#include <malloc.h>
#include <stdio.h>
#include <string.h>

int main() {
    int r1 = _heapchk();
    printf("before any alloc: _heapchk=%d\n", r1);
    fflush(stdout);

    void *p = malloc(1024);
    int r2 = _heapchk();
    printf("after malloc(1024): _heapchk=%d (p=%p)\n", r2, p);
    fflush(stdout);

    /* NO corruption - just test if _heapchk works */
    int r3 = _heapchk();
    printf("no corruption: _heapchk=%d\n", r3);
    fflush(stdout);

    free(p);
    int r4 = _heapchk();
    printf("after free: _heapchk=%d\n", r4);
    fflush(stdout);
    return 0;
}