[clang] [Clang] Avoid assertion failure for initialized extern aliases (PR #223124)

[via cfe-commits]

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@@ -7191,7 +7180,7 @@ static void checkAliasAttr(Sema &S, NamedDecl &ND) {
     if (VD->hasInit()) {
       if (const auto *Attr = VD->getAttr<AliasAttr>()) {
         assert(VD->isThisDeclarationADefinition() &&
-               !VD->isExternallyVisible() && "Broken AliasAttr handled late!");
+               "Broken AliasAttr handled late!");
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keepyixiao wrote:

Thanks for the suggestion. I agree that the assertion should remain as an invariant. I've updated the patch to diagnose this case earlier.

https://github.com/llvm/llvm-project/pull/223124