src/test/run-make/intrinsic-unreachable/exit-ret.rs

   1 // Copyright 2014 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 #![feature(asm)]
  12 #![crate_type="lib"]
  13
  14 #[deny(unreachable_code)]
  15 pub fn exit(n: usize) -> i32 {
  16     unsafe {
  17         // Pretend this asm is an exit() syscall.
  18         asm!("" :: "r"(n) :: "volatile");
  19         // Can't actually reach this point, but rustc doesn't know that.
  20     }
  21     // This return value is just here to generate some extra code for a return
  22     // value, making it easier for the test script to detect whether the
  23     // compiler deleted it.
  24     42
  25 }