[Bug middle-end/127965] [14/15/16/17 Regression] wrong code with __atomic_fetch_or since r13-3760

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127965

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org
           Keywords|                            |wrong-code
     Ever confirmed|0                           |1
           Priority|P3                          |P2
             Status|UNCONFIRMED                 |NEW
            Summary|wrong code with             |[14/15/16/17 Regression]
                   |__atomic_fetch_or           |wrong code with
                   |                            |__atomic_fetch_or since
                   |                            |r13-3760
   Last reconfirmed|                            |2026-10-17
   Target Milestone|---                         |14.5

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Started with r13-3760-g03ed4e57e3d46a61513b3d1ab1720997aec8cf71

Testcase not dependent on the exact char and int precisions:
int
main ()
{
  int x = (unsigned char) (-__SCHAR_MAX__ - 1);
  int v = __atomic_fetch_or (&x, -__INT_MAX__ - 1, __ATOMIC_SEQ_CST);
  if ((signed char) v >= 0)
    __builtin_abort ();
}