[llvm] [Offload] Properly guard modifications to the RPC device array (PR #126790)

[Jan Patrick Lehr via llvm-commits]

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@@ -128,6 +128,7 @@ void RPCServerTy::ServerThread::run() {
     Lock.unlock();
     while (NumUsers.load(std::memory_order_relaxed) > 0 &&
            Running.load(std::memory_order_relaxed)) {
+      std::lock_guard<decltype(Mutex)> Lock(BufferMutex);
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jplehr wrote:

Ok, but if this only occurs when you actually hit RPC I'm much less concerned and think this is fine for now.

https://github.com/llvm/llvm-project/pull/126790