Better test for presence of __sync_swap().

15 years ago · 69e53c4cdb
parent 893b9bf958
commit 69e53c4cdb
1 changed files with 4 additions and 1 deletions
--- a/gc_boehm.c
+++ b/gc_boehm.c
@ -58,7 +58,10 @@ struct objc_slot* objc_get_slot(Class cls, SEL selector);
 #include <gc/gc.h>
 #include <gc/gc_typed.h>

-#ifndef __clang__
+#ifndef __has_builtin
+#	define __has_builtin(x) 0
+#endif
+#if __has_builtin(__sync_swap)
 #define __sync_swap __sync_lock_test_and_set
 #endif