Valid, but worthless syntax in switch-case?

Question

Through a little typo, I accidentally found this construct:

int main(void) {
    char foo = \'c\';

    switch(foo)
    {
        printf(\"Cant Touch This\\n\");         


        

Answer 1

Does this serve any purpose at all?

Yes. If instead of a statement, you put a declaration before the first label, this can make perfect sense:

switch (a) {
  int i;
case 0:
  i = f(); g(); h(i);
  break;
case 1:
  i = g(); f(); h(i);
  break;
}

The rules for declarations and statements are shared for blocks in general, so it's the same rule that allows that that also allows statements there.

---

Worth mentioning as well is also that if the first statement is a loop construct, case labels may appear in the loop body:

switch (i) {
  for (;;) {
    f();
  case 1:
    g();
  case 2:
    if (h()) break;
  }
}

Please don't write code like this if there is a more readable way of writing it, but it's perfectly valid, and the f() call is reachable.