[clang] [APINotes] Avoid duplicate attributes when fields instantiate class templates (PR #173386)

[Gábor Horváth via cfe-commits]

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@@ -20161,7 +20161,8 @@ void Sema::ActOnFields(Scope *S, SourceLocation RecLoc, Decl *EnclosingDecl,
       CDecl->setIvarRBraceLoc(RBrac);
     }
   }
-  ProcessAPINotes(Record);
+  if (Record && !isa<ClassTemplateSpecializationDecl>(Record))
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Xazax-hun wrote:

Nit: I think you can use something like `isa_and_nonnull`.

https://github.com/llvm/llvm-project/pull/173386