[Bug c++/47011] New: ICE when using attribute optimize

[Bug c++/47011] New: ICE when using attribute optimize

[lcastelli at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47011

           Summary: ICE when using attribute optimize
           Product: gcc
           Version: 4.4.5
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: lcastelli@gmail.com
            Target: x86_64-linux-gnu


When compiling the attached file with:
 g++ -O3 -c gcc-crash.cpp

the following error is emitted:
 gcc-crash.cpp: In member function ‘virtual A B::m()’:
 gcc-crash.cpp:7: internal compiler error: in tree_nrv, at tree-nrv.c:143

This happens with gcc 4.4.5 and the current branch on SVN. It doesn't seem to
happen on gcc 4.5.

[Bug c++/47011] ICE when using attribute optimize

[lcastelli at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47011

--- Comment #1 from Lorenzo Castelli <lcastelli at gmail dot com> 2010-12-19 10:18:34 UTC ---
Created attachment 22819
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=22819
Code to reproduce the error

[Bug c++/47011] ICE when using attribute optimize

[mat at lcs dot mit.edu]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47011

--- Comment #2 from Mat Hostetter <mat at lcs dot mit.edu> 2011-09-20 12:31:56 UTC ---
Created attachment 25327
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25327
bug showing ICE with -O, incorrect code without optimization

[Bug c++/47011] ICE when using attribute optimize

[mat at lcs dot mit.edu]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47011

--- Comment #3 from Mat Hostetter <mat at lcs dot mit.edu> 2011-09-20 12:32:47 UTC ---
I am seeing the same crash with gcc 4.4.[3456], on x86_64. It works on 4.6.1.

I encountered this crash when simply upgrading to the latest boost (1.47.0),
which uses attribute optimize, so this is likely to affect other people.

But the bug is more surprising and subtle than just the crash. It can silently
generate incorrect code, which took me longer to track down.

If you compile my attached code optimized you get the internal compiler error.
If you compile it unoptimized, g++ silently changes the calling convention for
vector::begin from by-value to by-reference -- but only if a completely
unrelated empty function is marked with attribute optimize! 

In the full example this meant g++ miscompiled std::vector::begin to use the
wrong calling convention, which when linked into other objects expecting the
proper calling convention would cause a crash.

[Bug middle-end/47011] ICE when using attribute optimize

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47011

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
   Target Milestone|---                         |4.5.0
             Status|UNCONFIRMED                 |RESOLVED

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Fixed so closing.

[Bug middle-end/47011] ICE when using attribute optimize

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47011

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           See Also|                            |https://gcc.gnu.org/bugzill
                   |                            |a/show_bug.cgi?id=60062

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Mat Hostetter from comment #3)
> In the full example this meant g++ miscompiled std::vector::begin to use the
> wrong calling convention, which when linked into other objects expecting the
> proper calling convention would cause a crash.

That was PR 60062.