[clang] [C++] Fix a crash with __thread and dependent types (PR #140542)

[Erich Keane via cfe-commits]

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@@ -14608,6 +14608,10 @@ void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
   std::optional<bool> CacheHasConstInit;
   const Expr *CacheCulprit = nullptr;
   auto checkConstInit = [&]() mutable {
+    const Expr *Init = var->getInit();
+    if (Init->isInstantiationDependent())
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erichkeane wrote:

Oh wait, 14706 seems to protect against that, it has the value-dependent check.  So NVM.

https://github.com/llvm/llvm-project/pull/140542