--- /dev/null
+#[no_mangle]
+pub fn cold_function(c: u8) {
+ println!("cold {}", c);
+}
+
+#[no_mangle]
+pub fn hot_function(c: u8) {
+ std::env::set_var(format!("var{}", c), format!("hot {}", c));
+}
+
+fn main() {
+ let arg = std::env::args().skip(1).next().unwrap();
+
+ for i in 0 .. 1000_000 {
+ let some_value = arg.as_bytes()[i % arg.len()];
+ if some_value == b'!' {
+ // This branch is never taken at runtime
+ cold_function(some_value);
+ } else {
+ hot_function(some_value);
+ }
+ }
+}