[clang] [Clang][Sema] Improve support for explicit specializations of constrained member functions & member function templates (PR #88963)

[Qizhi Hu via cfe-commits]

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@@ -275,6 +275,13 @@ Response HandleFunction(Sema &SemaRef, const FunctionDecl *Function,
                                      TemplateArgs->asArray(),
                                      /*Final=*/false);
 
+    if (RelativeToPrimary &&
+        (Function->getTemplateSpecializationKind() ==
+             TSK_ExplicitSpecialization ||
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jcsxky wrote:

Is this condition `Function->getTemplateSpecializationKind() == TSK_ExplicitSpecialization` necessary? I removed it and all testcases passed. Could you please add a testcase to cover it which would fail without this condition?

https://github.com/llvm/llvm-project/pull/88963