#!/bin/sh
#
# Libav configure script
#
# Copyright (c) 2000-2002 Fabrice Bellard
# Copyright (c) 2005-2008 Diego Biurrun
# Copyright (c) 2005-2008 Mans Rullgard
#

# Prevent locale nonsense from breaking basic text processing.
LC_ALL=C
export LC_ALL

# make sure we are running under a compatible shell
# try to make this part work with most shells

try_exec(){
    echo "Trying shell $1"
    type "$1" > /dev/null 2>&1 && exec "$@"
}

unset foo
(: ${foo%%bar}) 2> /dev/null
E1="$?"

(: ${foo?}) 2> /dev/null
E2="$?"

if test "$E1" != 0 || test "$E2" = 0; then
    echo "Broken shell detected.  Trying alternatives."
    export FF_CONF_EXEC
    if test "0$FF_CONF_EXEC" -lt 1; then
        FF_CONF_EXEC=1
        try_exec bash "$0" "$@"
    fi
    if test "0$FF_CONF_EXEC" -lt 2; then
        FF_CONF_EXEC=2
        try_exec ksh "$0" "$@"
    fi
    if test "0$FF_CONF_EXEC" -lt 3; then
        FF_CONF_EXEC=3
        try_exec /usr/xpg4/bin/sh "$0" "$@"
    fi
    echo "No compatible shell script interpreter found."
    echo "This configure script requires a POSIX-compatible shell"
    echo "such as bash or ksh."
    echo "THIS IS NOT A BUG IN LIBAV, DO NOT REPORT IT AS SUCH."
    echo "Instead, install a working POSIX-compatible shell."
    echo "Disabling this configure test will create a broken Libav."
    if test "$BASH_VERSION" = '2.04.0(1)-release'; then
        echo "This bash version ($BASH_VERSION) is broken on your platform."
        echo "Upgrade to a later version if available."
    fi
    exit 1
fi

test -d /usr/xpg4/bin && PATH=/usr/xpg4/bin:$PATH

show_help(){
    cat <<EOF
Usage: configure [options]
Options: [defaults in brackets after descriptions]

Help options:
  --help                   print this message
  --list-decoders          show all available decoders
  --list-encoders          show all available encoders
  --list-hwaccels          show all available hardware accelerators
  --list-demuxers          show all available demuxers
  --list-muxers            show all available muxers
  --list-parsers           show all available parsers
  --list-protocols         show all available protocols
  --list-bsfs              show all available bitstream filters
  --list-indevs            show all available input devices
  --list-outdevs           show all available output devices
  --list-filters           show all available filters

Standard options:
  --logfile=FILE           log tests and output to FILE [config.log]
  --disable-logging        do not log configure debug information
  --prefix=PREFIX          install in PREFIX [$prefix]
  --bindir=DIR             install binaries in DIR [PREFIX/bin]
  --datadir=DIR            install data files in DIR [PREFIX/share/avconv]
  --docdir=DIR             install documentation in DIR [PREFIX/share/doc/libav]
  --libdir=DIR             install libs in DIR [PREFIX/lib]
  --shlibdir=DIR           install shared libs in DIR [PREFIX/lib]
  --incdir=DIR             install includes in DIR [PREFIX/include]
  --mandir=DIR             install man page in DIR [PREFIX/share/man]
  --enable-rpath           use rpath when linking programs [USE WITH CARE]

Licensing options:
  --enable-gpl             allow use of GPL code, the resulting libs
                           and binaries will be under GPL [no]
  --enable-version3        upgrade (L)GPL to version 3 [no]
  --enable-nonfree         allow use of nonfree code, the resulting libs
                           and binaries will be unredistributable [no]

Configuration options:
  --disable-static         do not build static libraries [no]
  --enable-shared          build shared libraries [no]
  --enable-small           optimize for size instead of speed
  --enable-runtime-cpudetect detect cpu capabilities at runtime (bigger binary)
  --enable-gray            enable full grayscale support (slower color)
  --disable-swscale-alpha  disable alpha channel support in swscale
  --disable-all            disable building components, libraries and programs

Program options:
  --disable-programs       do not build command line programs
  --disable-avconv         disable avconv build
  --disable-avplay         disable avplay build
  --disable-avprobe        disable avprobe build
  --disable-avserver       deprecated, does nothing

Component options:
  --disable-doc            do not build documentation
  --disable-avdevice       disable libavdevice build
  --disable-avcodec        disable libavcodec build
  --disable-avformat       disable libavformat build
  --disable-avutil         disable libavutil build
  --disable-swscale        disable libswscale build
  --disable-avfilter       disable video filter support [no]
  --disable-avresample     disable libavresample build [no]
  --disable-pthreads       disable pthreads [auto]
  --disable-w32threads     disable Win32 threads [auto]
  --disable-network        disable network support [no]
  --disable-dct            disable DCT code
  --disable-error-resilience disable error resilience code
  --disable-lsp            disable LSP code
  --disable-lzo            disable LZO decoder code
  --disable-mdct           disable MDCT code
  --disable-rdft           disable RDFT code
  --disable-fft            disable FFT code
  --disable-faan           disable floating point AAN (I)DCT code

Hardware accelerators:
  --enable-d3d11va         enable D3D11VA code
  --enable-dxva2           enable DXVA2 code
  --enable-vaapi           enable VAAPI code
  --enable-vda             enable VDA code
  --enable-vdpau           enable VDPAU code

Individual component options:
  --disable-everything     disable all components listed below
  --disable-encoder=NAME   disable encoder NAME
  --enable-encoder=NAME    enable encoder NAME
  --disable-encoders       disable all encoders
  --disable-decoder=NAME   disable decoder NAME
  --enable-decoder=NAME    enable decoder NAME
  --disable-decoders       disable all decoders
  --disable-hwaccel=NAME   disable hwaccel NAME
  --enable-hwaccel=NAME    enable hwaccel NAME
  --disable-hwaccels       disable all hwaccels
  --disable-muxer=NAME     disable muxer NAME
  --enable-muxer=NAME      enable muxer NAME
  --disable-muxers         disable all muxers
  --disable-demuxer=NAME   disable demuxer NAME
  --enable-demuxer=NAME    enable demuxer NAME
  --disable-demuxers       disable all demuxers
  --enable-parser=NAME     enable parser NAME
  --disable-parser=NAME    disable parser NAME
  --disable-parsers        disable all parsers
  --enable-bsf=NAME        enable bitstream filter NAME
  --disable-bsf=NAME       disable bitstream filter NAME
  --disable-bsfs           disable all bitstream filters
  --enable-protocol=NAME   enable protocol NAME
  --disable-protocol=NAME  disable protocol NAME
  --disable-protocols      disable all protocols
  --enable-indev=NAME      enable input device NAME
  --disable-indev=NAME     disable input device NAME
  --disable-indevs         disable input devices
  --enable-outdev=NAME     enable output device NAME
  --disable-outdev=NAME    disable output device NAME
  --disable-outdevs        disable output devices
  --disable-devices        disable all devices
  --enable-filter=NAME     enable filter NAME
  --disable-filter=NAME    disable filter NAME
  --disable-filters        disable all filters

External library support:
  --enable-avisynth        enable reading of AviSynth script files [no]
  --enable-bzlib           enable bzlib [autodetect]
  --enable-frei0r          enable frei0r video filtering
  --enable-gnutls          enable gnutls [no]
  --enable-libbs2b         enable bs2b DSP library [no]
  --enable-libcdio         enable audio CD grabbing with libcdio
  --enable-libdc1394       enable IIDC-1394 grabbing using libdc1394
                           and libraw1394 [no]
  --enable-libdcadec       enable DCA decoding via libdcadec [no]
  --enable-libfaac         enable AAC encoding via libfaac [no]
  --enable-libfdk-aac      enable AAC de/encoding via libfdk-aac [no]
  --enable-libfreetype     enable libfreetype [no]
  --enable-libgsm          enable GSM de/encoding via libgsm [no]
  --enable-libilbc         enable iLBC de/encoding via libilbc [no]
  --enable-libkvazaar      enable HEVC encoding via libkvazaar [no]
  --enable-libmfx          enable HW acceleration through libmfx
  --enable-libmp3lame      enable MP3 encoding via libmp3lame [no]
  --enable-libopencore-amrnb enable AMR-NB de/encoding via libopencore-amrnb [no]
  --enable-libopencore-amrwb enable AMR-WB decoding via libopencore-amrwb [no]
  --enable-libopencv       enable video filtering via libopencv [no]
  --enable-libopenh264     enable H.264 encoding via OpenH264 [no]
  --enable-libopenjpeg     enable JPEG 2000 de/encoding via OpenJPEG [no]
  --enable-libopus         enable Opus de/encoding via libopus [no]
  --enable-libpulse        enable Pulseaudio input via libpulse [no]
  --enable-librtmp         enable RTMP[E] support via librtmp [no]
  --enable-libschroedinger enable Dirac de/encoding via libschroedinger [no]
  --enable-libsnappy       enable Snappy compression [no]
  --enable-libspeex        enable Speex de/encoding via libspeex [no]
  --enable-libtheora       enable Theora encoding via libtheora [no]
  --enable-libtwolame      enable MP2 encoding via libtwolame [no]
  --enable-libvo-aacenc    enable AAC encoding via libvo-aacenc [no]
  --enable-libvo-amrwbenc  enable AMR-WB encoding via libvo-amrwbenc [no]
  --enable-libvorbis       enable Vorbis encoding via libvorbis [no]
  --enable-libvpx          enable VP8 and VP9 de/encoding via libvpx [no]
  --enable-libwavpack      enable wavpack encoding via libwavpack [no]
  --enable-libwebp         enable WebP encoding via libwebp [no]
  --enable-libx264         enable H.264 encoding via x264 [no]
  --enable-libx265         enable HEVC encoding via x265 [no]
  --enable-libxavs         enable AVS encoding via xavs [no]
  --enable-libxcb          enable X11 grabbing using XCB [no]
  --enable-libxcb-shm      enable X11 grabbing shm communication [auto]
  --enable-libxcb-xfixes   enable X11 grabbing mouse rendering [auto]
  --enable-libxvid         enable Xvid encoding via xvidcore,
                           native MPEG-4/Xvid encoder exists [no]
  --enable-mmal            enable decoding via MMAL [no]
  --enable-nvenc           enable encoding via NVENC [no]
  --enable-openssl         enable openssl [no]
  --enable-x11grab         enable X11 grabbing (legacy) [no]
  --enable-zlib            enable zlib [autodetect]

Toolchain options:
  --arch=ARCH              select architecture [$arch]
  --cpu=CPU                select the minimum required CPU (affects
                           instruction selection, may crash on older CPUs)
  --cross-prefix=PREFIX    use PREFIX for compilation tools [$cross_prefix]
  --enable-cross-compile   assume a cross-compiler is used
  --sysroot=PATH           root of cross-build tree
  --sysinclude=PATH        location of cross-build system headers
  --target-os=OS           compiler targets OS [$target_os]
  --target-exec=CMD        command to run executables on target
  --target-path=DIR        path to view of build directory on target
  --target-samples=DIR     path to samples directory on target
  --toolchain=NAME         set tool defaults according to NAME
  --nm=NM                  use nm tool
  --ar=AR                  use archive tool AR [$ar_default]
  --as=AS                  use assembler AS [$as_default]
  --cc=CC                  use C compiler CC [$cc_default]
  --objcc=OCC              use ObjC compiler OCC [$cc_default]
  --dep-cc=DEPCC           use dependency generator DEPCC [$cc_default]
  --ld=LD                  use linker LD
  --pkg-config=PKGCONFIG   use pkg-config tool PKGCONFIG [$pkg_config_default]
  --pkg-config-flags=FLAGS pass additional flags to pkgconf []
  --host-cc=HOSTCC         use host C compiler HOSTCC
  --host-cflags=HCFLAGS    use HCFLAGS when compiling for host
  --host-cppflags=HCPPFLAGS use HCPPFLAGS when compiling for host
  --host-ld=HOSTLD         use host linker HOSTLD
  --host-ldflags=HLDFLAGS  use HLDFLAGS when linking for host
  --host-libs=HLIBS        use libs HLIBS when linking for host
  --host-os=OS             compiler host OS [$target_os]
  --extra-cflags=ECFLAGS   add ECFLAGS to CFLAGS [$CFLAGS]
  --extra-objcflags=FLAGS  add FLAGS to OBJCFLAGS [$CFLAGS]
  --extra-ldflags=ELDFLAGS add ELDFLAGS to LDFLAGS [$LDFLAGS]
  --extra-ldexeflags=ELDFLAGS add ELDFLAGS to LDEXEFLAGS [$LDEXEFLAGS]
  --extra-libs=ELIBS       add ELIBS [$ELIBS]
  --extra-version=STRING   version string suffix []
  --optflags=OPTFLAGS      override optimization-related compiler flags
  --build-suffix=SUFFIX    library name suffix []
  --enable-pic             build position-independent code
  --enable-thumb           compile for Thumb instruction set
  --enable-lto             use link-time optimization
  --env="ENV=override"     override the environment variables

Advanced options (experts only):
  --malloc-prefix=PREFIX   prefix malloc and related names with PREFIX
  --custom-allocator=NAME  use a supported custom allocator
  --disable-symver         disable symbol versioning
  --enable-hardcoded-tables use hardcoded tables instead of runtime generation
  --disable-safe-bitstream-reader
                           disable buffer boundary checking in bitreaders
                           (faster, but may crash)
  --enable-memalign-hack   emulate memalign, interferes with memory debuggers
  --enable-sram            allow use of on-chip SRAM

Optimization options (experts only):
  --disable-asm            disable all assembly optimizations
  --disable-altivec        disable AltiVec optimizations
  --disable-vsx            disable VSX optimizations
  --disable-power8         disable POWER8 optimizations
  --disable-amd3dnow       disable 3DNow! optimizations
  --disable-amd3dnowext    disable 3DNow! extended optimizations
  --disable-mmx            disable MMX optimizations
  --disable-mmxext         disable MMXEXT optimizations
  --disable-sse            disable SSE optimizations
  --disable-sse2           disable SSE2 optimizations
  --disable-sse3           disable SSE3 optimizations
  --disable-ssse3          disable SSSE3 optimizations
  --disable-sse4           disable SSE4 optimizations
  --disable-sse42          disable SSE4.2 optimizations
  --disable-avx            disable AVX optimizations
  --disable-xop            disable XOP optimizations
  --disable-fma3           disable FMA3 optimizations
  --disable-fma4           disable FMA4 optimizations
  --disable-avx2           disable AVX2 optimizations
  --disable-armv5te        disable armv5te optimizations
  --disable-armv6          disable armv6 optimizations
  --disable-armv6t2        disable armv6t2 optimizations
  --disable-vfp            disable VFP optimizations
  --disable-neon           disable NEON optimizations
  --disable-inline-asm     disable use of inline assembly
  --disable-yasm           disable use of nasm/yasm assembly

Developer options (useful when working on Libav itself):
  --disable-debug          disable debugging symbols
  --enable-debug=LEVEL     set the debug level [$debuglevel]
  --disable-optimizations  disable compiler optimizations
  --enable-extra-warnings  enable more compiler warnings
  --samples=PATH           location of test samples for FATE, if not set use
                           \$LIBAV_SAMPLES at make invocation time.
  --enable-neon-clobber-test check NEON registers for clobbering (should be
                           used only for debugging purposes)
  --enable-xmm-clobber-test check XMM registers for clobbering (Win64-only;
                           should be used only for debugging purposes)
  --enable-random          randomly enable/disable components
  --disable-random
  --enable-random=LIST     randomly enable/disable specific components or
  --disable-random=LIST    component groups. LIST is a comma-separated list
                           of NAME[:PROB] entries where NAME is a component
                           (group) and PROB the probability associated with
                           NAME (default 0.5).
  --random-seed=VALUE      seed value for --enable/disable-random
  --disable-valgrind-backtrace do not print a backtrace under Valgrind
                           (only applies to --disable-optimizations builds)

NOTE: Object files are built at the place where configure is launched.
EOF
  exit 0
}

quotes='""'

log(){
    echo "$@" >> $logfile
}

log_file(){
    log BEGIN $1
    i=1
    while read line; do
        printf '%5s   %s\n' "${i}" "${line}"
        i=$(($i+1))
    done < $1 >> $logfile
    log END $1
}

echolog(){
    log "$@"
    echo "$@"
}

warn(){
    log "WARNING: $*"
    WARNINGS="${WARNINGS}WARNING: $*\n"
}

die(){
    echolog "$@"
    cat <<EOF

If you think configure made a mistake, make sure you are using the latest
version from Git.  If the latest version fails, report the problem to the
libav-tools@libav.org mailing list or IRC #libav on irc.freenode.net.
EOF
    if disabled logging; then
        cat <<EOF
Rerun configure with logging enabled (do not use --disable-logging), and
include the log this produces with your report.
EOF
    else
        cat <<EOF
Include the log file "$logfile" produced by configure as this will help
solving the problem.
EOF
    fi
    exit 1
}

# Avoid locale weirdness, besides we really just want to translate ASCII.
toupper(){
    echo "$@" | tr abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ
}

tolower(){
    echo "$@" | tr ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz
}

c_escape(){
    echo "$*" | sed 's/["\\]/\\\0/g'
}

sh_quote(){
    v=$(echo "$1" | sed "s/'/'\\\\''/g")
    test "x$v" = "x${v#*[!A-Za-z0-9_/.+-]}" || v="'$v'"
    echo "$v"
}

cleanws(){
    echo "$@" | sed 's/^ *//;s/  */ /g;s/ *$//'
}

filter(){
    pat=$1
    shift
    for v; do
        eval "case $v in $pat) echo $v ;; esac"
    done
}

filter_out(){
    pat=$1
    shift
    for v; do
        eval "case $v in $pat) ;; *) echo $v ;; esac"
    done
}

map(){
    m=$1
    shift
    for v; do eval $m; done
}

add_suffix(){
    suffix=$1
    shift
    for v; do echo ${v}${suffix}; done
}

set_all(){
    value=$1
    shift
    for var in $*; do
        eval $var=$value
    done
}

set_weak(){
    value=$1
    shift
    for var; do
        eval : \${$var:=$value}
    done
}

sanitize_var_name(){
    echo $@ | sed 's/[^A-Za-z0-9_]/_/g'
}

set_safe(){
    var=$1
    shift
    eval $(sanitize_var_name "$var")='$*'
}

get_safe(){
    eval echo \$$(sanitize_var_name "$1")
}

pushvar(){
    for pvar in $*; do
        eval level=\${${pvar}_level:=0}
        eval ${pvar}_${level}="\$$pvar"
        eval ${pvar}_level=$(($level+1))
    done
}

popvar(){
    for pvar in $*; do
        eval level=\${${pvar}_level:-0}
        test $level = 0 && continue
        eval level=$(($level-1))
        eval $pvar="\${${pvar}_${level}}"
        eval ${pvar}_level=$level
        eval unset ${pvar}_${level}
    done
}

enable(){
    set_all yes $*
}

check_requested() {
    for var; do
        eval test "x\$${var#!}_requested" = "xyes" &&  die "${var#*_} ${var/_*} cannot be enabled"
    done
}

disable(){
    set_all no $*
    check_requested $*
}

enable_weak(){
    set_weak yes $*
}

disable_weak(){
    set_weak no $*
}

enable_safe(){
    for var; do
        enable $(echo "$var" | sed 's/[^A-Za-z0-9_]/_/g')
    done
}

disable_safe(){
    for var; do
        disable $(echo "$var" | sed 's/[^A-Za-z0-9_]/_/g')
    done
}

do_enable_deep(){
    for var; do
        enabled $var && continue
        eval sel="\$${var}_select"
        eval sgs="\$${var}_suggest"
        pushvar var sgs
        enable_deep $sel
        popvar sgs
        enable_deep_weak $sgs
        popvar var
    done
}

enable_deep(){
    do_enable_deep $*
    enable $*
}

enable_deep_weak(){
    for var; do
        disabled $var && continue
        pushvar var
        do_enable_deep $var
        popvar var
        enable_weak $var
    done
}

do_enable_deep_force(){
    for var; do
        enabled $var && continue
        eval sel="\$${var}_select\ \$${var}_suggest\ \$${var}_select_any"
        pushvar var
        enable_deep_force $sel
        popvar var
    done
}

enable_deep_force(){
    do_enable_deep_force $*
    enable $*
}

request(){
    for var; do
        enable ${var}_requested
    done
    enable_deep_force $*
}

enabled(){
    test "${1#!}" = "$1" && op== || op=!=
    eval test "x\$${1#!}" $op "xyes"
}

disabled(){
    test "${1#!}" = "$1" && op== || op=!=
    eval test "x\$${1#!}" $op "xno"
}

enabled_all(){
    for opt; do
        enabled $opt || return 1
    done
}

disabled_all(){
    for opt; do
        disabled $opt || return 1
    done
}

enabled_any(){
    for opt; do
        enabled $opt && return 0
    done
}

disabled_any(){
    for opt; do
        disabled $opt && return 0
    done
    return 1
}

set_default(){
    for opt; do
        eval : \${$opt:=\$${opt}_default}
    done
}

is_in(){
    value=$1
    shift
    for var in $*; do
        [ $var = $value ] && return 0
    done
    return 1
}

do_check_deps(){
    for cfg; do
        cfg="${cfg#!}"
        enabled ${cfg}_checking && die "Circular dependency for $cfg."
        disabled ${cfg}_checking && continue
        enable ${cfg}_checking
        append allopts $cfg

        eval dep_all="\$${cfg}_deps"
        eval dep_any="\$${cfg}_deps_any\ \$${cfg}_select_any"
        eval dep_sel="\$${cfg}_select"
        eval dep_sgs="\$${cfg}_suggest"
        eval dep_ifa="\$${cfg}_if"
        eval dep_ifn="\$${cfg}_if_any"

        pushvar cfg dep_all dep_any dep_sel dep_sgs dep_ifa dep_ifn
        do_check_deps $dep_all $dep_any $dep_sel $dep_sgs $dep_ifa $dep_ifn
        popvar cfg dep_all dep_any dep_sel dep_sgs dep_ifa dep_ifn

