[PATCH] D60956: [Sema] Fix the lookup for a declaration conflicting with an enumerator (bogus use of LookupResult::getAsSingle)

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman added inline comments.


================
Comment at: lib/Sema/SemaDecl.cpp:16607
+  // Check for other kinds of shadowing not already handled.
+  if (PrevDecl && isa<ValueDecl>(PrevDecl->getUnderlyingDecl()) &&
+      !TheEnumDecl->isScoped())
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riccibruno wrote:
> aaron.ballman wrote:
> > Is the change to `PrevDecl->getUnderlyingDecl()` intended here?
> Yes it is. Previously it was done inside `LookupResult::getAsSingle`. However with this patch `PrevDecl` at this point can be a `UsingShadowDecl` for a given using-declaration. We need to look for the underlying declaration since this is what `CheckShadow` expects.
But when it's not a `UsingShadowDecl`, will the behavior now be incorrect? e.g., if it was a `NamespaceAliasDecl`, won't this check whether you are shadowing the aliased namespace as opposed to the alias name itself? Might be worth some tests.


Repository:
  rC Clang

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D60956/new/

https://reviews.llvm.org/D60956