I have pushed an alternative fix to lp:~martinal/dolfin/work,
but I'm not yet comfortable pushing it to trunk. It would be nice
if the buildbot got green again sometime soon...


On 28 November 2012 20:58, Joachim Haga <email address hidden> wrote:

> >> Will the circular references "functionspace <->
> >> testfunction" be a problem for garbage collection?
> >
> > Yes.
>
> I am not familiar with the particulars here, but the circular
> references are only a problem if the objects have custom deleters
> (__del__ methods). Swig likes to generate (empty) __del__ methods, but
> they can be disabled by the should-have-been-default flag
> --noproxydel.
>
> -j.
>
> On 28 November 2012 20:03, Johan Hake <email address hidden> wrote:
> > On 11/28/2012 07:15 PM, Martin Sandve Alnæs wrote:
> >> I fixed this permanently by constructing both test and trial function
> >> simultaneously on demand using Argument(V) and storing them to
> >> V._argument_functions. Will the circular references "functionspace <->
> >> testfunction" be a problem for garbage collection?
> >
> > Yes.
> >
> > I wonder how this can be implemented without some error prone
> > heuristics. A robust, but quite intrusive way, would be to always
> > instantiate a TestFunction together with a TrialFunction whenever one
> > need the latter.
> >
> > Or one could introduce a trial and test space specific counter.
> > Something like:
> >
> > class Argument(.):
> >    _test_and_trial_counters = [dict(test=False, trial=False)]
> >    ...
> >
> > class TestFunction(.):
> >     def __init__(.):
> >         .
> >         counters = Argument._test_and_trial_counters
> >         if counters[-1]["test"]:
> >             counters.append(dict(test=False, trial=False))
> >         counters[-1]["test"] = True
> >         Argument(self, ., count=len(counters)*2)
> >
> > class TrialFunction(.):
> >     def __init__(.):
> >         .
> >         counters = Argument._test_and_trial_counters
> >         if counters[-1]["trial"]:
> >             counters.append(dict(test=False, trial=False))
> >         counters[-1]["trial"] = True
> >         Argument(self, ., count=len(counters)*2-1)
> >
> > Johan
> >
> > --
> > You received this bug notification because you are a member of DOLFIN
> > Team, which is subscribed to DOLFIN.
> > https://bugs.launchpad.net/bugs/1083720
> >
> > Title:
> >   replace() fails if the new function spaces have a different mesh
> >
> > Status in DOLFIN:
> >   Fix Committed
> >
> > Bug description:
> >   I submit this bug report following Marie's suggestions on the related
> >   DOLFIN question
> >   (https://answers.launchpad.net/dolfin/+question/215120)
> >
> >   DOLFIN crashes in the solve() routine after using replace() to replace
> >   the function spaces of a form.
> >
> >   While the solve succeeds if replaced function spaces have:
> >   - a different polynomial degree or
> >   - a different polynomial degree and a different mesh,
> >   it does not work if the new function spaces is based on a new mesh
> only.
> >
> >   This is the error message I get:
> >   ***
> -------------------------------------------------------------------------
> >   *** Error: Unable to define linear variational problem a(u, v) = L(v)
> for all v.
> >   *** Reason: Expecting the solution variable u to be a member of the
> trial space.
> >   *** Where: This error was encountered inside
> LinearVariationalProblem.cpp.
> >   ***
> ------------------------------------------------------------------------
> >
> >   The attached file demonstrates the problem.
> >
> > To manage notifications about this bug go to:
> > https://bugs.launchpad.net/dolfin/+bug/1083720/+subscriptions
>
> --
> You received this bug notification because you are a member of DOLFIN
> Core Team, which is subscribed to DOLFIN.
> https://bugs.launchpad.net/bugs/1083720
>
> Title:
>   replace() fails if the new function spaces have a different mesh
>
> Status in DOLFIN:
>   Fix Committed
>
> Bug description:
>   I submit this bug report following Marie's suggestions on the related
>   DOLFIN question
>   (https://answers.launchpad.net/dolfin/+question/215120)
>
>   DOLFIN crashes in the solve() routine after using replace() to replace
>   the function spaces of a form.
>
>   While the solve succeeds if replaced function spaces have:
>   - a different polynomial degree or
>   - a different polynomial degree and a different mesh,
>   it does not work if the new function spaces is based on a new mesh only.
>
>   This is the error message I get:
>   ***
> -------------------------------------------------------------------------
>   *** Error: Unable to define linear variational problem a(u, v) = L(v)
> for all v.
>   *** Reason: Expecting the solution variable u to be a member of the
> trial space.
>   *** Where: This error was encountered inside
> LinearVariationalProblem.cpp.
>   ***
> ------------------------------------------------------------------------
>
>   The attached file demonstrates the problem.
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/dolfin/+bug/1083720/+subscriptions
>