[arch-dev-public] [toolchain] gcc 4.5 breakage

Allan McRae allan at archlinux.org
Tue May 4 20:46:06 EDT 2010

On 05/05/10 08:23, Thomas Bächler wrote:
> I noticed problem with gcc 4.5 and the GAP system
> (http://www.gap-system.org) first: It throws a few aliasing warnings,
> and the program breaks. When I used -fno-strict-aliasing, the warnings
> disappeared, but the breakage remained, unless I used -O0. Fixing the
> aliasing problems also fixed the breakage.
> Now I noticed the exact same issue with busybox:
> - Building with -Os throws lots of aliasing warnings, busybox's sed breaks
> - Building with -Os -fno-strict-aliasing builds without warnings, but it
> still breaks.
> - Building with -O0 works, but it isn't optimal.

Interesting...  Does fixing the aliasing fix this one too? I see no 
upstream bug reports that seem related so you should follow it up there. 
  I will pull in a new gcc-4.5 snapshot next week when I do the 
glibc-2.12 toolchain rebuild so hopefully that may contain a fix that I 
am missing...

> This will affect LOTS of other programs and these errors will not show
> up as errors or warnings during the build procedure.

As an aside 15% of the packages in the repos have been updated since gcc 
made it to [core].  From the lack of bug reports, the breakage does not 
appear too widespread

More information about the arch-dev-public mailing list