[gecode-users] Memory management bug in 2.2.0?

[Filip Konvička]

Hi Guido,

> the idea was (and still is) to initially allocate all VarArrays from  
> the space, and only when they are resized (by using add), the array is  
> copied to the heap.  That way, most arrays are still efficiently  
> allocated in the space (e.g. copying an array always allocates it in  
> the space again).
> 
> The invariant I had in mind (and which now actually works only since  
> 3.0.0) is the following: the array has been allocated from the space  
> iff used==n (and we renamed used to n and n to capacity...).
> If you're interested in the correct invariants (or back-porting stuff  
> to 2.2.0), they are documented in gecode/kernel/array.hpp in the  
> current version.

thanks for the explanation. The workaround for 2.2.0 is simple:

struct MySpace : Space {
   BoolVarArray bva;
   MySpace(...) {
     std::vector<BoolVar> bva_;
     ...
     bva_.push_back(v);
     ...
     BoolVarArray tmp(this, bva_.size());
     for(int i=bva_.size()-1; i>=0; --i)
       tmp[i]=bva_[i];
     bva=tmp;
     ...
   }
   ...
};

Cheers,
Filip