[clang] Fix assertion failure during conversion function overload resolution. (PR #98671)

[Daniel M. Katz via cfe-commits]

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@@ -1519,7 +1519,8 @@ bool Sema::IsAtLeastAsConstrained(NamedDecl *D1,
     auto IsExpectedEntity = [](const FunctionDecl *FD) {
       FunctionDecl::TemplatedKind Kind = FD->getTemplatedKind();
       return Kind == FunctionDecl::TK_NonTemplate ||
-             Kind == FunctionDecl::TK_FunctionTemplate;
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katzdm wrote:

Actually, there might be some deeper issues; will follow up off-thread.

https://github.com/llvm/llvm-project/pull/98671