#include <metal_stdlib>

using namespace metal;

#define TINT_ISOLATE_UB(VOLATILE_NAME) \
  volatile bool VOLATILE_NAME = true; \
  if (VOLATILE_NAME)

int f() {
  int i = 0;
  TINT_ISOLATE_UB(tint_volatile_true) while((i < 4)) {
    i = as_type<int>((as_type<uint>(i) + as_type<uint>(1)));
  }
  return i;
}