====== bench.cpp ======

This code was used to reproduce the [[/wiki/doku.php?id=library:computing:xios_impi_troubles|Intel MPI bug initializing XIOS server on MN3]]. It can be easily compiled by doing `mpicc bench.cpp -o bench` and then submitted to the scheduler.

<code>

/* skip C++ Binding for mpich , intel MPI */
#define MPICH_SKIP_MPICXX

/* skip C++ Binding for SGI MPI library */
#define MPI_NO_CPPBIND

/* skip C++ Binding for OpenMPI */
#define OMPI_SKIP_MPICXX

#include <mpi.h>

#include <stdio.h>

int main(int argc, char *argv[]){

	int rank;
        int world_size;
	int recv_msgs = 0;
        
        int bufferout[1];
	void* bufferin;

	int flag;
        int receiving;
	int msg_size;
	int rank_src;

	MPI_Status status;
	MPI_Request request;
        
    	MPI_Init(&argc, &argv);
    	MPI_Comm_size(MPI_COMM_WORLD, &world_size);
    	MPI_Comm_rank(MPI_COMM_WORLD, &rank);
	   
	if (world_size < 2)
    	{
        	printf("Please run with two processes.\n");fflush(stdout);
        	MPI_Finalize();
        	return 0;
    	}
    
	if (rank == 0)
    	{

		while (recv_msgs < world_size-1){

			MPI_Iprobe(MPI_ANY_SOURCE,1,MPI_COMM_WORLD, &flag, &status);

			if (flag == true){
				rank_src = status.MPI_SOURCE;
				MPI_Get_count(&status, MPI_INT, &msg_size);
				bufferin=new int[msg_size];
           			MPI_Irecv(bufferin,msg_size,MPI_INT,rank_src,1,MPI_COMM_WORLD,&request);
           			receiving = true;

				while (receiving){
					
					MPI_Test(&request,&flag,&status);
         				if (flag==true)
         				{
						rank_src = status.MPI_SOURCE;
           					MPI_Get_count(&status,MPI_CHAR,&msg_size);
           					delete [] bufferin;
           					receiving = false;
						recv_msgs++;
						printf("%d/%d Recv OK\n", recv_msgs, world_size-1);
					}
				}
			}	
		}
		
                printf("Complete!:Request:%d\n", request);

    	}
   	else{
		bufferout[0] = (world_size * 10000) + rank;
		MPI_Send(bufferout,sizeof(bufferout),MPI_INT,0,1,MPI_COMM_WORLD) ;
	        printf("SentOK:%d\n", rank);	
	} 

	printf("MPI_Finalize:Before:%d\n", rank);
    	MPI_Finalize();
        printf("MPI_Finalize:After:%d\n", rank);
    	return 0;
}

</code>