__glibc_has_extension   54 maint/gnulib/lib/cdefs.h # define __glibc_has_extension(ext) __has_extension (ext)
__glibc_has_extension   56 maint/gnulib/lib/cdefs.h # define __glibc_has_extension(ext) 0
__glibc_has_extension  149 maint/gnulib/lib/libc-config.h # undef __glibc_has_extension