rust/tests/ui/deriving/deriving-all-codegen.stdout

Ignoring revisions in .git-blame-ignore-revs. Click here to bypass and see the normal blame view.

1445 lines
49 KiB
Plaintext
Raw Normal View History

#![feature(prelude_import)]
//@ check-pass
//@ compile-flags: -Zunpretty=expanded
//@ edition:2021
//
// This test checks the code generated for all[*] the builtin derivable traits
// on a variety of structs and enums. It protects against accidental changes to
// the generated code, and makes deliberate changes to the generated code
// easier to review.
//
// [*] It excludes `Copy` in some cases, because that changes the code
// generated for `Clone`.
//
// [*] It excludes `RustcEncodable` and `RustDecodable`, which are obsolete and
// also require the `rustc_serialize` crate.
#![crate_type = "lib"]
#![allow(dead_code)]
#![allow(deprecated)]
#[prelude_import]
use std::prelude::rust_2021::*;
#[macro_use]
extern crate std;
// Empty struct.
struct Empty;
#[automatically_derived]
impl ::core::clone::Clone for Empty {
#[inline]
fn clone(&self) -> Empty { *self }
}
#[automatically_derived]
impl ::core::marker::Copy for Empty { }
#[automatically_derived]
impl ::core::fmt::Debug for Empty {
2023-11-08 22:36:43 +00:00
#[inline]
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
::core::fmt::Formatter::write_str(f, "Empty")
}
}
#[automatically_derived]
impl ::core::default::Default for Empty {
#[inline]
fn default() -> Empty { Empty {} }
}
#[automatically_derived]
impl ::core::hash::Hash for Empty {
#[inline]
fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {}
}
#[automatically_derived]
impl ::core::marker::StructuralPartialEq for Empty { }
#[automatically_derived]
impl ::core::cmp::PartialEq for Empty {
#[inline]
fn eq(&self, other: &Empty) -> bool { true }
}
#[automatically_derived]
impl ::core::cmp::Eq for Empty {
#[inline]
#[doc(hidden)]
2023-08-09 14:57:16 +00:00
#[coverage(off)]
fn assert_receiver_is_total_eq(&self) -> () {}
}
#[automatically_derived]
impl ::core::cmp::PartialOrd for Empty {
#[inline]
fn partial_cmp(&self, other: &Empty)
-> ::core::option::Option<::core::cmp::Ordering> {
::core::option::Option::Some(::core::cmp::Ordering::Equal)
}
}
#[automatically_derived]
impl ::core::cmp::Ord for Empty {
#[inline]
fn cmp(&self, other: &Empty) -> ::core::cmp::Ordering {
::core::cmp::Ordering::Equal
}
}
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
// A basic struct. Note: because this derives `Copy`, it gets the simple
// `clone` implemention that just does `*self`.
