Re: glib memory allocation problems

[Tim Janik <timj imendio com>]

On Tue, 15 May 2007, Miklos Szeredi wrote:

> > > On Fri, 11 May 2007 13:55:25 +0200 (CEST)

> > seems you managed to crash around the slice debugger doing realloc().
> > more interesting than the backtrace should actually be the
> > program output.
> > if you saw something like:
> >    GSlice: MemChecker: attempt to release block with invalid size...
> > then you actually have something to fix.
> > if not, i suspect you have a bad memory corruption somewhere, e.g.
> > where you're writing into already released memory regoins.
> > that can cause crashes pretty much everywhere.
>
> OK, found the problem: g_thread_init() wasn't called by sshfs, and
> hence the thread private data used by gslice wasn't actually thread
> private.
>
> Now I see that the mandatory use of g_thread_init() is documented, but
> it's very non-obvious without reading the docs.  And there are no
> apparent problems if it's not called.  Sshfs got away with it for a
> long time even though people do stress it pretty heavily.
>
> So the question is, should glib not make some sanity checking for code
> that is not actually thread related (like gslice).

it does do sanity checking, it throws a big bold warning if you call
thread_init and gslice in the wrong order:
  http://blogs.gnome.org/view/timj/2007/01/02/0
  http://bugzilla.gnome.org/show_bug.cgi?id=331853

> Dimitrios, there's a patch attached that should fix the crashes.
>
> Thanks,
> Miklos

---
ciaoTJ