        [ -n "$dep_ifa" ] && { enabled_all $dep_ifa && enable_weak $cfg; }
        [ -n "$dep_ifn" ] && { enabled_any $dep_ifn && enable_weak $cfg; }
        enabled_all  $dep_all || disable $cfg
        enabled_any  $dep_any || disable $cfg
        disabled_any $dep_sel && disable $cfg

        if enabled $cfg; then
            enable_deep $dep_sel
            enable_deep_weak $dep_sgs
        fi

        disable ${cfg}_checking
    done
}

check_deps(){
    unset allopts

    do_check_deps "$@"

    for cfg in $allopts; do
        enabled $cfg || continue
        eval dep_extralibs="\$${cfg}_extralibs"
        test -n "$dep_extralibs" && add_extralibs $dep_extralibs
    done
}

print_config(){
    pfx=$1
    files=$2
    shift 2
    map 'eval echo "$v \${$v:-no}"' "$@" |
    awk "BEGIN { split(\"$files\", files) }
        {
            c = \"$pfx\" toupper(\$1);
            v = \$2;
            sub(/yes/, 1, v);
            sub(/no/,  0, v);
            for (f in files) {
                file = files[f];
                if (file ~ /\\.h\$/) {
                    printf(\"#define %s %d\\n\", c, v) >>file;
                } else if (file ~ /\\.asm\$/) {
                    printf(\"%%define %s %d\\n\", c, v) >>file;
                } else if (file ~ /\\.mak\$/) {
                    n = -v ? \"\" : \"!\";
                    printf(\"%s%s=yes\\n\", n, c) >>file;
                }
            }
        }"
}

print_enabled(){
    suf=$1
    shift
    for v; do
        enabled $v && printf "%s\n" ${v%$suf};
    done
}

append(){
    var=$1
    shift
    eval "$var=\"\$$var $*\""
}

prepend(){
    var=$1
    shift
    eval "$var=\"$* \$$var\""
}

unique(){
    var=$1
    uniq_list=""
    for tok in $(eval echo \$$var); do
        uniq_list="$(filter_out $tok $uniq_list) $tok"
    done
    eval "$var=\"${uniq_list}\""
}

add_cppflags(){
    append CPPFLAGS "$@"
}

add_cflags(){
    append CFLAGS $($cflags_filter "$@")
}

add_asflags(){
    append ASFLAGS $($asflags_filter "$@")
}

add_objcflags(){
    append OBJCFLAGS $($objcflags_filter "$@")
}

add_ldflags(){
    append LDFLAGS $($ldflags_filter "$@")
}

add_ldexeflags(){
    append LDEXEFLAGS $($ldflags_filter "$@")
}

add_stripflags(){
    append STRIPFLAGS "$@"
}

add_extralibs(){
    prepend extralibs $($ldflags_filter "$@")
}

add_host_cppflags(){
    append host_cppflags "$@"
}

add_host_cflags(){
    append host_cflags $($host_cflags_filter "$@")
}

add_host_ldflags(){
    append host_ldflags $($host_ldflags_filter "$@")
}

add_compat(){
    append compat_objs $1
    shift
    map 'add_cppflags -D$v' "$@"
}

check_cmd(){
    log "$@"
    "$@" >> $logfile 2>&1
}

cc_o(){
    eval printf '%s\\n' $CC_O
}

cc_e(){
    eval printf '%s\\n' $CC_E
}

check_cc(){
    log check_cc "$@"
    cat > $TMPC
    log_file $TMPC
    check_cmd $cc $CPPFLAGS $CFLAGS "$@" $CC_C $(cc_o $TMPO) $TMPC
}

check_objcc(){
    log check_objcc "$@"
    cat > $TMPC
    log_file $TMPC
    check_cmd $objcc $CPPFLAGS $CFLAGS $OBJCFLAGS "$@" $OBJCC_C $(cc_o $TMPO) $TMPC
}

check_cpp(){
    log check_cpp "$@"
    cat > $TMPC
    log_file $TMPC
    check_cmd $cc $CPPFLAGS $CFLAGS "$@" $(cc_e $TMPO) $TMPC
}

as_o(){
    eval printf '%s\\n' $AS_O
}

check_as(){
    log check_as "$@"
    cat > $TMPS
    log_file $TMPS
    check_cmd $as $CPPFLAGS $ASFLAGS "$@" $AS_C $(as_o $TMPO) $TMPS
}

check_inline_asm(){
    log check_inline_asm "$@"
    name="$1"
    code="$2"
    shift 2
    disable $name
    check_cc "$@" <<EOF && enable $name
void foo(void){ __asm__ volatile($code); }
EOF
}

check_insn(){
    log check_insn "$@"
    check_inline_asm ${1}_inline "\"$2\""
    echo "$2" | check_as && enable ${1}_external || disable ${1}_external
}

check_yasm(){
    log check_yasm "$@"
    echo "$1" > $TMPS
    log_file $TMPS
    shift 1
    check_cmd $yasmexe $YASMFLAGS "$@" -o $TMPO $TMPS
}

ld_o(){
    eval printf '%s\\n' $LD_O
}

check_ld(){
    log check_ld "$@"
    flags=$(filter_out '-l*' "$@")
    libs=$(filter '-l*' "$@")
    check_cc $($cflags_filter $flags) || return
    flags=$($ldflags_filter $flags)
    libs=$($ldflags_filter $libs)
    check_cmd $ld $LDFLAGS $flags $(ld_o $TMPE) $TMPO $libs $extralibs
}

print_include(){
    hdr=$1
    test "${hdr%.h}" = "${hdr}" &&
        echo "#include $hdr"    ||
        echo "#include <$hdr>"
}

check_code(){
    log check_code "$@"
    check=$1
    headers=$2
    code=$3
    shift 3
    {
        for hdr in $headers; do
            print_include $hdr
        done
        echo "int main(void) { $code; return 0; }"
    } | check_$check "$@"
}

check_cppflags(){
    log check_cppflags "$@"
    check_cc "$@" <<EOF && append CPPFLAGS "$@"
int x;
EOF
}

test_cflags(){
    log test_cflags "$@"
    set -- $($cflags_filter "$@")
    check_cc "$@" <<EOF
int x;
EOF
}

check_cflags(){
    log check_cflags "$@"
    test_cflags "$@" && add_cflags "$@"
}

test_objcflags(){
    log test_cflags "$@"
    set -- $($cflags_filter "$@")
    check_objcc "$@" <<EOF
int x;
EOF
}

check_objcflags(){
    log check_cflags "$@"
    test_objcflags "$@" && add_objcflags "$@"
}

test_ldflags(){
    log test_ldflags "$@"
    check_ld "$@" <<EOF
int main(void){ return 0; }
EOF
}

check_ldflags(){
    log check_ldflags "$@"
    test_ldflags "$@" && add_ldflags "$@"
}

test_stripflags(){
    log test_stripflags "$@"
    # call check_cc to get a fresh TMPO
    check_cc <<EOF
int main(void) { return 0; }
EOF
    check_cmd $strip $STRIPFLAGS "$@" $TMPO
}

check_stripflags(){
    log check_stripflags "$@"
    test_stripflags "$@" && add_stripflags "$@"
}

check_header(){
    log check_header "$@"
    header=$1
    shift
    disable_safe $header
    check_cpp "$@" <<EOF && enable_safe $header
#include <$header>
int x;
EOF
}

check_func(){
    log check_func "$@"
    func=$1
    shift
    disable $func
    check_ld "$@" <<EOF && enable $func
extern int $func();
int main(void){ $func(); }
EOF
}

check_mathfunc(){
    log check_mathfunc "$@"
    func=$1
    narg=$2
    shift 2
    test $narg = 2 && args="f, g" || args="f"
    disable $func
    check_ld "$@" <<EOF && enable $func
#include <math.h>
float foo(float f, float g) { return $func($args); }
int main(void){ return 0; }
EOF
}

check_func_headers(){
    log check_func_headers "$@"
    headers=$1
    funcs=$2
    shift 2
    {
        for hdr in $headers; do
            print_include $hdr
        done
        for func in $funcs; do
            echo "long check_$func(void) { return (long) $func; }"
        done
        echo "int main(void) { return 0; }"
    } | check_ld "$@" && enable $funcs && enable_safe $headers
}

check_cpp_condition(){
    log check_cpp_condition "$@"
    header=$1
    condition=$2
    shift 2
    check_cpp "$@" <<EOF
#include <$header>
#if !($condition)
#error "unsatisfied condition: $condition"
#endif
EOF
}

check_lib(){
    log check_lib "$@"
    header="$1"
    func="$2"
    shift 2
    check_header $header && check_func $func "$@" && add_extralibs "$@"
}

check_lib2(){
    log check_lib2 "$@"
    headers="$1"
    funcs="$2"
    shift 2
    check_func_headers "$headers" "$funcs" "$@" && add_extralibs "$@"
}

check_pkg_config(){
    log check_pkg_config "$@"
    pkg="$1"
    headers="$2"
    funcs="$3"
    shift 3
    check_cmd $pkg_config --exists --print-errors $pkg || return
    pkg_cflags=$($pkg_config --cflags $pkg_config_flags $pkg)
    pkg_libs=$($pkg_config --libs $pkg_config_flags $pkg)
    check_func_headers "$headers" "$funcs" $pkg_cflags $pkg_libs "$@" &&
        set_safe "${pkg}_cflags" $pkg_cflags   &&
        set_safe "${pkg}_libs"   $pkg_libs
}

check_exec(){
    check_ld "$@" && { enabled cross_compile || $TMPE >> $logfile 2>&1; }
}

check_exec_crash(){
    code=$(cat)

    # exit() is not async signal safe.  _Exit (C99) and _exit (POSIX)
    # are safe but may not be available everywhere.  Thus we use
    # raise(SIGTERM) instead.  The check is run in a subshell so we
    # can redirect the "Terminated" message from the shell.  SIGBUS
    # is not defined by standard C so it is used conditionally.

    (check_exec "$@") >> $logfile 2>&1 <<EOF
#include <signal.h>
static void sighandler(int sig){
    raise(SIGTERM);
}
int foo(void){
    $code
}
int (*func_ptr)(void) = foo;
int main(void){
    signal(SIGILL, sighandler);
    signal(SIGFPE, sighandler);
    signal(SIGSEGV, sighandler);
#ifdef SIGBUS
    signal(SIGBUS, sighandler);
#endif
    return func_ptr();
}
EOF
}

check_type(){
    log check_type "$@"
    headers=$1
    type=$2
    shift 2
    disable_safe "$type"
    check_code cc "$headers" "$type v" "$@" && enable_safe "$type"
}

check_struct(){
    log check_struct "$@"
    headers=$1
    struct=$2
    member=$3
    shift 3
    disable_safe "${struct}_${member}"
    check_code cc "$headers" "const void *p = &(($struct *)0)->$member" "$@" &&
        enable_safe "${struct}_${member}"
}

check_builtin(){
    log check_builtin "$@"
    name=$1
    headers=$2
    builtin=$3
    shift 3
    disable "$name"
    check_code ld "$headers" "$builtin" "$@" && enable "$name"
}

check_compile_assert(){
    log check_compile_assert "$@"
    name=$1
    headers=$2
    condition=$3
    shift 3
    disable "$name"
    check_code cc "$headers" "char c[2 * !!($condition) - 1]" "$@" && enable "$name"
}

require(){
    name="$1"
    header="$2"
    func="$3"
    shift 3
    check_lib $header $func "$@" || die "ERROR: $name not found"
}

require2(){
    name="$1"
    headers="$2"
    func="$3"
    shift 3
    check_lib2 "$headers" $func "$@" || die "ERROR: $name not found"
}

require_pkg_config(){
    pkg="$1"
    check_pkg_config "$@" || die "ERROR: $pkg not found"
    add_cflags    $(get_safe "${pkg}_cflags")
    add_extralibs $(get_safe "${pkg}_libs")
}

hostcc_e(){
    eval printf '%s\\n' $HOSTCC_E
}

hostcc_o(){
    eval printf '%s\\n' $HOSTCC_O
}

check_host_cc(){
    log check_host_cc "$@"
    cat > $TMPC
    log_file $TMPC
    check_cmd $host_cc $host_cflags "$@" $HOSTCC_C $(hostcc_o $TMPO) $TMPC
}

check_host_cpp(){
    log check_host_cpp "$@"
    cat > $TMPC
    log_file $TMPC
    check_cmd $host_cc $host_cppflags $host_cflags "$@" $(hostcc_e $TMPO) $TMPC
}

check_host_cppflags(){
    log check_host_cppflags "$@"
    check_host_cc "$@" <<EOF && append host_cppflags "$@"
int x;
EOF
}

check_host_cflags(){
    log check_host_cflags "$@"
    set -- $($host_cflags_filter "$@")
    check_host_cc "$@" <<EOF && append host_cflags "$@"
int x;
EOF
}

check_host_cpp_condition(){
    log check_host_cpp_condition "$@"
    header=$1
    condition=$2
    shift 2
    check_host_cpp "$@" <<EOF
#include <$header>
#if !($condition)
#error "unsatisfied condition: $condition"
#endif
EOF
}

apply(){
    file=$1
    shift
    "$@" < "$file" > "$file.tmp" && mv "$file.tmp" "$file" || rm "$file.tmp"
}

cp_if_changed(){
    cmp -s "$1" "$2" && echo "$2 is unchanged" && return
    mkdir -p "$(dirname $2)"
    $cp_f "$1" "$2"
}

# CONFIG_LIST contains configurable options, while HAVE_LIST is for
# system-dependent things.

AVCODEC_COMPONENTS="
    bsfs
    decoders
    encoders
    hwaccels
    parsers
"

AVDEVICE_COMPONENTS="
    indevs
    outdevs
"
AVFILTER_COMPONENTS="
    filters
"
AVFORMAT_COMPONENTS="
    demuxers
    muxers
    protocols
"

AVRESAMPLE_COMPONENTS=""
AVUTIL_COMPONENTS=""

COMPONENT_LIST="
    $AVCODEC_COMPONENTS
    $AVDEVICE_COMPONENTS
    $AVFILTER_COMPONENTS
    $AVFORMAT_COMPONENTS
    $AVRESAMPLE_COMPONENTS
    $AVUTIL_COMPONENTS
"

EXAMPLE_LIST="
    avcodec_example
    filter_audio_example
    metadata_example
    output_example
    qsvdec_example
    transcode_aac_example
"

EXTERNAL_LIBRARY_LIST="
    avisynth
    bzlib
    frei0r
    gnutls
    libbs2b
    libcdio
    libdc1394
    libdcadec
    libfaac
    libfdk_aac
    libfontconfig
    libfreetype
    libgsm
    libilbc
    libkvazaar
    libmfx
    libmp3lame
    libopencore_amrnb
    libopencore_amrwb
    libopencv
    libopenh264
    libopenjpeg
    libopus
    libpulse
    librtmp
    libschroedinger
    libsnappy
    libspeex
    libtheora
    libtwolame
    libvo_aacenc
    libvo_amrwbenc
    libvorbis
    libvpx
    libwavpack
    libwebp
    libx264
    libx265
    libxavs
    libxcb
    libxcb_shm
    libxcb_xfixes
    libxvid
    mmal
    nvenc
    openssl
    x11grab
    zlib
"

FEATURE_LIST="
    gray
    hardcoded_tables
    runtime_cpudetect
    safe_bitstream_reader
    shared
    small
    sram
    static
    swscale_alpha
"

HWACCEL_LIST="
    d3d11va
    dxva2
    vaapi
    vda
    vdpau
"

LIBRARY_LIST="
    avcodec
    avdevice
    avfilter
    avformat
    avresample
    avutil
    swscale
"

LICENSE_LIST="
    gpl
    nonfree
    version3
"

PROGRAM_LIST="
    avconv
    avplay
    avprobe
"

SUBSYSTEM_LIST="
    dct
    doc
    error_resilience
    faan
    fft
    lsp
    lzo
    mdct
    network
    rdft
"

CONFIG_LIST="
    $COMPONENT_LIST
    $EXAMPLE_LIST
    $EXTERNAL_LIBRARY_LIST
    $FEATURE_LIST
    $HWACCEL_LIST
    $LICENSE_LIST
    $LIBRARY_LIST
    $PROGRAM_LIST
    $SUBSYSTEM_LIST
    memalign_hack
    neon_clobber_test
    pic
    pod2man
    texi2html
    thumb
    valgrind_backtrace
    xmm_clobber_test
"

THREADS_LIST="
    pthreads
    w32threads
"

ATOMICS_LIST="
    atomics_gcc
    atomics_suncc
    atomics_win32
"

ARCH_LIST="
    aarch64
    alpha
    arm
    avr32
    avr32_ap
    avr32_uc
    bfin
    ia64
    m68k
    mips
    mips64
    parisc
    ppc
    ppc64
    s390
    sh4
    sparc
    sparc64
    tilegx
    tilepro
    tomi
    x86
    x86_32
    x86_64
"

ARCH_EXT_LIST_ARM="
    armv5te
    armv6
    armv6t2
    armv8
    neon
    vfp
    vfpv3
"

ARCH_EXT_LIST_X86_SIMD="
    amd3dnow
    amd3dnowext
    avx
    avx2
    fma3
    fma4
    mmx
    mmxext
    sse
    sse2
    sse3
    sse4
    sse42
    ssse3
    xop
"

ARCH_EXT_LIST_PPC="
    altivec
    dcbzl
    ldbrx
    power8
    ppc4xx
    vsx
"

ARCH_EXT_LIST_X86="
    $ARCH_EXT_LIST_X86_SIMD
    cpunop
    i686
"

ARCH_EXT_LIST_MIPS="
    loongson
    mips32r1
    mips64r1
    mips32r2
    mips64r2
    mips32r6
    mips64r6
"

ARCH_EXT_LIST="
    $ARCH_EXT_LIST_ARM
    $ARCH_EXT_LIST_MIPS
    $ARCH_EXT_LIST_PPC
    $ARCH_EXT_LIST_X86
    vis
"

ARCH_FEATURES="
    aligned_stack
    fast_64bit
    fast_clz
    fast_cmov
    local_aligned_8
    local_aligned_16
    simd_align_16
"

BUILTIN_LIST="
    atomic_cas_ptr
    machine_rw_barrier
    MemoryBarrier
    mm_empty
    rdtsc
    sync_val_compare_and_swap
"
HAVE_LIST_CMDLINE="
    inline_asm
    symver
    yasm
"

HAVE_LIST_PUB="
    bigendian
    fast_unaligned
"

HEADERS_LIST="
    AVFoundation_AVFoundation_h
    alsa_asoundlib_h
    altivec_h
    arpa_inet_h
    cdio_paranoia_h
    cdio_paranoia_paranoia_h
    dev_bktr_ioctl_bt848_h
    dev_bktr_ioctl_meteor_h
    dev_ic_bt8xx_h
    dev_video_bktr_ioctl_bt848_h
    dev_video_meteor_ioctl_meteor_h
    direct_h
    dlfcn_h
    d3d11_h
    dxva_h
    gsm_h
    io_h
    mach_mach_time_h
    machine_ioctl_bt848_h
    machine_ioctl_meteor_h
    malloc_h
    poll_h
    sndio_h
    soundcard_h
    sys_mman_h
    sys_param_h
    sys_resource_h
    sys_select_h
    sys_soundcard_h
    sys_time_h
    sys_un_h
    sys_videoio_h
    unistd_h
    valgrind_valgrind_h
    windows_h
    winsock2_h
"

INTRINSICS_LIST="
    intrinsics_neon
"

MATH_FUNCS="
    atanf
    atan2f
    cbrtf
    cosf
    exp2
    exp2f
    expf
    isinf
    isnan
    ldexpf
    llrint
    llrintf
    log2
    log2f
    log10f
    lrint
    lrintf
    powf
    rint
    round
    roundf
    sinf
    trunc
    truncf
"

SYSTEM_FUNCS="
    aligned_malloc
    clock_gettime
    closesocket
    CommandLineToArgvW
    CoTaskMemFree
    CryptGenRandom
    dlopen
    fcntl
    flt_lim
    fork
    getaddrinfo
    gethrtime
    getopt
    GetProcessAffinityMask
    GetProcessMemoryInfo
    GetProcessTimes
    getrusage
    GetSystemTimeAsFileTime
    gettimeofday
    gmtime_r
    inet_aton
    isatty
    jack_port_get_latency_range
    LoadLibrary
    localtime_r
    mach_absolute_time
    MapViewOfFile
    memalign
    mkstemp
    mmap
    mprotect
    nanosleep
    posix_memalign
    sched_getaffinity
    SetConsoleTextAttribute
    setmode
    setrlimit
    Sleep
    strerror_r
    sysconf
    sysctl
    usleep
    VirtualAlloc
"

TOOLCHAIN_FEATURES="
    as_dn_directive
    as_func
    as_object_arch
    asm_mod_q
    attribute_may_alias
    attribute_packed
    ebp_available
    ebx_available
    gnu_as
    ibm_asm
    inline_asm_labels
    pragma_deprecated
    symver_asm_label
    symver_gnu_asm
    vfp_args
    xform_asm
    xmm_clobbers
"

TYPES_LIST="
    CONDITION_VARIABLE_Ptr
    socklen_t
    struct_addrinfo
    struct_group_source_req
    struct_ip_mreq_source
    struct_ipv6_mreq
    struct_pollfd
    struct_rusage_ru_maxrss
    struct_sockaddr_in6
    struct_sockaddr_sa_len
    struct_sockaddr_storage
    struct_v4l2_frmivalenum_discrete
"

HAVE_LIST="
    $ARCH_EXT_LIST
    $(add_suffix _external $ARCH_EXT_LIST)
    $(add_suffix _inline   $ARCH_EXT_LIST)
    $ARCH_FEATURES
    $ATOMICS_LIST
    $BUILTIN_LIST
    $HAVE_LIST_CMDLINE
    $HAVE_LIST_PUB
    $HEADERS_LIST
    $INTRINSICS_LIST
    $MATH_FUNCS
    $SYSTEM_FUNCS
    $THREADS_LIST
    $TOOLCHAIN_FEATURES
    $TYPES_LIST
    atomics_native
    dos_paths
    dxva2_lib
    libc_msvcrt
    libdc1394_1
    libdc1394_2
    sdl
    section_data_rel_ro
    threads
    vaapi_x11
    vdpau_x11
    xlib
"

# options emitted with CONFIG_ prefix but not available on the command line
CONFIG_EXTRA="
    aandcttables
    ac3dsp
    audio_frame_queue
    audiodsp
    blockdsp
    bswapdsp
    cabac
    dirac_parse
    dvprofile
    faandct
    faanidct
    fdctdsp
    flacdsp
    fmtconvert
    g722dsp
    gcrypt
    gmp
    golomb
    gplv3
    h263dsp
    h264chroma
    h264dsp
    h264pred
    h264qpel
    hpeldsp
    huffman
    huffyuvdsp
    huffyuvencdsp
    idctdsp
    iirfilter
    imdct15
    intrax8
    ividsp
    jpegtables
    libx262
    lgplv3
    lpc
    lzf
    me_cmp
    mpeg_er
    mpegaudio
    mpegaudiodsp
    mpegvideo
    mpegvideoenc
    mss34dsp
    pixblockdsp
    qpeldsp
    qsv
    qsvdec
    qsvenc
    rangecoder
    riffdec
    riffenc
    rtpdec
    rtpenc_chain
    rv34dsp
    sinewin
    snappy
    startcode
    texturedsp
    texturedspenc
    tpeldsp
    videodsp
    vp3dsp
    vp56dsp
    vp8dsp
    wma_freqs
    wmv2dsp
"

CMDLINE_SELECT="
    $ARCH_EXT_LIST
    $CONFIG_LIST
    $HAVE_LIST_CMDLINE
    $THREADS_LIST
    asm
    cross_compile
    debug
    extra_warnings
    logging
    lto
    optimizations
    rpath
"

PATHS_LIST="
    bindir
    datadir
    docdir
    incdir
    libdir
    mandir
    prefix
    shlibdir
"

CMDLINE_SET="
    $PATHS_LIST
    ar
    arch
    as
    build_suffix
    cc
    objcc
    cpu
    cross_prefix
    custom_allocator
    dep_cc
    env
    extra_version
    host_cc
    host_cflags
    host_ld
    host_ldflags
    host_libs
    host_os
    ld
    logfile
    malloc_prefix
    nm
    optflags
    pkg_config
    pkg_config_flags
    random_seed
    samples
    sysinclude
    sysroot
    target_exec
    target_os
    target_path
    target_samples
    toolchain
"

CMDLINE_APPEND="
    extra_cflags
    extra_objcflags
    host_cppflags
"

# code dependency declarations

# architecture extensions

armv5te_deps="arm"
armv6_deps="arm"
armv6t2_deps="arm"
armv8_deps="aarch64"
neon_deps_any="aarch64 arm"
intrinsics_neon_deps="neon"
vfp_deps_any="aarch64 arm"
vfpv3_deps="vfp"

map 'eval ${v}_inline_deps=inline_asm' $ARCH_EXT_LIST_ARM

altivec_deps="ppc"
ppc4xx_deps="ppc"
vsx_deps="altivec"
power8_deps="vsx"

cpunop_deps="i686"
x86_64_select="i686"
x86_64_suggest="fast_cmov"

amd3dnow_deps="mmx"
amd3dnowext_deps="amd3dnow"
i686_deps="x86"
mmx_deps="x86"
mmxext_deps="mmx"
sse_deps="mmxext"
sse2_deps="sse"
sse3_deps="sse2"
ssse3_deps="sse3"
sse4_deps="ssse3"
sse42_deps="sse4"
avx_deps="sse42"
xop_deps="avx"
fma3_deps="avx"
fma4_deps="avx"
avx2_deps="avx"

mmx_external_deps="yasm"
mmx_inline_deps="inline_asm"
mmx_suggest="mmx_external mmx_inline"

for ext in $(filter_out mmx $ARCH_EXT_LIST_X86_SIMD); do
    eval dep=\$${ext}_deps
    eval ${ext}_external_deps='"${dep}_external"'
    eval ${ext}_inline_deps='"${dep}_inline"'
    eval ${ext}_suggest='"${ext}_external ${ext}_inline"'
done

aligned_stack_if_any="aarch64 ppc x86"
fast_64bit_if_any="aarch64 alpha ia64 mips64 parisc64 ppc64 sparc64 x86_64"
fast_clz_if_any="aarch64 alpha avr32 mips ppc x86"
fast_unaligned_if_any="aarch64 ppc x86"
simd_align_16_if_any="altivec neon sse"

# system capabilities
symver_if_any="symver_asm_label symver_gnu_asm"
valgrind_backtrace_deps="!optimizations valgrind_valgrind_h"

