diff options
Diffstat (limited to 'm4/ac_have_sync_val_compare_and_swap.m4')
| -rw-r--r-- | m4/ac_have_sync_val_compare_and_swap.m4 | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/m4/ac_have_sync_val_compare_and_swap.m4 b/m4/ac_have_sync_val_compare_and_swap.m4 new file mode 100644 index 000000000000..88b027e23a29 --- /dev/null +++ b/m4/ac_have_sync_val_compare_and_swap.m4 @@ -0,0 +1,14 @@ +AC_DEFUN([AX_C___SYNC_VAL_COMPARE_AND_SWAP], [ + AC_MSG_CHECKING(for __sync_val_compare_and_swap) + AC_CACHE_VAL(ac_cv___sync_val_compare_and_swap, [ + AC_TRY_LINK( + [], + [int a; if (__sync_val_compare_and_swap(&a, 0, 1)) return 1; return 0;], + ac_cv___sync_val_compare_and_swap=yes, + ac_cv___sync_val_compare_and_swap=no + )]) + if test "$ac_cv___sync_val_compare_and_swap" = "yes"; then + AC_DEFINE(HAVE___SYNC_VAL_COMPARE_AND_SWAP, 1, [define if your compiler has __sync_val_compare_and_swap]) + fi + AC_MSG_RESULT($ac_cv___sync_val_compare_and_swap) +]) |