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|
//@ revisions: e2015 e2024
//@[e2015] check-pass
//@[e2024] check-fail
//@[e2024] edition:2024
use std::{marker, mem, ptr};
fn main() {}
fn _zero() {
if false {
unsafe { mem::zeroed() }
//[e2015]~^ warn: never type fallback affects this call to an `unsafe` function
//[e2024]~^^ error: never type fallback affects this call to an `unsafe` function
//~| warn: this changes meaning in Rust 2024 and in a future release in all editions!
//[e2024]~| warning: the type `!` does not permit zero-initialization
} else {
return;
};
// no ; -> type is inferred without fallback
if true { unsafe { mem::zeroed() } } else { return }
}
fn _trans() {
if false {
unsafe {
struct Zst;
core::mem::transmute(Zst)
//[e2015]~^ warn: never type fallback affects this call to an `unsafe` function
//[e2024]~^^ error: never type fallback affects this call to an `unsafe` function
//~| warn: this changes meaning in Rust 2024 and in a future release in all editions!
}
} else {
return;
};
}
fn _union() {
if false {
union Union<T: Copy> {
a: (),
b: T,
}
unsafe { Union { a: () }.b }
//[e2015]~^ warn: never type fallback affects this union access
//[e2024]~^^ error: never type fallback affects this union access
//~| warn: this changes meaning in Rust 2024 and in a future release in all editions!
} else {
return;
};
}
fn _deref() {
if false {
unsafe { *ptr::from_ref(&()).cast() }
//[e2015]~^ warn: never type fallback affects this raw pointer dereference
//[e2024]~^^ error: never type fallback affects this raw pointer dereference
//~| warn: this changes meaning in Rust 2024 and in a future release in all editions!
} else {
return;
};
}
fn _only_generics() {
if false {
unsafe fn internally_create<T>(_: Option<T>) {
unsafe {
let _ = mem::zeroed::<T>();
}
}
// We need the option (and unwrap later) to call a function in a way,
// which makes it affected by the fallback, but without having it return anything
let x = None;
unsafe { internally_create(x) }
//[e2015]~^ warn: never type fallback affects this call to an `unsafe` function
//[e2024]~^^ error: never type fallback affects this call to an `unsafe` function
//~| warn: this changes meaning in Rust 2024 and in a future release in all editions!
x.unwrap()
} else {
return;
};
}
fn _stored_function() {
if false {
let zeroed = mem::zeroed;
//[e2015]~^ warn: never type fallback affects this `unsafe` function
//[e2024]~^^ error: never type fallback affects this `unsafe` function
//~| warn: this changes meaning in Rust 2024 and in a future release in all editions!
unsafe { zeroed() }
//[e2015]~^ warn: never type fallback affects this call to an `unsafe` function
//[e2024]~^^ error: never type fallback affects this call to an `unsafe` function
//~| warn: this changes meaning in Rust 2024 and in a future release in all editions!
} else {
return;
};
}
fn _only_generics_stored_function() {
if false {
unsafe fn internally_create<T>(_: Option<T>) {
unsafe {
let _ = mem::zeroed::<T>();
}
}
let x = None;
let f = internally_create;
//[e2015]~^ warn: never type fallback affects this `unsafe` function
//[e2024]~^^ error: never type fallback affects this `unsafe` function
//~| warn: this changes meaning in Rust 2024 and in a future release in all editions!
unsafe { f(x) }
x.unwrap()
} else {
return;
};
}
fn _method() {
struct S<T>(marker::PhantomData<T>);
impl<T> S<T> {
#[allow(unused)] // FIXME: the unused lint is probably incorrect here
unsafe fn create_out_of_thin_air(&self) -> T {
todo!()
}
}
if false {
unsafe {
S(marker::PhantomData).create_out_of_thin_air()
//[e2015]~^ warn: never type fallback affects this call to an `unsafe` method
//[e2024]~^^ error: never type fallback affects this call to an `unsafe` method
//~| warn: this changes meaning in Rust 2024 and in a future release in all editions!
}
} else {
return;
};
}
// Minimization of the famous `objc` crate issue
fn _objc() {
pub unsafe fn send_message<R>() -> Result<R, ()> {
Ok(unsafe { core::mem::zeroed() })
}
macro_rules! msg_send {
() => {
match send_message::<_ /* ?0 */>() {
//[e2015]~^ warn: never type fallback affects this call to an `unsafe` function
//[e2024]~^^ error: never type fallback affects this call to an `unsafe` function
//~| warn: this changes meaning in Rust 2024 and in a future release in all editions!
Ok(x) => x,
Err(_) => loop {},
}
};
}
unsafe {
msg_send!();
}
}
|
