V2522. MISRA. The 'switch' statement should have 'default' as the last label.

This diagnostic rule is based on the software development guidelines developed by MISRA (Motor Industry Software Reliability Association).

This diagnostic rule is relevant only to C++ programs. A 'switch' statement should have 'default' as the last label.

Adding a 'default' label at the end of every 'switch' statement makes the code clearer and guarantees that any possible case where none of the labels matches the value of the control variable will be handled. Since such situations have to be dealt with somehow, every 'default' label should contain (in addition to 'break' or 'throw') an expression or comment explaining why no actions are carried out.

Example 1:

void example_1(int i)
{
  switch (i)
  {
  case 1:
    DoSmth1();
    break;
  default: // <=
    DoSmth42();
    break;
  case 3:
    DoSmth3();
    break;
  }
}

Fixed code:

void example_1(int i)
{
  switch (i)
  {
  case 1:
    DoSmth1();
    break;
  case 3:
    DoSmth3();
    break;
  default:
    DoSmth42();
    break;
  }
}

Example 2:

enum WEEK
{
  SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY
} weekDay;

void example_2()
{
  int isWorkday;

  switch (weekDay)
  {
  case MONDAY:
  case TUESDAY:
  case WEDNESDAY:
  case THURSDAY:
  case FRIDAY:
    isWorkday = 1;
    break;
  case SATURDAY:
  case SUNDAY:
    isWorkday = 0;
    break;
  default: // <=
    break;
}

Fixed code:

enum WEEK
{
  SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY
} weekDay;

void example_2()
{
  int isWorkday;

  switch (weekDay)
  {
  case MONDAY:
  case TUESDAY:
  case WEDNESDAY:
  case THURSDAY:
  case FRIDAY:
    isWorkday = 1;
    break;
  case SATURDAY:
  case SUNDAY:
    isWorkday = 0;
    break;
  default:
    assert(false);
    break;
}

This diagnostic rule is classified as:

Was this page helpful?

Message submitted.

Your message has been sent. We will email you at

If you do not see the email in your inbox, please check if it is filtered to one of the following folders:

• Promotion
• Updates
• Spam

If you can’t find an answer to your question, fill in the form below and our developers will contact you

By clicking this button you agree to our Privacy Policy statement