#13447: Make libsingular multivariate polynomial rings collectable
----------------------------------------------------------------+-----------
Reporter: nbruin |
Owner:
Type: defect |
Status: needs_work
Priority: major |
Milestone: sage-5.4
Component: memleak |
Resolution:
Keywords: | Work
issues: Understand why sometimes `new_RingWrap` needs an incref and sometimes
not
Report Upstream: None of the above - read trac for reasoning. |
Reviewers: Simon King
Authors: Nils Bruin, Simon King | Merged
in:
Dependencies: #11521 |
Stopgaps:
----------------------------------------------------------------+-----------
Comment (by SimonKing):
Replying to [comment:72 nbruin]:
> Replying to [comment:70 SimonKing]:
> > I think one potential problem with our current use of `currRingHdl` in
combination with `rKill` is that we would ''redefine''
`my_awesome_sage_ring`, hence, we would see the following message on
stderr:
> > {{{
> > // ** redefining my_awesome_sage_ring **
> > }}}
> I suspect the records do get cleared, because otherwise Singular would
leave a dangling pointer around and one would have what is essentially a
singular ring variable with NULL pointer to a ring or a pointer to
unallocated memory .
> If those variables do get properly removed, by the time we have to
redefine the thing there should be no trace of the original and hence it
would not be a redefinition.
I am afraid Singular knows that the mock ring has been defined. OK, that's
relative to #12313. But it happened when I did
{{{
sage: from sage.rings.polynomial.plural import SCA
sage: E = SCA(QQ, ['x', 'y', 'z'], [0, 1], order = 'degrevlex')
sage: import gc
sage: del E
sage: _ = gc.collect()
sage: E = SCA(QQ, ['x', 'y', 'z'], [0, 1], order = 'degrevlex')
}}}
#12313 is needed to make E collectable.
Hans didn't answer, but I found out myself:
`currRingHdl=rFindHdl(currRing,NULL,NULL)`, which could still be NULL. If
it is NULL, then we may create the mock ring.
> Are we the only ones ever setting `currRingHdl` or can one write/call
singular functions that internally will change `currRingHdl`?
No idea.
--
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/13447#comment:73>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/sage-trac?hl=en.
