Examples of implicit barriers in OpenMP and Cilk Plus

cilk.c

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <cilk/cilk.h>

int A[] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };

int main(void)
{
    int i;

    cilk_for (i = 0; i < 10; i++) {
        A[i] += 42;
        sleep(1);
    } // Implicit barrier

    for (i = 0; i < 10; i++) {
        printf("%d\n", A[i]);
    }

    return 0;
}

omp.c

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <omp.h>

int A[] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };

int main(void)
{
    int i;

    #pragma omp parallel num_threads(8)
    {
        #pragma omp single
        for (i = 0; i < 10; i++) {
            #pragma omp task shared(A) firstprivate(i)
            { A[i] += 42; sleep(1); }
        } // Implicit barrier
    } // Implicit barrier

    for (i = 0; i < 10; i++) {
	    printf("%d\n", A[i]);
    }

    return 0;
}