[PATCH] D122248: [clang][CodeGen]Fix clang crash and add bitfield support in __builtin_dump_struct

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman added a comment.

In D122248#3403143 <https://reviews.llvm.org/D122248#3403143>, @yihanaa wrote:

> 1. Support zero-width bitfield, named bitfield and unnamed bitfield.
> 2. Add a release notes.
>
> The builtin function __builtin_dump_struct behaves for zero-width bitfield and unnamed bitfield as follows
>
>   int printf(const char *fmt, ...);
>   
>   void foo(void) {
>     struct Bar {
>       unsigned c : 1;
>       unsigned : 3;
>       unsigned : 0;
>       unsigned b;
>     };
>   
>     struct Bar a = {
>       .c = 1,
>       .b = 2022,
>     };
>   
>     __builtin_dump_struct(&a, &printf);
>   }
>   
>   int main() {
>     foo();
>     return 0;
>   }
>
> Output:
>
>   struct Bar {
>   unsigned int c : 1
>   unsigned int  : 0
>   unsigned int b : 2022
>   }

Thank you for the release note and additional test coverage. I'm wondering why we handle the zero-width bit-field differently from the anonymous one (e.g., why do we not have `unsigned int : 3` before the `unsigned int : 0`? It seems a bit odd to drop that from the output.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D122248/new/

https://reviews.llvm.org/D122248