# threading support
atomics_gcc_if="sync_val_compare_and_swap"
atomics_suncc_if="atomic_cas_ptr machine_rw_barrier"
atomics_win32_if="MemoryBarrier"
atomics_native_if_any="$ATOMICS_LIST"
w32threads_deps="atomics_native"
threads_if_any="$THREADS_LIST"

# subsystems
dct_select="rdft"
dirac_parse_select="golomb"
error_resilience_select="me_cmp"
faandct_deps="faan fdctdsp"
faanidct_deps="faan idctdsp"
intrax8_select="error_resilience"
mdct_select="fft"
rdft_select="fft"
me_cmp_select="fdctdsp idctdsp pixblockdsp"
mpeg_er_select="error_resilience"
mpegaudio_select="mpegaudiodsp"
mpegaudiodsp_select="dct"
mpegvideo_select="blockdsp hpeldsp idctdsp me_cmp videodsp"
mpegvideoenc_select="me_cmp mpegvideo pixblockdsp qpeldsp"
nvenc_deps_any="dlopen LoadLibrary"
nvenc_extralibs='$ldl'
qsvdec_select="qsv"
qsvenc_select="qsv"

# decoders / encoders
aac_decoder_select="imdct15 mdct sinewin"
aac_encoder_select="audio_frame_queue iirfilter mdct sinewin"
aac_latm_decoder_select="aac_decoder aac_latm_parser"
ac3_decoder_select="ac3_parser ac3dsp bswapdsp fmtconvert mdct"
ac3_encoder_select="ac3dsp audiodsp mdct me_cmp"
ac3_fixed_encoder_select="ac3dsp audiodsp mdct me_cmp"
adpcm_g722_decoder_select="g722dsp"
adpcm_g722_encoder_select="g722dsp"
aic_decoder_select="golomb idctdsp"
alac_encoder_select="lpc"
als_decoder_select="bswapdsp"
amrnb_decoder_select="lsp"
amrwb_decoder_select="lsp"
amv_decoder_select="sp5x_decoder"
ape_decoder_select="bswapdsp"
asv1_decoder_select="blockdsp bswapdsp idctdsp"
asv1_encoder_select="bswapdsp fdctdsp pixblockdsp"
asv2_decoder_select="blockdsp bswapdsp idctdsp"
asv2_encoder_select="bswapdsp fdctdsp pixblockdsp"
atrac1_decoder_select="mdct sinewin"
atrac3_decoder_select="mdct"
atrac3p_decoder_select="mdct sinewin"
bink_decoder_select="blockdsp hpeldsp"
binkaudio_dct_decoder_select="mdct rdft dct sinewin wma_freqs"
binkaudio_rdft_decoder_select="mdct rdft sinewin wma_freqs"
cavs_decoder_select="blockdsp golomb h264chroma idctdsp qpeldsp videodsp"
cllc_decoder_select="bswapdsp"
comfortnoise_encoder_select="lpc"
cook_decoder_select="audiodsp mdct sinewin"
cscd_decoder_select="lzo"
cscd_decoder_suggest="zlib"
dca_decoder_select="fmtconvert mdct"
dds_decoder_select="texturedsp"
dnxhd_decoder_select="blockdsp idctdsp"
dnxhd_encoder_select="aandcttables blockdsp fdctdsp idctdsp mpegvideoenc pixblockdsp"
dvvideo_decoder_select="dvprofile idctdsp"
dvvideo_encoder_select="dvprofile fdctdsp me_cmp pixblockdsp"
dxa_decoder_deps="zlib"
dxv_decoder_select="lzf texturedsp"
eac3_decoder_select="ac3_decoder"
eac3_encoder_select="ac3_encoder"
eamad_decoder_select="aandcttables blockdsp bswapdsp idctdsp mpegvideo"
eatgq_decoder_select="aandcttables idctdsp"
eatqi_decoder_select="aandcttables blockdsp bswapdsp idctdsp mpeg1video_decoder"
exr_decoder_deps="zlib"
ffv1_decoder_select="golomb rangecoder"
ffv1_encoder_select="rangecoder"
ffvhuff_decoder_select="huffyuv_decoder"
ffvhuff_encoder_select="huffyuv_encoder"
fic_decoder_select="golomb"
flac_decoder_select="flacdsp golomb"
flac_encoder_select="bswapdsp flacdsp golomb lpc"
flashsv_decoder_deps="zlib"
flashsv_encoder_deps="zlib"
flashsv2_decoder_deps="zlib"
flv_decoder_select="h263_decoder"
flv_encoder_select="h263_encoder"
fourxm_decoder_select="blockdsp bswapdsp"
fraps_decoder_select="bswapdsp huffman"
g2m_decoder_deps="zlib"
g2m_decoder_select="blockdsp idctdsp jpegtables"
h261_decoder_select="mpeg_er mpegvideo"
h261_encoder_select="aandcttables mpegvideoenc"
h263_decoder_select="error_resilience h263_parser h263dsp mpeg_er mpegvideo qpeldsp"
h263_encoder_select="aandcttables h263dsp mpegvideoenc"
h263i_decoder_select="h263_decoder"
h263p_encoder_select="h263_encoder"
h264_decoder_select="cabac golomb h264chroma h264dsp h264pred h264qpel startcode videodsp"
h264_decoder_suggest="error_resilience"
h264_nvenc_encoder_deps="nvenc"
h264_qsv_decoder_deps="libmfx"
h264_qsv_decoder_select="h264_mp4toannexb_bsf h264_parser qsvdec h264_qsv_hwaccel"
h264_qsv_encoder_deps="libmfx"
h264_qsv_encoder_select="qsvenc"
hap_decoder_select="snappy texturedsp"
hap_encoder_deps="libsnappy"
hap_encoder_select="texturedspenc"
hevc_decoder_select="bswapdsp cabac golomb videodsp"
hevc_nvenc_encoder_deps="nvenc"
hevc_qsv_encoder_deps="libmfx"
hevc_qsv_decoder_deps="libmfx"
hevc_qsv_decoder_select="hevc_mp4toannexb_bsf hevc_parser qsvdec hevc_qsv_hwaccel"
hevc_qsv_encoder_select="qsvenc"
huffyuv_decoder_select="bswapdsp huffyuvdsp"
huffyuv_encoder_select="bswapdsp huffman huffyuvencdsp"
iac_decoder_select="imc_decoder"
imc_decoder_select="bswapdsp fft mdct sinewin"
indeo3_decoder_select="hpeldsp"
indeo4_decoder_select="ividsp"
indeo5_decoder_select="ividsp"
interplay_video_decoder_select="hpeldsp"
jpegls_decoder_select="golomb mjpeg_decoder"
jpegls_encoder_select="golomb"
jv_decoder_select="blockdsp"
lagarith_decoder_select="huffyuvdsp"
ljpeg_encoder_select="aandcttables idctdsp jpegtables"
loco_decoder_select="golomb"
mdec_decoder_select="blockdsp idctdsp mpegvideo"
metasound_decoder_select="lsp mdct sinewin"
mimic_decoder_select="blockdsp bswapdsp hpeldsp idctdsp"
mjpeg_decoder_select="blockdsp hpeldsp idctdsp jpegtables"
mjpeg_encoder_select="aandcttables jpegtables mpegvideoenc"
mjpegb_decoder_select="mjpeg_decoder"
mlp_decoder_select="mlp_parser"
motionpixels_decoder_select="bswapdsp"
mp1_decoder_select="mpegaudio"
mp1float_decoder_select="mpegaudio"
mp2_decoder_select="mpegaudio"
mp2float_decoder_select="mpegaudio"
mp3_decoder_select="mpegaudio"
mp3adu_decoder_select="mpegaudio"
mp3adufloat_decoder_select="mpegaudio"
mp3float_decoder_select="mpegaudio"
mp3on4_decoder_select="mpegaudio"
mp3on4float_decoder_select="mpegaudio"
mpc7_decoder_select="bswapdsp mpegaudiodsp"
mpc8_decoder_select="mpegaudiodsp"
mpeg_xvmc_decoder_deps="X11_extensions_XvMClib_h"
mpeg_xvmc_decoder_select="mpeg2video_decoder"
mpeg1video_decoder_select="error_resilience mpeg_er mpegvideo"
mpeg1video_encoder_select="aandcttables mpegvideoenc"
mpeg2video_decoder_select="error_resilience mpeg_er mpegvideo"
mpeg2video_encoder_select="aandcttables mpegvideoenc"
mpeg2_qsv_decoder_deps="libmfx"
mpeg2_qsv_decoder_select="qsvdec mpeg2_qsv_hwaccel mpegvideo_parser"
mpeg2_qsv_encoder_deps="libmfx"
mpeg2_qsv_encoder_select="qsvenc"
mpeg4_decoder_select="h263_decoder mpeg4video_parser"
mpeg4_encoder_select="h263_encoder"
msa1_decoder_select="mss34dsp"
msmpeg4v1_decoder_select="h263_decoder"
msmpeg4v2_decoder_select="h263_decoder"
msmpeg4v2_encoder_select="h263_encoder"
msmpeg4v3_decoder_select="h263_decoder"
msmpeg4v3_encoder_select="h263_encoder"
mss2_decoder_select="error_resilience mpeg_er qpeldsp vc1_decoder"
mts2_decoder_select="mss34dsp"
mxpeg_decoder_select="mjpeg_decoder"
nellymoser_decoder_select="mdct sinewin"
nellymoser_encoder_select="audio_frame_queue mdct sinewin"
nuv_decoder_select="idctdsp lzo"
nvenc_h264_encoder_deps="nvenc"
nvenc_hevc_encoder_deps="nvenc"
on2avc_decoder_select="mdct"
opus_decoder_deps="avresample"
opus_decoder_select="imdct15"
png_decoder_deps="zlib"
png_encoder_deps="zlib"
png_encoder_select="huffyuvencdsp"
prores_decoder_select="idctdsp"
prores_encoder_select="fdctdsp"
qcelp_decoder_select="lsp"
qdm2_decoder_select="mdct rdft mpegaudiodsp"
ra_144_encoder_select="audio_frame_queue lpc"
ralf_decoder_select="golomb"
rscc_decoder_deps="zlib"
rv10_decoder_select="error_resilience h263_decoder h263dsp mpeg_er"
rv10_encoder_select="h263_encoder"
rv20_decoder_select="error_resilience h263_decoder h263dsp mpeg_er"
rv20_encoder_select="h263_encoder"
rv30_decoder_select="error_resilience golomb h264chroma h264pred h264qpel mpeg_er mpegvideo rv34dsp videodsp"
rv40_decoder_select="error_resilience golomb h264chroma h264pred h264qpel mpeg_er mpegvideo rv34dsp videodsp"
screenpresso_decoder_deps="zlib"
shorten_decoder_select="golomb"
sipr_decoder_select="lsp"
sp5x_decoder_select="mjpeg_decoder"
svq1_decoder_select="hpeldsp"
svq1_encoder_select="aandcttables hpeldsp me_cmp mpegvideoenc"
svq3_decoder_select="h264_decoder hpeldsp tpeldsp"
svq3_decoder_suggest="zlib"
tak_decoder_select="audiodsp"
tdsc_decoder_deps="zlib"
tdsc_decoder_select="mjpeg_decoder"
theora_decoder_select="vp3_decoder"
thp_decoder_select="mjpeg_decoder"
tiff_decoder_suggest="zlib"
tiff_encoder_suggest="zlib"
truehd_decoder_select="mlp_decoder"
truemotion2_decoder_select="bswapdsp"
truespeech_decoder_select="bswapdsp"
tscc_decoder_deps="zlib"
txd_decoder_select="texturedsp"
twinvq_decoder_select="mdct lsp sinewin"
utvideo_decoder_select="bswapdsp"
utvideo_encoder_select="bswapdsp huffman huffyuvencdsp"
vble_decoder_select="huffyuvdsp"
vc1_decoder_select="blockdsp error_resilience h263_decoder h264chroma h264qpel intrax8 mpeg_er qpeldsp startcode"
vc1image_decoder_select="vc1_decoder"
vorbis_decoder_select="mdct"
vorbis_encoder_select="mdct"
vp3_decoder_select="hpeldsp vp3dsp videodsp"
vp5_decoder_select="h264chroma hpeldsp videodsp vp3dsp vp56dsp"
vp6_decoder_select="h264chroma hpeldsp huffman videodsp vp3dsp vp56dsp"
vp6a_decoder_select="vp6_decoder"
vp6f_decoder_select="vp6_decoder"
vp7_decoder_select="h264pred videodsp vp8dsp"
vp8_decoder_select="h264pred videodsp vp8dsp"
vp9_decoder_select="videodsp"
webp_decoder_select="vp8_decoder"
wmapro_decoder_select="mdct sinewin wma_freqs"
wmav1_decoder_select="mdct sinewin wma_freqs"
wmav1_encoder_select="mdct sinewin wma_freqs"
wmav2_decoder_select="mdct sinewin wma_freqs"
wmav2_encoder_select="mdct sinewin wma_freqs"
wmavoice_decoder_select="lsp rdft dct mdct sinewin"
wmv1_decoder_select="h263_decoder"
wmv1_encoder_select="h263_encoder"
wmv2_decoder_select="blockdsp h263_decoder idctdsp intrax8 videodsp wmv2dsp"
wmv2_encoder_select="h263_encoder wmv2dsp"
wmv3_decoder_select="vc1_decoder"
wmv3image_decoder_select="wmv3_decoder"
zerocodec_decoder_deps="zlib"
zlib_decoder_deps="zlib"
zlib_encoder_deps="zlib"
zmbv_decoder_deps="zlib"
zmbv_encoder_deps="zlib"

# hardware accelerators
d3d11va_deps="d3d11_h dxva_h ID3D11VideoDecoder"
dxva2_deps="dxva2api_h DXVA2_ConfigPictureDecode"
vaapi_deps="va_va_h"
vda_deps="VideoDecodeAcceleration_VDADecoder_h pthreads"
vda_extralibs="-framework CoreFoundation -framework VideoDecodeAcceleration -framework QuartzCore"
vdpau_deps="vdpau_vdpau_h vdpau_vdpau_x11_h"

h263_vaapi_hwaccel_deps="vaapi"
h263_vaapi_hwaccel_select="h263_decoder"
h264_d3d11va_hwaccel_deps="d3d11va"
h264_d3d11va_hwaccel_select="h264_decoder"
h264_dxva2_hwaccel_deps="dxva2"
h264_dxva2_hwaccel_select="h264_decoder"
h264_mmal_decoder_deps="mmal"
h264_mmal_hwaccel_deps="mmal"
h264_mmal_decoder_select="h264_decoder"
h264_mmal_encoder_deps="mmal"
h264_qsv_hwaccel_deps="libmfx"
h264_vaapi_hwaccel_deps="vaapi"
h264_vaapi_hwaccel_select="h264_decoder"
h264_vda_hwaccel_deps="vda"
h264_vda_hwaccel_select="h264_decoder"
h264_vda_old_hwaccel_deps="vda"
h264_vda_old_hwaccel_select="h264_decoder"
h264_vdpau_hwaccel_deps="vdpau"
h264_vdpau_hwaccel_select="h264_decoder"
hevc_d3d11va_hwaccel_deps="d3d11va DXVA_PicParams_HEVC"
hevc_d3d11va_hwaccel_select="hevc_decoder"
hevc_dxva2_hwaccel_deps="dxva2 DXVA_PicParams_HEVC"
hevc_dxva2_hwaccel_select="hevc_decoder"
hevc_qsv_hwaccel_deps="libmfx"
mpeg1_vdpau_hwaccel_deps="vdpau"
mpeg1_vdpau_hwaccel_select="mpeg1video_decoder"
mpeg2_d3d11va_hwaccel_deps="d3d11va"
mpeg2_d3d11va_hwaccel_select="mpeg2video_decoder"
mpeg2_dxva2_hwaccel_deps="dxva2"
mpeg2_dxva2_hwaccel_select="mpeg2video_decoder"
mpeg2_qsv_hwaccel_deps="libmfx"
mpeg2_vaapi_hwaccel_deps="vaapi"
mpeg2_vaapi_hwaccel_select="mpeg2video_decoder"
mpeg2_vdpau_hwaccel_deps="vdpau"
mpeg2_vdpau_hwaccel_select="mpeg2video_decoder"
mpeg4_vaapi_hwaccel_deps="vaapi"
mpeg4_vaapi_hwaccel_select="mpeg4_decoder"
mpeg4_vdpau_hwaccel_deps="vdpau"
mpeg4_vdpau_hwaccel_select="mpeg4_decoder"
vc1_d3d11va_hwaccel_deps="d3d11va"
vc1_d3d11va_hwaccel_select="vc1_decoder"
vc1_dxva2_hwaccel_deps="dxva2"
vc1_dxva2_hwaccel_select="vc1_decoder"
vc1_vaapi_hwaccel_deps="vaapi"
vc1_vaapi_hwaccel_select="vc1_decoder"
vc1_vdpau_hwaccel_deps="vdpau"
vc1_vdpau_hwaccel_select="vc1_decoder"
wmv3_d3d11va_hwaccel_select="vc1_d3d11va_hwaccel"
wmv3_dxva2_hwaccel_select="vc1_dxva2_hwaccel"
wmv3_vaapi_hwaccel_select="vc1_vaapi_hwaccel"
wmv3_vdpau_hwaccel_select="vc1_vdpau_hwaccel"

# parsers
h264_parser_select="h264_decoder"
hevc_parser_select="golomb"
mpegvideo_parser_select="mpegvideo"
mpeg4video_parser_select="error_resilience h263dsp mpeg_er mpegvideo qpeldsp"
vc1_parser_select="mpegvideo startcode vc1_decoder"

# bitstream_filters
mjpeg2jpeg_bsf_select="jpegtables"

# external libraries
libdcadec_decoder_deps="libdcadec"
libfaac_encoder_deps="libfaac"
libfaac_encoder_select="audio_frame_queue"
libfdk_aac_decoder_deps="libfdk_aac"
libfdk_aac_encoder_deps="libfdk_aac"
libfdk_aac_encoder_select="audio_frame_queue"
libgsm_decoder_deps="libgsm"
libgsm_encoder_deps="libgsm"
libgsm_ms_decoder_deps="libgsm"
libgsm_ms_encoder_deps="libgsm"
libilbc_decoder_deps="libilbc"
libilbc_encoder_deps="libilbc"
libkvazaar_encoder_deps="libkvazaar"
libmp3lame_encoder_deps="libmp3lame"
libmp3lame_encoder_select="audio_frame_queue"
libopencore_amrnb_decoder_deps="libopencore_amrnb"
libopencore_amrnb_encoder_deps="libopencore_amrnb"
libopencore_amrnb_encoder_select="audio_frame_queue"
libopencore_amrwb_decoder_deps="libopencore_amrwb"
libopenh264_encoder_deps="libopenh264"
libopenjpeg_decoder_deps="libopenjpeg"
libopenjpeg_encoder_deps="libopenjpeg"
libopus_decoder_deps="libopus"
libopus_encoder_deps="libopus"
libopus_encoder_select="audio_frame_queue"
libschroedinger_decoder_deps="libschroedinger"
libschroedinger_encoder_deps="libschroedinger"
libspeex_decoder_deps="libspeex"
libspeex_encoder_deps="libspeex"
libspeex_encoder_select="audio_frame_queue"
libtheora_encoder_deps="libtheora"
libtwolame_encoder_deps="libtwolame"
libvo_aacenc_encoder_deps="libvo_aacenc"
libvo_aacenc_encoder_select="audio_frame_queue"
libvo_amrwbenc_encoder_deps="libvo_amrwbenc"
libvorbis_encoder_deps="libvorbis"
libvorbis_encoder_select="audio_frame_queue"
libvpx_vp8_decoder_deps="libvpx"
libvpx_vp8_encoder_deps="libvpx"
libvpx_vp9_decoder_deps="libvpx"
libvpx_vp9_encoder_deps="libvpx"
libwavpack_encoder_deps="libwavpack"
libwebp_encoder_deps="libwebp"
libx262_encoder_deps="libx262"
libx264_encoder_deps="libx264"
libx265_encoder_deps="libx265"
libxavs_encoder_deps="libxavs"
libxvid_encoder_deps="libxvid"

# demuxers / muxers
ac3_demuxer_select="ac3_parser"
asf_demuxer_select="riffdec"
asf_muxer_select="riffenc"
asf_stream_muxer_select="asf_muxer"
avi_demuxer_select="riffdec"
avi_muxer_select="riffenc"
avisynth_demuxer_deps="avisynth"
avisynth_demuxer_select="riffdec"
caf_demuxer_select="riffdec"
dash_muxer_select="mp4_muxer"
dirac_demuxer_select="dirac_parser"
dv_demuxer_select="dvprofile"
dv_muxer_select="dvprofile"
dxa_demuxer_select="riffdec"
eac3_demuxer_select="ac3_parser"
f4v_muxer_select="mov_muxer"
flac_demuxer_select="flac_parser"
hds_muxer_select="flv_muxer"
hls_muxer_select="mpegts_muxer"
ipod_muxer_select="mov_muxer"
ismv_muxer_select="mov_muxer"
matroska_audio_muxer_select="matroska_muxer"
matroska_demuxer_select="riffdec"
matroska_demuxer_suggest="bzlib lzo zlib"
matroska_muxer_select="riffenc"
mmf_muxer_select="riffenc"
mov_demuxer_select="riffdec"
mov_demuxer_suggest="zlib"
mov_muxer_select="riffenc rtpenc_chain"
mp3_demuxer_select="mpegaudio_parser"
mp4_muxer_select="mov_muxer"
mpegts_muxer_select="adts_muxer latm_muxer"
mpegtsraw_demuxer_select="mpegts_demuxer"
mxf_d10_muxer_select="mxf_muxer"
nut_muxer_select="riffenc"
nuv_demuxer_select="riffdec"
oga_muxer_select="ogg_muxer"
ogg_demuxer_select="dirac_parse"
opus_muxer_select="ogg_muxer"
psp_muxer_select="mov_muxer"
rtp_demuxer_select="sdp_demuxer"
rtpdec_select="asf_demuxer jpegtables mov_demuxer mpegts_demuxer rm_demuxer rtp_protocol"
rtsp_demuxer_select="http_protocol rtpdec"
rtsp_muxer_select="rtp_muxer http_protocol rtp_protocol rtpenc_chain"
sap_demuxer_select="sdp_demuxer"
sap_muxer_select="rtp_muxer rtp_protocol rtpenc_chain"
sdp_demuxer_select="rtpdec"
smoothstreaming_muxer_select="ismv_muxer"
spdif_muxer_select="aac_parser"
spx_muxer_select="ogg_muxer"
swf_demuxer_suggest="zlib"
tak_demuxer_select="tak_parser"
tg2_muxer_select="mov_muxer"
tgp_muxer_select="mov_muxer"
w64_demuxer_select="wav_demuxer"
wav_demuxer_select="riffdec"
wav_muxer_select="riffenc"
webm_muxer_select="riffenc"
webm_muxer_suggest="libopus_encoder libvorbis_encoder libvpx_vp8_encoder libvpx_vp9_encoder"
wtv_demuxer_select="riffdec"
xmv_demuxer_select="riffdec"
xwma_demuxer_select="riffdec"

# indevs / outdevs
alsa_indev_deps="alsa_asoundlib_h snd_pcm_htimestamp"
alsa_outdev_deps="alsa_asoundlib_h"
avfoundation_indev_deps="AVFoundation_AVFoundation_h"
bktr_indev_deps_any="dev_bktr_ioctl_bt848_h machine_ioctl_bt848_h dev_video_bktr_ioctl_bt848_h dev_ic_bt8xx_h"
dv1394_indev_deps="dv1394"
dv1394_indev_select="dv_demuxer"
fbdev_indev_deps="linux_fb_h"
jack_indev_deps="jack_jack_h pthreads"
libcdio_indev_deps="libcdio"
libdc1394_indev_deps="libdc1394"
oss_indev_deps_any="soundcard_h sys_soundcard_h"
oss_outdev_deps_any="soundcard_h sys_soundcard_h"
pulse_indev_deps="libpulse"
sndio_indev_deps="sndio_h"
sndio_outdev_deps="sndio_h"
v4l2_indev_deps_any="linux_videodev2_h sys_videoio_h"
vfwcap_indev_deps="capCreateCaptureWindow vfwcap_defines"
vfwcap_indev_extralibs="-lavicap32"
x11grab_indev_deps="x11grab"
x11grab_xcb_indev_deps="libxcb"

