AC_DEFUN([AX_C___BUILTIN_EXPECT], [ | |
AC_MSG_CHECKING(for __builtin_expect) | |
AC_CACHE_VAL(ac_cv___builtin_expect, [ | |
AC_TRY_COMPILE( | |
[int foo(void) { if (__builtin_expect(0, 0)) return 1; return 0; }], | |
[], | |
ac_cv___builtin_expect=yes, | |
ac_cv___builtin_expect=no | |
)]) | |
if test "$ac_cv___builtin_expect" = "yes"; then | |
AC_DEFINE(HAVE___BUILTIN_EXPECT, 1, [define if your compiler has __builtin_expect]) | |
fi | |
AC_MSG_RESULT($ac_cv___builtin_expect) | |
]) |