[Bug c++/56394] pointer arithmetic breaks with __attribute__((packed))

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56394

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |INVALID

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> 2013-02-19 14:15:18 UTC ---
Also reproduces with optimization but with -fno-inline.  The issue must be
with the exact division:

  D.2616_5 = end.0_3 - beg.1_4;
  D.2617_6 = D.2616_5 /[ex] 12;

the difference is 4088 but that does not divide by 12.  Which means your
computed end is not correct (the pointers cannot point to elements of
an array of Xyz).