[Bug sanitizer/58443] New: ubsan doesn't properly honor fsanitize= flags

[mpolacek at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58443

            Bug ID: 58443
           Summary: ubsan doesn't properly honor fsanitize= flags
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: sanitizer
          Assignee: unassigned at gcc dot gnu.org
          Reporter: mpolacek at gcc dot gnu.org
                CC: dodji at gcc dot gnu.org, dvyukov at gcc dot gnu.org,
                    jakub at gcc dot gnu.org, kcc at gcc dot gnu.org

$ cat z.c
int
main (void)
{
  int i = 12;
  i <<= 48;
  return 0;
}

$ gcc -w -o z{,.c} -fsanitize=unreachable && ./z
z.c:5:5: runtime error: shift exponent 48 is too large for 32-bit type int

We shouldn't instrument shifts, only __builtin_unreachable's in this case.