src/test/compile-fail/dropck_no_diverge_on_nonregular_3.rs

   1 // Copyright 2015 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 // Issue 22443: Reject code using non-regular types that would
  12 // otherwise cause dropck to loop infinitely.
  13 //
  14 // This version is just checking that we still sanely handle a trivial
  15 // wrapper around the non-regular type. (It also demonstrates how the
  16 // error messages will report different types depending on which type
  17 // dropck is analyzing.)
  18
  19 use std::marker::PhantomData;
  20
  21 struct Digit<T> {
  22     elem: T
  23 }
  24
  25 struct Node<T:'static> { m: PhantomData<&'static T> }
  26
  27 enum FingerTree<T:'static> {
  28     Single(T),
  29     // According to the bug report, Digit before Box would infinite loop.
  30     Deep(
  31         Digit<T>,
  32         Box<FingerTree<Node<T>>>,
  33         )
  34 }
  35
  36 enum Wrapper<T:'static> {
  37     Simple,
  38     Other(FingerTree<T>),
  39 }
  40
  41 fn main() {
  42     let w = //~ ERROR overflow while adding drop-check rules for std::option
  43         Some(Wrapper::Simple::<u32>);
  44     //~^ ERROR overflow while adding drop-check rules for std::option::Option
  45     //~| ERROR overflow while adding drop-check rules for Wrapper
  46 }