# protocols
ffrtmpcrypt_protocol_deps="!librtmp_protocol"
ffrtmpcrypt_protocol_deps_any="gcrypt gmp openssl"
ffrtmpcrypt_protocol_select="tcp_protocol"
ffrtmphttp_protocol_deps="!librtmp_protocol"
ffrtmphttp_protocol_select="http_protocol"
gopher_protocol_select="network"
http_protocol_select="tcp_protocol"
httpproxy_protocol_select="tcp_protocol"
https_protocol_select="tls_protocol"
icecast_protocol_select="http_protocol"
librtmp_protocol_deps="librtmp"
librtmpe_protocol_deps="librtmp"
librtmps_protocol_deps="librtmp"
librtmpt_protocol_deps="librtmp"
librtmpte_protocol_deps="librtmp"
mmsh_protocol_select="http_protocol"
mmst_protocol_select="network"
rtmp_protocol_deps="!librtmp_protocol"
rtmp_protocol_select="tcp_protocol"
rtmpe_protocol_select="ffrtmpcrypt_protocol"
rtmps_protocol_deps="!librtmp_protocol"
rtmps_protocol_select="tls_protocol"
rtmpt_protocol_select="ffrtmphttp_protocol"
rtmpte_protocol_select="ffrtmpcrypt_protocol ffrtmphttp_protocol"
rtmpts_protocol_select="ffrtmphttp_protocol https_protocol"
rtp_protocol_select="udp_protocol"
sctp_protocol_deps="struct_sctp_event_subscribe"
sctp_protocol_select="network"
srtp_protocol_select="rtp_protocol"
tcp_protocol_select="network"
tls_gnutls_protocol_deps="gnutls"
tls_gnutls_protocol_select="tcp_protocol"
tls_openssl_protocol_deps="openssl !tls_gnutls_protocol"
tls_openssl_protocol_select="tcp_protocol"
tls_protocol_select_any="tls_gnutls_protocol tls_openssl_protocol"
udp_protocol_select="network"
unix_protocol_deps="sys_un_h"
unix_protocol_select="network"

# filters
blackframe_filter_deps="gpl"
boxblur_filter_deps="gpl"
bs2b_filter_deps="libbs2b"
cropdetect_filter_deps="gpl"
delogo_filter_deps="gpl"
drawtext_filter_deps="libfreetype"
frei0r_filter_deps="frei0r dlopen"
frei0r_filter_extralibs='$ldl'
frei0r_src_filter_deps="frei0r dlopen"
frei0r_src_filter_extralibs='$ldl'
hqdn3d_filter_deps="gpl"
interlace_filter_deps="gpl"
ocv_filter_deps="libopencv"
resample_filter_deps="avresample"
scale_filter_deps="swscale"

# examples
avcodec_example_deps="avcodec avutil"
filter_audio_example_deps="avfilter avutil"
metadata_example_deps="avformat avutil"
output_example_deps="avcodec avformat avutil swscale"
qsvdec_example_deps="avcodec avutil libmfx h264_qsv_decoder vaapi_x11"
transcode_aac_example_deps="avcodec avformat avresample"

# libraries, in linking order
avcodec_deps="avutil"
avdevice_deps="avformat avcodec avutil"
avfilter_deps="avutil"
avformat_deps="avcodec avutil"
avresample_deps="avutil"
swscale_deps="avutil"

# programs
avconv_deps="avcodec avfilter avformat avresample swscale"
avconv_select="aformat_filter anull_filter asyncts_filter atrim_filter format_filter
               fps_filter null_filter resample_filter scale_filter
               setpts_filter trim_filter"
avplay_deps="avcodec avformat avresample swscale sdl"
avplay_libs='$sdl_libs'
avplay_select="rdft transpose_filter hflip_filter vflip_filter"
avprobe_deps="avcodec avformat"

# documentation
pod2man_deps="doc"
texi2html_deps="doc"

# default parameters

logfile="config.log"

# installation paths
prefix_default="/usr/local"
bindir_default='${prefix}/bin'
datadir_default='${prefix}/share/avconv'
docdir_default='${prefix}/share/doc/libav'
incdir_default='${prefix}/include'
libdir_default='${prefix}/lib'
mandir_default='${prefix}/share/man'
shlibdir_default="$libdir_default"

# toolchain
ar_default="ar"
cc_default="gcc"
host_cc_default="gcc"
cp_f="cp -f"
ln_s="ln -s -f"
nm_default="nm -g"
objformat="elf"
pkg_config_default=pkg-config
ranlib="ranlib"
strip="strip"
yasmexe="yasm"

# machine
arch_default=$(uname -m)
cpu="generic"
intrinsics="none"

# OS
target_os_default=$(tolower $(uname -s))
host_os=$target_os_default

# configurable options
enable $EXAMPLE_LIST $LIBRARY_LIST $PROGRAM_LIST

enable asm
enable debug
enable doc
enable faan faandct faanidct
enable optimizations
enable safe_bitstream_reader
enable static
enable swscale_alpha
enable valgrind_backtrace

# By default, enable only those hwaccels that have no external dependencies.
enable d3d11va dxva2 vda vdpau

# build settings
SHFLAGS='-shared -Wl,-soname,$$(@F)'
LIBPREF="lib"
LIBSUF=".a"
FULLNAME='$(NAME)$(BUILDSUF)'
LIBNAME='$(LIBPREF)$(FULLNAME)$(LIBSUF)'
SLIBPREF="lib"
SLIBSUF=".so"
SLIBNAME='$(SLIBPREF)$(FULLNAME)$(SLIBSUF)'
SLIBNAME_WITH_VERSION='$(SLIBNAME).$(LIBVERSION)'
SLIBNAME_WITH_MAJOR='$(SLIBNAME).$(LIBMAJOR)'
LIB_INSTALL_EXTRA_CMD='$$(RANLIB) "$(LIBDIR)/$(LIBNAME)"'
SLIB_INSTALL_NAME='$(SLIBNAME_WITH_VERSION)'
SLIB_INSTALL_LINKS='$(SLIBNAME_WITH_MAJOR) $(SLIBNAME)'

asflags_filter=echo
cflags_filter=echo
ldflags_filter=echo

AS_C='-c'
AS_O='-o $@'
CC_C='-c'
CC_E='-E -o $@'
CC_O='-o $@'
OBJCC_C='-c'
OBJCC_E='-E -o $@'
OBJCC_O='-o $@'
LD_O='-o $@'
LD_LIB='-l%'
LD_PATH='-L'
HOSTCC_C='-c'
HOSTCC_E='-E -o $@'
HOSTCC_O='-o $@'
HOSTLD_O='-o $@'

host_libs='-lm'
host_cflags_filter=echo
host_ldflags_filter=echo

target_path='$(CURDIR)'

# since the object filename is not given with the -MM flag, the compiler
# is only able to print the basename, and we must add the path ourselves
DEPCMD='$(DEP$(1)) $(DEP$(1)FLAGS) $($(1)DEP_FLAGS) $< | sed -e "/^\#.*/d" -e "s,^[[:space:]]*$(*F)\\.o,$(@D)/$(*F).o," > $(@:.o=.d)'
DEPFLAGS='-MM'

# find source path
if test -f configure; then
    source_path=.
else
    source_path=$(cd $(dirname "$0"); pwd)
    echo "$source_path" | grep -q '[[:blank:]]' &&
        die "Out of tree builds are impossible with whitespace in source path."
    test -e "$source_path/config.h" &&
        die "Out of tree builds are impossible with config.h in source dir."
fi

for v in "$@"; do
    r=${v#*=}
    l=${v%"$r"}
    r=$(sh_quote "$r")
    LIBAV_CONFIGURATION="${LIBAV_CONFIGURATION# } ${l}${r}"
done

find_things(){
    thing=$1
    pattern=$2
    file=$source_path/$3
    sed -n "s/^[^#]*$pattern.*([^,]*, *\([^,]*\)\(,.*\)*).*/\1_$thing/p" "$file"
}

ENCODER_LIST=$(find_things  encoder  ENC      libavcodec/allcodecs.c)
DECODER_LIST=$(find_things  decoder  DEC      libavcodec/allcodecs.c)
HWACCEL_LIST=$(find_things  hwaccel  HWACCEL  libavcodec/allcodecs.c)
PARSER_LIST=$(find_things   parser   PARSER   libavcodec/allcodecs.c)
BSF_LIST=$(find_things      bsf      BSF      libavcodec/allcodecs.c)
MUXER_LIST=$(find_things    muxer    _MUX     libavformat/allformats.c)
DEMUXER_LIST=$(find_things  demuxer  DEMUX    libavformat/allformats.c)
OUTDEV_LIST=$(find_things   outdev   OUTDEV   libavdevice/alldevices.c)
INDEV_LIST=$(find_things    indev    _IN      libavdevice/alldevices.c)
PROTOCOL_LIST=$(find_things protocol PROTOCOL libavformat/allformats.c)
FILTER_LIST=$(find_things   filter   FILTER   libavfilter/allfilters.c)

ALL_COMPONENTS="
    $BSF_LIST
    $DECODER_LIST
    $DEMUXER_LIST
    $ENCODER_LIST
    $FILTER_LIST
    $HWACCEL_LIST
    $INDEV_LIST
    $MUXER_LIST
    $OUTDEV_LIST
    $PARSER_LIST
    $PROTOCOL_LIST
"

enable $ARCH_EXT_LIST

die_unknown(){
    echo "Unknown option \"$1\"."
    echo "See $0 --help for available options."
    exit 1
}

print_3_columns() {
    printf "%-25s %-25s %-25s\n" $(cat | tr ' ' '\n' | sort)
}

show_list() {
    suffix=_$1
    shift
    echo $* | sed s/$suffix//g | print_3_columns
    exit 0
}

rand_list(){
    IFS=', '
    set -- $*
    unset IFS
    for thing; do
        comp=${thing%:*}
        prob=${thing#$comp}
        prob=${prob#:}
        is_in ${comp} $COMPONENT_LIST && eval comp=\$$(toupper ${comp%s})_LIST
        echo "prob ${prob:-0.5}"
        printf '%s\n' $comp
    done
}

do_random(){
    action=$1
    shift
    random_seed=$(awk "BEGIN { srand($random_seed); print srand() }")
    $action $(rand_list "$@" | awk "BEGIN { srand($random_seed) } \$1 == \"prob\" { prob = \$2; next } rand() < prob { print }")
}

for opt do
    optval="${opt#*=}"
    case "$opt" in
        --extra-ldflags=*)
            add_ldflags $optval
        ;;
        --extra-ldexeflags=*)
            add_ldexeflags $optval
        ;;
        --extra-libs=*)
            add_extralibs $optval
        ;;
        --disable-devices)
            disable $INDEV_LIST $OUTDEV_LIST
        ;;
        --enable-debug=*)
            debuglevel="$optval"
        ;;
        --disable-programs)
            disable $PROGRAM_LIST
        ;;
        --disable-everything)
            map 'eval disable \${$(toupper ${v%s})_LIST}' $COMPONENT_LIST
        ;;
        --disable-all)
            map 'eval disable \${$(toupper ${v%s})_LIST}' $COMPONENT_LIST
            disable $LIBRARY_LIST $PROGRAM_LIST doc
        ;;
        --enable-random|--disable-random)
            action=${opt%%-random}
            do_random ${action#--} $COMPONENT_LIST
        ;;
        --enable-random=*|--disable-random=*)
            action=${opt%%-random=*}
            do_random ${action#--} $optval
        ;;
        --enable-*=*|--disable-*=*)
            eval $(echo "${opt%%=*}" | sed 's/--/action=/;s/-/ thing=/')
            is_in "${thing}s" $COMPONENT_LIST || die_unknown "$opt"
            eval list=\$$(toupper $thing)_LIST
            name=$(echo "${optval}" | sed "s/,/_${thing}|/g")_${thing}
            test $action = enable && action="request"
            $action $(filter "$name" $list)
        ;;
        --enable-avserver|--disable-avserver*)
            warn "avserver has been removed, the ${opt} option is only"\
                 "provided for compatibility and will be removed in the future"
        ;;
        --enable-?*|--disable-?*)
            eval $(echo "$opt" | sed 's/--/action=/;s/-/ option=/;s/-/_/g')
            if is_in $option $COMPONENT_LIST; then
                eval $action \$$(toupper ${option%s})_LIST
            elif is_in $option $CMDLINE_SELECT; then
                $action $option
            else
                die_unknown $opt
            fi
        ;;
        --list-*)
            NAME="${opt#--list-}"
            is_in $NAME $COMPONENT_LIST || die_unknown $opt
            NAME=${NAME%s}
            eval show_list $NAME \$$(toupper $NAME)_LIST
        ;;
        --help|-h) show_help
        ;;
        *)
            optname="${opt%%=*}"
            optname="${optname#--}"
            optname=$(echo "$optname" | sed 's/-/_/g')
            if is_in $optname $CMDLINE_SET; then
                eval $optname='$optval'
            elif is_in $optname $CMDLINE_APPEND; then
                append $optname "$optval"
            else
                die_unknown $opt
            fi
        ;;
    esac
done

for e in $env; do
    eval "export $e"
done

disabled logging && logfile=/dev/null

# Disable all the library-specific components if the library itself
# is disabled, see AVCODEC_LIST and following _LIST variables.

disable_components(){
    disabled ${1} && disable_weak $(
        eval components="\$$(toupper ${1})_COMPONENTS"
        map 'eval echo \${$(toupper ${v%s})_LIST}' $components
    )
}

map 'disable_components $v' $LIBRARY_LIST

# Mark components that had not been enabled/disabled explicitly
# as enabled

for n in $COMPONENT_LIST; do
    v=$(toupper ${n%s})_LIST
    eval enable_weak \$$v
    eval ${n}_if_any="\$$v"
done

# Make so that disabled libraries are enabled if a component
# of them is requested

for n in $LIBRARY_LIST; do
    v=$(toupper ${n})_COMPONENTS
    eval ${n}_if_any="\$$v"
done

echo "# $0 $LIBAV_CONFIGURATION" > $logfile
set >> $logfile

case "$toolchain" in
    clang-asan)
        cc_default="clang"
        add_cflags  -fsanitize=address
        add_ldflags -fsanitize=address
    ;;
    clang-tsan)
        cc_default="clang"
        add_cflags  -fsanitize=thread -pie
        add_ldflags -fsanitize=thread -pie
    ;;
    clang-usan)
        cc_default="clang"
        add_cflags  -fsanitize=undefined -O1
        add_ldflags -fsanitize=undefined
    ;;
    gcc-asan)
        cc_default="gcc"
        add_cflags  -fsanitize=address
        add_ldflags -fsanitize=address
    ;;
    gcc-tsan)
        cc_default="gcc"
        add_cflags  -fsanitize=thread -pie -fPIC
        add_ldflags -fsanitize=thread -pie -fPIC
    ;;
    gcc-usan)
        cc_default="gcc"
        add_cflags  -fsanitize=undefined
        add_ldflags -fsanitize=undefined
    ;;
    valgrind-massif)
        target_exec_default="valgrind"
        target_exec_args="--alloc-fn=av_malloc --alloc-fn=av_mallocz"
    ;;
    valgrind-memcheck)
        target_exec_default="valgrind"
        target_exec_args="--track-origins=yes --leak-check=full"
    ;;
    msvc)
        # Check whether the current MSVC version needs the C99 converter.
        # From MSVC 2013 (compiler major version 18) onwards, it does actually
        # support enough of C99 to build libav. Default to the new
        # behaviour if the regexp was unable to match anything, since this
        # successfully parses the version number of existing supported
        # versions that require the converter (MSVC 2010 and 2012).
        cl_major_ver=$(cl 2>&1 | sed -n 's/.*Version \([[:digit:]]\{1,\}\)\..*/\1/p')
        if [ -z "$cl_major_ver" ] || [ $cl_major_ver -ge 18 ]; then
            cc_default="cl"
        else
            cc_default="c99wrap cl"
        fi
        ld_default="$source_path/compat/windows/mslink"
        nm_default="dumpbin -symbols"
        ar_default="lib"
        case "$arch" in
        arm*)
            as_default="armasm"
            ;;
        esac
        target_os_default="win32"
        # Use a relative path for TMPDIR. This makes sure all the
        # ffconf temp files are written with a relative path, avoiding
        # issues with msys/win32 path conversion for MSVC parameters
        # such as -Fo<file> or -out:<file>.
        TMPDIR=.
    ;;
    icl)
        cc_default="icl"
        ld_default="xilink"
        nm_default="dumpbin -symbols"
        ar_default="xilib"
        target_os_default="win32"
        TMPDIR=.
    ;;
    gcov)
        add_cflags  -fprofile-arcs -ftest-coverage
        add_ldflags -fprofile-arcs -ftest-coverage
    ;;
    hardened)
        add_cppflags -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2
        add_cflags   -fno-strict-overflow -fstack-protector-all
        add_ldflags  -Wl,-z,relro -Wl,-z,now
    ;;
    ?*)
        die "Unknown toolchain $toolchain"
    ;;
esac

test -n "$cross_prefix" && enable cross_compile

if enabled cross_compile; then
    test -n "$arch" && test -n "$target_os" ||
        die "Must specify target arch and OS when cross-compiling"
fi

ar_default="${cross_prefix}${ar_default}"
cc_default="${cross_prefix}${cc_default}"
occ_default="${cross_prefix}${occ_default}"
nm_default="${cross_prefix}${nm_default}"
pkg_config_default="${cross_prefix}${pkg_config_default}"
ranlib="${cross_prefix}${ranlib}"
strip="${cross_prefix}${strip}"

sysinclude_default="${sysroot}/usr/include"

set_default arch cc pkg_config sysinclude target_exec target_os
enabled cross_compile || host_cc_default=$cc
set_default host_cc

if ! $pkg_config --version >/dev/null 2>&1; then
    warn "$pkg_config not found, library detection may fail."
    pkg_config=false
fi

exesuf() {
    case $1 in
        mingw32*|win32|win64|cygwin*|*-dos|freedos|opendos|os/2*|symbian) echo .exe ;;
    esac
}

EXESUF=$(exesuf $target_os)
HOSTEXESUF=$(exesuf $host_os)

# set temporary file name
: ${TMPDIR:=$TEMPDIR}
: ${TMPDIR:=$TMP}
: ${TMPDIR:=/tmp}

if ! check_cmd mktemp -u XXXXXX; then
    # simple replacement for missing mktemp
    # NOT SAFE FOR GENERAL USE
    mktemp(){
        echo "${2%%XXX*}.${HOSTNAME}.${UID}.$$"
    }
fi

tmpfile(){
    tmp=$(mktemp -u "${TMPDIR}/ffconf.XXXXXXXX")$2 &&
        (set -C; exec > $tmp) 2>/dev/null ||
        die "Unable to create temporary file in $TMPDIR."
    append TMPFILES $tmp
    eval $1=$tmp
}

trap 'rm -f -- $TMPFILES' EXIT

tmpfile TMPASM .asm
tmpfile TMPC   .c
tmpfile TMPE   $EXESUF
tmpfile TMPH   .h
tmpfile TMPO   .o
tmpfile TMPS   .S
tmpfile TMPSH  .sh
tmpfile TMPV   .ver

unset -f mktemp

chmod +x $TMPE

# make sure we can execute files in $TMPDIR
cat > $TMPSH 2>> $logfile <<EOF
#! /bin/sh
EOF
chmod +x $TMPSH >> $logfile 2>&1
if ! $TMPSH >> $logfile 2>&1; then
    cat <<EOF
Unable to create and execute files in $TMPDIR.  Set the TMPDIR environment
variable to another directory and make sure that it is not mounted noexec.
EOF
    die "Sanity test failed."
fi

armasm_flags(){
    for flag; do
        case $flag in
            # Filter out MSVC cl.exe options from cflags that shouldn't
            # be passed to gas-preprocessor
            -M[TD]*)                                            ;;
            *)                  echo $flag                      ;;
        esac
   done
}

ccc_flags(){
    for flag; do
        case $flag in
            -std=c99)           echo -c99                       ;;
            -mcpu=*)            echo -arch ${flag#*=}           ;;
            -mieee)             echo -ieee                      ;;
            -O*|-fast)          echo $flag                      ;;
            -fno-math-errno)    echo -assume nomath_errno       ;;
            -g)                 echo -g3                        ;;
            -Wall)              echo -msg_enable level2         ;;
            -Wno-pointer-sign)  echo -msg_disable ptrmismatch1  ;;
            -Wl,*)              echo $flag                      ;;
            -f*|-W*)                                            ;;
            *)                  echo $flag                      ;;
        esac
   done
}

cparser_flags(){
    for flag; do
        case $flag in
            -Wno-switch)             echo -Wno-switch-enum ;;
            -Wno-format-zero-length) ;;
            -Wdisabled-optimization) ;;
            -Wno-pointer-sign)       echo -Wno-other ;;
            *)                       echo $flag ;;
        esac
    done
}

msvc_common_flags(){
    for flag; do
        case $flag in
            # In addition to specifying certain flags under the compiler
            # specific filters, they must be specified here as well or else the
            # generic catch all at the bottom will print the original flag.
            -Wall)                ;;
            -std=c99)             ;;
            # Common flags
            -fomit-frame-pointer) ;;
            -g)                   echo -Z7 ;;
            -fno-math-errno)      ;;
            -fno-common)          ;;
            -fno-signed-zeros)    ;;
            -fPIC)                ;;
            -mthumb)              ;;
            -march=*)             ;;
            -lz)                  echo zlib.lib ;;
            -lavifil32)           echo vfw32.lib ;;
            -lavicap32)           echo vfw32.lib user32.lib ;;
            -l*)                  echo ${flag#-l}.lib ;;
            -L*)                  echo -libpath:${flag#-L} ;;
            *)                    echo $flag ;;
        esac
    done
}

msvc_flags(){
    msvc_common_flags "$@"
    for flag; do
        case $flag in
            -Wall)                echo -W4 -wd4244 -wd4127 -wd4018 -wd4389     \
                                       -wd4146 -wd4057 -wd4204 -wd4706 -wd4305 \
                                       -wd4152 -wd4324 -we4013 -wd4100 -wd4214 \
                                       -wd4273 -wd4554 -wd4701 ;;
        esac
    done
}

icl_flags(){
    msvc_common_flags "$@"
    for flag; do
        case $flag in
            # Despite what Intel's documentation says -Wall, which is supported
            # on Windows, does enable remarks so disable them here.
            -Wall)                echo $flag -Qdiag-disable:remark ;;
            -std=c99)             echo -Qstd=c99 ;;
        esac
    done
}

pgi_flags(){
    for flag; do
        case $flag in
            -flto)                echo -Mipa=fast,libopt,libinline,vestigial ;;
            -fomit-frame-pointer) echo -Mnoframe ;;
            -g)                   echo -gopt ;;
            *)                    echo $flag ;;
        esac
    done
}

suncc_flags(){
    for flag; do
        case $flag in
            -march=*|-mcpu=*)
                case "${flag#*=}" in
                    native)                   echo -xtarget=native       ;;
                    v9|niagara)               echo -xarch=sparc          ;;
                    ultrasparc)               echo -xarch=sparcvis       ;;
                    ultrasparc3|niagara2)     echo -xarch=sparcvis2      ;;
                    i586|pentium)             echo -xchip=pentium        ;;
                    i686|pentiumpro|pentium2) echo -xtarget=pentium_pro  ;;
                    pentium3*|c3-2)           echo -xtarget=pentium3     ;;
                    pentium-m)          echo -xarch=sse2 -xchip=pentium3 ;;
                    pentium4*)          echo -xtarget=pentium4           ;;
                    prescott|nocona)    echo -xarch=sse3 -xchip=pentium4 ;;
                    *-sse3)             echo -xarch=sse3                 ;;
                    core2)              echo -xarch=ssse3 -xchip=core2   ;;
                    corei7)           echo -xarch=sse4_2 -xchip=nehalem  ;;
                    corei7-avx)       echo -xarch=avx -xchip=sandybridge ;;
                    amdfam10|barcelona|bdver*) echo -xarch=sse4_1        ;;
                    athlon-4|athlon-[mx]p)     echo -xarch=ssea          ;;
                    k8|opteron|athlon64|athlon-fx)
                                               echo -xarch=sse2a         ;;
                    athlon*)                   echo -xarch=pentium_proa  ;;
                esac
                ;;
            -std=c99)             echo -xc99              ;;
            -fomit-frame-pointer) echo -xregs=frameptr    ;;
            -fPIC)                echo -KPIC -xcode=pic32 ;;
            -W*,*)                echo $flag              ;;
            -f*-*|-W*|-mimpure-text)                      ;;
            -shared)              echo -G                 ;;
            *)                    echo $flag              ;;
        esac
    done
}

