rust/src/test/compile-fail/pred-not-bool.rs

// -*- rust -*-
// xfail-boot
// xfail-stage0

// error-pattern: Non-boolean return type

// this checks that a pred with a non-bool return
// type is rejected, even if the pred is never used

pred bad(int a) -> int {
  ret 37;
}

fn main() {
}