[Bug c/127383] [C23 _BitInt] wrong code for complement of unsigned _BitInt(63) converted to unsigned long long

[rguenth at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127383

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2026-09-14
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
  long long unsigned int w = ~(long long unsigned int) s.f;

the promotion behavior of s.f looks guilty.  note long long  f : 63
would not promote to long long;  > int bitfields are a GNU extension,
maybe _BitInt bitfields are now standard.