struct Point {
x: u32,
y: u32,
}
#[automatically_derived]
impl ::core::clone::Clone for Point {
#[inline]
fn clone(&self) -> Point {
let _: ::core::clone::AssertParamIsClone<u32>;
*self
}
}
#[automatically_derived]
impl ::core::marker::Copy for Point { }
#[automatically_derived]
impl ::core::fmt::Debug for Point {
2023-11-08 22:36:43 +00:00
#[inline]
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
::core::fmt::Formatter::debug_struct_field2_finish(f, "Point", "x",
&self.x, "y", &&self.y)
}
}
#[automatically_derived]
impl ::core::default::Default for Point {
#[inline]
fn default() -> Point {
Point {
x: ::core::default::Default::default(),
y: ::core::default::Default::default(),
}
}
}
#[automatically_derived]
impl ::core::hash::Hash for Point {
#[inline]
fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
::core::hash::Hash::hash(&self.x, state);
::core::hash::Hash::hash(&self.y, state)
}
}
#[automatically_derived]
impl ::core::marker::StructuralPartialEq for Point { }
#[automatically_derived]
impl ::core::cmp::PartialEq for Point {
#[inline]
fn eq(&self, other: &Point) -> bool {
self.x == other.x && self.y == other.y
}
}
#[automatically_derived]
impl ::core::cmp::Eq for Point {
#[inline]
#[doc(hidden)]
2023-08-09 14:57:16 +00:00
#[coverage(off)]
fn assert_receiver_is_total_eq(&self) -> () {
let _: ::core::cmp::AssertParamIsEq<u32>;
}
}
#[automatically_derived]
impl ::core::cmp::PartialOrd for Point {
#[inline]
fn partial_cmp(&self, other: &Point)
-> ::core::option::Option<::core::cmp::Ordering> {
match ::core::cmp::PartialOrd::partial_cmp(&self.x, &other.x) {
::core::option::Option::Some(::core::cmp::Ordering::Equal) =>
::core::cmp::PartialOrd::partial_cmp(&self.y, &other.y),
cmp => cmp,
}
}
}
#[automatically_derived]
impl ::core::cmp::Ord for Point {
#[inline]
fn cmp(&self, other: &Point) -> ::core::cmp::Ordering {
match ::core::cmp::Ord::cmp(&self.x, &other.x) {
::core::cmp::Ordering::Equal =>
::core::cmp::Ord::cmp(&self.y, &other.y),
cmp => cmp,
}
}
}
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
// A basic packed struct. Note: because this derives `Copy`, it gets the simple
// `clone` implemention that just does `*self`.
#[repr(packed)]
struct PackedPoint {
x: u32,
y: u32,
}
#[automatically_derived]
impl ::core::clone::Clone for PackedPoint {
#[inline]
fn clone(&self) -> PackedPoint {
let _: ::core::clone::AssertParamIsClone<u32>;
*self
}
}
#[automatically_derived]
impl ::core::marker::Copy for PackedPoint { }
#[automatically_derived]
impl ::core::fmt::Debug for PackedPoint {
2023-11-08 22:36:43 +00:00
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
::core::fmt::Formatter::debug_struct_field2_finish(f, "PackedPoint",
"x", &{ self.x }, "y", &&{ self.y })
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
}
}
#[automatically_derived]
impl ::core::default::Default for PackedPoint {
#[inline]
fn default() -> PackedPoint {
PackedPoint {
x: ::core::default::Default::default(),
y: ::core::default::Default::default(),
}
}
}
#[automatically_derived]
impl ::core::hash::Hash for PackedPoint {
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
::core::hash::Hash::hash(&{ self.x }, state);
::core::hash::Hash::hash(&{ self.y }, state)
}
}
#[automatically_derived]
impl ::core::marker::StructuralPartialEq for PackedPoint { }
#[automatically_derived]
impl ::core::cmp::PartialEq for PackedPoint {
#[inline]
fn eq(&self, other: &PackedPoint) -> bool {
({ self.x }) == ({ other.x }) && ({ self.y }) == ({ other.y })
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
}
}
#[automatically_derived]
impl ::core::cmp::Eq for PackedPoint {
#[inline]
#[doc(hidden)]
2023-08-09 14:57:16 +00:00
#[coverage(off)]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn assert_receiver_is_total_eq(&self) -> () {
let _: ::core::cmp::AssertParamIsEq<u32>;
}
}
#[automatically_derived]
impl ::core::cmp::PartialOrd for PackedPoint {
#[inline]
fn partial_cmp(&self, other: &PackedPoint)
-> ::core::option::Option<::core::cmp::Ordering> {
match ::core::cmp::PartialOrd::partial_cmp(&{ self.x }, &{ other.x })
{
::core::option::Option::Some(::core::cmp::Ordering::Equal) =>
::core::cmp::PartialOrd::partial_cmp(&{ self.y },
&{ other.y }),
cmp => cmp,
}
}
}
#[automatically_derived]
impl ::core::cmp::Ord for PackedPoint {
#[inline]
fn cmp(&self, other: &PackedPoint) -> ::core::cmp::Ordering {
match ::core::cmp::Ord::cmp(&{ self.x }, &{ other.x }) {
::core::cmp::Ordering::Equal =>
::core::cmp::Ord::cmp(&{ self.y }, &{ other.y }),
cmp => cmp,
}
}
}
// A large struct. Note: because this derives `Copy`, it gets the simple
// `clone` implemention that just does `*self`.
