From 06ef2e72c9724e89057f9d3a9ba50e1ce78da40d Mon Sep 17 00:00:00 2001 From: Oliver Schneider Date: Fri, 29 Jan 2016 15:44:16 +0100 Subject: [PATCH 1/2] [MIR] Fix type of temporary for `box EXPR` Previously the code would fail to dereference the temporary. --- src/librustc_mir/build/expr/as_rvalue.rs | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/src/librustc_mir/build/expr/as_rvalue.rs b/src/librustc_mir/build/expr/as_rvalue.rs index c389e8e733091..e556d707a2d48 100644 --- a/src/librustc_mir/build/expr/as_rvalue.rs +++ b/src/librustc_mir/build/expr/as_rvalue.rs @@ -61,16 +61,15 @@ impl<'a,'tcx> Builder<'a,'tcx> { } ExprKind::Box { value } => { let value = this.hir.mirror(value); - let value_ty = value.ty.clone(); - let result = this.temp(value_ty.clone()); + let result = this.temp(expr.ty); // to start, malloc some memory of suitable type (thus far, uninitialized): - let rvalue = Rvalue::Box(value.ty.clone()); + let rvalue = Rvalue::Box(value.ty); this.cfg.push_assign(block, expr_span, &result, rvalue); // schedule a shallow free of that memory, lest we unwind: let extent = this.extent_of_innermost_scope(); - this.schedule_drop(expr_span, extent, DropKind::Free, &result, value_ty); + this.schedule_drop(expr_span, extent, DropKind::Free, &result, value.ty); // initialize the box contents: let contents = result.clone().deref(); From 9b81d03114b54d9dbc594d558c907f3c5efd53be Mon Sep 17 00:00:00 2001 From: Simonas Kazlauskas Date: Thu, 28 Jan 2016 20:27:19 +0200 Subject: [PATCH 2/2] [MIR] Add test for `box EXPR` dereferencing --- src/test/run-pass/mir_boxing.rs | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) create mode 100644 src/test/run-pass/mir_boxing.rs diff --git a/src/test/run-pass/mir_boxing.rs b/src/test/run-pass/mir_boxing.rs new file mode 100644 index 0000000000000..1d635e9f778df --- /dev/null +++ b/src/test/run-pass/mir_boxing.rs @@ -0,0 +1,20 @@ +// Copyright 2016 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +#![feature(rustc_attrs, box_syntax)] + +#[rustc_mir] +fn test() -> Box { + box 42 +} + +fn main() { + assert_eq!(*test(), 42); +}