[clang] [clang] Fix for Assertion `(T->hasSignedIntegerRepresentation() || T->isSignedFixedPointType()) && "Unexpected signed integer or fixed point type"' failed. (PR #195945)

[Yanzuo Liu via cfe-commits]

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@@ -31,7 +31,7 @@ void record_context(int a, ...) {
 // Ensure the correct behavior for promotable type UB checking.
 void promotable(int a, ...) {
   enum Unscoped1 { One = 0x7FFFFFFF };
-  (void)__builtin_va_arg(ap, Unscoped1); // ok
+  (void)__builtin_va_arg(ap, Unscoped1); // expected-warning {{second argument to 'va_arg' is of promotable type}}
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zwuis wrote:

IIUC this is a regression, which should not be introduced.

https://github.com/llvm/llvm-project/pull/195945