[compiler-rt] [TSan] Add lock_during_write flag on Apple platforms to avoid deadlock (PR #157928)

[Dan Blackwell via llvm-commits]

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@@ -167,8 +167,19 @@ uptr internal_read(fd_t fd, void *buf, uptr count) {
   return read(fd, buf, count);
 }
 
+}  // namespace __sanitizer
+
+// Weak symbol no-op when TSan is not linked
+SANITIZER_WEAK_ATTRIBUTE void __tsan_set_in_internal_write_call(bool value) {}
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DanBlackwell wrote:

TODO: Just move this definition up to the top of the file rather than exit and re-enter the namespace.

https://github.com/llvm/llvm-project/pull/157928