Deactivate MALLOC_CHECK_ on x86_64

[Andreas Hartmetz]

On Tuesday 17 November 2009 00:05:29 Andreas Hartmetz wrote:
> On Monday 16 November 2009 11:22:09 Stephan Kulow wrote:
> > Am Freitag 13 November 2009 schrieb Raphael Kubo da Costa:
> > > On Friday 13 November 2009 13:11:57 Alex Fiestas wrote:
> > > > Hi
> > > > Seems that MALLOC_CHECK_ feature of glibc is kind of broken in
> > > > x86_64, giving false positives. In release mode this has no effect to
> > > > the user, just when you're running KDE in development mode,
> > > > MALLOC_CHECK_ will be set at 2, which means that malloc will abort
> > > > the application when one of that false given errors happen.
> > > >
> > > > So I suggest to deactivate MALLOC_CHECK_ on 64 bits systems, at least
> > > > until it gets fixed.
> > > >
> > > > Some applications that usually crash on my system are:
> > > > - digikam (I'm in digikam sprint right now and I've asked gilles and
> > > > he agrees)
> > > > - kdevelop (I'm with apol here and he's concerned about this issue
> > > > too).
> > > >
> > > > Everybody agrees with that?
> > > >
> > > > *http://techbase.kde.org/Development/malloc_check
> > >
> > > Are you sure about it being broken only in x86_64? I'm running x86 and
> > >  always get false positives too. I don't remember mpyne or maelcum
> > >  perceiving it as a 64-bit-only problem either.
> >
> > It's broken in glibc 2.10, not architecture specific. openSUSE runs the
> >  whole system during the beta phase on MALLOC_CHECK_=3 and we had a lot
> > of fun with this ;(
> >
> > But disabling MALLOC_CHECK_ on KDE makes little sense as KDE has almost
> > no way to find out if the system is affected or not - openSUSE's glibc
> > 2.10 is not. Perhaps you can apply openSUSE's patch to your glibc?
> >
> > Greetings, Stephan
> 
> Downloading the package and extracting the relevant patch took me a while,
>  so I've attached the patch here.
> 
Update: the bug report Michael linked to is just as good as a source of the 
actual patch.