, file_actions, attrp, argv, envp, 1);
-}
diff --git a/contrib/tools/bison/lib/tmpdir.c b/contrib/tools/bison/lib/tmpdir.c
deleted file mode 100644
index 1b3fb023a0..0000000000
--- a/contrib/tools/bison/lib/tmpdir.c
+++ /dev/null
@@ -1,159 +0,0 @@
-/* Copyright (C) 1999, 2001-2002, 2006, 2009-2013 Free Software Foundation,
-   Inc.
-   This file is part of the GNU C Library.
-
-   This program is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-/* Extracted from sysdeps/posix/tempname.c.  */
-
-#include <config.h>
-
-/* Specification.  */
-#include "tmpdir.h"
-
-#include <stdbool.h>
-#include "stdlib--.h"
-#include <string.h>
-
-#include <errno.h>
-#ifndef __set_errno
-# define __set_errno(Val) errno = (Val)
-#endif
-
-#include <stdio.h>
-#ifndef P_tmpdir
-# ifdef _P_tmpdir /* native Windows */
-#  define P_tmpdir _P_tmpdir
-# else
-#  define P_tmpdir "/tmp"
-# endif
-#endif
-
-#include <sys/stat.h>
-
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
-# define WIN32_LEAN_AND_MEAN  /* avoid including junk */
-# include <windows.h>
-#endif
-
-#include "pathmax.h"
-
-#if _LIBC
-# define struct_stat64 struct stat64
-#else
-# define struct_stat64 struct stat
-# define __libc_secure_getenv secure_getenv
-# define __xstat64(version, path, buf) stat (path, buf)
-#endif
-
-/* Pathname support.
-   ISSLASH(C)           tests whether C is a directory separator character.
- */
-#if defined _WIN32 || defined __WIN32__ || defined __CYGWIN__ || defined __EMX__ || defined __DJGPP__
-  /* Native Windows, Cygwin, OS/2, DOS */
-# define ISSLASH(C) ((C) == '/' || (C) == '\\')
-#else
-  /* Unix */
-# define ISSLASH(C) ((C) == '/')
-#endif
-
-
-/* Return nonzero if DIR is an existent directory.  */
-static bool
-direxists (const char *dir)
-{
-  struct_stat64 buf;
-  return __xstat64 (_STAT_VER, dir, &buf) == 0 && S_ISDIR (buf.st_mode);
-}
-
-/* Path search algorithm, for tmpnam, tmpfile, etc.  If DIR is
-   non-null and exists, uses it; otherwise uses the first of $TMPDIR,
-   P_tmpdir, /tmp that exists.  Copies into TMPL a template suitable
-   for use with mk[s]temp.  Will fail (-1) if DIR is non-null and
-   doesn't exist, none of the searched dirs exists, or there's not
-   enough space in TMPL. */
-int
-path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx,
-             bool try_tmpdir)
-{
-  const char *d;
-  size_t dlen, plen;
-  bool add_slash;
-
-  if (!pfx || !pfx[0])
-    {
-      pfx = "file";
-      plen = 4;
-    }
-  else
-    {
-      plen = strlen (pfx);
-      if (plen > 5)
-        plen = 5;
-    }
-
-  if (try_tmpdir)
-    {
-      d = __libc_secure_getenv ("TMPDIR");
-      if (d != NULL && direxists (d))
-        dir = d;
-      else if (dir != NULL && direxists (dir))
-        /* nothing */ ;
-      else
-        dir = NULL;
-    }
-  if (dir == NULL)
-    {
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
-      char dirbuf[PATH_MAX];
-      DWORD retval;
-
-      /* Find Windows temporary file directory.
