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// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// this tests move up progration, which is not yet implemented
// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// Check codegen for assignments (`a = b`) where the left-hand-side is
// not yet initialized. Assignments tend to be absent in simple code,
// so subtle breakage in them can leave a quite hard-to-find trail of
// destruction.
// ignore-tidy-linelength
fn main() {
let nodrop_x = false;
let nodrop_y;
// Since boolean does not require drop, this can be a simple
// assignment:
nodrop_y = nodrop_x;
let drop_x : Option<Box<u32>> = None;
let drop_y;
// Since the type of `drop_y` has drop, we generate a `replace`
// terminator:
drop_y = drop_x;
}
// END RUST SOURCE
// START rustc.main.SimplifyCfg-initial.after.mir
// bb0: {
// StorageLive(_1);
// _1 = const false;
// FakeRead(ForLet, _1);
// StorageLive(_2);
// StorageLive(_3);
// _3 = _1;
// _2 = move _3;
// StorageDead(_3);
// StorageLive(_4);
// _4 = std::option::Option<std::boxed::Box<u32>>::None;
// FakeRead(ForLet, _4);
// AscribeUserType(_4, o, UserTypeProjection { base: Ty(Canonical { variables: [], value: std::option::Option<std::boxed::Box<u32>> }), projs: [] });
// StorageLive(_5);
// StorageLive(_6);
// _6 = move _4;
// replace(_5 <- move _6) -> [return: bb2, unwind: bb5];
// }
// ...
// bb2: {
// drop(_6) -> [return: bb6, unwind: bb4];
// }
// ...
// bb5: {
// drop(_6) -> bb4;
// }
// END rustc.main.SimplifyCfg-initial.after.mir
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