rust/src/test/compile-fail/const-call.rs

// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

#![feature(const_fn)]

fn f(x: usize) -> usize {
    x
}

fn main() {
    let _ = [0; f(2)]; //~ ERROR constant evaluation error [E0080]
                       //~| non-constant path in constant expression
}