Re: PARI_stack_limit

[Bill Allombert <Bill.Allombert@math.u-bordeaux1.fr>]

On Fri, Jun 23, 2006 at 09:58:03AM +0200, Bernard Parisse wrote:
> Hello,
> 
> I have a problem when using flisexpr inside a threaded program 
> (more precisely I'm adding a pari command to xcas that should be able
> to execute any PARI command inside xcas, e.g. pari(Euler)),
> it seems related to the PARI_stack_limit check in src/language/anal.c,
> line 1959. The &ptr (in a thread call) is (much) lower than PARI_stack_limit
> and PARI dies with a Deep recursion error (the same code inside
> the readline non-threaded interface icas works correctly). I guess
> this check is here to avoid user recursive calls that end with
> a SEGFAULT (stack capacity exceeded).
> My current fix was to
>   1/ declare PARI_stack_limit in src/headers/paridecl.h
>   2/ set PARI_stack_limit to 0 in xcas code before calling flisexpr
>   (more precisely in the file src/pari.cc from giac-0.6.0.tar.gz)
> It works but it requires modification in the pari library to build
> xcas. Is there another way to do it?

Sure, just declare
extern void *PARI_stack_limit;
in xcas source files.

Adding PARI_stack_limit in src/headers/paridecl.h do not change the
libpari in any way.

Cheers,
Bill.
P.S.
Expect a better answer later on.