[clang] [Clang] Implement CWG2918 'Consideration of constraints for address of overloaded function' (PR #127773)

[Younan Zhang via cfe-commits]

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@@ -1773,20 +1773,19 @@ bool Sema::IsAtLeastAsConstrained(NamedDecl *D1,
                                   NamedDecl *D2,
                                   MutableArrayRef<const Expr *> AC2,
                                   bool &Result) {
+#ifndef NDEBUG
   if (const auto *FD1 = dyn_cast<FunctionDecl>(D1)) {
     auto IsExpectedEntity = [](const FunctionDecl *FD) {
       FunctionDecl::TemplatedKind Kind = FD->getTemplatedKind();
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zyn0217 wrote:

We have assumed FD2 to be non-null on line 1786, and besides that this change just gets rid of the if-body that is only intended for that assumption.

https://github.com/llvm/llvm-project/pull/127773