Re: Pure space overflow (Cygwin)

[Eli Zaretskii]

> Date: Fri, 19 Oct 2012 22:45:36 -0400
> From: Ken Brown <address@hidden>
> CC: Angelo Graziosi <address@hidden>, address@hidden
> 
> > I bumped the base value by 80000, so it should solve your problem.
> > Perhaps Ken should look into tuning SYSTEM_PURESIZE_EXTRA (on
> > conf_post.h) for Cygwin, since no other system seems to have this
> > problem at this time.
> 
> I could certainly do this, although there's no need at the moment after 
> your increase.  Or are you suggesting that I revert your change and then 
> tune SYSTEM_PURESIZE_EXTRA for Cygwin?

Reverting the change won't tell you enough detail to set the extra
puresize correctly, because you don't know how close to the limit are
Unix and GNU platforms, which is what the BASE_PURESIZE is set for.

What you need is compare the values of pure-bytes-used in "emacs -Q"
between Emacs compiled on Cygwin and on some Unix or GNU system.
(Make sure both builds use the same configuration options and are done
on platforms with the same size of basic data types and of EMACS_INT,
which probably means a 32-bit Unix or GNU system.)  Then subtract
these two values and round up.

Another alternative is to run "temacs -batch -l loadup" under GDB, set
a breakpoint in pure_alloc, and record every allocation that comes
from Cygwin-specific code; summing them up should give you the extra.
But this is much more tedious, as you'd have to examine lots of
allocations.