Assertion `argc >= 2' failed. Abandon (core dumped)

Question

I'm traying to calculat the multiplication of tow matrix using OPENCL with C: `

#include <CL/cl.h>
# include <stdio.h>
# include <math.h>
# include <assert.h>
# include <sys/stat.h>

char* lire_fichier_source ( const char *nom_fichier )
{
 // On determine la taille du fichier .
 struct stat st ;
 stat ( nom_fichier , &st );
 // On ouvre et on lit le contenu du fichier .
 FILE* fich = fopen ( nom_fichier , " r " );
  assert ( fich != NULL );
 char* programme = (char*) malloc(st.st_size +1);
 fread ( programme, sizeof(char),st.st_size ,fich );
 fclose ( fich );
 
 // La chaine doit se terminer par ASCII 0.
 programme [ st.st_size ]='\0';
 return programme ;
}
 # define PRECISION 0.01
void initialiser ( float *a , size_t N )
{
 int k = 0;
 for ( int i = 0; i < N ; i++) {
   for ( int j = 0; j < N ; j++) {
     a[ i*N + j ] = 1;
   }
 }
}
void imprimer ( const char *nom , float *a , size_t N )
{
 printf("%s::\n", nom );
  for ( int i = 0; i < N ; i++) {
    for ( int j = 0; j < N ; j++) {
      printf ( " %f ", a [ i*N + j ] );
    }
  printf ("\n ");
  }
}
int main (int argc, char** argv )
{
 printf("j'ai entrée");
 // On lit l’argument du programme , qui indique la taille
 // des matrices a generer et multiplier .
 assert( argc >= 2 );
 size_t N = atoi(argv[1]);
 //size_t N=4;
 
 // On obtient un * device * de type GPU .
 cl_platform_id plateforme ;
 clGetPlatformIDs (1, &plateforme,NULL );
 cl_device_id device ;
 clGetDeviceIDs ( plateforme , CL_DEVICE_TYPE_CPU , 1 , &device , NULL );
 printf("je suis dans 1");
 
 // On cree un contexte et une queue d’execution .
 cl_context contexte = clCreateContext ( NULL , 1 , &device , NULL , NULL , NULL );
 printf("je suis dans 2");
 cl_command_queue queue = clCreateCommandQueueWithProperties( contexte , device , 0 , NULL );
 printf("je suis dans 3");
 char *source = lire_fichier_source ( "produit_matrices.cl" );
 printf("je suis dans4");
 cl_program programme = clCreateProgramWithSource ( contexte , 1 ,( const char**)&source,NULL , NULL );
 free ( source );
 // REMARQUE : Si le code du kernel contient une erreur
 // de compilation , c ’ est clBuildProgram qui retourne
 // un resultat indiquant une erreur . Donc , en general ,
 // il est crucial de verifier le code retourne .
 clBuildProgram ( programme , 0 , NULL , NULL , NULL , NULL );
 cl_kernel kernel=clCreateKernel ( programme , " produit_matrices " , NULL );
 float a[ N*N ],b[ N*N ];
 initialiser ( a , N );
 initialiser ( b , N );
 cl_mem buffer_a=clCreateBuffer(contexte,CL_MEM_READ_ONLY | CL_MEM_COPY_HOST_PTR ,sizeof( float )*N*N , a , NULL );
 cl_mem buffer_b =clCreateBuffer( contexte ,CL_MEM_READ_ONLY | CL_MEM_COPY_HOST_PTR ,sizeof( float )*N*N , b , NULL );
 cl_mem buffer_c = clCreateBuffer( contexte , CL_MEM_WRITE_ONLY ,sizeof( float )*N*N , NULL , NULL );
 // On specifie les arguments du kernel et on lance son execution .
 clSetKernelArg( kernel , 0 , sizeof( cl_mem ) , &buffer_a );
 clSetKernelArg( kernel , 1 , sizeof( cl_mem ) , &buffer_b );
 clSetKernelArg( kernel , 2 , sizeof( cl_mem ) , &buffer_c );
 clSetKernelArg( kernel , 3 , sizeof( int ) , &N );
 size_t nb_taches[]={N,N};
 clEnqueueNDRangeKernel( queue , kernel , 2 , NULL , nb_taches ,NULL , 0 , NULL , NULL );
 // On va chercher le resultat : CL_TRUE = > bloquant !
 float c[N*N];
 clEnqueueReadBuffer( queue , buffer_c , CL_TRUE , 0 ,sizeof( float )*N*N , c , 0 , NULL , NULL );
 for ( int i = 0; i < N ; i ++ ) {
   for ( int j = 0; j < N ; j ++ ) {
     if ( fabsf( c [ i*N+j]-(1.0*N ))>PRECISION ) {
        printf("*** Erreur : resultat incorrect [%d , %d ]: %f\n" ,i , j , c[i*N+j]);
        exit( -1 );
     }
   }
  }
 clReleaseMemObject( buffer_a );
 clReleaseMemObject( buffer_b );
 clReleaseMemObject( buffer_c );
 clReleaseKernel(kernel );
 clReleaseProgram(programme );
 clReleaseCommandQueue(queue );
 clReleaseContext(contexte );
 return 0;
}

this is the kernel of the program:

__kernel void produit_matrices ( __global const float* a ,
__global const float* b ,
__global float* c ,
uint N )
{
int i = get_global_id (0);
int j = get_global_id (1);
float total = 0.0;
for ( int k = 0; k<N ; k++ ) {
total += a [i*N+k]*b[k*N+j];
}
c[i*N+j]=total ;
}

please if anyone have the OpenCL thanks to execute it because it give me always "0"

While running a C program, I'm getting the following error and I can't seem to figure out why. I have tried all google solutions but doesn't work

opencl:produits_matrices.c:49: main: Assertion 'argc >= 2' failed. Abandon (core dumped)

Answer 1

As SidoShiro92 has pointed out in his comment, your executable expects you to input an integer number as argument in the console, for example ./opencl 5. Otherwise the assert will throw a runtime error.