[clang] [Sema] Fix crash in Sema::FindInstantiatedDecl (PR #96509)

[Alejandro Álvarez Ayllón via cfe-commits]

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@@ -6300,7 +6300,7 @@ NamedDecl *Sema::FindInstantiatedDecl(SourceLocation Loc, NamedDecl *D,
                   getTrivialTemplateArgumentLoc(UnpackedArg, QualType(), Loc));
           }
           QualType T = CheckTemplateIdType(TemplateName(TD), Loc, Args);
-          if (T.isNull())
+          if (T.isNull() || T->containsErrors())
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alejandro-alvarez-sonarsource wrote:

There is no reason besides that it is where I saw the crash. I have moved into `CheckTemplateIdType`. 

https://github.com/llvm/llvm-project/pull/96509