1#version 450
2
3layout(location =0 ) in int c;
4layout(location =0 ) out int o;
5
6void main() {
7  int i = 0;
8  o = 1;
9  do {
10    o = 2;
11    return;
12    o = 3;
13  } while(i++ < 5);
14
15  // All this is a dead merge block.
16  o = 4;
17  if (c==4) {
18     o = 100;
19  } else {
20     o = 200;
21  }
22  o = 300;
23}
24