struct Big {
b1: u32,
b2: u32,
b3: u32,
b4: u32,
b5: u32,
b6: u32,
b7: u32,
b8: u32,
}
#[automatically_derived]
impl ::core::clone::Clone for Big {
#[inline]
fn clone(&self) -> Big {
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
let _: ::core::clone::AssertParamIsClone<u32>;
*self
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl ::core::marker::Copy for Big { }
#[automatically_derived]
impl ::core::fmt::Debug for Big {
2023-11-08 22:36:43 +00:00
#[inline]
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
let names: &'static _ =
&["b1", "b2", "b3", "b4", "b5", "b6", "b7", "b8"];
let values: &[&dyn ::core::fmt::Debug] =
&[&self.b1, &self.b2, &self.b3, &self.b4, &self.b5, &self.b6,
&self.b7, &&self.b8];
::core::fmt::Formatter::debug_struct_fields_finish(f, "Big", names,
values)
}
}
#[automatically_derived]
impl ::core::default::Default for Big {
#[inline]
fn default() -> Big {
Big {
b1: ::core::default::Default::default(),
b2: ::core::default::Default::default(),
b3: ::core::default::Default::default(),
b4: ::core::default::Default::default(),
b5: ::core::default::Default::default(),
b6: ::core::default::Default::default(),
b7: ::core::default::Default::default(),
b8: ::core::default::Default::default(),
}
}
}
#[automatically_derived]
impl ::core::hash::Hash for Big {
#[inline]
fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
::core::hash::Hash::hash(&self.b1, state);
::core::hash::Hash::hash(&self.b2, state);
::core::hash::Hash::hash(&self.b3, state);
::core::hash::Hash::hash(&self.b4, state);
::core::hash::Hash::hash(&self.b5, state);
::core::hash::Hash::hash(&self.b6, state);
::core::hash::Hash::hash(&self.b7, state);
::core::hash::Hash::hash(&self.b8, state)
}
}
#[automatically_derived]
impl ::core::marker::StructuralPartialEq for Big { }
#[automatically_derived]
impl ::core::cmp::PartialEq for Big {
#[inline]
fn eq(&self, other: &Big) -> bool {
self.b1 == other.b1 && self.b2 == other.b2 && self.b3 == other.b3 &&
self.b4 == other.b4 && self.b5 == other.b5 &&
self.b6 == other.b6 && self.b7 == other.b7 &&
self.b8 == other.b8
}
}
#[automatically_derived]
impl ::core::cmp::Eq for Big {
#[inline]
#[doc(hidden)]
2023-08-09 14:57:16 +00:00
#[coverage(off)]
fn assert_receiver_is_total_eq(&self) -> () {
let _: ::core::cmp::AssertParamIsEq<u32>;
}
}
#[automatically_derived]
impl ::core::cmp::PartialOrd for Big {
#[inline]
fn partial_cmp(&self, other: &Big)
-> ::core::option::Option<::core::cmp::Ordering> {
match ::core::cmp::PartialOrd::partial_cmp(&self.b1, &other.b1) {
::core::option::Option::Some(::core::cmp::Ordering::Equal) =>
match ::core::cmp::PartialOrd::partial_cmp(&self.b2,
&other.b2) {
::core::option::Option::Some(::core::cmp::Ordering::Equal)
=>
match ::core::cmp::PartialOrd::partial_cmp(&self.b3,
&other.b3) {
