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// Copyright 2013-2014 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.
// ignore-android: FIXME(#10381)
// compile-flags:-g
// debugger:rbreak zzz
// debugger:run
// debugger:finish
// debugger:print simple
// check:$1 = {x = 10, y = 20}
// debugger:print noDestructor
// check:$2 = {a = {x = 10, y = 20}, guard = -1}
// debugger:print withDestructor
// check:$3 = {a = {x = 10, y = 20}, guard = -1}
// debugger:print nested
// check:$4 = {a = {a = {x = 7890, y = 9870}}}
#[allow(unused_variable)];
struct NoDestructor {
x: i32,
y: i64
}
struct WithDestructor {
x: i32,
y: i64
}
impl Drop for WithDestructor {
fn drop(&mut self) {}
}
struct NoDestructorGuarded {
a: NoDestructor,
guard: i64
}
struct WithDestructorGuarded {
a: WithDestructor,
guard: i64
}
struct NestedInner {
a: WithDestructor
}
impl Drop for NestedInner {
fn drop(&mut self) {}
}
struct NestedOuter {
a: NestedInner
}
// The compiler adds a 'destructed' boolean field to structs implementing Drop. This field is used
// at runtime to prevent drop() to be executed more than once (see middle::trans::adt).
// This field must be incorporated by the debug info generation. Otherwise the debugger assumes a
// wrong size/layout for the struct.
fn main() {
let simple = WithDestructor { x: 10, y: 20 };
let noDestructor = NoDestructorGuarded {
a: NoDestructor { x: 10, y: 20 },
guard: -1
};
// If the destructor flag field is not incorporated into the debug info for 'WithDestructor'
// then the debugger will have an invalid offset for the field 'guard' and thus should not be
// able to read its value correctly (dots are padding bytes, D is the boolean destructor flag):
//
// 64 bit
//
// NoDestructorGuarded = 0000....00000000FFFFFFFF
// <--------------><------>
// NoDestructor guard
//
//
// withDestructorGuarded = 0000....00000000D.......FFFFFFFF
// <--------------><------> // How debug info says it is
// WithDestructor guard
//
// <----------------------><------> // How it actually is
// WithDestructor guard
//
// 32 bit
//
// NoDestructorGuarded = 000000000000FFFFFFFF
// <----------><------>
// NoDestructor guard
//
//
// withDestructorGuarded = 000000000000D...FFFFFFFF
// <----------><------> // How debug info says it is
// WithDestructor guard
//
// <--------------><------> // How it actually is
// WithDestructor guard
//
let withDestructor = WithDestructorGuarded {
a: WithDestructor { x: 10, y: 20 },
guard: -1
};
// expected layout (64 bit) = xxxx....yyyyyyyyD.......D...
// <--WithDestructor------>
// <-------NestedInner-------->
// <-------NestedOuter-------->
let nested = NestedOuter { a: NestedInner { a: WithDestructor { x: 7890, y: 9870 } } };
zzz();
}
fn zzz() {()}
|
