mirror of
https://github.com/rust-lang/rust.git
synced 2025-09-28 13:46:03 +00:00
28 lines
1.4 KiB
Rust
28 lines
1.4 KiB
Rust
//! `#![feature(unsized_fn_params)]` lets you use unsized function parameters. In particular this
|
|
//! is load bearing for `Box<dyn FnOnce()>: FnOnce()`. To do that, borrowck relaxes the requirement
|
|
//! that certain places must be `Sized`. But in #142911 we removed alloca support, so these
|
|
//! arguments cannot be put in temporaries (or ICE at codegen) That means when `unsized_fn_params`
|
|
//! is enabled, we must explicitly check that unsized function arguments are place expressions.
|
|
//!
|
|
//! Also see tests/ui/unsized_locals/unsized-exprs-rpass.rs
|
|
|
|
#![feature(unsized_fn_params)]
|
|
|
|
fn foo() -> Box<[u8]> {
|
|
Box::new(*b"foo")
|
|
}
|
|
|
|
fn udrop<T: ?Sized>(_x: T) {}
|
|
|
|
fn main(){
|
|
// NB The ordering of the following operations matters, otherwise errors get swallowed somehow.
|
|
|
|
udrop::<[u8]>(if true { *foo() } else { *foo() }); //~ERROR the size for values of type `[u8]` cannot be known at compilation time
|
|
udrop::<[u8]>({ *foo() }); //~ERROR the size for values of type `[u8]` cannot be known at compilation time
|
|
udrop(match foo() { x => *x }); //~ERROR the size for values of type `[u8]` cannot be known at compilation time
|
|
udrop::<[u8]>({ loop { break *foo(); } }); //~ERROR the size for values of type `[u8]` cannot be known at compilation time
|
|
|
|
{ *foo() }; //~ERROR the size for values of type `[u8]` cannot be known at compilation time
|
|
{ loop { break *foo(); } }; //~ERROR the size for values of type `[u8]` cannot be known at compilation time
|
|
}
|