::core::option::Option::Some(::core::cmp::Ordering::Equal)
=>
match ::core::cmp::PartialOrd::partial_cmp(&self.b4,
&other.b4) {
::core::option::Option::Some(::core::cmp::Ordering::Equal)
=>
match ::core::cmp::PartialOrd::partial_cmp(&self.b5,
&other.b5) {
::core::option::Option::Some(::core::cmp::Ordering::Equal)
=>
match ::core::cmp::PartialOrd::partial_cmp(&self.b6,
&other.b6) {
::core::option::Option::Some(::core::cmp::Ordering::Equal)
=>
match ::core::cmp::PartialOrd::partial_cmp(&self.b7,
&other.b7) {
::core::option::Option::Some(::core::cmp::Ordering::Equal)
=>
::core::cmp::PartialOrd::partial_cmp(&self.b8, &other.b8),
cmp => cmp,
},
cmp => cmp,
},
cmp => cmp,
},
cmp => cmp,
},
cmp => cmp,
},
cmp => cmp,
},
cmp => cmp,
}
}
}
#[automatically_derived]
impl ::core::cmp::Ord for Big {
#[inline]
fn cmp(&self, other: &Big) -> ::core::cmp::Ordering {
match ::core::cmp::Ord::cmp(&self.b1, &other.b1) {
::core::cmp::Ordering::Equal =>
match ::core::cmp::Ord::cmp(&self.b2, &other.b2) {
::core::cmp::Ordering::Equal =>
match ::core::cmp::Ord::cmp(&self.b3, &other.b3) {
::core::cmp::Ordering::Equal =>
match ::core::cmp::Ord::cmp(&self.b4, &other.b4) {
::core::cmp::Ordering::Equal =>
match ::core::cmp::Ord::cmp(&self.b5, &other.b5) {
::core::cmp::Ordering::Equal =>
match ::core::cmp::Ord::cmp(&self.b6, &other.b6) {
::core::cmp::Ordering::Equal =>
match ::core::cmp::Ord::cmp(&self.b7, &other.b7) {
::core::cmp::Ordering::Equal =>
::core::cmp::Ord::cmp(&self.b8, &other.b8),
cmp => cmp,
},
cmp => cmp,
},
cmp => cmp,
},
cmp => cmp,
},
cmp => cmp,
},
cmp => cmp,
},
cmp => cmp,
}
}
}
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
// A struct that doesn't impl `Copy`, which means it gets the non-simple
// `clone` implemention that clones the fields individually.
struct NonCopy(u32);
#[automatically_derived]
impl ::core::clone::Clone for NonCopy {
#[inline]
fn clone(&self) -> NonCopy {
NonCopy(::core::clone::Clone::clone(&self.0))
}
}
// A packed struct that doesn't impl `Copy`, which means it gets the non-simple
// `clone` implemention that clones the fields individually.
#[repr(packed)]
struct PackedNonCopy(u32);
#[automatically_derived]
impl ::core::clone::Clone for PackedNonCopy {
#[inline]
fn clone(&self) -> PackedNonCopy {
PackedNonCopy(::core::clone::Clone::clone(&{ self.0 }))
}
}
// A struct that impls `Copy` manually, which means it gets the non-simple
// `clone` implemention that clones the fields individually.
struct ManualCopy(u32);
#[automatically_derived]
impl ::core::clone::Clone for ManualCopy {
#[inline]
fn clone(&self) -> ManualCopy {
ManualCopy(::core::clone::Clone::clone(&self.0))
}
}
impl Copy for ManualCopy {}
// A packed struct that impls `Copy` manually, which means it gets the
// non-simple `clone` implemention that clones the fields individually.