tms470_flags(){
    for flag; do
        case $flag in
            -march=*|-mcpu=*)
                case "${flag#*=}" in
                    armv7-a|cortex-a*)      echo -mv=7a8 ;;
                    armv7-r|cortex-r*)      echo -mv=7r4 ;;
                    armv7-m|cortex-m*)      echo -mv=7m3 ;;
                    armv6*|arm11*)          echo -mv=6   ;;
                    armv5*e|arm[79]*e*|arm9[24]6*|arm96*|arm102[26])
                                            echo -mv=5e  ;;
                    armv4*|arm7*|arm9[24]*) echo -mv=4   ;;
                esac
                ;;
            -mfpu=neon)     echo --float_support=vfpv3 --neon ;;
            -mfpu=vfp)      echo --float_support=vfpv2        ;;
            -mfpu=vfpv3)    echo --float_support=vfpv3        ;;
            -mfpu=vfpv3-d16) echo --float_support=vfpv3d16    ;;
            -msoft-float)   echo --float_support=vfplib       ;;
            -O[0-3]|-mf=*)  echo $flag                        ;;
            -g)             echo -g -mn                       ;;
            -pds=*)         echo $flag                        ;;
            -D*|-I*)        echo $flag                        ;;
            --gcc|--abi=*)  echo $flag                        ;;
            -me)            echo $flag                        ;;
        esac
    done
}

probe_cc(){
    pfx=$1
    _cc=$2

    unset _type _ident _cc_c _cc_e _cc_o _flags _cflags
    unset _ld_o _ldflags _ld_lib _ld_path
    unset _depflags _DEPCMD _DEPFLAGS
    _flags_filter=echo

    if $_cc -v 2>&1 | grep -q '^gcc.*LLVM'; then
        _type=llvm_gcc
        gcc_extra_ver=$(expr "$($_cc --version 2>/dev/null | head -n1)" : '.*\((.*)\)')
        _ident="llvm-gcc $($_cc -dumpversion 2>/dev/null) $gcc_extra_ver"
        _depflags='-MMD -MF $(@:.o=.d) -MT $@'
        _cflags_speed='-O3'
        _cflags_size='-Os'
    elif $_cc -v 2>&1 | grep -qi ^gcc; then
        _type=gcc
        gcc_version=$($_cc --version | head -n1)
        gcc_basever=$($_cc -dumpversion)
        gcc_pkg_ver=$(expr "$gcc_version" : '[^ ]* \(([^)]*)\)')
        gcc_ext_ver=$(expr "$gcc_version" : ".*$gcc_pkg_ver $gcc_basever \\(.*\\)")
        _ident=$(cleanws "gcc $gcc_basever $gcc_pkg_ver $gcc_ext_ver")
        if ! $_cc -dumpversion | grep -q '^2\.'; then
            _depflags='-MMD -MF $(@:.o=.d) -MT $@'
        fi
        _cflags_speed='-O3'
        _cflags_size='-Os'
    elif $_cc --version 2>/dev/null | grep -q ^icc; then
        _type=icc
        _ident=$($_cc --version | head -n1)
        _depflags='-MMD'
        _cflags_speed='-O3'
        _cflags_size='-Os'
        _cflags_noopt='-O1'
    elif $_cc -v 2>&1 | grep -q xlc; then
        _type=xlc
        _ident=$($_cc -qversion 2>/dev/null | head -n1)
        _cflags_speed='-O5'
        _cflags_size='-O5 -qcompact'
    elif $_cc -V 2>/dev/null | grep -q Compaq; then
        _type=ccc
        _ident=$($_cc -V | head -n1 | cut -d' ' -f1-3)
        _DEPFLAGS='-M'
        _cflags_speed='-fast'
        _cflags_size='-O1'
        _flags_filter=ccc_flags
    elif $_cc --vsn 2>/dev/null | grep -Eq "ARM (C/C\+\+ )?Compiler"; then
        test -d "$sysroot" || die "No valid sysroot specified."
        _type=armcc
        _ident=$($_cc --vsn | grep -i build | head -n1 | sed 's/.*: //')
        armcc_conf="$PWD/armcc.conf"
        $_cc --arm_linux_configure                 \
             --arm_linux_config_file="$armcc_conf" \
             --configure_sysroot="$sysroot"        \
             --configure_cpp_headers="$sysinclude" >>$logfile 2>&1 ||
             die "Error creating armcc configuration file."
        $_cc --vsn | grep -q RVCT && armcc_opt=rvct || armcc_opt=armcc
        _flags="--arm_linux_config_file=$armcc_conf --translate_gcc"
        as_default="${cross_prefix}gcc"
        _depflags='-MMD'
        _cflags_speed='-O3'
        _cflags_size='-Os'
    elif $_cc -version 2>/dev/null | grep -Eq 'TMS470|TI ARM'; then
        _type=tms470
        _ident=$($_cc -version | head -n1 | tr -s ' ')
        _flags='--gcc --abi=eabi -me'
        _cc_e='-ppl -fe=$@'
        _cc_o='-fe=$@'
        _depflags='-ppa -ppd=$(@:.o=.d)'
        _cflags_speed='-O3 -mf=5'
        _cflags_size='-O3 -mf=2'
        _flags_filter=tms470_flags
    elif $_cc -v 2>&1 | grep -q clang; then
        _type=clang
        _ident=$($_cc --version 2>/dev/null | head -n1)
        _depflags='-MMD -MF $(@:.o=.d) -MT $@'
        _cflags_speed='-O3'
        _cflags_size='-Os'
    elif $_cc -V 2>&1 | grep -q Sun; then
        _type=suncc
        _ident=$($_cc -V 2>&1 | head -n1 | cut -d' ' -f 2-)
        _DEPCMD='$(DEP$(1)) $(DEP$(1)FLAGS) $($(1)DEP_FLAGS) $< | sed -e "1s,^.*: ,$@: ," -e "\$$!s,\$$, \\\," -e "1!s,^.*: , ," > $(@:.o=.d)'
        _DEPFLAGS='-xM1 -xc99'
        _ldflags='-std=c99'
        _cflags_speed='-O5'
        _cflags_size='-O5 -xspace'
        _flags_filter=suncc_flags
    elif $_cc -v 2>&1 | grep -q 'PathScale\|Path64'; then
        _type=pathscale
        _ident=$($_cc -v 2>&1 | head -n1 | tr -d :)
        _depflags='-MMD -MF $(@:.o=.d) -MT $@'
        _cflags_speed='-O2'
        _cflags_size='-Os'
        _flags_filter='filter_out -Wdisabled-optimization'
    elif $_cc -v 2>&1 | grep -q Open64; then
        _type=open64
        _ident=$($_cc -v 2>&1 | head -n1 | tr -d :)
        _depflags='-MMD -MF $(@:.o=.d) -MT $@'
        _cflags_speed='-O2'
        _cflags_size='-Os'
        _flags_filter='filter_out -Wdisabled-optimization|-Wtype-limits|-fno-signed-zeros'
    elif $_cc -V 2>&1 | grep -q Portland; then
        _type=pgi
        _ident="PGI $($_cc -V 2>&1 | awk '/^pgcc/ { print $2; exit }')"
        opt_common='-alias=ansi -Mdse -Mlre -Mpre'
        _cflags_speed="-O3 -Mautoinline -Munroll=c:4 $opt_common"
        _cflags_size="-O2 -Munroll=c:1 $opt_common"
        _cflags_noopt="-O1"
        _flags_filter=pgi_flags
    elif $_cc 2>&1 | grep -q 'Microsoft.*ARM.*Assembler'; then
        _type=armasm
        _ident=$($_cc | head -n1)
        # 4509: "This form of conditional instruction is deprecated"
        _flags="-nologo -ignore 4509"
        _flags_filter=armasm_flags
    elif $_cc -nologo- 2>&1 | grep -q Microsoft; then
        _type=msvc
        _ident=$($_cc 2>&1 | head -n1)
        _DEPCMD='$(DEP$(1)) $(DEP$(1)FLAGS) $($(1)DEP_FLAGS) $< 2>&1 | awk '\''/including/ { sub(/^.*file: */, ""); gsub(/\\/, "/"); if (!match($$0, / /)) print "$@:", $$0 }'\'' > $(@:.o=.d)'
        _DEPFLAGS='$(CPPFLAGS) $(CFLAGS) -showIncludes -Zs'
        _cflags_speed="-O2"
        _cflags_size="-O1"
        if $_cc -nologo- 2>&1 | grep -q Linker; then
            _ld_o='-out:$@'
        else
            _ld_o='-Fe$@'
        fi
        _cc_o='-Fo$@'
        _cc_e='-P -Fi$@'
        _flags_filter=msvc_flags
        _ld_lib='lib%.a'
        _ld_path='-libpath:'
        _flags='-nologo'
        _cflags='-D_USE_MATH_DEFINES -D_CRT_SECURE_NO_WARNINGS -D_CRT_NONSTDC_NO_WARNINGS'
    elif $_cc 2>&1 | grep -q Intel; then
        _type=icl
        _ident=$($_cc 2>&1 | head -n1)
        _depflags='-QMMD -QMF$(@:.o=.d) -QMT$@'
        # Not only is O3 broken on 13.x+ but it is slower on all previous
        # versions (tested) as well.
        _cflags_speed="-O2"
        _cflags_size="-O1 -Oi" # -O1 without -Oi miscompiles stuff
        if $_cc 2>&1 | grep -q Linker; then
            _ld_o='-out:$@'
        else
            _ld_o='-Fe$@'
        fi
        _cc_o='-Fo$@'
        _cc_e='-P'
        _flags_filter=icl_flags
        _ld_lib='lib%.a'
        _ld_path='-libpath:'
        # -Qdiag-error to make icl error when seeing certain unknown arguments
        _flags='-nologo -Qdiag-error:4044,10157'
        # -Qvec- -Qsimd- to prevent miscompilation, -GS for consistency
        # with MSVC which enables it by default.
        _cflags='-D_USE_MATH_DEFINES -Qms0 -Qvec- -Qsimd- -GS'
    elif $_cc --version 2>/dev/null | grep -q ^cparser; then
        _type=cparser
        _ident=$($_cc --version | head -n1)
        _depflags='-MMD'
        _cflags_speed='-O4'
        _cflags_size='-O2'
        _flags_filter=cparser_flags
    fi

    eval ${pfx}_type=\$_type
    eval ${pfx}_ident=\$_ident
}

set_ccvars(){
    eval ${1}_C=\${_cc_c-\${${1}_C}}
    eval ${1}_E=\${_cc_e-\${${1}_E}}
    eval ${1}_O=\${_cc_o-\${${1}_O}}

    if [ -n "$_depflags" ]; then
        eval ${1}_DEPFLAGS=\$_depflags
    else
        eval ${1}DEP=\${_DEPCMD:-\$DEPCMD}
        eval ${1}DEP_FLAGS=\${_DEPFLAGS:-\$DEPFLAGS}
        eval DEP${1}FLAGS=\$_flags
    fi
}

probe_cc cc "$cc"
cflags_filter=$_flags_filter
cflags_speed=$_cflags_speed
cflags_size=$_cflags_size
cflags_noopt=$_cflags_noopt
add_cflags $_flags $_cflags
cc_ldflags=$_ldflags
set_ccvars CC

probe_cc hostcc "$host_cc"
host_cflags_filter=$_flags_filter
add_host_cflags  $_flags $_cflags
set_ccvars HOSTCC

test -n "$cc_type" && enable $cc_type ||
    warn "Unknown C compiler $cc, unable to select optimal CFLAGS"

: ${as_default:=$cc}
: ${objcc_default:=$cc}
: ${dep_cc_default:=$cc}
: ${ld_default:=$cc}
: ${host_ld_default:=$host_cc}
set_default ar as objcc dep_cc ld host_ld

probe_cc as "$as"
asflags_filter=$_flags_filter
add_asflags $_flags $_cflags
set_ccvars AS

probe_cc objcc "$objcc"
objcflags_filter=$_flags_filter
add_objcflags $_flags $_cflags
set_ccvars OBJC

probe_cc ld "$ld"
ldflags_filter=$_flags_filter
add_ldflags $_flags $_ldflags
test "$cc_type" != "$ld_type" && add_ldflags $cc_ldflags
LD_O=${_ld_o-$LD_O}
LD_LIB=${_ld_lib-$LD_LIB}
LD_PATH=${_ld_path-$LD_PATH}

probe_cc hostld "$host_ld"
host_ldflags_filter=$_flags_filter
add_host_ldflags $_flags $_ldflags
HOSTLD_O=${_ld_o-$HOSTLD_O}

if [ -z "$CC_DEPFLAGS" ] && [ "$dep_cc" != "$cc" ]; then
    probe_cc depcc "$dep_cc"
    CCDEP=${_DEPCMD:-$DEPCMD}
    CCDEP_FLAGS=${_DEPFLAGS:=$DEPFLAGS}
    DEPCCFLAGS=$_flags
fi

if $ar 2>&1 | grep -q Microsoft; then
    arflags="-nologo"
    ar_o='-out:$@'
elif $ar 2>&1 | grep -q 'Texas Instruments'; then
    arflags="rq"
    ar_o='$@'
elif $ar 2>&1 | grep -q 'Usage: ar.*-X.*any'; then
    arflags='-Xany -r -c'
    ar_o='$@'
else
    arflags="rc"
    ar_o='$@'
fi

add_cflags $extra_cflags
add_objcflags $extra_objcflags
add_asflags $extra_cflags

if test -n "$sysroot"; then
    case "$cc_type" in
        gcc|llvm_gcc|clang)
            add_cppflags --sysroot="$sysroot"
            add_ldflags --sysroot="$sysroot"
        ;;
        tms470)
            add_cppflags -I"$sysinclude"
            add_ldflags  --sysroot="$sysroot"
        ;;
    esac
fi

if test "$cpu" = host; then
    enabled cross_compile &&
        die "--cpu=host makes no sense when cross-compiling."

    case "$cc_type" in
        gcc|llvm_gcc)
            check_native(){
                $cc $1=native -v -c -o $TMPO $TMPC >$TMPE 2>&1 || return
                sed -n "/cc1.*$1=/{
                            s/.*$1=\\([^ ]*\\).*/\\1/
                            p
                            q
                        }" $TMPE
            }
            cpu=$(check_native -march || check_native -mcpu)
        ;;
    esac

    test "${cpu:-host}" = host &&
        die "--cpu=host not supported with compiler $cc"
fi

# Deal with common $arch aliases
case "$arch" in
    aarch64|arm64)
        arch="aarch64"
    ;;
    arm*)
        arch="arm"
    ;;
    mips*|IP*)
        case "$arch" in
        *el)
            add_cppflags -EL
            add_ldflags -EL
        ;;
        *eb)
            add_cppflags -EB
            add_ldflags -EB
        ;;
        esac
        arch="mips"
    ;;
    parisc*|hppa*)
        arch="parisc"
    ;;
    "Power Macintosh"|ppc*|powerpc*)
        arch="ppc"
    ;;
    s390|s390x)
        arch="s390"
    ;;
    sh4|sh)
        arch="sh4"
    ;;
    sun4u|sparc*)
        arch="sparc"
    ;;
    tilegx|tile-gx)
        arch="tilegx"
    ;;
    i[3-6]86|i86pc|BePC|x86pc|x86_64|amd64)
        arch="x86"
    ;;
esac

is_in $arch $ARCH_LIST || warn "unknown architecture $arch"
enable $arch

# Add processor-specific flags
if enabled aarch64; then

    case $cpu in
        armv*)
            cpuflags="-march=$cpu"
        ;;
        *)
            cpuflags="-mcpu=$cpu"
        ;;
    esac

elif enabled alpha; then

    cpuflags="-mcpu=$cpu"

elif enabled arm; then

    check_arm_arch() {
        check_cpp_condition stddef.h \
            "defined __ARM_ARCH_${1}__ || defined __TARGET_ARCH_${2:-$1}" \
            $cpuflags
    }

    probe_arm_arch() {
        if   check_arm_arch 4;        then echo armv4;
        elif check_arm_arch 4T;       then echo armv4t;
        elif check_arm_arch 5;        then echo armv5;
        elif check_arm_arch 5E;       then echo armv5e;
        elif check_arm_arch 5T;       then echo armv5t;
        elif check_arm_arch 5TE;      then echo armv5te;
        elif check_arm_arch 5TEJ;     then echo armv5te;
        elif check_arm_arch 6;        then echo armv6;
        elif check_arm_arch 6J;       then echo armv6j;
        elif check_arm_arch 6K;       then echo armv6k;
        elif check_arm_arch 6Z;       then echo armv6z;
        elif check_arm_arch 6ZK;      then echo armv6zk;
        elif check_arm_arch 6T2;      then echo armv6t2;
        elif check_arm_arch 7;        then echo armv7;
        elif check_arm_arch 7A  7_A;  then echo armv7-a;
        elif check_arm_arch 7S;       then echo armv7-a;
        elif check_arm_arch 7R  7_R;  then echo armv7-r;
        elif check_arm_arch 7M  7_M;  then echo armv7-m;
        elif check_arm_arch 7EM 7E_M; then echo armv7-m;
        elif check_arm_arch 8A  8_A;  then echo armv8-a;
        fi
    }

    [ "$cpu" = generic ] && cpu=$(probe_arm_arch)

    case $cpu in
        armv*)
            cpuflags="-march=$cpu"
            subarch=$(echo $cpu | sed 's/[^a-z0-9]//g')
        ;;
        *)
            cpuflags="-mcpu=$cpu"
            case $cpu in
                cortex-a*)                               subarch=armv7a  ;;
                cortex-r*)                               subarch=armv7r  ;;
                cortex-m*)                 enable thumb; subarch=armv7m  ;;
                arm11*)                                  subarch=armv6   ;;
                arm[79]*e*|arm9[24]6*|arm96*|arm102[26]) subarch=armv5te ;;
                armv4*|arm7*|arm9[24]*)                  subarch=armv4   ;;
                *)                             subarch=$(probe_arm_arch) ;;
            esac
        ;;
    esac

    case "$subarch" in
        armv5t*)    enable fast_clz                ;;
        armv[6-8]*) enable fast_clz fast_unaligned ;;
    esac

elif enabled avr32; then

    case $cpu in
        ap7[02]0[0-2])
            subarch="avr32_ap"
            cpuflags="-mpart=$cpu"
        ;;
        ap)
            subarch="avr32_ap"
            cpuflags="-march=$cpu"
        ;;
        uc3[ab]*)
            subarch="avr32_uc"
            cpuflags="-mcpu=$cpu"
        ;;
        uc)
            subarch="avr32_uc"
            cpuflags="-march=$cpu"
        ;;
    esac

elif enabled bfin; then

    cpuflags="-mcpu=$cpu"

elif enabled mips; then

    cpuflags="-march=$cpu"

elif enabled ppc; then

    disable ldbrx

    case $(tolower $cpu) in
        601|ppc601|powerpc601)
            cpuflags="-mcpu=601"
            disable altivec
        ;;
        603*|ppc603*|powerpc603*)
            cpuflags="-mcpu=603"
            disable altivec
        ;;
        604*|ppc604*|powerpc604*)
            cpuflags="-mcpu=604"
            disable altivec
        ;;
        g3|75*|ppc75*|powerpc75*)
            cpuflags="-mcpu=750"
            disable altivec
        ;;
        g4|745*|ppc745*|powerpc745*)
            cpuflags="-mcpu=7450"
            disable vsx
        ;;
        74*|ppc74*|powerpc74*)
            cpuflags="-mcpu=7400"
            disable vsx
        ;;
        g5|970|ppc970|powerpc970)
            cpuflags="-mcpu=970"
            disable vsx
        ;;
        power[3-6]*)
            cpuflags="-mcpu=$cpu"
            disable vsx
        ;;
        power[7-8]*)
            cpuflags="-mcpu=$cpu"
            enable ldbrx
        ;;
        cell)
            cpuflags="-mcpu=cell"
            enable ldbrx
            disable vsx
        ;;
        e500mc)
            cpuflags="-mcpu=e500mc"
            disable altivec
        ;;
        e500v2)
            cpuflags="-mcpu=8548 -mhard-float -mfloat-gprs=double"
            disable altivec
            disable dcbzl
        ;;
        e500)
            cpuflags="-mcpu=8540 -mhard-float"
            disable altivec
            disable dcbzl
        ;;
    esac

elif enabled sparc; then

    case $cpu in
        cypress|f93[04]|tsc701|sparcl*|supersparc|hypersparc|niagara|v[789])
            cpuflags="-mcpu=$cpu"
        ;;
        ultrasparc*|niagara[234])
            cpuflags="-mcpu=$cpu"
        ;;
    esac

elif enabled x86; then

    case $cpu in
        i[345]86|pentium)
            cpuflags="-march=$cpu"
            disable i686
            disable mmx
        ;;
        # targets that do NOT support nopl and conditional mov (cmov)
        pentium-mmx|k6|k6-[23]|winchip-c6|winchip2|c3)
            cpuflags="-march=$cpu"
            disable i686
        ;;
        # targets that do support nopl and conditional mov (cmov)
        i686|pentiumpro|pentium[23]|pentium-m|athlon|athlon-tbird|athlon-4|athlon-[mx]p|athlon64*|k8*|opteron*|athlon-fx|core2|corei7*|amdfam10|barcelona|atom|bdver*)
            cpuflags="-march=$cpu"
            enable i686
            enable fast_cmov
        ;;
        # targets that do support conditional mov but on which it's slow
        pentium4|pentium4m|prescott|nocona)
            cpuflags="-march=$cpu"
            enable i686
            disable fast_cmov
        ;;
    esac

fi

if [ "$cpu" != generic ]; then
    add_cflags  $cpuflags
    add_asflags $cpuflags
    test "$cc_type" = "$ld_type" && add_ldflags $cpuflags
fi

