compat: add a fallback implementation of C23 stdbit.h

Header contents taken from VLC commit 7a970a33329c9836d169727ddbaf49a33240d587.

Signed-off-by: Anton Khirnov <anton@khirnov.net>

1 files changed, 4 insertions, 0 deletions

diff --git a/configure b/configure
index 99bd3ca7bf..d77a55b653 100755
--- a/configure
+++ b/configure
@@ -7788,6 +7788,10 @@ if disabled stdatomic; then
     fi
 fi
 
+check_builtin stdbit "stdbit.h assert.h" \
+    'static_assert(__STDC_VERSION_STDBIT_H__ >= 202311L, "Compiler lacks stdbit.h")' || \
+    add_cppflags '-I\$(SRC_PATH)/compat/stdbit'
+
 # Check if requested libraries were found.
 for lib in $AUTODETECT_LIBS; do
     requested $lib && ! enabled $lib && die "ERROR: $lib requested but not found";