#[repr(packed)]
struct PackedManualCopy(u32);
#[automatically_derived]
impl ::core::clone::Clone for PackedManualCopy {
#[inline]
fn clone(&self) -> PackedManualCopy {
PackedManualCopy(::core::clone::Clone::clone(&{ self.0 }))
}
}
impl Copy for PackedManualCopy {}
// A struct with an unsized field. Some derives are not usable in this case.
struct Unsized([u32]);
#[automatically_derived]
impl ::core::fmt::Debug for Unsized {
2023-11-08 22:36:43 +00:00
#[inline]
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
::core::fmt::Formatter::debug_tuple_field1_finish(f, "Unsized",
&&self.0)
}
}
#[automatically_derived]
impl ::core::hash::Hash for Unsized {
#[inline]
fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
::core::hash::Hash::hash(&self.0, state)
}
}
#[automatically_derived]
impl ::core::marker::StructuralPartialEq for Unsized { }
#[automatically_derived]
impl ::core::cmp::PartialEq for Unsized {
#[inline]
fn eq(&self, other: &Unsized) -> bool { self.0 == other.0 }
}
#[automatically_derived]
impl ::core::cmp::Eq for Unsized {
#[inline]
#[doc(hidden)]
2023-08-09 14:57:16 +00:00
#[coverage(off)]
fn assert_receiver_is_total_eq(&self) -> () {
let _: ::core::cmp::AssertParamIsEq<[u32]>;
}
}
#[automatically_derived]
impl ::core::cmp::PartialOrd for Unsized {
#[inline]
fn partial_cmp(&self, other: &Unsized)
-> ::core::option::Option<::core::cmp::Ordering> {
::core::cmp::PartialOrd::partial_cmp(&self.0, &other.0)
}
}
#[automatically_derived]
impl ::core::cmp::Ord for Unsized {
#[inline]
fn cmp(&self, other: &Unsized) -> ::core::cmp::Ordering {
::core::cmp::Ord::cmp(&self.0, &other.0)
}
}
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
// A packed struct with an unsized `[u8]` field. This is currently allowed, but
// causes a warning and will be phased out at some point.
#[repr(packed)]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
struct PackedUnsizedU8([u8]);
#[automatically_derived]
impl ::core::fmt::Debug for PackedUnsizedU8 {
2023-11-08 22:36:43 +00:00
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
::core::fmt::Formatter::debug_tuple_field1_finish(f,
"PackedUnsizedU8", &&self.0)
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl ::core::hash::Hash for PackedUnsizedU8 {
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
::core::hash::Hash::hash(&self.0, state)
}
}
trait Trait {
type A;
}
// A generic struct involving an associated type.
struct Generic<T: Trait, U> {
t: T,
ta: T::A,
u: U,
}
#[automatically_derived]
impl<T: ::core::clone::Clone + Trait, U: ::core::clone::Clone>
::core::clone::Clone for Generic<T, U> where T::A: ::core::clone::Clone {
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn clone(&self) -> Generic<T, U> {
Generic {
t: ::core::clone::Clone::clone(&self.t),
ta: ::core::clone::Clone::clone(&self.ta),
u: ::core::clone::Clone::clone(&self.u),
}
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::marker::Copy + Trait, U: ::core::marker::Copy>
::core::marker::Copy for Generic<T, U> where T::A: ::core::marker::Copy {
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::fmt::Debug + Trait, U: ::core::fmt::Debug> ::core::fmt::Debug
for Generic<T, U> where T::A: ::core::fmt::Debug {
2023-11-08 22:36:43 +00:00
#[inline]
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
::core::fmt::Formatter::debug_struct_field3_finish(f, "Generic", "t",
