diff options
| -rw-r--r-- | configure.ac | 16 | ||||
| -rw-r--r-- | pixman/pixman-matrix.c | 2 |
2 files changed, 17 insertions, 1 deletions
diff --git a/configure.ac b/configure.ac index 8a3b622..5ccc267 100644 --- a/configure.ac +++ b/configure.ac @@ -1044,6 +1044,22 @@ fi AC_MSG_RESULT($support_for_float128) +dnl ===================================== +dnl __builtin_clz + +support_for_builtin_clz=no + +AC_MSG_CHECKING(for __builtin_clz) +AC_LINK_IFELSE([AC_LANG_SOURCE([[ +unsigned int x = 11; int main (void) { return __builtin_clz(x); } +]])], support_for_builtin_clz=yes) + +if test x$support_for_builtin_clz = xyes; then + AC_DEFINE([HAVE_BUILTIN_CLZ], [], [Whether the compiler supports __builtin_clz]) +fi + +AC_MSG_RESULT($support_for_builtin_clz) + dnl ================== dnl libpng diff --git a/pixman/pixman-matrix.c b/pixman/pixman-matrix.c index 89b9682..4032c13 100644 --- a/pixman/pixman-matrix.c +++ b/pixman/pixman-matrix.c @@ -37,7 +37,7 @@ static force_inline int count_leading_zeros (uint32_t x) { -#ifdef __GNUC__ +#ifdef HAVE_BUILTIN_CLZ return __builtin_clz (x); #else int n = 0; |