[Bug tree-optimization/46491] New: [4.3/4.4/4.5 Regression] ipa-pure-const.c miscompilation

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46491

           Summary: [4.3/4.4/4.5 Regression] ipa-pure-const.c
                    miscompilation
           Product: gcc
           Version: 4.5.2
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: ja...@gcc.gnu.org
        ReportedBy: ja...@gcc.gnu.org


extern void abort (void);

__attribute__((noinline)) int
foo (int *p)
{
  int r;
  asm ("movl $6, (%1)\n\txorl %0, %0" : "=r" (r) : "r" (p) : "memory");
  return r;
}

int
main (void)
{
  int p = 8;
  if ((foo (&p) ? : p) != 6)
    abort ();
  return 0;
}

is miscompiled with -O2 in 4.5 (and with -O2 -fno-ipa-reference in
4.1/4.2/4.3/4.4).