[FlopCpp] memory leaks

[Paul Huang]

Hi, Tim

Thanks for fixing the leak. I spent sometime to look at the kinds of mem
leaks Flopc++ has, and it seems that not all leaks are caused by
MP_domain.hpp. Many can be traced to pointers returned by a method call, and
the caller never deletes these pointers afterward. For instance, in
"mp_model.cpp", call getDefaultModel() returns a pointer to MP_model(0), but
it is never deleted.
-------------------------
MP_model& MP_model::default_model = *new MP_model(0);
MP_model* MP_model::current_model = &MP_model::default_model;
MP_model &MP_model::getDefaultModel() { return default_model;}
MP_model *MP_model::getCurrentModel() { return current_model;}
-----------------------

Similar patterns can be found in other places. In "mp_constant.cpp",
---------------------------
 Constant::Constant(double d) :
    Handle<Constant_base*>(new Constant_double(d)) {}
--------------------------
Constant(d) returns a pointer to Constant_double(d), and it is never deleted
by its caller.

I guess it may require a major overhaul to fix all these leaks as there are
many methods return pointers to some newed classes.

Cheers
Paul






On 5/20/07, Tim Hultberg <Tim.Hultberg at eumetsat.int> wrote:
>
> Hi, Paul
>
> yes this one is just as easy as you say. I have fixed it now in
> stable/1.0.
>
> [if you find more easy ones, let me know :-)]
>
> The remaining leaks (I am aware of) comes from some limitations in the
> current implementation of MP_domain. I have a leak free implementation
> of it in branches/experiment/experiment/New_domain.hpp but I have never
> had the time to integrate it properly.
>
> Cheers, Tim
>
> Tim Hultberg
>
> >>> "Paul Huang" <huangpaul99 at gmail.com> 05/18/07 9:33 PM >>>
> Hi, Tim
>
> I understand you know FlopC++ has quite a few memory leaks.  Some are
> minor
> but some are significant. After checking the source code, I assume,
> based on
> my limited understanding, some leaks are easy to fix. For example, in
> mp_model.cpp, a pointer c is newed and passed to "Solver->loadProblem"
> but
> never released. Here is the code
>
> ---------------------------------------------------
> c =  new double[n];
>   for (int j=0; j<n; j++) {
>     c[j] = 0.0;
>   }
>   for (size_t i=0; i<coefs.size(); i++) {
>     int col = coefs[i].col;
>     double elm = coefs[i].val;
>     c[col] = elm;
>   }
>
>   // Column bounds
>   for (int j=0; j<n; j++) {
>     l[j] = 0.0;
>     u[j] = inf;
>   }
>
>   for (varIt i=Variables.begin(); i!=Variables.end(); i++) {
>     for (int k=0; k<(*i)->size(); k++) {
>       l[(*i)->offset+k] = (*i)->lowerLimit.v[k];
>       u[(*i)->offset+k] = (*i)->upperLimit.v[k];
>     }
>   }
>
>   Solver->loadProblem(n, m, Cst, Rnr, Elm, l, u, c, bl, bu);
> -----------------------------------------------
>
> My question is,  is it just as easy as add "delete [] c" after calling
> "Solver->loadProblem" and then the problem will be fixed, or it is not
> as
> easy as it looks and more complication is involved? If the former is
> true,
> then my second question is, when are you going to fix those easy-to-fix
> leaks? :-)
>
>
> Cheers
> Paul
>
>
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