Re: Fix for Cygwin/GSlice problem

[Ken Brown]

On 12/8/2009 8:33 PM, Stefan Monnier wrote:
> > +/* Emacs supplies its own malloc, but glib (part of Gtk+) calls
> > +   memalign and on Cygwin, that becomes the Cygwin supplied memalign.
> > +   As malloc is not the Cygwin malloc, the Cygwin memalign always
> > +   returns ENOSYS.  A workaround is to set G_SLICE=always-malloc. */
> > +#define G_SLICE_ALWAYS_MALLOC
>
> Why does Cygwin-Emacs use its own malloc rather than the system malloc?

There was a long thread about this on the Cygwin list in 2007, in which 
Jan Djärv tried to sort this out.  It starts at

  http://cygwin.com/ml/cygwin/2007-02/threads.html#00469

and continues at

  http://cygwin.com/ml/cygwin/2007-02/threads.html#00503

I'm afraid a lot of that discussion is over my head.  All I can say is 
that the Emacs build brings in the Emacs malloc and friends, but when 
glib calls memalign, the Cygwin memalign gets called instead of the one 
supplied by Emacs.  Maybe Jan can explain why it wasn't possible to 
change this or to simply use Cygwin's malloc and friends.  He seemed 
optimistic at the end of thread, but then the discussion stopped.

Ken