[clang] [clang] Reject references to vector types in `__builtin_vectorelements` (PR #219767)

[Erich Keane via cfe-commits]

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@@ -4742,6 +4742,12 @@ bool Sema::CheckUnaryExprOrTypeTraitOperand(QualType ExprType,
   if (ExprType->isDependentType())
     return false;
 
+  // A reference to a vector type is not a vector type; check this before the
+  // reference is looked through below.
+  if (ExprKind == UETT_VectorElements)
+    return CheckVectorElementsTraitOperandType(*this, ExprType, OpLoc,
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erichkeane wrote:

Can you fix them here too?  And write tests?  It would be nice to fix all at once, particularly since the 'fix' is so trivial.

https://github.com/llvm/llvm-project/pull/219767