-         We try this before P_tmpdir because Windows defines P_tmpdir to "\\"
-         and will therefore try to put all temporary files in the root
-         directory (unless $TMPDIR is set).  */
-      retval = GetTempPath (PATH_MAX, dirbuf);
-      if (retval > 0 && retval < PATH_MAX && direxists (dirbuf))
-        dir = dirbuf;
-      else
-#endif
-      if (direxists (P_tmpdir))
-        dir = P_tmpdir;
-      else if (strcmp (P_tmpdir, "/tmp") != 0 && direxists ("/tmp"))
-        dir = "/tmp";
-      else
-        {
-          __set_errno (ENOENT);
-          return -1;
-        }
-    }
-
-  dlen = strlen (dir);
-#ifdef __VMS
-  add_slash = 0;
-#else
-  add_slash = dlen != 0 && !ISSLASH (dir[dlen - 1]);
-#endif
-
-  /* check we have room for "${dir}/${pfx}XXXXXX\0" */
-  if (tmpl_len < dlen + add_slash + plen + 6 + 1)
-    {
-      __set_errno (EINVAL);
-      return -1;
-    }
-
-  memcpy (tmpl, dir, dlen);
-  sprintf (tmpl + dlen, &"/%.*sXXXXXX"[!add_slash], (int) plen, pfx);
-  return 0;
-}
diff --git a/contrib/tools/bison/lib/tmpdir.h b/contrib/tools/bison/lib/tmpdir.h
deleted file mode 100644
index ff7c70f346..0000000000
--- a/contrib/tools/bison/lib/tmpdir.h
+++ /dev/null
@@ -1,26 +0,0 @@
-/* Determine a temporary directory.
-   Copyright (C) 2001-2002, 2009-2013 Free Software Foundation, Inc.
-
-   This program is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-#include <stdbool.h>
-#include <stddef.h>
-
-/* Path search algorithm, for tmpnam, tmpfile, etc.  If DIR is
-   non-null and exists, uses it; otherwise uses the first of $TMPDIR,
-   P_tmpdir, /tmp that exists.  Copies into TMPL a template suitable
-   for use with mk[s]temp.  Will fail (-1) if DIR is non-null and
-   doesn't exist, none of the searched dirs exists, or there's not
-   enough space in TMPL. */
-extern int path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx, bool try_tmpdir);
diff --git a/contrib/tools/bison/lib/verror.c b/contrib/tools/bison/lib/verror.c
deleted file mode 100644
index 5f899c1b7a..0000000000
--- a/contrib/tools/bison/lib/verror.c
+++ /dev/null
@@ -1,77 +0,0 @@
-/* va_list error handler for noninteractive utilities
-   Copyright (C) 2006-2007, 2009-2013 Free Software Foundation, Inc.
-
-   This program is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-/* Written by Eric Blake.  */
-
-#include <config.h>
-
-#include "verror.h"
-#include "xvasprintf.h"
-
-#include <errno.h>
-#include <stdarg.h>
-#include <stdlib.h>
-
-#if ENABLE_NLS
-# include "gettext.h"
-# define _(msgid) gettext (msgid)
-#endif
-
-#ifndef _
-# define _(String) String
-#endif
-
-/* Print a message with 'vfprintf (stderr, FORMAT, ARGS)';
-   if ERRNUM is nonzero, follow it with ": " and strerror (ERRNUM).
-   If STATUS is nonzero, terminate the program with 'exit (STATUS)'.
-   Use the globals error_print_progname and error_message_count similarly
-   to error().  */
-void
-verror (int status, int errnum, const char *format, va_list args)
-{
-  verror_at_line (status, errnum, NULL, 0, format, args);
-}
-
-/* Print a message with 'vfprintf (stderr, FORMAT, ARGS)';
-   if ERRNUM is nonzero, follow it with ": " and strerror (ERRNUM).
-   If STATUS is nonzero, terminate the program with 'exit (STATUS)'.
-   If FNAME is not NULL, prepend the message with "FNAME:LINENO:".
