rust/src/test/debuginfo/struct-style-enum.rs
Michael Woerister eea329b0f7 debuginfo: Make DWARF representation of enums uniform.
So far the DWARF information for enums was different
for regular enums, univariant enums, Option-like enums,
etc. Regular enums were encoded as unions of structs,
while the other variants were encoded as bare structs.

With the changes in this PR all enums are encoded as
unions so that debuggers can reconstruct if something
originally was a struct, a univariant enum, or an
Option-like enum. For the latter case, information
about the Null variant is encoded into the union field
name. This information can then be used by the
debugger to print a None value actually as None
instead of Some(0x0).
2014-05-29 14:21:03 +02:00

77 lines
2.9 KiB
Rust

// 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-tidy-linelength
// ignore-android: FIXME(#10381)
// compile-flags:-g
// gdb-command:set print union on
// gdb-command:rbreak zzz
// gdb-command:run
// gdb-command:finish
// gdb-command:print case1
// gdb-check:$1 = {{Case1, a = 0, b = 31868, c = 31868, d = 31868, e = 31868}, {Case1, a = 0, b = 2088533116, c = 2088533116}, {Case1, a = 0, b = 8970181431921507452}}
// gdb-command:print case2
// gdb-check:$2 = {{Case2, a = 0, b = 4369, c = 4369, d = 4369, e = 4369}, {Case2, a = 0, b = 286331153, c = 286331153}, {Case2, a = 0, b = 1229782938247303441}}
// gdb-command:print case3
// gdb-check:$3 = {{Case3, a = 0, b = 22873, c = 22873, d = 22873, e = 22873}, {Case3, a = 0, b = 1499027801, c = 1499027801}, {Case3, a = 0, b = 6438275382588823897}}
// gdb-command:print univariant
// gdb-check:$4 = {{a = -1}}
#![allow(unused_variable)]
#![feature(struct_variant)]
// The first element is to ensure proper alignment, irrespective of the machines word size. Since
// the size of the discriminant value is machine dependent, this has be taken into account when
// datatype layout should be predictable as in this case.
enum Regular {
Case1 { a: u64, b: u16, c: u16, d: u16, e: u16},
Case2 { a: u64, b: u32, c: u32},
Case3 { a: u64, b: u64 }
}
enum Univariant {
TheOnlyCase { a: i64 }
}
fn main() {
// In order to avoid endianess trouble all of the following test values consist of a single
// repeated byte. This way each interpretation of the union should look the same, no matter if
// this is a big or little endian machine.
// 0b0111110001111100011111000111110001111100011111000111110001111100 = 8970181431921507452
// 0b01111100011111000111110001111100 = 2088533116
// 0b0111110001111100 = 31868
// 0b01111100 = 124
let case1 = Case1 { a: 0, b: 31868, c: 31868, d: 31868, e: 31868 };
// 0b0001000100010001000100010001000100010001000100010001000100010001 = 1229782938247303441
// 0b00010001000100010001000100010001 = 286331153
// 0b0001000100010001 = 4369
// 0b00010001 = 17
let case2 = Case2 { a: 0, b: 286331153, c: 286331153 };
// 0b0101100101011001010110010101100101011001010110010101100101011001 = 6438275382588823897
// 0b01011001010110010101100101011001 = 1499027801
// 0b0101100101011001 = 22873
// 0b01011001 = 89
let case3 = Case3 { a: 0, b: 6438275382588823897 };
let univariant = TheOnlyCase { a: -1 };
zzz();
}
fn zzz() {()}