c - Segmentation fault 11 thread program -

i'm having error "segmentation fault 11" following code : created thread give in parameters struct.

i think problem in declaration of function *marit.

sorry bad english french.

struct parametres {         double *t; int n; //taille };  void *marit(struct parametres parametres) { int *somme =0; float *moyenne = 0; int i; for(i = 0; < parametres.n; i++) *somme = *somme + parametres.t[i]; printf("somme : %d",somme); *moyenne = (*somme/(parametres.n+0.0)); pthread_exit(moyenne); }`   int main(int argc, char* argv[]) { float temps; clock_t t1, t2; t1 = clock(); struct parametres params; printf("salut √† toi !\n"); printf("donnez la taille du tableau :" ); scanf("%d", &params.n); params.t = malloc( params.n * sizeof(double) ); int = 0; int nombre_aleatoire = 0; for(i=0; i<params.n; i++){ nombre_aleatoire =  (rand() % 1000) + 1; params.t[i]=nombre_aleatoire; } pthread_t arith,quadrat,cubi; if(pthread_create(&arith, null, marit, (void*)&params) != 0) { perror("pthread_create"); exit(1); } double *result=0; pthread_join(arith, (void**)&result); printf("le resultat du thread : %f",result);  return 0; } 

i don't know what's problem.

there couple of problems code.

first, signature of marit. must take sinlge void* parameter.

second, somme , moyenne declared pointers, don't allocate memory them. causing segfault.

third, return value must void pointer. means must have size of pointer , value points must persist past call (returning address of automatic variable inside marit not ok).

fourth, main expects double returned, change type of moyenne.

fixing 3 issues done this:

void *marit(void *param) {     struct parametres *parametres = (struct parametres*)param;     int somme =0;     double moyenne = 0, *ret;     int i;     for(i = 0; < parametres->n; i++)         somme = somme + parametres->t[i];     printf("somme : %d",somme);     moyenne = (somme/(parametres->n+0.0));     ret = malloc(sizeof ret);     *ret = moyenne;     pthread_exit(ret); } 

note that, when main function done processing retrun value should free it. in case, program ends right afterwards, freeing memory not necessary.

you need change printf in main:

printf("le resultat du thread : %f", *result);