add configure check for broken gcc 4.9.0 and possibly other versions
[musl] / arch /
drwxr-xr-x   ..
drwxr-xr-x - arm
drwxr-xr-x - i386
drwxr-xr-x - microblaze
drwxr-xr-x - mips
drwxr-xr-x - powerpc
drwxr-xr-x - sh
drwxr-xr-x - x32
drwxr-xr-x - x86_64