Synopsis

Do not declare variables inside a switch statement before the first case label

Enabled by default

Yes

Severity/Certainty

Medium/Low

Full description

Do not declare variables inside a switch statement before the first case label

Coding standards

Code examples

The following code example fails the check and will give a warning:

#include <stdio.h>

extern void f(int i);

void func(int expr) {
  switch (expr) {
    int i = 4;
    f(i);
  case 0:
    i = 17;
    /* Falls through into default code */
  default:
    printf("%d\n", i);
  }
}

The following code example passes the check and will not give a warning about this issue:

#include <stdio.h>

extern void f(int i);

int func(int expr) {
  /*
   * Move the code outside the switch block; now the statements
   * will get executed.
   */
  int i = 4;
  f(i);

  switch (expr) {
    case 0:
      i = 17;
      /* Falls through into default code */
    default:
      printf("%d\n", i);
  }
  return 0;
}