# compiler sanity check
check_exec <<EOF
int main(void){ return 0; }
EOF
if test "$?" != 0; then
    echo "$cc is unable to create an executable file."
    if test -z "$cross_prefix" && ! enabled cross_compile ; then
        echo "If $cc is a cross-compiler, use the --enable-cross-compile option."
        echo "Only do this if you know what cross compiling means."
    fi
    die "C compiler test failed."
fi

add_cppflags -D_ISOC99_SOURCE
check_cflags -std=c99
check_cc -D_FILE_OFFSET_BITS=64 <<EOF && add_cppflags -D_FILE_OFFSET_BITS=64
#include <stdlib.h>
EOF
check_cc -D_LARGEFILE_SOURCE <<EOF && add_cppflags -D_LARGEFILE_SOURCE
#include <stdlib.h>
EOF

add_host_cppflags -D_ISOC99_SOURCE
check_host_cflags -std=c99
check_host_cflags -Wall
check_host_cflags -O3

check_64bit(){
    arch32=$1
    arch64=$2
    expr=$3
    check_code cc "" "int test[2*($expr) - 1]" &&
        subarch=$arch64 || subarch=$arch32
}

case "$arch" in
    aarch64|alpha|ia64)
        spic=$shared
    ;;
    mips)
        check_64bit mips mips64 '_MIPS_SIM > 1'
        spic=$shared
    ;;
    parisc)
        check_64bit parisc parisc64 'sizeof(void *) > 4'
        spic=$shared
    ;;
    ppc)
        check_64bit ppc ppc64 'sizeof(void *) > 4'
        spic=$shared
    ;;
    s390)
        check_64bit s390 s390x 'sizeof(void *) > 4'
        spic=$shared
    ;;
    sparc)
        check_64bit sparc sparc64 'sizeof(void *) > 4'
        spic=$shared
    ;;
    x86)
        check_64bit x86_32 x86_64 'sizeof(void *) > 4'
        if test "$subarch" = "x86_64"; then
            spic=$shared
        fi
    ;;
esac

enable $subarch
enabled spic && enable_weak pic

# OS specific
case $target_os in
    aix)
        SHFLAGS=-shared
        add_cppflags '-I\$(SRC_PATH)/compat/aix'
        enabled shared && add_ldflags -Wl,-brtl
        ;;
    android)
        disable symver
        enable section_data_rel_ro
        SLIB_INSTALL_NAME='$(SLIBNAME)'
        SLIB_INSTALL_LINKS=
        SHFLAGS='-shared -Wl,-soname,$(SLIBNAME)'
        ;;
    haiku)
        prefix_default="/boot/common"
        network_extralibs="-lnetwork"
        host_libs=
        ;;
    sunos)
        SHFLAGS='-shared -Wl,-h,$$(@F)'
        enabled x86 && SHFLAGS="-mimpure-text $SHFLAGS"
        network_extralibs="-lsocket -lnsl"
        # When using suncc to build, the Solaris linker will mark
        # an executable with each instruction set encountered by
        # the Solaris assembler.  As our libraries contain their own
        # guards for processor-specific code, instead suppress
        # generation of the HWCAPS ELF section on Solaris x86 only.
        enabled_all suncc x86 &&
            echo "hwcap_1 = OVERRIDE;" > mapfile &&
            add_ldflags -Wl,-M,mapfile
        nm_default='nm -P -g'
        SLIB_CREATE_DEF_CMD='$(Q)perl $(SRC_PATH)/compat/solaris/make_sunver.pl $$(filter %.ver,$$^) $(OBJS) | grep -v @ > $(SUBDIR)lib$(NAME).ver-sol2'
        ;;
    netbsd)
        disable symver
        oss_indev_extralibs="-lossaudio"
        oss_outdev_extralibs="-lossaudio"
        ;;
    openbsd|bitrig)
        disable symver
        SHFLAGS='-shared'
        SLIB_INSTALL_NAME='$(SLIBNAME).$(LIBMAJOR).$(LIBMINOR)'
        SLIB_INSTALL_LINKS=
        oss_indev_extralibs="-lossaudio"
        oss_outdev_extralibs="-lossaudio"
        ;;
    dragonfly)
        disable symver
        ;;
    freebsd)
        ;;
    bsd/os)
        add_extralibs -lpoll -lgnugetopt
        ;;
    darwin)
        enabled ppc && add_asflags -force_cpusubtype_ALL
        SHFLAGS='-dynamiclib -Wl,-single_module -Wl,-install_name,$(SHLIBDIR)/$(SLIBNAME_WITH_MAJOR),-current_version,$(LIBVERSION),-compatibility_version,$(LIBMAJOR)'
        enabled x86_32 && append SHFLAGS -Wl,-read_only_relocs,suppress
        add_ldflags -Wl,-dynamic,-search_paths_first
        SLIBSUF=".dylib"
        SLIBNAME_WITH_VERSION='$(SLIBPREF)$(FULLNAME).$(LIBVERSION)$(SLIBSUF)'
        SLIBNAME_WITH_MAJOR='$(SLIBPREF)$(FULLNAME).$(LIBMAJOR)$(SLIBSUF)'
        objformat="macho"
        enabled x86_64 && objformat="macho64"
        enabled_any pic shared ||
            { check_cflags -mdynamic-no-pic && add_asflags -mdynamic-no-pic; }
        ;;
    msys*)
        die "Native MSYS builds are discouraged, please use the MINGW environment.";
        ;;
    mingw32*)
        if test $target_os = "mingw32ce"; then
            disable network
        else
            target_os=mingw32
        fi
        LIBTARGET=i386
        if enabled x86_64; then
            LIBTARGET="i386:x86-64"
        elif enabled arm; then
            LIBTARGET=arm-wince
        fi
        check_ldflags -Wl,--nxcompat
        check_ldflags -Wl,--dynamicbase
        shlibdir_default="$bindir_default"
        SLIBPREF=""
        SLIBSUF=".dll"
        SLIBNAME_WITH_VERSION='$(SLIBPREF)$(FULLNAME)-$(LIBVERSION)$(SLIBSUF)'
        SLIBNAME_WITH_MAJOR='$(SLIBPREF)$(FULLNAME)-$(LIBMAJOR)$(SLIBSUF)'
        SLIB_EXTRA_CMD=-'sed -e "s/ @[^ ]*//" $$(@:$(SLIBSUF)=.orig.def) > $$(@:$(SLIBSUF)=.def); $(DLLTOOL) -m $(LIBTARGET) -d $$(@:$(SLIBSUF)=.def) -l $(SUBDIR)$(SLIBNAME:$(SLIBSUF)=.lib) -D $(SLIBNAME_WITH_MAJOR)'
        SLIB_INSTALL_NAME='$(SLIBNAME_WITH_MAJOR)'
        SLIB_INSTALL_LINKS=
        SLIB_INSTALL_EXTRA_SHLIB='$(SLIBNAME:$(SLIBSUF)=.lib)'
        SLIB_INSTALL_EXTRA_LIB='lib$(SLIBNAME:$(SLIBSUF)=.dll.a) $(SLIBNAME_WITH_MAJOR:$(SLIBSUF)=.def)'
        SHFLAGS='-shared -Wl,--output-def,$$(@:$(SLIBSUF)=.orig.def) -Wl,--out-implib,$(SUBDIR)lib$(SLIBNAME:$(SLIBSUF)=.dll.a) -Wl,--enable-runtime-pseudo-reloc -Wl,--enable-auto-image-base'
        objformat="win32"
        dlltool="${cross_prefix}dlltool"
        ranlib=:
        enable dos_paths
        ;;
    win32|win64)
        disable symver
        if enabled shared; then
            # Link to the import library instead of the normal static library
            # for shared libs.
            LD_LIB='%.lib'
            # Cannot build both shared and static libs with MSVC or icl.
            disable static
        fi
        shlibdir_default="$bindir_default"
        SLIBPREF=""
        SLIBSUF=".dll"
        SLIBNAME_WITH_VERSION='$(SLIBPREF)$(FULLNAME)-$(LIBVERSION)$(SLIBSUF)'
        SLIBNAME_WITH_MAJOR='$(SLIBPREF)$(FULLNAME)-$(LIBMAJOR)$(SLIBSUF)'
        SLIB_CREATE_DEF_CMD='$(SRC_PATH)/compat/windows/makedef $(SUBDIR)lib$(NAME).ver $(OBJS) > $$(@:$(SLIBSUF)=.def)'
        SLIB_INSTALL_NAME='$(SLIBNAME_WITH_MAJOR)'
        SLIB_INSTALL_LINKS=
        SLIB_INSTALL_EXTRA_SHLIB='$(SLIBNAME:$(SLIBSUF)=.lib)'
        SLIB_INSTALL_EXTRA_LIB='$(SLIBNAME_WITH_MAJOR:$(SLIBSUF)=.def)'
        SHFLAGS='-dll -def:$$(@:$(SLIBSUF)=.def) -implib:$(SUBDIR)$(SLIBNAME:$(SLIBSUF)=.lib)'
        objformat="win32"
        ranlib=:
        enable dos_paths
        ;;
    cygwin*)
        target_os=cygwin
        shlibdir_default="$bindir_default"
        SLIBPREF="cyg"
        SLIBSUF=".dll"
        SLIBNAME_WITH_VERSION='$(SLIBPREF)$(FULLNAME)-$(LIBVERSION)$(SLIBSUF)'
        SLIBNAME_WITH_MAJOR='$(SLIBPREF)$(FULLNAME)-$(LIBMAJOR)$(SLIBSUF)'
        SLIB_INSTALL_NAME='$(SLIBNAME_WITH_MAJOR)'
        SLIB_INSTALL_LINKS=
        SLIB_INSTALL_EXTRA_LIB='lib$(FULLNAME).dll.a'
        SHFLAGS='-shared -Wl,--out-implib,$(SUBDIR)lib$(FULLNAME).dll.a'
        objformat="win32"
        enable dos_paths
        ;;
    *-dos|freedos|opendos)
        network_extralibs="-lsocket"
        objformat="coff"
        enable dos_paths
        add_cppflags -U__STRICT_ANSI__
        ;;
    linux)
        enable dv1394
        enable section_data_rel_ro
        ;;
    irix*)
        target_os=irix
        ranlib="echo ignoring ranlib"
        ;;
    os/2*)
        ln_s="cp -f"
        objformat="aout"
        add_cppflags -D_GNU_SOURCE
        add_ldflags -Zomf -Zbin-files -Zargs-wild -Zmap
        SHFLAGS='$(SUBDIR)$(NAME).def -Zdll -Zomf'
        LIBSUF="_s.a"
        SLIBPREF=""
        SLIBSUF=".dll"
        SLIBNAME_WITH_VERSION='$(SLIBPREF)$(NAME)-$(LIBVERSION)$(SLIBSUF)'
        SLIBNAME_WITH_MAJOR='$(SLIBPREF)$(shell echo $(NAME) | cut -c1-6)$(LIBMAJOR)$(SLIBSUF)'
        SLIB_CREATE_DEF_CMD='echo LIBRARY $(SLIBNAME_WITH_MAJOR) INITINSTANCE TERMINSTANCE > $(SUBDIR)$(NAME).def; \
            echo CODE PRELOAD MOVEABLE DISCARDABLE >> $(SUBDIR)$(NAME).def; \
            echo DATA PRELOAD MOVEABLE MULTIPLE NONSHARED >> $(SUBDIR)$(NAME).def; \
            echo EXPORTS >> $(SUBDIR)$(NAME).def; \
            emxexp $(OBJS) >> $(SUBDIR)$(NAME).def'
        SLIB_EXTRA_CMD='emximp -o $(SUBDIR)$(LIBPREF)$(NAME)_dll.a $(SUBDIR)$(NAME).def; \
            emximp -o $(SUBDIR)$(LIBPREF)$(NAME)_dll.lib $(SUBDIR)$(NAME).def;'
        SLIB_INSTALL_EXTRA_LIB='$(LIBPREF)$(NAME)_dll.a $(LIBPREF)$(NAME)_dll.lib'
        enable dos_paths
        ;;
    gnu/kfreebsd)
        add_cppflags -D_BSD_SOURCE
        ;;
    gnu)
        ;;
    qnx)
        add_cppflags -D_QNX_SOURCE
        network_extralibs="-lsocket"
        ;;
    symbian)
        SLIBSUF=".dll"
        enable dos_paths
        add_cflags --include=$sysinclude/gcce/gcce.h -fvisibility=default
        add_cppflags -D__GCCE__ -D__SYMBIAN32__ -DSYMBIAN_OE_POSIX_SIGNALS
        add_ldflags -Wl,--target1-abs,--no-undefined \
                    -Wl,-Ttext,0x80000,-Tdata,0x1000000 -shared \
                    -Wl,--entry=_E32Startup -Wl,-u,_E32Startup
        add_extralibs -l:eexe.lib -l:usrt2_2.lib -l:dfpaeabi.dso \
                      -l:drtaeabi.dso -l:scppnwdl.dso -lsupc++ -lgcc \
                      -l:libc.dso -l:libm.dso -l:euser.dso -l:libcrt0.lib
        ;;
    osf1)
        add_cppflags -D_OSF_SOURCE -D_POSIX_PII -D_REENTRANT
        ;;
    minix)
        ;;
    plan9)
        add_cppflags -D_C99_SNPRINTF_EXTENSION  \
                     -D_REENTRANT_SOURCE        \
                     -D_RESEARCH_SOURCE         \
                     -DFD_SETSIZE=96            \
                     -DHAVE_SOCK_OPTS
        add_compat strtod.o strtod=avpriv_strtod
        network_extralibs='-lbsd'
        exeobjs=compat/plan9/main.o
        cp_f='cp'
        ;;
    none)
        ;;
    *)
        die "Unknown OS '$target_os'."
        ;;
esac

# determine libc flavour

probe_libc(){
    pfx=$1
    pfx_no_=${pfx%_}
    # uclibc defines __GLIBC__, so it needs to be checked before glibc.
    if check_${pfx}cpp_condition features.h "defined __UCLIBC__"; then
        eval ${pfx}libc_type=uclibc
        add_${pfx}cppflags -D_POSIX_C_SOURCE=200112 -D_XOPEN_SOURCE=600
    elif check_${pfx}cpp_condition features.h "defined __GLIBC__"; then
        eval ${pfx}libc_type=glibc
        add_${pfx}cppflags -D_POSIX_C_SOURCE=200112 -D_XOPEN_SOURCE=600
    # MinGW headers can be installed on Cygwin, so check for newlib first.
    elif check_${pfx}cpp_condition newlib.h "defined _NEWLIB_VERSION"; then
        eval ${pfx}libc_type=newlib
        add_${pfx}cppflags -U__STRICT_ANSI__
    # MinGW64 is backwards compatible with MinGW32, so check for it first.
    elif check_${pfx}cpp_condition _mingw.h "defined __MINGW64_VERSION_MAJOR"; then
        eval ${pfx}libc_type=mingw64
        add_${pfx}cppflags -U__STRICT_ANSI__ -D__USE_MINGW_ANSI_STDIO=1
        eval test \$${pfx_no_}cc_type = "gcc" &&
            add_${pfx}cppflags -D__printf__=__gnu_printf__
    elif check_${pfx}cpp_condition _mingw.h "defined __MINGW_VERSION"  ||
         check_${pfx}cpp_condition _mingw.h "defined __MINGW32_VERSION"; then
        eval ${pfx}libc_type=mingw32
        check_${pfx}cpp_condition _mingw.h "__MINGW32_MAJOR_VERSION > 3 || \
            (__MINGW32_MAJOR_VERSION == 3 && __MINGW32_MINOR_VERSION >= 15)" ||
            die "ERROR: MinGW32 runtime version must be >= 3.15."
        add_${pfx}cppflags -U__STRICT_ANSI__ -D__USE_MINGW_ANSI_STDIO=1
        eval test \$${pfx_no_}cc_type = "gcc" &&
            add_${pfx}cppflags -D__printf__=__gnu_printf__
    elif check_${pfx}cpp_condition crtversion.h "defined _VC_CRT_MAJOR_VERSION"; then
        eval ${pfx}libc_type=msvcrt
        if check_${pfx}cpp_condition crtversion.h "_VC_CRT_MAJOR_VERSION < 14"; then
            if [ "$pfx" = host_ ]; then
                add_host_cppflags -Dsnprintf=_snprintf
            else
                add_compat strtod.o strtod=avpriv_strtod
                add_compat msvcrt/snprintf.o snprintf=avpriv_snprintf   \
                                             _snprintf=avpriv_snprintf  \
                                             vsnprintf=avpriv_vsnprintf
            fi
        fi
        # The MSVC 2010 headers (Win 7.0 SDK) set _WIN32_WINNT to
        # 0x601 by default unless something else is set by the user.
        # This can easily lead to us detecting functions only present
        # in such new versions and producing binaries requiring windows 7.0.
        # Therefore explicitly set the default to XP unless the user has
        # set something else on the command line.
        # Don't do this if WINAPI_FAMILY is set and is set to a non-desktop
        # family. For these cases, configure is free to use any functions
        # found in the SDK headers by default. (Alternatively, we could force
        # _WIN32_WINNT to 0x0602 in that case.)
        check_${pfx}cpp_condition stdlib.h "defined(_WIN32_WINNT)" ||
            { check_${pfx}cpp <<EOF && add_${pfx}cppflags -D_WIN32_WINNT=0x0502; }
#ifdef WINAPI_FAMILY
#include <winapifamily.h>
#if !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
#error not desktop
#endif
#endif
EOF
    elif check_${pfx}cpp_condition stddef.h "defined __KLIBC__"; then
        eval ${pfx}libc_type=klibc
    elif check_${pfx}cpp_condition sys/cdefs.h "defined __BIONIC__"; then
        eval ${pfx}libc_type=bionic
    elif check_${pfx}cpp_condition sys/brand.h "defined LABELED_BRAND_NAME"; then
        eval ${pfx}libc_type=solaris
        add_${pfx}cppflags -D__EXTENSIONS__ -D_XOPEN_SOURCE=600
    else
        eval ${pfx}libc_type=default
        add_${pfx}cppflags -D_DEFAULT_SOURCE
    fi
}

probe_libc
test -n "$libc_type" && enable libc_$libc_type
probe_libc host_
test -n "$host_libc_type" && enable host_libc_$host_libc_type

case $libc_type in
    bionic)
        add_compat strtod.o strtod=avpriv_strtod
        ;;
esac

# hacks for compiler/libc/os combinations

if enabled_all tms470 libc_glibc; then
    CPPFLAGS="-I${source_path}/compat/tms470 ${CPPFLAGS}"
    add_cppflags -D__USER_LABEL_PREFIX__=
    add_cppflags -D__builtin_memset=memset
    add_cppflags -D__gnuc_va_list=va_list -D_VA_LIST_DEFINED
    add_cflags   -pds=48    # incompatible redefinition of macro
fi

if enabled_all ccc libc_glibc; then
    add_ldflags -Wl,-z,now  # calls to libots crash without this
fi

check_compile_assert flt_lim "float.h limits.h" "DBL_MAX == (double)DBL_MAX" ||
    add_cppflags '-I\$(SRC_PATH)/compat/float'

esc(){
    echo "$*" | sed 's/%/%25/g;s/:/%3a/g'
}

echo "config:$arch:$subarch:$cpu:$target_os:$(esc $cc_ident):$(esc $LIBAV_CONFIGURATION)" >config.fate

check_cpp_condition stdlib.h "defined(__PIC__) || defined(__pic__) || defined(PIC)" && enable_weak pic

set_default $PATHS_LIST
set_default nm

# we need to build at least one lib type
if ! enabled_any static shared; then
    cat <<EOF
At least one library type must be built.
Specify --enable-static to build the static libraries or --enable-shared to
build the shared libraries as well. To only build the shared libraries specify
--disable-static in addition to --enable-shared.
EOF
    exit 1;
fi

die_license_disabled() {
    enabled $1 || { enabled $2 && die "$2 is $1 and --enable-$1 is not specified."; }
}

die_license_disabled gpl libcdio
die_license_disabled gpl libx264
die_license_disabled gpl libx265
die_license_disabled gpl libxavs
die_license_disabled gpl libxvid
die_license_disabled gpl x11grab

die_license_disabled nonfree libfaac
die_license_disabled nonfree libfdk_aac
die_license_disabled nonfree nvenc
die_license_disabled nonfree openssl

die_license_disabled version3 libopencore_amrnb
die_license_disabled version3 libopencore_amrwb
die_license_disabled version3 libvo_aacenc
die_license_disabled version3 libvo_amrwbenc

enabled version3 && { enabled gpl && enable gplv3 || enable lgplv3; }

disabled optimizations || check_cflags -fomit-frame-pointer

enable_weak_pic() {
    disabled pic && return
    enable pic
    add_cppflags -DPIC
    case "$target_os" in
    mingw*|cygwin*)
        ;;
    *)
        add_cflags -fPIC
        ;;
    esac
    add_asflags  -fPIC
}

enabled pic && enable_weak_pic

check_cc <<EOF || die "Symbol mangling check failed."
int ff_extern;
EOF
sym=$($nm $TMPO | awk '/ff_extern/{ print substr($0, match($0, /[^ \t]*ff_extern/)) }')
extern_prefix=${sym%%ff_extern*}

check_cc <<EOF && enable_weak inline_asm
void foo(void) { __asm__ volatile ("" ::); }
EOF

_restrict=
for restrict_keyword in restrict __restrict__ __restrict; do
    check_cc <<EOF && _restrict=$restrict_keyword && break
void foo(char * $restrict_keyword p);
EOF
done

check_cc <<EOF && enable pragma_deprecated
void foo(void) { _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"") }
EOF

check_cc <<EOF && enable attribute_packed
struct { int x; } __attribute__((packed)) x;
EOF

check_cc <<EOF && enable attribute_may_alias
union { int x; } __attribute__((may_alias)) x;
EOF

check_cc <<EOF || die "endian test failed"
unsigned int endian = 'B' << 24 | 'I' << 16 | 'G' << 8 | 'E';
EOF
od -t x1 $TMPO | grep -q '42 *49 *47 *45' && enable bigendian

check_gas() {
    log "check_gas using '$as' as AS"
    # :vararg is used on aarch64, arm and ppc altivec
    check_as <<EOF || return 1
.macro m n, y:vararg=0
\n: .int \y
.endm
m x
EOF
    # .altmacro is only used in arm asm
    ! enabled arm || check_as <<EOF || return 1
.altmacro
EOF
    enable gnu_as
    return 0
}

if enabled_any arm aarch64 || enabled_all ppc altivec && enabled asm; then
    nogas=:
    enabled_any arm aarch64 && nogas=die
    enabled_all ppc altivec && nogas=warn
    as_noop=-v

    case $as_type in
        arm*) gaspp_as_type=armasm; as_noop=-h ;;
        gcc)  gaspp_as_type=gas ;;
        *)    gaspp_as_type=$as_type ;;
    esac

    [ $target_os = "darwin" ] && gaspp_as_type="apple-$gaspp_as_type"

    check_cmd gas-preprocessor.pl -arch $arch -as-type $gaspp_as_type -- $as $as_noop &&
        gas="gas-preprocessor.pl -arch $arch -as-type $gaspp_as_type -- $as"

    if ! check_gas ; then
        as=${gas:=$as}
        check_gas || \
            $nogas "GNU assembler not found, install/update gas-preprocessor"
    fi

    check_as <<EOF && enable as_func
.func test
.endfunc
EOF
fi

check_inline_asm inline_asm_labels '"1:\n"'

if enabled aarch64; then
    enabled armv8 && check_insn armv8 'prfm   pldl1strm, [x0]'
    # internal assembler in clang 3.3 does not support this instruction
    enabled neon && check_insn neon 'ext   v0.8B, v0.8B, v1.8B, #1'
    enabled vfp  && check_insn vfp  'fmadd d0,    d0,    d1,    d2'

    map 'enabled_any ${v}_external ${v}_inline || disable $v' $ARCH_EXT_LIST_ARM

elif enabled alpha; then

    check_cflags -mieee

elif enabled arm; then

    enabled msvc && check_cpp_condition stddef.h "defined _M_ARMT" && enable thumb
    check_cpp_condition stddef.h "defined __thumb__" && enable_weak thumb
    enabled thumb && check_cflags -mthumb || check_cflags -marm

    if     check_cpp_condition stddef.h "defined __ARM_PCS_VFP"; then
        enable vfp_args
    elif check_cpp_condition stddef.h "defined _M_ARM_FP && _M_ARM_FP >= 30"; then
        enable vfp_args
    elif ! check_cpp_condition stddef.h "defined __ARM_PCS || defined __SOFTFP__" && [ $target_os != darwin ]; then
        case "${cross_prefix:-$cc}" in
            *hardfloat*)         enable vfp_args;   fpabi=vfp ;;
            *) check_ld <<EOF && enable vfp_args && fpabi=vfp || fpabi=soft ;;
__asm__ (".eabi_attribute 28, 1");
int main(void) { return 0; }
EOF
        esac
        warn "Compiler does not indicate floating-point ABI, guessing $fpabi."
    fi

    enabled armv5te && check_insn armv5te 'qadd r0, r0, r0'
    enabled armv6   && check_insn armv6   'sadd16 r0, r0, r0'
    enabled armv6t2 && check_insn armv6t2 'movt r0, #0'
    enabled neon    && check_insn neon    'vadd.i16 q0, q0, q0'
    enabled vfp     && check_insn vfp     'fadds s0, s0, s0'
    enabled vfpv3   && check_insn vfpv3   'vmov.f32 s0, #1.0'

    [ $target_os = linux ] || [ $target_os = android ] ||
        map 'enabled_any ${v}_external ${v}_inline || disable $v' \
            $ARCH_EXT_LIST_ARM

    check_inline_asm asm_mod_q '"add r0, %Q0, %R0" :: "r"((long long)0)'

    check_as <<EOF && enable as_dn_directive
ra .dn d0.i16
.unreq ra
EOF

    # llvm's integrated assembler supports .object_arch from llvm 3.5
    [ "$objformat" = elf ] && check_as <<EOF && enable as_object_arch
.object_arch armv4
EOF

    [ $target_os != win32 ] && enabled_all armv6t2 shared !pic && enable_weak_pic

elif enabled mips; then

    check_inline_asm loongson '"dmult.g $1, $2, $3"'

