src/test/mir-opt/nll/region-subtyping-basic.rs

   1 // Copyright 2012-2016 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 test for liveness constraints: the region (`R1`) that appears
  12 // in the type of `p` includes the points after `&v[0]` up to (but not
  13 // including) the call to `use_x`. The `else` branch is not included.
  14
  15 // compile-flags:-Zborrowck=mir -Zverbose
  16 //                              ^^^^^^^^^ force compiler to dump more region information
  17
  18 #![allow(warnings)]
  19
  20 fn use_x(_: usize) -> bool { true }
  21
  22 fn main() {
  23     let mut v = [1, 2, 3];
  24     let p = &v[0];
  25     let q = p;
  26     if true {
  27         use_x(*q);
  28     } else {
  29         use_x(22);
  30     }
  31 }
  32
  33 // END RUST SOURCE
  34 // START rustc.main.nll.0.mir
  35 // | '_#2r    | {bb2[0..=6], bb3[0..=1]}
  36 // | '_#3r    | {bb2[1..=6], bb3[0..=1]}
  37 // | '_#4r    | {bb2[5..=6], bb3[0..=1]}
  38 // END rustc.main.nll.0.mir
  39 // START rustc.main.nll.0.mir
  40 // let _6: &'_#4r usize;
  41 // ...
  42 // let _2: &'_#3r usize;
  43 // ...
  44 // _2 = &'_#2r _1[_3];
  45 // ...
  46 // _7 = _2;
  47 // ...
  48 // _6 = move _7;
  49 // END rustc.main.nll.0.mir