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|
// Compiler:
//
// Run-time:
// stdout: 2
// 7
// 6
// 11
#![allow(internal_features, unused_attributes)]
#![feature(auto_traits, lang_items, no_core, intrinsics, rustc_attrs, track_caller)]
#![no_std]
#![no_core]
#![no_main]
/*
* Core
*/
// Because we don't have core yet.
#[lang = "sized"]
pub trait Sized {}
#[lang = "copy"]
trait Copy {
}
impl Copy for isize {}
impl Copy for *mut i32 {}
impl Copy for usize {}
impl Copy for u8 {}
impl Copy for i8 {}
impl Copy for i32 {}
#[lang = "receiver"]
trait Receiver {
}
#[lang = "freeze"]
pub(crate) unsafe auto trait Freeze {}
#[lang = "panic_location"]
struct PanicLocation {
file: &'static str,
line: u32,
column: u32,
}
mod libc {
#[link(name = "c")]
extern "C" {
pub fn puts(s: *const u8) -> i32;
pub fn fflush(stream: *mut i32) -> i32;
pub fn printf(format: *const i8, ...) -> i32;
pub static stdout: *mut i32;
}
}
mod intrinsics {
#[rustc_nounwind]
#[rustc_intrinsic]
#[rustc_intrinsic_must_be_overridden]
pub fn abort() -> ! {
loop {}
}
}
#[lang = "panic"]
#[track_caller]
#[no_mangle]
pub fn panic(_msg: &'static str) -> ! {
unsafe {
libc::puts("Panicking\0" as *const str as *const u8);
libc::fflush(libc::stdout);
intrinsics::abort();
}
}
#[lang = "add"]
trait Add<RHS = Self> {
type Output;
fn add(self, rhs: RHS) -> Self::Output;
}
impl Add for u8 {
type Output = Self;
fn add(self, rhs: Self) -> Self {
self + rhs
}
}
impl Add for i8 {
type Output = Self;
fn add(self, rhs: Self) -> Self {
self + rhs
}
}
impl Add for i32 {
type Output = Self;
fn add(self, rhs: Self) -> Self {
self + rhs
}
}
impl Add for usize {
type Output = Self;
fn add(self, rhs: Self) -> Self {
self + rhs
}
}
impl Add for isize {
type Output = Self;
fn add(self, rhs: Self) -> Self {
self + rhs
}
}
#[track_caller]
#[lang = "panic_const_add_overflow"]
pub fn panic_const_add_overflow() -> ! {
panic("attempt to add with overflow");
}
/*
* Code
*/
struct Test {
field: isize,
}
fn test(num: isize) -> Test {
Test {
field: num + 1,
}
}
fn update_num(num: &mut isize) {
*num = *num + 5;
}
#[no_mangle]
extern "C" fn main(argc: i32, _argv: *const *const u8) -> i32 {
let mut test = test(argc);
unsafe {
libc::printf(b"%ld\n\0" as *const u8 as *const i8, test.field);
}
update_num(&mut test.field);
unsafe {
libc::printf(b"%ld\n\0" as *const u8 as *const i8, test.field);
}
update_num(&mut argc);
unsafe {
libc::printf(b"%ld\n\0" as *const u8 as *const i8, argc);
}
let refe = &mut argc;
*refe = *refe + 5;
unsafe {
libc::printf(b"%ld\n\0" as *const u8 as *const i8, argc);
}
0
}
|