&self.t, "ta", &self.ta, "u", &&self.u)
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::default::Default + Trait, U: ::core::default::Default>
::core::default::Default for Generic<T, U> where
T::A: ::core::default::Default {
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn default() -> Generic<T, U> {
Generic {
t: ::core::default::Default::default(),
ta: ::core::default::Default::default(),
u: ::core::default::Default::default(),
}
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::hash::Hash + Trait, U: ::core::hash::Hash> ::core::hash::Hash
for Generic<T, U> where T::A: ::core::hash::Hash {
#[inline]
fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
::core::hash::Hash::hash(&self.t, state);
::core::hash::Hash::hash(&self.ta, state);
::core::hash::Hash::hash(&self.u, state)
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: Trait, U> ::core::marker::StructuralPartialEq for Generic<T, U> { }
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::cmp::PartialEq + Trait, U: ::core::cmp::PartialEq>
::core::cmp::PartialEq for Generic<T, U> where
T::A: ::core::cmp::PartialEq {
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn eq(&self, other: &Generic<T, U>) -> bool {
self.t == other.t && self.ta == other.ta && self.u == other.u
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::cmp::Eq + Trait, U: ::core::cmp::Eq> ::core::cmp::Eq for
Generic<T, U> where T::A: ::core::cmp::Eq {
#[inline]
#[doc(hidden)]
2023-08-09 14:57:16 +00:00
#[coverage(off)]
fn assert_receiver_is_total_eq(&self) -> () {
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
let _: ::core::cmp::AssertParamIsEq<T>;
let _: ::core::cmp::AssertParamIsEq<T::A>;
let _: ::core::cmp::AssertParamIsEq<U>;
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::cmp::PartialOrd + Trait, U: ::core::cmp::PartialOrd>
::core::cmp::PartialOrd for Generic<T, U> where
T::A: ::core::cmp::PartialOrd {
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn partial_cmp(&self, other: &Generic<T, U>)
-> ::core::option::Option<::core::cmp::Ordering> {
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
match ::core::cmp::PartialOrd::partial_cmp(&self.t, &other.t) {
::core::option::Option::Some(::core::cmp::Ordering::Equal) =>
match ::core::cmp::PartialOrd::partial_cmp(&self.ta,
&other.ta) {
::core::option::Option::Some(::core::cmp::Ordering::Equal)
=> ::core::cmp::PartialOrd::partial_cmp(&self.u, &other.u),
cmp => cmp,
},
cmp => cmp,
}
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::cmp::Ord + Trait, U: ::core::cmp::Ord> ::core::cmp::Ord for
Generic<T, U> where T::A: ::core::cmp::Ord {
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn cmp(&self, other: &Generic<T, U>) -> ::core::cmp::Ordering {
match ::core::cmp::Ord::cmp(&self.t, &other.t) {
::core::cmp::Ordering::Equal =>
match ::core::cmp::Ord::cmp(&self.ta, &other.ta) {
::core::cmp::Ordering::Equal =>
::core::cmp::Ord::cmp(&self.u, &other.u),
cmp => cmp,
},
cmp => cmp,
}
}
}
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
// A packed, generic tuple struct involving an associated type. Because it is
// packed, a `T: Copy` bound is added to all impls (and where clauses within
// them) except for `Default`. This is because we must access fields using
// copies (e.g. `&{self.0}`), instead of using direct references (e.g.
// `&self.0`) which may be misaligned in a packed struct.
