Intel Cilk Plus -- Example #4 (bug with array segment notation)

exmpl4.cpp

#include <stdio.h>
#include <cstdlib>
#include <cilk/cilk.h>
#include <iostream>

/* ex: set tabstop=8 softtabstop=4 expandtab: */

int main(int argc, char* argv[])
{
#define N 16
#define M 16
    int a[M][N];
    cilk_for(int j = 0; j < N; j++) {
        a[0][j] = j + 1;
    }
    cilk_for(int i = 1; i < M; i++) {
        a[i][:] = a[0][:];
    }
    int chunks = 2;
    int chunk = N/chunks;   // make sure  N % chunks == 0
    cilk_for(int k = 0; k < chunks; k++) {
        int start = k * chunk;
        int end = (k + 1) * chunk;
        for(int i = 1; i < M; i++) {
            // this brings wrong results:
            // a[i][start:end] += a[i - 1][start:end];
            // although, this works properly:
            for(int j = start; j < end; j++) {
                a[i][j] += a[i - 1][j];
            }
        }
    }
    for(int i = 0; i < M; i++) {
        for(int j = 0; j < N; j++) {
            printf("%4d ", a[i][j]);
        }
        std::cout << std::endl;
    }
}