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// { dg-additional-options "-w" }
// { dg-output "mut_deref\r*\nfoobar: 123\r*\n" }
extern "C" {
fn printf(s: *const i8, ...);
}
#[lang = "sized"]
pub trait Sized {}
#[lang = "deref"]
pub trait Deref {
type Target;
fn deref(&self) -> &Self::Target;
}
#[lang = "deref_mut"]
pub trait DerefMut: Deref {
fn deref_mut(&mut self) -> &mut Self::Target;
}
impl<T> Deref for &T {
type Target = T;
fn deref(&self) -> &T {
*self
}
}
impl<T> Deref for &mut T {
type Target = T;
fn deref(&self) -> &T {
*self
}
}
pub struct Bar(i32);
impl Bar {
pub fn foobar(&mut self) -> i32 {
self.0
}
}
pub struct Foo<T>(T);
impl<T> Deref for Foo<T> {
type Target = T;
fn deref(&self) -> &Self::Target {
&self.0
}
}
impl<T> DerefMut for Foo<T> {
fn deref_mut(&mut self) -> &mut Self::Target {
unsafe {
let a = "mut_deref\n\0";
let b = a as *const str;
let c = b as *const i8;
printf(c);
}
&mut self.0
}
}
pub fn main() -> i32 {
let bar = Bar(123);
let mut foo: Foo<Bar> = Foo(bar);
let foobar = foo.foobar();
unsafe {
let a = "foobar: %i\n\0";
let b = a as *const str;
let c = b as *const i8;
printf(c, foobar);
}
foobar - 123
}
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