[compiler-rt] [TSan] Add interceptor for os_unfair_lock_lock_with_flags (PR #153815)

[Julian Lettner via llvm-commits]

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@@ -15,6 +16,18 @@ void *Thread(void *a) {
   return NULL;
 }
 
+#if defined(__MAC_15_0)
+void *ThreadWithFlags(void *a) {
+#  pragma clang diagnostic push
+#  pragma clang diagnostic ignored "-Wunguarded-availability-new"
+  os_unfair_lock_lock_with_flags(&lock, OS_UNFAIR_LOCK_FLAG_ADAPTIVE_SPIN);
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yln wrote:

Nit: This test code here is "normal" code.  I think we should try to use `__builtin_available()` which the proper way to guard calls to new API, i.e., what user code would do.

https://github.com/llvm/llvm-project/pull/153815