Page History

...

void clear(int array[]) {
  size_t i;
  for (i = 0; i < sizeof(array) / sizeof(array[0]); ++i) {
     array[i] = 0;
   }
}
/* ... */

void dowork(void) {
  int dis[12];

  clear(dis);
  /* ... */
}

The footnote in Section 6.5.3.4 of the C Standard \[[ISO/IEC 9899:1999|AA. C References#ISO/IEC 9899-1999]\] explains:

...

void clear(int array[], size_t size) {
  size_t i;
  for (i = 0; i < size; i++) {
     array[i] = 0;
  }
}

/* ... */
void dowork(void) {
  int dis[12];

  clear(dis, sizeof(dis) / sizeof(dis[0]));
  /* ... */
}

This {{sizeof(array) / sizeof(array\[0\])}} idiom will succeed provided the original definition of {{array}} is visible.

Risk Assessment

Incorrectly using the sizeof operator to determine the size of an array can result in a buffer overflow, allowing the execution of arbitrary code.

...

The LDRA tool suite V 7.6.0 is able to detect violations of this recommendation.

Compass Rose /ROSE can detect violations of the recommendation, but it cannot distinguish between incomplete array declarations and pointer declarations.

...