[clang] [clang] Diagnose dangling issues for the "Container<GSLPointer>" case. (PR #107213)

[Utkarsh Saxena via cfe-commits]

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@@ -990,13 +1009,16 @@ static void checkExprLifetimeImpl(Sema &SemaRef,
         //   int &p = *localUniquePtr;
         //   someContainer.add(std::move(localUniquePtr));
         //   return p;
-        IsLocalGslOwner = isRecordWithAttr<OwnerAttr>(L->getType());
+        IsLocalGslOwner =
+            isRecordWithAttr<OwnerAttr>(L->getType()) &&
+            !isContainerOfPointer(L->getType()->getAsRecordDecl());
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usx95 wrote:

This looks useful to be a extracted to a separate function, `IsGSLOwner`. This could be used to replace the  use below as well.

There are other instances `!isRecordWithAttr<OwnerAttr>` which can be replaced as a no-op as well. It would make it more consistent and easy to follow.

https://github.com/llvm/llvm-project/pull/107213