[clang] [clang] Fix @tparam warnings for concept template parameters (PR #199800)

[Corentin Jabot via cfe-commits]

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@@ -857,7 +862,8 @@ bool Sema::isTemplateOrSpecialization() {
     return false;
   if (!ThisDeclInfo->IsFilled)
     inspectThisDecl();
-  return ThisDeclInfo->getTemplateKind() != DeclInfo::NotTemplate;
+  return ThisDeclInfo->getTemplateKind() != DeclInfo::NotTemplate ||
+         isa<ConceptDecl>(ThisDeclInfo->CommentDecl);
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cor3ntin wrote:

I think the underlying issue is that `void DeclInfo::fill()` does not handle concepts. can you investigate that?

https://github.com/llvm/llvm-project/pull/199800