[clang] [clang] Diagnose when spelled 'abi_tag' on namespace doesn't match applied one. (PR #221039)

[Aaron Ballman via cfe-commits]

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@@ -2961,11 +2961,13 @@ static bool mergeDeclAttribute(Sema &S, NamedDecl *D,
         AA->getDeprecated(), AA->getObsoleted(), AA->getUnavailable(),
         AA->getMessage(), AA->getStrict(), AA->getReplacement(), AMK,
         AA->getPriority(), AA->getEnvironment(), InferredPlatformII);
-  } else if (const auto *VA = dyn_cast<VisibilityAttr>(Attr))
-    NewAttr = S.mergeVisibilityAttr(D, *VA, VA->getVisibility());
-  else if (const auto *VA = dyn_cast<TypeVisibilityAttr>(Attr))
-    NewAttr = S.mergeTypeVisibilityAttr(D, *VA, VA->getVisibility());
-  else if (const auto *ImportA = dyn_cast<DLLImportAttr>(Attr))
+  } else if (const auto *VA = dyn_cast<VisibilityAttr>(Attr)) {
+    if (!isa<NamespaceDecl>(D))
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AaronBallman wrote:

This logic should not live here, it should be part of `mergeVisibilityAttr` if anywhere.

https://github.com/llvm/llvm-project/pull/221039