[Bug c++/33819] [4.2/4.3 Regression] Miscompiled shift of C++ bitfield

[pinskia at gcc dot gnu dot org]

------- Comment #1 from pinskia at gcc dot gnu dot org  2007-12-08 19:59 -------
Yes it is done in the 48bit type:
  D.2022 = this->a;
  D.2023 = D.2022 << 16;
  D.2024 = D.2023 >> 16;
  D.2021 = (long long int) D.2024;

But the good question why does it work at -O0.  We have the same IR for both
-O0 and -O1.  Is it because the middle-end expands shifts incorrectly for
partial types still?


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
           Keywords|                            |wrong-code
   Last reconfirmed|0000-00-00 00:00:00         |2007-12-08 19:59:41
               date|                            |
            Summary|Miscompiled shift of C++    |[4.2/4.3 Regression]
                   |bitfield                    |Miscompiled shift of C++
                   |                            |bitfield
   Target Milestone|---                         |4.2.3


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33819