[clang] In ExprRequirement building, treat OverloadExpr as dependent (PR #66683)

[Erich Keane via cfe-commits]

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@@ -9063,7 +9063,8 @@ Sema::BuildExprRequirement(
     concepts::ExprRequirement::ReturnTypeRequirement ReturnTypeRequirement) {
   auto Status = concepts::ExprRequirement::SS_Satisfied;
   ConceptSpecializationExpr *SubstitutedConstraintExpr = nullptr;
-  if (E->isInstantiationDependent() || ReturnTypeRequirement.isDependent())
+  if (E->isInstantiationDependent() || E->getType()->isPlaceholderType() ||
+      ReturnTypeRequirement.isDependent())
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erichkeane wrote:

I was concerned about other expression types as well, like `OverloadExpr` or placeholders that got put in elsewise, so I was hoping this was sufficiently generic here.

https://github.com/llvm/llvm-project/pull/66683