rust/tests/ui/offset-of/offset-of-dst-field.rs
est31 30c0e4e72b Add more tests for the offset_of!() macro
* ensuring that offset_of!(Self, ...) works iff inside an impl block
* ensuring that the output type is usize and doesn't coerce. this can be
  changed in the future, but if it is done, it should be a conscious descision
* improving the privacy checking test
* ensuring that generics don't let you escape the unsized check
2023-05-18 13:16:17 +02:00

49 lines
824 B
Rust

#![feature(offset_of, extern_types)]
use std::mem::offset_of;
struct Alpha {
x: u8,
y: u16,
z: [u8],
}
trait Trait {}
struct Beta {
x: u8,
y: u16,
z: dyn Trait,
}
extern {
type Extern;
}
struct Gamma {
x: u8,
y: u16,
z: Extern,
}
struct Delta<T: ?Sized> {
x: u8,
y: u16,
z: T,
}
fn main() {
offset_of!(Alpha, z); //~ ERROR the size for values of type
offset_of!(Beta, z); //~ ERROR the size for values of type
offset_of!(Gamma, z); //~ ERROR the size for values of type
}
fn delta() {
offset_of!(Delta<Alpha>, z); //~ ERROR the size for values of type
offset_of!(Delta<Extern>, z); //~ ERROR the size for values of type
}
fn generic_with_maybe_sized<T: ?Sized>() -> usize {
offset_of!(Delta<T>, z) //~ ERROR the size for values of type
}