AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
AC_CHECK_HEADERS_ONCE([sys/time.h])
AC_CHECK_MEMBERS([struct stat.st_birthtimespec.tv_nsec], [],
[AC_CHECK_MEMBERS([struct stat.st_birthtimensec], [],
[AC_CHECK_MEMBERS([struct stat.st_birthtim.tv_nsec], [], [],
AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
AC_CHECK_HEADERS_ONCE([sys/time.h])
AC_CHECK_MEMBERS([struct stat.st_birthtimespec.tv_nsec], [],
[AC_CHECK_MEMBERS([struct stat.st_birthtimensec], [],
[AC_CHECK_MEMBERS([struct stat.st_birthtim.tv_nsec], [], [],