[Bug tree-optimization/85822] New: [8/9 Regression] Maybe wrong code in VRP since r249150

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85822

            Bug ID: 85822
           Summary: [8/9 Regression] Maybe wrong code in VRP since r249150
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: marxin at gcc dot gnu.org
                CC: rguenth at gcc dot gnu.org, ygribov at gcc dot gnu.org
  Target Milestone: ---

I've saw that in qtscript, isolated test-case looks as follows:

$ cat vrp.c
static const long int TagTypeNumber = 0xffff000000000000ll;

long int x;

void foo(void)
{
  x = TagTypeNumber + 1;
}

int main(int argc, char **argv)
{
  if (argc > 0)
    foo ();

  if ((x & TagTypeNumber) == TagTypeNumber)
  {
    unsigned y = (unsigned)x;
    __builtin_printf ("v: %u\n", y);
    if (y != 1)
      __builtin_abort ();
  }

  return 0;
}

$ gcc -O2 vrp.c && ./a.out 
v: 0
Aborted (core dumped)

$