1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
|
#![allow(dead_code)]
#![warn(clippy::expl_impl_clone_on_copy)]
#[derive(Copy)]
struct Qux;
impl Clone for Qux {
fn clone(&self) -> Self {
Qux
}
}
// looks like unions don't support deriving Clone for now
#[derive(Copy)]
union Union {
a: u8,
}
impl Clone for Union {
fn clone(&self) -> Self {
Union { a: 42 }
}
}
// See #666
#[derive(Copy)]
struct Lt<'a> {
a: &'a u8,
}
impl<'a> Clone for Lt<'a> {
fn clone(&self) -> Self {
unimplemented!()
}
}
#[derive(Copy)]
struct BigArray {
a: [u8; 65],
}
impl Clone for BigArray {
fn clone(&self) -> Self {
unimplemented!()
}
}
#[derive(Copy)]
struct FnPtr {
a: fn() -> !,
}
impl Clone for FnPtr {
fn clone(&self) -> Self {
unimplemented!()
}
}
// Ok, Clone trait impl doesn't have constrained generics.
#[derive(Copy)]
struct Generic<T> {
a: T,
}
impl<T> Clone for Generic<T> {
fn clone(&self) -> Self {
unimplemented!()
}
}
#[derive(Copy)]
struct Generic2<T>(T);
impl<T: Clone> Clone for Generic2<T> {
fn clone(&self) -> Self {
Self(self.0.clone())
}
}
// Ok, Clone trait impl doesn't have constrained generics.
#[derive(Copy)]
struct GenericRef<'a, T, U>(T, &'a U);
impl<T: Clone, U> Clone for GenericRef<'_, T, U> {
fn clone(&self) -> Self {
Self(self.0.clone(), self.1)
}
}
// https://github.com/rust-lang/rust-clippy/issues/10188
#[repr(packed)]
#[derive(Copy)]
struct Packed<T>(T);
impl<T: Copy> Clone for Packed<T> {
fn clone(&self) -> Self {
*self
}
}
fn main() {}
|
