[clang] [clang]: reflection operator parsing for global namespace and primitive types (PR #164692)

[Nhat Nguyen via cfe-commits]

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@@ -1208,6 +1208,13 @@ Parser::ParseCastExpression(CastParseKind ParseKind, bool isAddressOfOperand,
     AllowSuffix = false;
     Res = ParseUnaryExprOrTypeTraitExpression();
     break;
+  case tok::caretcaret: {
+    if (getLangOpts().Reflection) {
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changkhothuychung wrote:

We can add a diagnostic here in the else case about option flag for reflection not turned on, But you left a comment above about whether we need to have an option flag for reflection, so I guess lets resolve that first. 

https://github.com/llvm/llvm-project/pull/164692