[compiler-rt] TSAN: Report when thread is not live and referenced in pthread (PR #156921)

[via llvm-commits]

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@@ -274,6 +274,11 @@ void ThreadRegistry::JoinThread(u32 tid, void *arg) {
     {
       ThreadRegistryLock l(this);
       ThreadContextBase *tctx = threads_[tid];
+
+      if (!tctx) {
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ghostway0 wrote:

I think this is wrong, this shouldn't have been added (also this wouldn't resolve the issue for non-join problems)

https://github.com/llvm/llvm-project/pull/156921