[Bug tree-optimization/106711] Incorrect format overflow warning with previously checked strings

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106711

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2022-08-22
             Status|UNCONFIRMED                 |NEW

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed. I suspect what is happening is that GCC finds the strlen for each
string seperately and sees its max is 4094 (because add) and does not take into
account the strings are done together.


  _1 = strlen (in1_8(D));
  _2 = strlen (in2_9(D));
  _3 = _1 + _2;
  _4 = _3 + 2;
  if (_4 <= 4096)
    goto <bb 3>; [38.32%]
  else
    goto <bb 4>; [61.68%]

  <bb 3> [local count: 411457864]:
  sprintf (outbuf_10(D), "%s/%s", in1_8(D), in2_9(D));