    # make sure that only an instruction set is enabled
    disable mips64r6 mips32r6 mips64r2 mips32r2 mips64r1 mips32r1

    if enabled mips64; then
        check_inline_asm mips64r6 '"dlsa $0, $0, $0, 1"' ||
            check_inline_asm mips64r2 '"dext $0, $0, 0, 1"' ||
                check_inline_asm mips64r1 '"daddi $0, $0, 0"'
    else
        check_inline_asm mips32r6 '"aui $0, $0, 0"' ||
            check_inline_asm mips32r2 '"ext $0, $0, 0, 1"' ||
                check_inline_asm mips32r1 '"addi $0, $0, 0"'
    fi

elif enabled parisc; then

    if enabled gcc; then
        case $($cc -dumpversion) in
            4.[3-8].*) check_cflags -fno-optimize-sibling-calls ;;
        esac
    fi

elif enabled ppc; then

    enable local_aligned_8 local_aligned_16

    check_inline_asm dcbzl     '"dcbzl 0, %0" :: "r"(0)'
    check_inline_asm ibm_asm   '"add 0, 0, 0"'
    check_inline_asm ppc4xx    '"maclhw r10, r11, r12"'
    check_inline_asm xform_asm '"lwzx %1, %y0" :: "Z"(*(int*)0), "r"(0)'

    # AltiVec flags: The FSF version of GCC differs from the Apple version
    if enabled altivec; then
        check_cflags -maltivec -mabi=altivec &&
        { check_header altivec.h && inc_altivec_h="#include <altivec.h>" ; } ||
        check_cflags -faltivec

        # check if our compiler supports Motorola AltiVec C API
        check_cc <<EOF || disable altivec
$inc_altivec_h
int main(void) {
    vector signed int v1 = (vector signed int) { 0 };
    vector signed int v2 = (vector signed int) { 1 };
    v1 = vec_add(v1, v2);
    return 0;
}
EOF

        enabled altivec || warn "Altivec disabled, possibly missing --cpu flag"
    fi

    if enabled vsx; then
        check_cflags -mvsx &&
        check_builtin vec_vsx_ld "altivec.h" "__builtin_vec_vsx_ld" || disable vsx
    fi

    if enabled power8; then
        check_cpp_condition "altivec.h" "defined(_ARCH_PWR8)" || disable power8
    fi

elif enabled x86; then

    check_builtin rdtsc    intrin.h   "__rdtsc()"
    check_builtin mm_empty mmintrin.h "_mm_empty()"

    enable local_aligned_8 local_aligned_16

    # check whether EBP is available on x86
    # As 'i' is stored on the stack, this program will crash
    # if the base pointer is used to access it because the
    # base pointer is cleared in the inline assembly code.
    check_exec_crash <<EOF && enable ebp_available
volatile int i=0;
__asm__ volatile ("xorl %%ebp, %%ebp" ::: "%ebp");
return i;
EOF

    # check whether EBX is available on x86
    check_inline_asm ebx_available '""::"b"(0)' &&
        check_inline_asm ebx_available '"":::"%ebx"'

    # check whether xmm clobbers are supported
    check_inline_asm xmm_clobbers '"":::"%xmm0"'

    # check whether binutils is new enough to compile SSSE3/MMXEXT
    enabled ssse3  && check_inline_asm ssse3_inline  '"pabsw %xmm0, %xmm0"'
    enabled mmxext && check_inline_asm mmxext_inline '"pmaxub %mm0, %mm1"'

    if ! disabled_any asm mmx yasm; then
        if check_cmd $yasmexe --version; then
            enabled x86_64 && yasm_extra="-m amd64"
            yasm_debug="-g dwarf2"
        elif check_cmd nasm -v; then
            yasmexe=nasm
            yasm_debug="-g -F dwarf"
            enabled x86_64 && test "$objformat" = elf && objformat=elf64
        fi

        YASMFLAGS="-f $objformat $yasm_extra"
        enabled pic               && append YASMFLAGS "-DPIC"
        test -n "$extern_prefix"  && append YASMFLAGS "-DPREFIX"
        case "$objformat" in
            elf*) enabled debug && append YASMFLAGS $yasm_debug ;;
        esac

        check_yasm "movbe ecx, [5]" && enable yasm ||
            die "yasm/nasm not found or too old. Use --disable-yasm for a crippled build."
        check_yasm "vpmacsdd xmm0, xmm1, xmm2, xmm3" || disable xop_external
        check_yasm "vfmadd132ps ymm0, ymm1, ymm2"    || disable fma3_external
        check_yasm "vfmaddps ymm0, ymm1, ymm2, ymm3" || disable fma4_external
        check_yasm "CPU amdnop" || disable cpunop
    fi

    case "$cpu" in
        athlon*|opteron*|k8*|pentium|pentium-mmx|prescott|nocona|atom|geode)
            disable fast_clz
        ;;
    esac

fi

check_code cc arm_neon.h "int16x8_t test = vdupq_n_s16(0)" && enable intrinsics_neon

check_ldflags -Wl,--as-needed

if check_func dlopen; then
    ldl=
elif check_func dlopen -ldl; then
    ldl=-ldl
fi

if ! disabled network; then
    check_func getaddrinfo $network_extralibs
    check_func inet_aton $network_extralibs

    check_type netdb.h "struct addrinfo"
    check_type netinet/in.h "struct group_source_req" -D_BSD_SOURCE
    check_type netinet/in.h "struct ip_mreq_source" -D_BSD_SOURCE
    check_type netinet/in.h "struct ipv6_mreq" -D_DARWIN_C_SOURCE
    check_type poll.h "struct pollfd"
    check_type netinet/sctp.h "struct sctp_event_subscribe"
    check_struct "sys/types.h sys/socket.h" "struct sockaddr" sa_len
    check_type netinet/in.h "struct sockaddr_in6"
    check_type "sys/types.h sys/socket.h" "struct sockaddr_storage"
    check_type "sys/types.h sys/socket.h" socklen_t

    # Prefer arpa/inet.h over winsock2
    if check_header arpa/inet.h ; then
        check_func closesocket
    elif check_header winsock2.h ; then
        check_func_headers winsock2.h closesocket -lws2 &&
            network_extralibs="-lws2" ||
        { check_func_headers winsock2.h closesocket -lws2_32 &&
            network_extralibs="-lws2_32"; } || disable winsock2_h network
        check_func_headers ws2tcpip.h getaddrinfo $network_extralibs

        check_type ws2tcpip.h socklen_t
        check_type ws2tcpip.h "struct addrinfo"
        check_type ws2tcpip.h "struct group_source_req"
        check_type ws2tcpip.h "struct ip_mreq_source"
        check_type ws2tcpip.h "struct ipv6_mreq"
        check_type winsock2.h "struct pollfd"
        check_struct winsock2.h "struct sockaddr" sa_len
        check_type ws2tcpip.h "struct sockaddr_in6"
        check_type ws2tcpip.h "struct sockaddr_storage"
    else
        disable network
    fi
fi

check_builtin atomic_cas_ptr atomic.h "void **ptr; void *oldval, *newval; atomic_cas_ptr(ptr, oldval, newval)"
check_builtin machine_rw_barrier mbarrier.h "__machine_rw_barrier()"
check_builtin MemoryBarrier windows.h "MemoryBarrier()"
check_builtin sync_val_compare_and_swap "" "int *ptr; int oldval, newval; __sync_val_compare_and_swap(ptr, oldval, newval)"

case "$custom_allocator" in
    jemalloc)
        # jemalloc by default does not use a prefix
        require libjemalloc jemalloc/jemalloc.h malloc -ljemalloc
    ;;
    tcmalloc)
        require_pkg_config libtcmalloc gperftools/tcmalloc.h tc_malloc
        malloc_prefix=tc_
    ;;
esac

check_func_headers malloc.h _aligned_malloc     && enable aligned_malloc
check_func  ${malloc_prefix}memalign            && enable memalign
check_func  ${malloc_prefix}posix_memalign      && enable posix_memalign

check_cpp_condition unistd.h "defined(_POSIX_MONOTONIC_CLOCK)" &&
    check_func_headers time.h clock_gettime || { check_func_headers time.h clock_gettime -lrt && add_extralibs -lrt && LIBRT="-lrt"; }

check_func  fcntl
check_func  fork
check_func  gethrtime
check_func  getopt
check_func  getrusage
check_func  gettimeofday
check_func  gmtime_r
check_func  isatty
check_func  localtime_r
check_func  mach_absolute_time
check_func  mkstemp
check_func  mmap
check_func  mprotect
# Solaris has nanosleep in -lrt, OpenSolaris no longer needs that
check_func_headers time.h nanosleep || { check_func_headers time.h nanosleep -lrt && add_extralibs -lrt; }
check_func  sched_getaffinity
check_func  setrlimit
check_func  strerror_r
check_func  sysconf
check_func  sysctl
check_func  usleep

check_func_headers io.h setmode
check_func_headers stdlib.h getenv

check_func_headers windows.h CoTaskMemFree -lole32
check_func_headers windows.h GetProcessAffinityMask
check_func_headers windows.h GetProcessTimes
check_func_headers windows.h GetSystemTimeAsFileTime
check_func_headers windows.h LoadLibrary
check_func_headers windows.h MapViewOfFile
check_func_headers windows.h SetConsoleTextAttribute
check_func_headers windows.h Sleep
check_func_headers windows.h VirtualAlloc
check_struct windows.h "CONDITION_VARIABLE" Ptr

check_header direct.h
check_header dlfcn.h
check_header d3d11.h
check_header dxva.h
check_header dxva2api.h
check_header io.h
check_header mach/mach_time.h
check_header malloc.h
check_header poll.h
check_header sys/mman.h
check_header sys/param.h
check_header sys/resource.h
check_header sys/select.h
check_header sys/time.h
check_header sys/un.h
check_header unistd.h
check_header valgrind/valgrind.h
check_header vdpau/vdpau.h
check_header vdpau/vdpau_x11.h
check_header VideoDecodeAcceleration/VDADecoder.h
check_header windows.h
check_header X11/extensions/XvMClib.h

check_lib2 "windows.h shellapi.h" CommandLineToArgvW -lshell32
check_lib2 "windows.h wincrypt.h" CryptGenRandom -ladvapi32
check_lib2 "windows.h psapi.h" GetProcessMemoryInfo -lpsapi

check_struct "sys/time.h sys/resource.h" "struct rusage" ru_maxrss

check_type "windows.h dxva.h" "DXVA_PicParams_HEVC" -DWINAPI_FAMILY=WINAPI_FAMILY_DESKTOP_APP -D_CRT_BUILD_DESKTOP_APP=0
check_type "windows.h d3d11.h" "ID3D11VideoDecoder"
check_type "d3d9.h dxva2api.h" DXVA2_ConfigPictureDecode -D_WIN32_WINNT=0x0602

if ! disabled w32threads && ! enabled pthreads; then
    check_func_headers "windows.h process.h" _beginthreadex &&
        enable w32threads || disable w32threads
fi

# check for some common methods of building with pthread support
# do this before the optional library checks as some of them require pthreads
if ! disabled pthreads && ! enabled w32threads; then
    enable pthreads
    if check_func pthread_join -pthread; then
        add_cflags -pthread
        add_extralibs -pthread
    elif check_func pthread_join -pthreads; then
        add_cflags -pthreads
        add_extralibs -pthreads
    elif check_func pthread_join -lpthreadGC2; then
        add_extralibs -lpthreadGC2
    elif check_lib pthread.h pthread_join -lpthread; then
        :
    elif ! check_func pthread_join; then
        disable pthreads
    fi
fi

disabled  zlib || check_lib   zlib.h      zlibVersion -lz   || disable  zlib
disabled bzlib || check_lib2 bzlib.h BZ2_bzlibVersion -lbz2 || disable bzlib

check_lib math.h sin -lm && LIBM="-lm"
enabled vaapi && require vaapi va/va.h vaInitialize -lva

atan2f_args=2
ldexpf_args=2
powf_args=2

for func in $MATH_FUNCS; do
    eval check_mathfunc $func \${${func}_args:-1}
done

# these are off by default, so fail if requested and not available
enabled avisynth          && { check_lib2 "avisynth/avisynth_c.h windows.h" LoadLibrary ||
                               check_lib2 "avxsynth/avxsynth_c.h dlfcn.h" dlopen -ldl   ||
                               die "ERROR: LoadLibrary/dlopen not found, or avisynth header not found"; }
enabled frei0r            && { check_header frei0r.h || die "ERROR: frei0r.h header not found"; }
enabled gnutls            && require_pkg_config gnutls gnutls/gnutls.h gnutls_global_init
enabled libbs2b           && require_pkg_config libbs2b bs2b.h bs2b_open
enabled libdcadec         && require libdcadec libdcadec/dca_context.h dcadec_context_create -ldcadec
enabled libfaac           && require2 libfaac "stdint.h faac.h" faacEncGetVersion -lfaac
enabled libfdk_aac        && require_pkg_config fdk-aac "fdk-aac/aacenc_lib.h" aacEncOpen
enabled libfontconfig     && require_pkg_config fontconfig "fontconfig/fontconfig.h" FcInit
enabled libfreetype       && require_pkg_config freetype2 "ft2build.h FT_FREETYPE_H" FT_Init_FreeType
enabled libgsm            && { for gsm_hdr in "gsm.h" "gsm/gsm.h"; do
                                   check_lib "${gsm_hdr}" gsm_create -lgsm && break;
                               done || die "ERROR: libgsm not found"; }
enabled libilbc           && require libilbc ilbc.h WebRtcIlbcfix_InitDecode -lilbc
enabled libkvazaar        && require_pkg_config "kvazaar >= 0.8.1" kvazaar.h kvz_api_get
enabled libmfx            && require_pkg_config libmfx "mfx/mfxvideo.h" MFXInit
enabled libmp3lame        && require "libmp3lame >= 3.98.3" lame/lame.h lame_set_VBR_quality -lmp3lame
enabled libopencore_amrnb && require libopencore_amrnb opencore-amrnb/interf_dec.h Decoder_Interface_init -lopencore-amrnb
enabled libopencore_amrwb && require libopencore_amrwb opencore-amrwb/dec_if.h D_IF_init -lopencore-amrwb
enabled libopencv         && require_pkg_config opencv opencv/cv.h cvCreateImageHeader
enabled libopenh264       && require_pkg_config openh264 wels/codec_api.h WelsGetCodecVersion
enabled libopenjpeg       && { { check_header openjpeg.h && check_lib2 openjpeg.h opj_version -lopenjpeg -DOPJ_STATIC; } ||
                               { require_pkg_config libopenjpeg1 openjpeg.h opj_version -DOPJ_STATIC; } }
enabled libopus           && require_pkg_config opus opus_multistream.h opus_multistream_decoder_create
enabled libpulse          && require_pkg_config libpulse-simple pulse/simple.h pa_simple_new
enabled librtmp           && require_pkg_config librtmp librtmp/rtmp.h RTMP_Socket
enabled libschroedinger   && require_pkg_config schroedinger-1.0 schroedinger/schro.h schro_init
enabled libsnappy         && require snappy snappy-c.h snappy_compress -lsnappy
enabled libspeex          && require_pkg_config speex speex/speex.h speex_decoder_init -lspeex
enabled libtheora         && require libtheora theora/theoraenc.h th_info_init -ltheoraenc -ltheoradec -logg
enabled libtwolame        && require libtwolame twolame.h twolame_init -ltwolame
enabled libvo_aacenc      && require libvo_aacenc vo-aacenc/voAAC.h voGetAACEncAPI -lvo-aacenc
enabled libvo_amrwbenc    && require libvo_amrwbenc vo-amrwbenc/enc_if.h E_IF_init -lvo-amrwbenc
enabled libvorbis         && require libvorbis vorbis/vorbisenc.h vorbis_info_init -lvorbisenc -lvorbis -logg
enabled libvpx            && require_pkg_config "vpx >= 1.3.0" vpx/vpx_codec.h vpx_codec_version && {
    enabled libvpx_vp8_decoder && {
        check_pkg_config vpx "vpx/vpx_decoder.h vpx/vp8dx.h" vpx_codec_vp8_dx ||
            disable libvpx_vp8_decoder;
    }
    enabled libvpx_vp8_encoder && {
        check_pkg_config vpx "vpx/vpx_encoder.h vpx/vp8cx.h" vpx_codec_vp8_cx ||
            disable libvpx_vp8_encoder;
    }
    enabled libvpx_vp9_decoder && {
        check_pkg_config vpx "vpx/vpx_decoder.h vpx/vp8dx.h" vpx_codec_vp9_dx ||
            disable libvpx_vp9_decoder;
    }
    enabled libvpx_vp9_encoder && {
        check_pkg_config vpx "vpx/vpx_encoder.h vpx/vp8cx.h" vpx_codec_vp9_cx ||
            disable libvpx_vp9_encoder;
    }
    if disabled_all libvpx_vp8_decoder libvpx_vp9_decoder libvpx_vp8_encoder libvpx_vp9_encoder; then
        die "libvpx enabled but no supported decoders found"
    fi
}
enabled libwavpack        && require libwavpack wavpack/wavpack.h WavpackOpenFileOutput  -lwavpack
enabled libwebp           && require_pkg_config libwebp webp/encode.h WebPGetEncoderVersion
enabled libx264           && require_pkg_config x264 "stdint.h x264.h" x264_encoder_encode &&
                             { check_cpp_condition x264.h "X264_BUILD >= 118" ||
                               die "ERROR: libx264 version must be >= 0.118."; } &&
                             { check_cpp_condition x264.h "X264_MPEG2" &&
                               enable libx262; }
enabled libx265           && require_pkg_config x265 x265.h x265_api_get &&
                             { check_cpp_condition x265.h "X265_BUILD >= 57" ||
                               die "ERROR: libx265 version must be >= 57."; }
enabled libxavs           && require libxavs xavs.h xavs_encoder_encode -lxavs
enabled libxvid           && require libxvid xvid.h xvid_global -lxvidcore
enabled mmal              && { check_lib interface/mmal/mmal.h mmal_port_connect -lmmal_core -lmmal_util -lmmal_vc_client -lbcm_host ||
                                { ! enabled cross_compile && {
                                    add_cflags -isystem/opt/vc/include/ -isystem/opt/vc/include/interface/vmcs_host/linux -isystem/opt/vc/include/interface/vcos/pthreads -fgnu89-inline ;
                                    add_extralibs -L/opt/vc/lib/ -lmmal_core -lmmal_util -lmmal_vc_client -lbcm_host ;
                                    check_lib interface/mmal/mmal.h mmal_port_connect ; }
                                check_lib interface/mmal/mmal.h mmal_port_connect ; } ||
                               die "ERROR: mmal not found"; }
enabled openssl           && { check_pkg_config openssl openssl/ssl.h SSL_library_init ||
                               check_lib openssl/ssl.h SSL_library_init -lssl -lcrypto ||
                               check_lib openssl/ssl.h SSL_library_init -lssl32 -leay32 ||
                               check_lib openssl/ssl.h SSL_library_init -lssl -lcrypto -lws2_32 -lgdi32 ||
                               die "ERROR: openssl not found"; }

if enabled gnutls; then
    { check_lib2 gmp.h mpz_export -lgmp && enable gmp; } ||
    { check_lib gcrypt.h gcry_mpi_new -lgcrypt && enable gcrypt; }
fi

# libdc1394 check
if enabled libdc1394; then
    { require_pkg_config libdc1394-2 dc1394/dc1394.h dc1394_new &&
        enable libdc1394_2; } ||
    { check_lib libdc1394/dc1394_control.h dc1394_create_handle -ldc1394_control -lraw1394 &&
        enable libdc1394_1; } ||
    die "ERROR: No version of libdc1394 found "
fi

if enabled nvenc; then
    check_header cuda.h || die "ERROR: cuda.h not found.";
    check_header nvEncodeAPI.h || die "ERROR: nvEncodeAPI.h not found.";
    check_cpp_condition nvEncodeAPI.h "NVENCAPI_MAJOR_VERSION >= 5" ||
        die "ERROR: NVENC API version 4 or older is not supported";
fi

if check_pkg_config sdl SDL_events.h SDL_PollEvent; then
    check_cpp_condition SDL.h "(SDL_MAJOR_VERSION<<16 | SDL_MINOR_VERSION<<8 | SDL_PATCHLEVEL) >= 0x010201" $sdl_cflags &&
    check_cpp_condition SDL.h "(SDL_MAJOR_VERSION<<16 | SDL_MINOR_VERSION<<8 | SDL_PATCHLEVEL) < 0x010300" $sdl_cflags &&
    enable sdl
fi

pod2man --help     > /dev/null 2>&1 && enable pod2man   || disable pod2man
texi2html -version > /dev/null 2>&1 && enable texi2html || disable texi2html

check_header linux/fb.h
check_header linux/videodev2.h
check_struct linux/videodev2.h "struct v4l2_frmivalenum" discrete

check_header AVFoundation/AVFoundation.h &&
    check_objcflags -fobjc-arc &&
    add_extralibs -framework Foundation -framework AVFoundation -framework CoreVideo -framework CoreMedia ||
    disable AVFoundation_AVFoundation_h

check_header sys/videoio.h

check_func_headers "windows.h vfw.h" capCreateCaptureWindow "$vfwcap_indev_extralibs"
# check that WM_CAP_DRIVER_CONNECT is defined to the proper value
# w32api 3.12 had it defined wrong
check_cpp_condition vfw.h "WM_CAP_DRIVER_CONNECT > WM_USER" && enable vfwcap_defines

# check for ioctl_meteor.h, ioctl_bt848.h and alternatives
{ check_header dev/bktr/ioctl_meteor.h &&
  check_header dev/bktr/ioctl_bt848.h; } ||
{ check_header machine/ioctl_meteor.h &&
  check_header machine/ioctl_bt848.h; } ||
{ check_header dev/video/meteor/ioctl_meteor.h &&
  check_header dev/video/bktr/ioctl_bt848.h; } ||
check_header dev/ic/bt8xx.h

check_header sndio.h
check_header sys/soundcard.h
check_header soundcard.h

enabled_any alsa_indev alsa_outdev &&
    check_lib2 alsa/asoundlib.h snd_pcm_htimestamp -lasound

enabled jack_indev && check_lib2 jack/jack.h jack_client_open -ljack &&
    check_func jack_port_get_latency_range -ljack

enabled_any sndio_indev sndio_outdev && check_lib2 sndio.h sio_open -lsndio

if enabled libcdio; then
    check_lib2 "cdio/cdda.h cdio/paranoia.h" cdio_cddap_open -lcdio_paranoia -lcdio_cdda -lcdio ||
    check_lib2 "cdio/paranoia/cdda.h cdio/paranoia/paranoia.h" cdio_cddap_open -lcdio_paranoia -lcdio_cdda -lcdio ||
    die "ERROR: No usable libcdio/cdparanoia found"
fi

check_lib X11/Xlib.h XOpenDisplay -lX11 && enable xlib

if enabled libxcb || enabled x11grab && ! disabled libxcb; then
    check_pkg_config xcb-shape xcb/shape.h xcb_shape_rectangles || {
        enabled libxcb && die "ERROR: libxcb not found";
    } && disable x11grab && enable libxcb

    disabled libxcb_shm ||
        check_pkg_config xcb-shm xcb/shm.h xcb_shm_attach || {
            enabled libxcb_shm && die "ERROR: libxcb_shm not found";
        } && check_header sys/shm.h && enable libxcb_shm

    disabled libxcb_xfixes ||
        check_pkg_config xcb-xfixes xcb/xfixes.h xcb_xfixes_get_cursor_image || {
            enabled libxcb_xfixes && die "ERROR: libxcb_xfixes not found";
        } && enable libxcb_xfixes

    add_cflags "$xcb_event_cflags $xcb_shm_cflags $xcb_xfixes_cflags"
    add_extralibs "$xcb_event_libs $xcb_shm_libs $xcb_xfixes_libs"
fi

if enabled x11grab; then
    enabled xlib || die "ERROR: Xlib not found"
    require Xext X11/extensions/XShm.h XShmCreateImage -lXext
    require Xfixes X11/extensions/Xfixes.h XFixesGetCursorImage -lXfixes
fi

enabled vaapi && enabled xlib &&
    check_lib2 "va/va.h va/va_x11.h" vaGetDisplay -lva -lva-x11 &&
    enable vaapi_x11

enabled vdpau &&
    check_cpp_condition vdpau/vdpau.h "defined VDP_DECODER_PROFILE_MPEG4_PART2_ASP" ||
    disable vdpau

enabled vdpau && enabled xlib &&
    check_func_headers "vdpau/vdpau.h vdpau/vdpau_x11.h" vdp_device_create_x11 -lvdpau &&
    prepend avconv_libs $($ldflags_filter "-lvdpau") &&
    enable vdpau_x11

enabled debug && add_cflags -g"$debuglevel" && add_asflags -g"$debuglevel"

