src/test/run-pass/rec-align-u32.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 // Issue #2303
  12
  13 #![feature(intrinsics)]
  14
  15 use std::mem;
  16
  17 mod rusti {
  18     extern "rust-intrinsic" {
  19         pub fn pref_align_of<T>() -> usize;
  20         pub fn min_align_of<T>() -> usize;
  21     }
  22 }
  23
  24 // This is the type with the questionable alignment
  25 #[derive(Debug)]
  26 struct Inner {
  27     c64: u32
  28 }
  29
  30 // This is the type that contains the type with the
  31 // questionable alignment, for testing
  32 #[derive(Debug)]
  33 struct Outer {
  34     c8: u8,
  35     t: Inner
  36 }
  37
  38
  39 #[cfg(any(target_arch = "x86", target_arch = "arm", target_arch = "aarch64"))]
  40 mod m {
  41     pub fn align() -> usize { 4 }
  42     pub fn size() -> usize { 8 }
  43 }
  44
  45 #[cfg(target_arch = "x86_64")]
  46 mod m {
  47     pub fn align() -> usize { 4 }
  48     pub fn size() -> usize { 8 }
  49 }
  50
  51 pub fn main() {
  52     unsafe {
  53         let x = Outer {c8: 22, t: Inner {c64: 44}};
  54
  55         // Send it through the shape code
  56         let y = format!("{:?}", x);
  57
  58         println!("align inner = {:?}", rusti::min_align_of::<Inner>());
  59         println!("size outer = {:?}", mem::size_of::<Outer>());
  60         println!("y = {:?}", y);
  61
  62         // per clang/gcc the alignment of `inner` is 4 on x86.
  63         assert_eq!(rusti::min_align_of::<Inner>(), m::align());
  64
  65         // per clang/gcc the size of `outer` should be 12
  66         // because `inner`s alignment was 4.
  67         assert_eq!(mem::size_of::<Outer>(), m::size());
  68
  69         assert_eq!(y, "Outer { c8: 22, t: Inner { c64: 44 } }".to_string());
  70     }
  71 }