#[repr(packed)]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
struct PackedGeneric<T: Trait, U>(T, T::A, U);
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::clone::Clone + ::core::marker::Copy + Trait,
U: ::core::clone::Clone + ::core::marker::Copy> ::core::clone::Clone for
PackedGeneric<T, U> where T::A: ::core::clone::Clone +
::core::marker::Copy {
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn clone(&self) -> PackedGeneric<T, U> {
PackedGeneric(::core::clone::Clone::clone(&{ self.0 }),
::core::clone::Clone::clone(&{ self.1 }),
::core::clone::Clone::clone(&{ self.2 }))
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::marker::Copy + Trait, U: ::core::marker::Copy>
::core::marker::Copy for PackedGeneric<T, U> where
T::A: ::core::marker::Copy {
}
#[automatically_derived]
impl<T: ::core::fmt::Debug + ::core::marker::Copy + Trait,
U: ::core::fmt::Debug + ::core::marker::Copy> ::core::fmt::Debug for
PackedGeneric<T, U> where T::A: ::core::fmt::Debug + ::core::marker::Copy
{
2023-11-08 22:36:43 +00:00
#[inline]
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
::core::fmt::Formatter::debug_tuple_field3_finish(f, "PackedGeneric",
&{ self.0 }, &{ self.1 }, &&{ self.2 })
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::default::Default + Trait, U: ::core::default::Default>
::core::default::Default for PackedGeneric<T, U> where
T::A: ::core::default::Default {
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn default() -> PackedGeneric<T, U> {
PackedGeneric(::core::default::Default::default(),
::core::default::Default::default(),
::core::default::Default::default())
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::hash::Hash + ::core::marker::Copy + Trait,
U: ::core::hash::Hash + ::core::marker::Copy> ::core::hash::Hash for
PackedGeneric<T, U> where T::A: ::core::hash::Hash + ::core::marker::Copy
{
#[inline]
fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
::core::hash::Hash::hash(&{ self.0 }, state);
::core::hash::Hash::hash(&{ self.1 }, state);
::core::hash::Hash::hash(&{ self.2 }, state)
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: Trait, U> ::core::marker::StructuralPartialEq for PackedGeneric<T, U>
{
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::cmp::PartialEq + ::core::marker::Copy + Trait,
U: ::core::cmp::PartialEq + ::core::marker::Copy> ::core::cmp::PartialEq
for PackedGeneric<T, U> where T::A: ::core::cmp::PartialEq +
::core::marker::Copy {
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn eq(&self, other: &PackedGeneric<T, U>) -> bool {
({ self.0 }) == ({ other.0 }) && ({ self.1 }) == ({ other.1 }) &&
({ self.2 }) == ({ other.2 })
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::cmp::Eq + ::core::marker::Copy + Trait, U: ::core::cmp::Eq +
::core::marker::Copy> ::core::cmp::Eq for PackedGeneric<T, U> where
T::A: ::core::cmp::Eq + ::core::marker::Copy {
#[inline]
#[doc(hidden)]
2023-08-09 14:57:16 +00:00
#[coverage(off)]
fn assert_receiver_is_total_eq(&self) -> () {
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
let _: ::core::cmp::AssertParamIsEq<T>;
let _: ::core::cmp::AssertParamIsEq<T::A>;
let _: ::core::cmp::AssertParamIsEq<U>;
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::cmp::PartialOrd + ::core::marker::Copy + Trait,
U: ::core::cmp::PartialOrd + ::core::marker::Copy> ::core::cmp::PartialOrd
for PackedGeneric<T, U> where T::A: ::core::cmp::PartialOrd +
::core::marker::Copy {
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn partial_cmp(&self, other: &PackedGeneric<T, U>)
-> ::core::option::Option<::core::cmp::Ordering> {
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
match ::core::cmp::PartialOrd::partial_cmp(&{ self.0 }, &{ other.0 })
{
::core::option::Option::Some(::core::cmp::Ordering::Equal) =>
match ::core::cmp::PartialOrd::partial_cmp(&{ self.1 },
&{ other.1 }) {
::core::option::Option::Some(::core::cmp::Ordering::Equal)
=>
::core::cmp::PartialOrd::partial_cmp(&{ self.2 },
&{ other.2 }),
cmp => cmp,
},
cmp => cmp,
}
}
}
#[automatically_derived]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
impl<T: ::core::cmp::Ord + ::core::marker::Copy + Trait, U: ::core::cmp::Ord +
::core::marker::Copy> ::core::cmp::Ord for PackedGeneric<T, U> where
T::A: ::core::cmp::Ord + ::core::marker::Copy {
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn cmp(&self, other: &PackedGeneric<T, U>) -> ::core::cmp::Ordering {
match ::core::cmp::Ord::cmp(&{ self.0 }, &{ other.0 }) {
::core::cmp::Ordering::Equal =>
match ::core::cmp::Ord::cmp(&{ self.1 }, &{ other.1 }) {
::core::cmp::Ordering::Equal =>
::core::cmp::Ord::cmp(&{ self.2 }, &{ other.2 }),
cmp => cmp,
},
cmp => cmp,
}
}
}
// An empty enum.
