[clang] [clang-tools-extra] [clang] Improved canonicalization for template specialization types (PR #135119)

[Erich Keane via cfe-commits]

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@@ -3250,8 +3251,7 @@ checkBuiltinTemplateIdType(Sema &SemaRef, BuiltinTemplateDecl *BTD,
 
     TemplateArgument NumArgsArg = Converted[2];
     if (NumArgsArg.isDependent())
-      return Context.getCanonicalTemplateSpecializationType(TemplateName(BTD),
-                                                            Converted);
+      return QualType();
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erichkeane wrote:

Can you explain what is happening here?  Why are we no longer returning a type?

https://github.com/llvm/llvm-project/pull/135119