[clang] [clang-tools-extra] [clang] Implement CWG2398 provisional TTP matching to class templates (PR #94981)

[Matheus Izvekov via cfe-commits]

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@@ -9219,7 +9222,8 @@ class Sema final : public SemaBase {
   /// \returns true if an error occurred, false otherwise.
   bool CheckTemplateArgumentList(
       TemplateDecl *Template, SourceLocation TemplateLoc,
-      TemplateArgumentListInfo &TemplateArgs, bool PartialTemplateArgs,
+      TemplateArgumentListInfo &TemplateArgs,
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mizvekov wrote:

I am not seeing a worthwhile tradeoff.

Just the function signature is hugely complicated, and would need to be duplicated.
The implementation would be mostly the same, with a small block which would be omitted in one of the implementations.

What did you have in mind?

https://github.com/llvm/llvm-project/pull/94981