src/test/run-pass/pushpop-unsafe-okay.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 // Basic sanity check for `push_unsafe!(EXPR)` and
  12 // `pop_unsafe!(EXPR)`: we can call unsafe code when there are a
  13 // positive number of pushes in the stack, or if we are within a
  14 // normal `unsafe` block, but otherwise cannot.
  15
  16 // ignore-pretty because the `push_unsafe!` and `pop_unsafe!` macros
  17 // are not integrated with the pretty-printer.
  18
  19 #![feature(pushpop_unsafe)]
  20
  21 static mut X: i32 = 0;
  22
  23 unsafe fn f() { X += 1; return; }
  24 fn g() { unsafe { X += 1_000; } return; }
  25
  26 fn check_reset_x(x: i32) -> bool {
  27     #![allow(unused_parens)] // dont you judge my style choices!
  28     unsafe {
  29         let ret = (x == X);
  30         X = 0;
  31         ret
  32     }
  33 }
  34
  35 fn main() {
  36     // double-check test infrastructure
  37     assert!(check_reset_x(0));
  38     unsafe { f(); }
  39     assert!(check_reset_x(1));
  40     assert!(check_reset_x(0));
  41     { g(); }
  42     assert!(check_reset_x(1000));
  43     assert!(check_reset_x(0));
  44     unsafe { f(); g(); g(); }
  45     assert!(check_reset_x(2001));
  46
  47     push_unsafe!( { f(); pop_unsafe!( g() ) } );
  48     assert!(check_reset_x(1_001));
  49     push_unsafe!( { g(); pop_unsafe!( unsafe { f(); f(); } ) } );
  50     assert!(check_reset_x(1_002));
  51
  52     unsafe { push_unsafe!( { f(); pop_unsafe!( { f(); f(); } ) } ); }
  53     assert!(check_reset_x(3));
  54     push_unsafe!( { f(); push_unsafe!( { pop_unsafe!( { f(); f(); f(); } ) } ); } );
  55     assert!(check_reset_x(4));
  56 }