# add some useful compiler flags if supported
check_cflags -Wdeclaration-after-statement
check_cflags -Wall
check_cflags -Wdisabled-optimization
check_cflags -Wpointer-arith
check_cflags -Wredundant-decls
check_cflags -Wwrite-strings
check_cflags -Wtype-limits
check_cflags -Wundef
check_cflags -Wmissing-prototypes
check_cflags -Wstrict-prototypes
enabled extra_warnings && check_cflags -Winline
enabled extra_warnings && check_cflags -Wcast-qual

check_disable_warning(){
    warning_flag=-W${1#-Wno-}
    test_cflags $warning_flag && add_cflags $1
}

check_disable_warning -Wno-parentheses
check_disable_warning -Wno-switch
check_disable_warning -Wno-format-zero-length
check_disable_warning -Wno-pointer-sign

# add some linker flags
check_ldflags -Wl,--warn-common
check_ldflags -Wl,-rpath-link=libswscale:libavfilter:libavdevice:libavformat:libavcodec:libavutil:libavresample
enabled rpath && add_ldexeflags -Wl,-rpath,$libdir
test_ldflags -Wl,-Bsymbolic && append SHFLAGS -Wl,-Bsymbolic

# add some strip flags
# -wN '..@*' is more selective than -x, but not available everywhere.
check_stripflags -wN \'..@*\' || check_stripflags -x || strip='true'

enabled neon_clobber_test &&
    check_ldflags -Wl,--wrap,avcodec_open2              \
                  -Wl,--wrap,avcodec_decode_audio4      \
                  -Wl,--wrap,avcodec_decode_video2      \
                  -Wl,--wrap,avcodec_decode_subtitle2   \
                  -Wl,--wrap,avcodec_encode_audio2      \
                  -Wl,--wrap,avcodec_encode_video2      \
                  -Wl,--wrap,avcodec_encode_subtitle    \
                  -Wl,--wrap,avresample_convert ||
    disable neon_clobber_test

enabled xmm_clobber_test &&
    check_ldflags -Wl,--wrap,avcodec_open2              \
                  -Wl,--wrap,avcodec_decode_audio4      \
                  -Wl,--wrap,avcodec_decode_video2      \
                  -Wl,--wrap,avcodec_decode_subtitle2   \
                  -Wl,--wrap,avcodec_encode_audio2      \
                  -Wl,--wrap,avcodec_encode_video2      \
                  -Wl,--wrap,avcodec_encode_subtitle    \
                  -Wl,--wrap,avresample_convert         \
                  -Wl,--wrap,sws_scale ||
    disable xmm_clobber_test

echo "X { local: *; };" > $TMPV
if test_ldflags -Wl,--version-script,$TMPV; then
    append SHFLAGS '-Wl,--version-script,\$(SUBDIR)lib\$(NAME).ver'
elif test_ldflags -Wl,-M,$TMPV; then
    append SHFLAGS '-Wl,-M,\$(SUBDIR)lib\$(NAME).ver-sol2'
fi

check_cc <<EOF && enable symver_asm_label
void ff_foo(void) __asm__ ("av_foo@VERSION");
void ff_foo(void) { ${inline_asm+__asm__($quotes);} }
EOF
    check_cc <<EOF && enable symver_gnu_asm
__asm__(".symver ff_foo,av_foo@VERSION");
void ff_foo(void) {}
EOF

if [ -z "$optflags" ]; then
    if enabled small; then
        optflags=$cflags_size
    elif enabled optimizations; then
        optflags=$cflags_speed
    else
        optflags=$cflags_noopt
    fi
fi

check_optflags(){
    check_cflags "$@"
    enabled lto && check_ldflags "$@"
}


if enabled lto; then
    test "$cc_type" != "$ld_type" && die "LTO requires same compiler and linker"
    check_cflags  -flto
    check_ldflags -flto $cpuflags
fi

check_optflags $optflags
check_optflags -fno-math-errno
check_optflags -fno-signed-zeros

if enabled icc; then
    # Just warnings, no remarks
    check_cflags -w1
    # -wd: Disable following warnings
    # 144, 167, 556: -Wno-pointer-sign
    # 1292: attribute "foo" ignored
    # 1419: external declaration in primary source file
    # 10006: ignoring unknown option -fno-signed-zeros
    # 10148: ignoring unknown option -Wno-parentheses
    # 10156: ignoring option '-W'; no argument required
    check_cflags -wd144,167,556,1292,1419,10006,10148,10156
    # 11030: Warning unknown option --as-needed
    # 10156: ignoring option '-export'; no argument required
    check_ldflags -wd10156,11030
    # icc 11.0 and 11.1 work with ebp_available, but don't pass the test
    enable ebp_available
    if enabled x86_32; then
        icc_version=$($cc -dumpversion)
        test ${icc_version%%.*} -ge 11 &&
            check_cflags -falign-stack=maintain-16-byte ||
            disable aligned_stack
    fi
elif enabled ccc; then
    # disable some annoying warnings
    add_cflags -msg_disable bitnotint
    add_cflags -msg_disable mixfuncvoid
    add_cflags -msg_disable nonstandcast
    add_cflags -msg_disable unsupieee
elif enabled gcc; then
    check_optflags -fno-tree-vectorize
    check_cflags -Werror=implicit-function-declaration
    check_cflags -Werror=missing-prototypes
    check_cflags -Werror=return-type
    check_cflags -Werror=declaration-after-statement
    check_cflags -Werror=vla
    check_cflags -Werror=format-security
    check_cflags -fdiagnostics-color=auto
    enabled extra_warnings || check_disable_warning -Wno-maybe-uninitialized
elif enabled llvm_gcc; then
    check_cflags -mllvm -stack-alignment=16
elif enabled clang; then
    check_cflags -mllvm -stack-alignment=16
    check_cflags -Qunused-arguments
    check_cflags -Werror=implicit-function-declaration
    check_cflags -Werror=missing-prototypes
    check_cflags -Werror=return-type
elif enabled cparser; then
    add_cflags -Wno-missing-variable-declarations
    add_cflags -Wno-empty-statement
elif enabled armcc; then
    add_cflags -W${armcc_opt},--diag_suppress=4343 # hardfp compat
    add_cflags -W${armcc_opt},--diag_suppress=3036 # using . as system include dir
    # 2523: use of inline assembly is deprecated
    add_cflags -W${armcc_opt},--diag_suppress=2523
    add_cflags -W${armcc_opt},--diag_suppress=1207
    add_cflags -W${armcc_opt},--diag_suppress=1293 # assignment in condition
    add_cflags -W${armcc_opt},--diag_suppress=3343 # hardfp compat
    add_cflags -W${armcc_opt},--diag_suppress=167  # pointer sign
    add_cflags -W${armcc_opt},--diag_suppress=513  # pointer sign
elif enabled tms470; then
    add_cflags -pds=824 -pds=837
    disable inline_asm
elif enabled pathscale; then
    add_cflags -fstrict-overflow -OPT:wrap_around_unsafe_opt=OFF
elif enabled_any msvc icl; then
    enabled x86_32 && disable aligned_stack
    enabled_all x86_32 debug && add_cflags -Oy-
    enabled debug && add_ldflags -debug
    enable pragma_deprecated
    if enabled icl; then
        # -Qansi-alias is basically -fstrict-aliasing, but does not work
        # (correctly) on icl 13.x.
        check_cpp_condition "windows.h" "__ICL < 1300 || __ICL >= 1400" &&
            add_cflags -Qansi-alias
        # icl will pass the inline asm tests but inline asm is currently
        # not supported (build will fail)
        disable inline_asm
    fi
    # msvcrt10 x64 incorrectly enables log2, only msvcrt12 (MSVC 2013) onwards actually has log2.
    check_cpp_condition crtversion.h "_VC_CRT_MAJOR_VERSION >= 12" || disable log2
    # The CRT headers contain __declspec(restrict) in a few places, but if redefining
    # restrict, this might break. MSVC 2010 and 2012 fail with __declspec(__restrict)
    # (as it ends up if the restrict redefine is done before including stdlib.h), while
    # MSVC 2013 and newer can handle it fine.
    # If this declspec fails, force including stdlib.h before the restrict redefinition
    # happens in config.h.
    if [ $_restrict != restrict ]; then
        check_cc <<EOF || add_cflags -FIstdlib.h
__declspec($_restrict) void* foo(int);
EOF
    fi
    check_func strtoll || add_cflags -Dstrtoll=_strtoi64
fi

for pfx in "" host_; do
    varname=${pfx%_}cc_type
    eval "type=\$$varname"
    if [ $type = "msvc" ]; then
        check_${pfx}cc <<EOF || add_${pfx}cflags -Dinline=__inline
static inline int foo(int a) { return a; }
EOF
    fi
done

case $as_type in
    clang)
        add_asflags -Qunused-arguments
    ;;
esac

case $ld_type in
    clang)
        check_ldflags -Qunused-arguments
    ;;
esac

case $target_os in
    osf1)
        enabled ccc && add_ldflags '-Wl,-expect_unresolved,*'
    ;;
    plan9)
        add_cppflags -Dmain=plan9_main
    ;;
esac

enabled asm || { arch=c; disable $ARCH_LIST $ARCH_EXT_LIST; }

check_deps $CONFIG_LIST       \
           $CONFIG_EXTRA      \
           $HAVE_LIST         \
           $ALL_COMPONENTS    \

enabled_all dxva2 CoTaskMemFree &&
    prepend avconv_libs $($ldflags_filter "-lole32") &&
    enable dxva2_lib

! enabled_any memalign posix_memalign aligned_malloc &&
    enabled simd_align_16 && enable memalign_hack

map 'enabled $v && intrinsics=${v#intrinsics_}' $INTRINSICS_LIST

for thread in $THREADS_LIST; do
    if enabled $thread; then
        test -n "$thread_type" &&
            die "ERROR: Only one thread type must be selected." ||
            thread_type="$thread"
    fi
done

enabled zlib && add_cppflags -DZLIB_CONST

# conditional library dependencies, in linking order
enabled movie_filter    && prepend avfilter_deps "avformat avcodec"
enabled resample_filter && prepend avfilter_deps "avresample"
enabled scale_filter    && prepend avfilter_deps "swscale"

enabled opus_decoder    && prepend avcodec_deps "avresample"

expand_deps(){
    lib_deps=${1}_deps
    eval "deps=\$$lib_deps"
    append $lib_deps $(map 'eval echo \$${v}_deps' $deps)
    unique $lib_deps
}

map 'expand_deps $v' $LIBRARY_LIST

echo "install prefix            $prefix"
echo "source path               $source_path"
echo "C compiler                $cc"
echo "C library                 $libc_type"
if test "$host_cc" != "$cc"; then
    echo "host C compiler           $host_cc"
    echo "host C library            $host_libc_type"
fi
echo "ARCH                      $arch ($cpu)"
if test "$build_suffix" != ""; then
    echo "build suffix              $build_suffix"
fi
if test "$extra_version" != ""; then
    echo "version string suffix     $extra_version"
fi
echo "big-endian                ${bigendian-no}"
echo "runtime cpu detection     ${runtime_cpudetect-no}"
if enabled x86; then
    echo "${yasmexe}                      ${yasm-no}"
    echo "MMX enabled               ${mmx-no}"
    echo "MMXEXT enabled            ${mmxext-no}"
    echo "3DNow! enabled            ${amd3dnow-no}"
    echo "3DNow! extended enabled   ${amd3dnowext-no}"
    echo "SSE enabled               ${sse-no}"
    echo "SSSE3 enabled             ${ssse3-no}"
    echo "AVX enabled               ${avx-no}"
    echo "XOP enabled               ${xop-no}"
    echo "FMA3 enabled              ${fma3-no}"
    echo "FMA4 enabled              ${fma4-no}"
    echo "i686 features enabled     ${i686-no}"
    echo "CMOV is fast              ${fast_cmov-no}"
    echo "EBX available             ${ebx_available-no}"
    echo "EBP available             ${ebp_available-no}"
fi
if enabled aarch64; then
    echo "NEON enabled              ${neon-no}"
    echo "VFP enabled               ${vfp-no}"
fi
if enabled arm; then
    echo "ARMv5TE enabled           ${armv5te-no}"
    echo "ARMv6 enabled             ${armv6-no}"
    echo "ARMv6T2 enabled           ${armv6t2-no}"
    echo "VFP enabled               ${vfp-no}"
    echo "NEON enabled              ${neon-no}"
fi
if enabled ppc; then
    echo "AltiVec enabled           ${altivec-no}"
    echo "VSX enabled               ${vsx-no}"
    echo "POWER8 enabled            ${power8-no}"
    echo "PPC 4xx optimizations     ${ppc4xx-no}"
    echo "dcbzl available           ${dcbzl-no}"
fi
echo "debug symbols             ${debug-no}"
echo "optimize for size         ${small-no}"
echo "optimizations             ${optimizations-no}"
echo "static                    ${static-no}"
echo "shared                    ${shared-no}"
echo "new filter support        ${avfilter-no}"
echo "network support           ${network-no}"
echo "threading support         ${thread_type-no}"
echo "safe bitstream reader     ${safe_bitstream_reader-no}"
echo "SDL support               ${sdl-no}"
test -n "$random_seed" &&
    echo "random seed               ${random_seed}"
echo

echo "External libraries:"
print_enabled '' $EXTERNAL_LIBRARY_LIST | print_3_columns
echo

for type in decoder encoder hwaccel parser demuxer muxer protocol filter bsf indev outdev; do
    echo "Enabled ${type}s:"
    eval list=\$$(toupper $type)_LIST
    print_enabled '_*' $list | print_3_columns
    echo
done

license="LGPL version 2.1 or later"
if enabled nonfree; then
    license="nonfree and unredistributable"
elif enabled gplv3; then
    license="GPL version 3 or later"
elif enabled lgplv3; then
    license="LGPL version 3 or later"
elif enabled gpl; then
    license="GPL version 2 or later"
fi

echo "License: $license"

echo "Creating config.mak and config.h..."

test -e Makefile || echo "include $source_path/Makefile" > Makefile

config_files="$TMPH config.mak"

cat > config.mak <<EOF
# Automatically generated by configure - do not modify!
LIBAV_CONFIGURATION=$LIBAV_CONFIGURATION
prefix=$prefix
LIBDIR=\$(DESTDIR)$libdir
SHLIBDIR=\$(DESTDIR)$shlibdir
INCDIR=\$(DESTDIR)$incdir
BINDIR=\$(DESTDIR)$bindir
DATADIR=\$(DESTDIR)$datadir
DOCDIR=\$(DESTDIR)$docdir
MANDIR=\$(DESTDIR)$mandir
SRC_PATH=$source_path
CC_IDENT=$cc_ident
ARCH=$arch
INTRINSICS=$intrinsics
CC=$cc
OBJCC=$cc
AS=$as
OBJCC=$objcc
LD=$ld
DEPCC=$dep_cc
DEPCCFLAGS=$DEPCCFLAGS \$(CPPFLAGS)
DEPAS=$as
DEPASFLAGS=$DEPASFLAGS \$(CPPFLAGS)
YASM=$yasmexe
DEPYASM=$yasmexe
AR=$ar
ARFLAGS=$arflags
AR_O=$ar_o
RANLIB=$ranlib
STRIP=$strip
LN_S=$ln_s
CPPFLAGS=$CPPFLAGS
CFLAGS=$CFLAGS
OBJCFLAGS=$OBJCFLAGS
ASFLAGS=$ASFLAGS
AS_C=$AS_C
AS_O=$AS_O
OBJCC_C=$OBJCC_C
OBJCC_E=$OBJCC_E
OBJCC_O=$OBJCC_O
CC_C=$CC_C
CC_E=$CC_E
CC_O=$CC_O
LD_O=$LD_O
LD_LIB=$LD_LIB
LD_PATH=$LD_PATH
DLLTOOL=$dlltool
LDFLAGS=$LDFLAGS
LDEXEFLAGS=$LDEXEFLAGS
SHFLAGS=$(echo $($ldflags_filter $SHFLAGS))
STRIPFLAGS=$STRIPFLAGS
YASMFLAGS=$YASMFLAGS
BUILDSUF=$build_suffix
FULLNAME=$FULLNAME
LIBPREF=$LIBPREF
LIBSUF=$LIBSUF
LIBNAME=$LIBNAME
SLIBPREF=$SLIBPREF
SLIBSUF=$SLIBSUF
EXESUF=$EXESUF
EXTRA_VERSION=$extra_version
CCDEP=$CCDEP
CCDEP_FLAGS=$CCDEP_FLAGS
ASDEP=$ASDEP
ASDEP_FLAGS=$ASDEP_FLAGS
CC_DEPFLAGS=$CC_DEPFLAGS
AS_DEPFLAGS=$AS_DEPFLAGS
HOSTCC=$host_cc
HOSTLD=$host_ld
HOSTCFLAGS=$host_cflags
HOSTCPPFLAGS=$host_cppflags
HOSTEXESUF=$HOSTEXESUF
HOSTLDFLAGS=$host_ldflags
HOSTLIBS=$host_libs
DEPHOSTCC=$host_cc
DEPHOSTCCFLAGS=$DEPHOSTCCFLAGS \$(HOSTCCFLAGS)
HOSTCCDEP=$HOSTCCDEP
HOSTCCDEP_FLAGS=$HOSTCCDEP_FLAGS
HOSTCC_DEPFLAGS=$HOSTCC_DEPFLAGS
HOSTCC_C=$HOSTCC_C
HOSTCC_O=$HOSTCC_O
HOSTLD_O=$HOSTLD_O
TARGET_EXEC=$target_exec $target_exec_args
TARGET_PATH=$target_path
TARGET_SAMPLES=${target_samples:-\$(SAMPLES)}
CFLAGS-avplay=$sdl_cflags
ZLIB=$($ldflags_filter -lz)
LIB_INSTALL_EXTRA_CMD=$LIB_INSTALL_EXTRA_CMD
EXTRALIBS=$extralibs
COMPAT_OBJS=$compat_objs
EXEOBJS=$exeobjs
INSTALL=install
LIBTARGET=${LIBTARGET}
SLIBNAME=${SLIBNAME}
SLIBNAME_WITH_VERSION=${SLIBNAME_WITH_VERSION}
SLIBNAME_WITH_MAJOR=${SLIBNAME_WITH_MAJOR}
SLIB_CREATE_DEF_CMD=${SLIB_CREATE_DEF_CMD}
SLIB_EXTRA_CMD=${SLIB_EXTRA_CMD}
SLIB_INSTALL_NAME=${SLIB_INSTALL_NAME}
SLIB_INSTALL_LINKS=${SLIB_INSTALL_LINKS}
SLIB_INSTALL_EXTRA_LIB=${SLIB_INSTALL_EXTRA_LIB}
SLIB_INSTALL_EXTRA_SHLIB=${SLIB_INSTALL_EXTRA_SHLIB}
SAMPLES:=${samples:-\$(LIBAV_SAMPLES)}
EOF

get_version(){
    lcname=lib${1}
    name=$(toupper $lcname)
    file=$source_path/$lcname/version.h
    eval $(awk "/#define ${name}_VERSION_M/ { print \$2 \"=\" \$3 }" "$file")
    eval ${name}_VERSION=\$${name}_VERSION_MAJOR.\$${name}_VERSION_MINOR.\$${name}_VERSION_MICRO
    eval echo "${lcname}_VERSION=\$${name}_VERSION" >> config.mak
    eval echo "${lcname}_VERSION_MAJOR=\$${name}_VERSION_MAJOR" >> config.mak
    eval echo "${lcname}_VERSION_MINOR=\$${name}_VERSION_MINOR" >> config.mak
}

map 'get_version $v' $LIBRARY_LIST

map 'eval echo "${v}_FFLIBS=\$${v}_deps" >> config.mak' $LIBRARY_LIST

print_program_libs(){
    eval "program_libs=\$${1}_libs"
    eval echo "LIBS-${1}=${program_libs}" >> config.mak
}

map 'print_program_libs $v' $PROGRAM_LIST

cat > $TMPH <<EOF
/* Automatically generated by configure - do not modify! */
#ifndef LIBAV_CONFIG_H
#define LIBAV_CONFIG_H
#define LIBAV_CONFIGURATION "$(c_escape $LIBAV_CONFIGURATION)"
#define LIBAV_LICENSE "$(c_escape $license)"
#define AVCONV_DATADIR "$(eval c_escape $datadir)"
#define CC_IDENT "$(c_escape ${cc_ident:-Unknown compiler})"
#define restrict $_restrict
#define EXTERN_PREFIX "${extern_prefix}"
#define EXTERN_ASM ${extern_prefix}
#define SLIBSUF "$SLIBSUF"
EOF

test -n "$malloc_prefix" &&
    echo "#define MALLOC_PREFIX $malloc_prefix" >>$TMPH

if enabled yasm; then
    append config_files $TMPASM
    printf '' >$TMPASM
fi

enabled getenv || echo "#define getenv(x) NULL" >> $TMPH

print_config ARCH_   "$config_files" $ARCH_LIST
print_config HAVE_   "$config_files" $HAVE_LIST
print_config CONFIG_ "$config_files" $CONFIG_LIST       \
                                     $CONFIG_EXTRA      \
                                     $ALL_COMPONENTS    \

echo "#endif /* LIBAV_CONFIG_H */" >> $TMPH

# Do not overwrite an unchanged config.h to avoid superfluous rebuilds.
cp_if_changed $TMPH config.h
touch .config

enabled yasm && cp_if_changed $TMPASM config.asm

cat > $TMPH <<EOF
/* Generated by ffconf */
#ifndef AVUTIL_AVCONFIG_H
#define AVUTIL_AVCONFIG_H
EOF

print_config AV_HAVE_ $TMPH $HAVE_LIST_PUB

echo "#endif /* AVUTIL_AVCONFIG_H */" >> $TMPH

cp_if_changed $TMPH libavutil/avconfig.h

test -n "$WARNINGS" && printf "\n$WARNINGS"

# build pkg-config files

lib_version(){
    eval printf "\"lib${1} >= \$LIB$(toupper ${1})_VERSION, \""
}

pkgconfig_generate(){
    name=$1
    shortname=${name#lib}${build_suffix}
    comment=$2
    version=$3
    libs=$4
    requires=$(map 'lib_version $v' $(eval echo \$${name#lib}_deps))
    requires=${requires%, }
    enabled ${name#lib} || return 0
    mkdir -p $name
    cat <<EOF > $name/$name.pc
prefix=$prefix
exec_prefix=\${prefix}
libdir=$libdir
includedir=$incdir

Name: $name
Description: $comment
Version: $version
Requires: $(enabled shared || echo $requires)
Requires.private: $(enabled shared && echo $requires)
Conflicts:
Libs: -L\${libdir} -l${shortname} $(enabled shared || echo $libs)
Libs.private: $(enabled shared && echo $libs)
Cflags: -I\${includedir}
EOF
    cat <<EOF > $name/$name-uninstalled.pc
prefix=
exec_prefix=
libdir=\${pcfiledir}
includedir=${source_path}

Name: $name
Description: $comment
Version: $version
Requires: $requires
Conflicts:
Libs: \${libdir}/${LIBPREF}${shortname}${LIBSUF} $libs
Cflags: -I\${includedir}
EOF
}

pkgconfig_generate libavutil     "Libav utility library"          "$LIBAVUTIL_VERSION"     "$LIBRT $LIBM"
pkgconfig_generate libavcodec    "Libav codec library"            "$LIBAVCODEC_VERSION"    "$extralibs"
pkgconfig_generate libavformat   "Libav container format library" "$LIBAVFORMAT_VERSION"   "$extralibs"
pkgconfig_generate libavdevice   "Libav device handling library"  "$LIBAVDEVICE_VERSION"   "$extralibs"
pkgconfig_generate libavfilter   "Libav video filtering library"  "$LIBAVFILTER_VERSION"   "$extralibs"
pkgconfig_generate libavresample "Libav audio resampling library" "$LIBAVRESAMPLE_VERSION" "$LIBM"
pkgconfig_generate libswscale    "Libav image rescaling library"  "$LIBSWSCALE_VERSION"    "$LIBM"