#18905: fix more leaks found in #18897
---------------------------+------------------------
Reporter: dimpase | Owner:
Type: defect | Status: new
Priority: major | Milestone: sage-6.8
Component: memleak | Resolution:
Keywords: | Merged in:
Authors: | Reviewers:
Report Upstream: N/A | Work issues:
Branch: | Commit:
Dependencies: #18897 | Stopgaps:
---------------------------+------------------------
Comment (by SimonKing):
Let me try to recall why the current "weak-referencing coerce maps" are
made as they are, to understand why we have a strong reference chain to
`Int_to_IntegerMod`.
- We have a backtracking algorithm to find coerce maps by transitivity of
"registered" coerce maps. Hence, registered coerce maps need to be stored
in the codomain.
- Since the maps are stored in a container that is stored as an attribute
of the codomain, there is a strong reference chain from the codomain to
the coerce map.
- A strong reference to the codomain should not prevent the domain from
garbage collection. Hence, IN COERCION, we use a weak reference from the
map to the domain, and we cut the reference from the map to its parent.
- A strong reference to the domain should not prevent the codomain from
garbage collection. That's what seems to fail in the current example.
What I do not understand: Why is that more than a strong reference CYCLE
(which would not prevent garbage collection) from the codomain to the map
and back?
--
Ticket URL: <http://trac.sagemath.org/ticket/18905#comment:14>
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 unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at http://groups.google.com/group/sage-trac.
For more options, visit https://groups.google.com/d/optout.
