[clang] [llvm] [LLVM] Add GNU make jobserver support (PR #145131)

[James Y Knight via llvm-commits]

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@@ -156,16 +226,22 @@ Executor *Executor::getDefaultExecutor() {
                        ThreadPoolExecutor::Deleter>
       ManagedExec;
   static std::unique_ptr<ThreadPoolExecutor> Exec(&(*ManagedExec));
-  return Exec.get();
+  TheExec = Exec.get();
 #else
   // ManagedStatic is not desired on other platforms. When `Exec` is destroyed
   // by llvm_shutdown(), worker threads will clean up and invoke TLS
   // destructors. This can lead to race conditions if other threads attempt to
   // access TLS objects that have already been destroyed.
   static ThreadPoolExecutor Exec(strategy);
-  return &Exec;
+  TheExec = &Exec;
 #endif
 }
+
+Executor *Executor::getDefaultExecutor() {
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jyknight wrote:

Why is this function added? Initialization of a function-local "static" variable is already call-once, so this wrapper shouldn't be doing anything.

https://github.com/llvm/llvm-project/pull/145131