[llvm] [Offload] Make olLaunchKernel test thread safe (PR #149497)

[Ross Brunton via llvm-commits]

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@@ -487,16 +487,10 @@ Error olWaitQueue_impl(ol_queue_handle_t Queue) {
   // Host plugin doesn't have a queue set so it's not safe to call synchronize
   // on it, but we have nothing to synchronize in that situation anyway.
   if (Queue->AsyncInfo->Queue) {
-    if (auto Err = Queue->Device->Device->synchronize(Queue->AsyncInfo))
+    if (auto Err = Queue->Device->Device->synchronize(Queue->AsyncInfo, false))
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RossBrunton wrote:

Correct, although as far as I know, liboffload doesn't do that, and that feels reasonable as a thing to mark as undefined.

https://github.com/llvm/llvm-project/pull/149497