1 files changed, 2 insertions, 1 deletions
diff --git a/signal.c b/signal.c
index 1c8f8c112b..2f7796c127 100644
--- a/signal.c
+++ b/signal.c
@@ -803,7 +803,8 @@ check_stack_overflow(int sig, const uintptr_t addr, const ucontext_t *ctx)
     const greg_t bp = mctx->gregs[REG_EBP];
 #   endif
 # elif defined __APPLE__
-#   if __DARWIN_UNIX03
+#   include <AvailabilityMacros.h>
+#   if defined(MAC_OS_X_VERSION_10_5) && MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
 #     define MCTX_SS_REG(reg) __ss.__##reg
 #   else
 #     define MCTX_SS_REG(reg) ss.reg