Fix bswap16 issue on Debian 6.

Versions of GCC prior to 4.8 didn't provide an implementation
of __builtin_bswap16 on x86_64. Detect those versions and
supply a fallback implementation. A cleaner fix would be
to detect bswap16 independently of bswap32 in configure
and handle them separately.

See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52624

Signed-off-by: Erik de Castro Lopo <erikd@mega-nerd.com>
1 file changed