-   Use the globals error_print_progname, error_message_count, and
-   error_one_per_line similarly to error_at_line().  */
-void
-verror_at_line (int status, int errnum, const char *file,
-                unsigned int line_number, const char *format, va_list args)
-{
-  char *message = xvasprintf (format, args);
-  if (message)
-    {
-      /* Until http://sourceware.org/bugzilla/show_bug.cgi?id=2997 is fixed,
-         glibc violates GNU Coding Standards when the file argument to
-         error_at_line is NULL.  */
-      if (file)
-        error_at_line (status, errnum, file, line_number, "%s", message);
-      else
-        error (status, errnum, "%s", message);
-    }
-  else
-    {
-      /* EOVERFLOW, EINVAL, and EILSEQ from xvasprintf are signs of
-         serious programmer errors.  */
-      error (0, errno, _("unable to display error message"));
-      abort ();
-    }
-  free (message);
-}
diff --git a/contrib/tools/bison/lib/verror.h b/contrib/tools/bison/lib/verror.h
deleted file mode 100644
index 7e7284ad82..0000000000
--- a/contrib/tools/bison/lib/verror.h
+++ /dev/null
@@ -1,54 +0,0 @@
-/* Declaration for va_list error-reporting function
-   Copyright (C) 2006-2007, 2009-2013 Free Software Foundation, Inc.
-
-   This program is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
-
-#ifndef _VERROR_H
-#define _VERROR_H 1
-
-#include <stdarg.h>
-
-#include "error.h" /* for _GL_ATTRIBUTE_FORMAT */
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* Print a message with 'vfprintf (stderr, FORMAT, ARGS)';
-   if ERRNUM is nonzero, follow it with ": " and strerror (ERRNUM).
-   If STATUS is nonzero, terminate the program with 'exit (STATUS)'.
-   Use the globals error_print_progname and error_message_count similarly
-   to error().  */
-
-extern void verror (int __status, int __errnum, const char *__format,
-                    va_list __args)
-     _GL_ATTRIBUTE_FORMAT ((__printf__, 3, 0));
-
-/* Print a message with 'vfprintf (stderr, FORMAT, ARGS)';
-   if ERRNUM is nonzero, follow it with ": " and strerror (ERRNUM).
-   If STATUS is nonzero, terminate the program with 'exit (STATUS)'.
-   If FNAME is not NULL, prepend the message with "FNAME:LINENO:".
-   Use the globals error_print_progname, error_message_count, and
-   error_one_per_line similarly to error_at_line().  */
-
-extern void verror_at_line (int __status, int __errnum, const char *__fname,
-                            unsigned int __lineno, const char *__format,
-                            va_list __args)
-     _GL_ATTRIBUTE_FORMAT ((__printf__, 5, 0));
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* verror.h */
diff --git a/contrib/tools/bison/lib/ya.make b/contrib/tools/bison/lib/ya.make
index 74520fe268..23f9804554 100644
--- a/contrib/tools/bison/lib/ya.make
+++ b/contrib/tools/bison/lib/ya.make
@@ -93,7 +93,6 @@ SRCS(
     malloca.c
     mbswidth.c
     mbrtowc.c
-    memchr2.c
     mkstemp-safer.c
     nl_langinfo.c
     pipe-safer.c
@@ -107,8 +106,6 @@ SRCS(
     raise.c
     rawmemchr.c
     readlink.c
-    realloc.c
-    regex.c
     rename.c
     rmdir.c
     secure_getenv.c
@@ -121,11 +118,9 @@ SRCS(
     stripslash.c
     tempname.c
     timevar.c
-    tmpdir.c
     unistd.c
     vasnprintf.c
     vbitset.c
-    verror.c
     wait-process.c
     wctype-h.c
     xalloc-die.c
@@ -169,7 +164,6 @@ IF (OS_WINDOWS)
         fseeko.c
         fopen.c
         ftello.c
-        gettimeofday.c
         localeconv.c
         msvc-inval.c
         msvc-nothrow.c
@@ -177,8 +171,6 @@ IF (OS_WINDOWS)
         sigaction.c
         sigprocmask.c
         snprintf.c
-        spawni.c
-        spawnp.c
         strndup.c
         waitpid.c
         wcwidth.c