src/test/codegen-units/item-collection/unsizing.rs

   1 // Copyright 2012-2015 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 // ignore-tidy-linelength
  12 // compile-flags:-Zprint-mono-items=eager
  13 // compile-flags:-Zinline-in-all-cgus
  14
  15 #![deny(dead_code)]
  16 #![feature(coerce_unsized)]
  17 #![feature(unsize)]
  18 #![feature(start)]
  19
  20 use std::marker::Unsize;
  21 use std::ops::CoerceUnsized;
  22
  23 trait Trait {
  24     fn foo(&self);
  25 }
  26
  27 // Simple Case
  28 impl Trait for bool {
  29     fn foo(&self) {}
  30 }
  31
  32 impl Trait for char {
  33     fn foo(&self) {}
  34 }
  35
  36 // Struct Field Case
  37 struct Struct<T: ?Sized> {
  38     _a: u32,
  39     _b: i32,
  40     _c: T
  41 }
  42
  43 impl Trait for f64 {
  44     fn foo(&self) {}
  45 }
  46
  47 // Custom Coercion Case
  48 impl Trait for u32 {
  49     fn foo(&self) {}
  50 }
  51
  52 #[derive(Clone, Copy)]
  53 struct Wrapper<T: ?Sized>(*const T);
  54
  55 impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<Wrapper<U>> for Wrapper<T> {}
  56
  57 //~ MONO_ITEM fn unsizing::start[0]
  58 #[start]
  59 fn start(_: isize, _: *const *const u8) -> isize {
  60     // simple case
  61     let bool_sized = &true;
  62     //~ MONO_ITEM fn core::ptr[0]::drop_in_place[0]<bool> @@ unsizing0[Internal]
  63     //~ MONO_ITEM fn unsizing::{{impl}}[0]::foo[0]
  64     let _bool_unsized = bool_sized as &Trait;
  65
  66     let char_sized = &'a';
  67
  68     //~ MONO_ITEM fn core::ptr[0]::drop_in_place[0]<char> @@ unsizing0[Internal]
  69     //~ MONO_ITEM fn unsizing::{{impl}}[1]::foo[0]
  70     let _char_unsized = char_sized as &Trait;
  71
  72     // struct field
  73     let struct_sized = &Struct {
  74         _a: 1,
  75         _b: 2,
  76         _c: 3.0f64
  77     };
  78     //~ MONO_ITEM fn core::ptr[0]::drop_in_place[0]<f64> @@ unsizing0[Internal]
  79     //~ MONO_ITEM fn unsizing::{{impl}}[2]::foo[0]
  80     let _struct_unsized = struct_sized as &Struct<Trait>;
  81
  82     // custom coercion
  83     let wrapper_sized = Wrapper(&0u32);
  84     //~ MONO_ITEM fn core::ptr[0]::drop_in_place[0]<u32> @@ unsizing0[Internal]
  85     //~ MONO_ITEM fn unsizing::{{impl}}[3]::foo[0]
  86     let _wrapper_sized = wrapper_sized as Wrapper<Trait>;
  87
  88     0
  89 }