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

[Tom Honermann via cfe-commits]

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@@ -525,13 +519,12 @@ Bug Fixes in This Version
 - Clang now emits an error for friend declarations of lambda members. (#GH26540)
 - Fixed a crash caused by lambda capture handling in delayed default arguments. (#GH176534)
 - Fixed a crash when parsing invalid ``static_assert`` declarations with string-literal messages (#GH187690).
+- Fixed an crash in ``__builtin_va_arg`` when the argument type is an enum without a corresponding signed type (#GH191698).
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tahonermann wrote:

```suggestion
- Fixed a crash in ``__builtin_va_arg`` when the argument type is an enum without a corresponding signed type (#GH191698).
```

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