[Bug tree-optimization/95246] New: Failure to optimize comparison between differently signed chars

[gabravier at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95246

            Bug ID: 95246
           Summary: Failure to optimize comparison between differently
                    signed chars
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gabravier at gmail dot com
  Target Milestone: ---

bool f(unsigned char a, signed char b)
{
    return a > b;
}

This can be optimized to `return (signed char)a > b;`. This transformation is
done by LLVM, but not by GCC.