[clang] [clang] Check`T` and `U` operands of __reference_constructs_from_temporary are complete types (PR #206703)

[Yihan Wang via cfe-commits]

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@@ -12,3 +12,9 @@ void f() {
   __is_trivially_relocatable(S); // expected-error{{incomplete type 'S' used in type trait expression}}
   __is_trivially_relocatable(S[]); // expected-error{{incomplete type 'S' used in type trait expression}}
 }
+
+struct NoConv;
+struct Bad;
+
+constexpr bool a = __reference_constructs_from_temporary(S, NoConv&&); // expected-error{{incomplete type 'Bad' used in type trait expression}}
+
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yronglin wrote:

Fixed. we should pass Bad as the 1st operand. I originally wanted to avoid introducing 'Bad' (since 'S' could achieve the same result), but it looks like the change was only partially implemented.

https://github.com/llvm/llvm-project/pull/206703