__nolibc_version
__nolibc_version(__GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__)
__nolibc_version(__clang_major__, __clang_minor__, __clang_patchlevel__)
__nolibc_gnuc_version >= __nolibc_version(4, 6, 0) || \
__nolibc_clang_version >= __nolibc_version(3, 0, 0)