[Bug middle-end/121017] New: `__builtin_copysign(0.0, a)` should be optimized to 0.0 for -fno-signed-zeros

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121017

            Bug ID: 121017
           Summary: `__builtin_copysign(0.0, a)` should be optimized to
                    0.0 for -fno-signed-zeros
           Product: gcc
           Version: 16.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---

>From https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121004#c7 :
```
float f(float a)
{
  return __builtin_copysignf(0.0, a);
}
```

This should just be 0.0 with -fno-signed-zeros