[Bug tree-optimization/68031] [6 Regression] cc1 crashes when compiling newlib / mktm_r.c

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68031

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Yeah, it hits fold_stmt and follows SSA edges via nonnegative but it is not
supposed to (follow SSA edges).  Reduced testcase:

void _mktm_r (long lcltime,  int *res)
{
  long rem = lcltime % ((60L * 60L) * 24L);
  if (rem < 0)
    return;
  while (rem >= ((60L * 60L) * 24L))
      rem -= ((60L * 60L) * 24L);
  *res = (int) (rem % 60L);
}