[clang] [Clang] Access tls_guard via llvm.threadlocal.address (PR #96633)

[John McCall via cfe-commits]

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@@ -769,9 +777,10 @@ void CodeGenModule::EmitCXXModuleInitFunc(Module *Primary) {
       CharUnits GuardAlign = CharUnits::One();
       Guard->setAlignment(GuardAlign.getAsAlign());
       GuardAddr = ConstantAddress(Guard, Int8Ty, GuardAlign);
+      IsTLS = Guard->isThreadLocal();
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rjmccall wrote:

This is always just `false`.  And I believe that's correct, module initialization is global, not thread-local.

https://github.com/llvm/llvm-project/pull/96633