Re: problem with gnustep on OpenBSD sparc64 -- the journey goes on

[Sebastian Reitenbach]

On Friday, July 8, 2011 16:23 CEST, David Chisnall <theraven@sucs.org> wrote: 
 
> On 8 Jul 2011, at 15:00, Sebastian Reitenbach wrote:
> 
> >> I'm not sure if it's related, but I was seeing 'conditional jump depends 
> >> on uninitialised value' errors in valgrind while loading defaults.  I 
> >> think it was somewhere in GSXML, but I'm not completely sure - by the time 
> >> I got around to trying to find the cause, they'd stopped happening.  I 
> >> assumed that meant someone had fixed the relevant bug, but it might just 
> >> have meant that my defaults settings had changed in a way that stopped the 
> >> bug from being triggered.
> > 
> > I guess, uninitialized variables, the compiler should warn, when it 
> > encounters it while compiling.
> 
> 
> Not always.  In GCC, it only warns at all in an optimised build, because it 
> only computes a code flow graph during optimisation.  In any case, often the 
> compiler doesn't have enough information to know.  For example:
> 
> int foo;
> bar(&foo);
> 
> Is foo used uninitialized?  Maybe.  If bar starts with *foo = 0, then no.  If 
> bar starts with if (foo) then yes.  If bar is defined in another compilation 
> unit, the compiler can't tell.  

ah, thanks for this plausible explanation.

I just wanted to check out valgrind, but had to find out that it is not 
supporting OpenBSD at all...

cheers,
Sebastian


> 
> David
> 
> -- Send from my Jacquard Loom
>