[clang] [Clang][Sema] Ensure that the selected candidate for a member function explicit specialization is more constrained than all others (PR #101721)

[Richard Smith via cfe-commits]

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@@ -10465,7 +10466,7 @@ Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
                                                 Previous))
           NewFD->setInvalidDecl();
       }
-    } else if (isMemberSpecialization && isa<CXXMethodDecl>(NewFD)) {
+    } else if (isMemberSpecialization && !FunctionTemplate) {
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zygoloid wrote:

Same question here: are we still doing the checks for an explicit specialization of a member function template?

https://github.com/llvm/llvm-project/pull/101721