[clang] [Clang] Require base element type of `__has_unique_object_representations` to be complete (PR #95432)

[Mital Ashok via cfe-commits]

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@@ -2791,6 +2791,12 @@ bool ASTContext::hasUniqueObjectRepresentations(
     return hasUniqueObjectRepresentations(getBaseElementType(Ty),
                                           CheckIfTriviallyCopyable);
 
+  if (Ty->isVoidType())
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MitalAshok wrote:

For the new `!Ty->isIncompleteType()` assertion below. Before `void` would go to the `!isTriviallyCopyable` path, this is just a more explicit way of handling `__has_unique_object_representations(void)`. The assertion could also be `assert(Ty->isVoidType() || !Ty->isIncompleteType())` to follow the spec better?


https://github.com/llvm/llvm-project/pull/95432