Re: [png-mng-implement] (no subject)

[Glenn Randers-P. <gl...@gm...>]

On 7/4/07, Glenn Randers-Pehrson <gl...@gm...> wrote:
> On 7/4/07, Greg Roelofs <ne...@po...> wrote:
> > > I tested some more old 64-bit versions of gcc that are available for Ubuntu.
> >
> > > gcc-3.3.6 segfaults when attempting pngtest.  Adding the __PIC__ definition
> > >   does not change anything.
> > > gcc-3.4.6 produces corrupt pngout.png
> > > gcc-4.0.3 succeeds
> > > gcc-4.1.2 succeeds
> >
> > Please try with -O3.  -O2 is the magic failure mode (lots of asm diffs,
> > avg and paeth broken, nothing specific yet identified).  I haven't tried
> > -O1 or -O0 yet.
>
> With -O3, the results were all the same as above (which were with -O2).
>

I also tried -O1, and wish I had not.

gcc-3.3.6 segfaulted.
gcc-3.4.6 produced a slightly different corrupted pngout.png
gcc-4.0.3 produced the same corrupted pngout.png that we saw before.
gcc-4.1.2 succeeds.

Glenn