#include <errno.h>
#include <error.h>
#include <limits.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <sys/resource.h>
#include <unistd.h>

static const size_t M_1GB = (size_t) 1 * (size_t) 1024 * (size_t) 1024 * (size_t) 1024;
static const size_t M_2GB = (size_t) 2 * M_1GB;
static const size_t M_4GB = (size_t) 4 * M_1GB;
static const size_t M_8GB = (size_t) 8 * M_1GB;

int
main(int argc, char **argv)
{
  if (argc > 1 && argv[1][0] == 'l')
    {
      struct rlimit lims = { M_1GB / 4, M_1GB / 4 };
      int err = setrlimit(RLIMIT_DATA, &lims);
      if (err == -1)
        {
          error(1, errno, "setrlimit failed");
        }
    }     

  void *addr1 = malloc(M_8GB);

  if (addr1 == NULL)
    {
      error(1, errno, "[addr1] mmap failed: errno=%u, ", errno);
    }

  void *addr2 = malloc(M_8GB);
 
  if (addr2 == NULL)
    {
      free(addr1);
      error(1, errno, "[addr2] mmap failed");
    }

  free(addr1);
  free(addr2);
  return 0;
}