Hi,
I am trying to use MPI derived datatype doutines for sending a struct
which contains dynamically allocated arrays. I tried implementing it
using MPI_Type_struct. It doesn't throws any error but messages being
received (of the declared datatype) aren't correct. Some memory
corruption seems to be going on as the value of 'rank' at receive end
are changed to 0 right after the receive . Below are the snippets of my
struct and implementation of the derived datatype.
I am not sure where things are going wrong. I would highly appreciate
any pointers or suggestions. Is there any better alternative way instead
of MPI_Type_struct considering that  frequent communication of these
structs are needed?

Thanks,
Jitendra

The struct looks like this:
     51 typedef struct
     52 {
     53     int *intvar;                  
     54     double *realvar;             
     55     double *binvar;              
     56     int **gene;                    
     57
     58     double *obj;                   
     59     double *constr;                
     60     double constr_violation;      
     61     double crowd_dist;          
     62     int rank;                      
     63     double *strategyParameter;     
     64 }
     65 individual;

Implementation of the derived datatype:

    483         blockcounts[0] = parentPop[0].numInteger;
    484         blockcounts[1] = parentPop[0].numReal;
    485         blockcounts[2] = parentPop[0].numBinary;
    486         sum = 0;
    487         for(i=0; i<parentPop[0].numBinary; i++)
    488         {
    489             sum = sum + parentPop[0].nbits[i];
    490         }
    491
    492         blockcounts[3] = sum;
    493         blockcounts[4] = parentPop[0].nobj;
    494         blockcounts[5] = parentPop[0].ncon;
    495         blockcounts[6] = 1;
    496         blockcounts[7] = 1;
    497         blockcounts[8] = 1;
    498         blockcounts[9] = parentPop[0].numInteger +
parentPop[0].numReal;

    506         types[0] = MPI_INT;
    507         types[1] = MPI_DOUBLE;
    508         types[2] = MPI_DOUBLE;
    509         types[3] = MPI_INT;
    510         types[4] = MPI_DOUBLE;
    511         types[5] = MPI_DOUBLE;
    512         types[6] = MPI_DOUBLE;
    513         types[7] = MPI_DOUBLE;
    514         types[8] = MPI_INT;
    515         types[9] = MPI_DOUBLE;
    516
    517         MPI_Get_address(&parentPop[0].indiv[0].intvar, &disp[0]);
    518         printf("parentpop.indiv0 %ld disp %ld (%ld)\n",
&parentPop[0].indiv[0], disp, disp[0]);
    519         MPI_Get_address(&parentPop[0].indiv[0].realvar, &disp[1]);
    520         printf("disp 1 %ld\n", disp[1]);
    521         MPI_Get_address(&parentPop[0].indiv[0].binvar, &disp[2]);
    522         printf("disp 2 %ld\n", disp[2]);
    523         MPI_Get_address(&parentPop[0].indiv[0].gene, &disp[3]);
    524         MPI_Get_address(&parentPop[0].indiv[0].obj, &disp[4]);
    525         MPI_Get_address(&parentPop[0].indiv[0].constr, &disp[5]);
    526         MPI_Get_address(&parentPop[0].indiv[0].constr_violation,
&disp[6]);
    527         MPI_Get_address(&parentPop[0].indiv[0].crowd_dist,
&disp[7]);
    528         MPI_Get_address(&parentPop[0].indiv[0].rank, &disp[8]);
    529        
MPI_Get_address(&parentPop[0].indiv[0].strategyParameter, &disp[9]);
    530         base = disp[0];
    531         for(i=0; i<10; i++)
    532         {
    533             disp[i] -= base;
    534         }
    535        
    536         MPI_Type_create_struct(10, blockcounts, disp, types,
&Individual);
    537
    538         /* Check that the datatype has correct extent */
    539         MPI_Type_extent(Individual, &extent);
    540         if(extent != sizeof(individual))
    541         {
    542             MPI_Datatype indold = Individual;
    543             MPI_Type_create_resized(indold, 0,
sizeof(individual), &Individual);
    544             MPI_Type_free(&indold);
    545         }
    546         MPI_Type_commit(&Individual);

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