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|
use std::mem::ManuallyDrop;
union U1 { // OK
a: u8,
}
union U2<T: Copy> { // OK
a: T,
}
union U22<T> { // OK
a: ManuallyDrop<T>,
}
union U23<T> { // OK
a: (ManuallyDrop<T>, i32),
}
union U24<T> { // OK
a: [ManuallyDrop<T>; 2],
}
union U3 {
a: String, //~ ERROR field must implement `Copy` or be wrapped in `ManuallyDrop<...>` to be used in a union
}
union U32 { // field that does not drop but is not `Copy`, either
a: std::cell::RefCell<i32>, //~ ERROR field must implement `Copy` or be wrapped in `ManuallyDrop<...>` to be used in a union
}
union U4<T> {
a: T, //~ ERROR field must implement `Copy` or be wrapped in `ManuallyDrop<...>` to be used in a union
}
union U5 { // Having a drop impl is OK
a: u8,
}
impl Drop for U5 {
fn drop(&mut self) {}
}
union U5Nested { // a nested union that drops is NOT OK
nest: U5, //~ ERROR field must implement `Copy` or be wrapped in `ManuallyDrop<...>` to be used in a union
}
union U5Nested2 { // for now we don't special-case empty arrays
nest: [U5; 0], //~ ERROR field must implement `Copy` or be wrapped in `ManuallyDrop<...>` to be used in a union
}
union U6 { // OK
s: &'static i32,
m: &'static mut i32,
}
union U7<T> { // OK
f: (&'static mut i32, ManuallyDrop<T>, i32),
}
union U8<T> { // OK
f1: [(&'static mut i32, i32); 8],
f2: [ManuallyDrop<T>; 2],
}
fn main() {}
|
