Re: question on trouble shooting gp pari sessions which suddenly quit running

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

On Wed, Apr 24, 2024 at 08:25:48AM -0700, American Citizen wrote:
> > ellsaturation(E, V, B): let E be an elliptic curve over Q and V be a
> > vector of independent rational points on E of infinite order that
> > generate
> > a subgroup G of E(Q) of finite index. Return a new set W of the same
> > length that generate a subgroup H of E(Q) containing G and such that
> > [E(Q):H] is not divisible by any prime number less than B.
> I turned on capturing the error stream and found a strange error occurring
> 
> ellsaturation: no more variables available.
> 
> And at this point the program goes into run-away, with all output to the
> error stream and rapidly parses all the lines in the script until end of
> file.
> 
> What does this error mean?

There is a bug in ellsaturation:
Polynomial indeterminates are numbered and limited to 2^16.
The function ellQ_saturation is allocating a variable number
and is not freeing after use.

I assume you see this:

E=ellinit([-157^2,0]);P=ellheegner(E);
for(i=1,2^17,ellsaturation(E,[P],10))
  ***   at top-level: ...lheegner(E);for(i=1,2^17,ellsaturation(E,[P],1
  ***                                             ^---------------------
  *** ellsaturation: no more variables available.

I just pushed this commit which should fix this issue:

commit e5978b6091c6a4f5933bbcffa0d091271e26eb7e
Author: Bill Allombert <Bill.Allombert@math.u-bordeaux.fr>
Date:   Wed Apr 24 17:45:29 2024 +0200

    14- ellsaturation was leaking variable numbers

Thanks for reporting this bug!
Bill.