enum Enum0 {}
#[automatically_derived]
impl ::core::clone::Clone for Enum0 {
#[inline]
fn clone(&self) -> Enum0 { *self }
}
#[automatically_derived]
impl ::core::marker::Copy for Enum0 { }
#[automatically_derived]
impl ::core::fmt::Debug for Enum0 {
2023-11-08 22:36:43 +00:00
#[inline]
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
match *self {}
}
}
#[automatically_derived]
impl ::core::hash::Hash for Enum0 {
#[inline]
fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
match *self {}
}
}
#[automatically_derived]
impl ::core::marker::StructuralPartialEq for Enum0 { }
#[automatically_derived]
impl ::core::cmp::PartialEq for Enum0 {
#[inline]
fn eq(&self, other: &Enum0) -> bool { match *self {} }
}
#[automatically_derived]
impl ::core::cmp::Eq for Enum0 {
#[inline]
#[doc(hidden)]
2023-08-09 14:57:16 +00:00
#[coverage(off)]
fn assert_receiver_is_total_eq(&self) -> () {}
}
#[automatically_derived]
impl ::core::cmp::PartialOrd for Enum0 {
#[inline]
fn partial_cmp(&self, other: &Enum0)
-> ::core::option::Option<::core::cmp::Ordering> {
match *self {}
}
}
#[automatically_derived]
impl ::core::cmp::Ord for Enum0 {
#[inline]
fn cmp(&self, other: &Enum0) -> ::core::cmp::Ordering { match *self {} }
}
// A single-variant enum.
enum Enum1 {
Single {
x: u32,
},
}
#[automatically_derived]
impl ::core::clone::Clone for Enum1 {
#[inline]
fn clone(&self) -> Enum1 {
match self {
Enum1::Single { x: __self_0 } =>
Enum1::Single { x: ::core::clone::Clone::clone(__self_0) },
}
}
}
#[automatically_derived]
impl ::core::fmt::Debug for Enum1 {
2023-11-08 22:36:43 +00:00
#[inline]
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
match self {
Enum1::Single { x: __self_0 } =>
::core::fmt::Formatter::debug_struct_field1_finish(f,
"Single", "x", &__self_0),
}
}
}
#[automatically_derived]
impl ::core::hash::Hash for Enum1 {
#[inline]
fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
match self {
Enum1::Single { x: __self_0 } =>
::core::hash::Hash::hash(__self_0, state),
}
}
}
#[automatically_derived]
impl ::core::marker::StructuralPartialEq for Enum1 { }
#[automatically_derived]
impl ::core::cmp::PartialEq for Enum1 {
#[inline]
fn eq(&self, other: &Enum1) -> bool {
match (self, other) {
(Enum1::Single { x: __self_0 }, Enum1::Single { x: __arg1_0 }) =>
*__self_0 == *__arg1_0,
}
}
}
#[automatically_derived]
impl ::core::cmp::Eq for Enum1 {
#[inline]
#[doc(hidden)]
2023-08-09 14:57:16 +00:00
#[coverage(off)]
fn assert_receiver_is_total_eq(&self) -> () {
let _: ::core::cmp::AssertParamIsEq<u32>;
}
}
#[automatically_derived]
impl ::core::cmp::PartialOrd for Enum1 {
#[inline]
fn partial_cmp(&self, other: &Enum1)
-> ::core::option::Option<::core::cmp::Ordering> {
match (self, other) {
(Enum1::Single { x: __self_0 }, Enum1::Single { x: __arg1_0 }) =>
::core::cmp::PartialOrd::partial_cmp(__self_0, __arg1_0),
}
}
}
#[automatically_derived]
impl ::core::cmp::Ord for Enum1 {
#[inline]
fn cmp(&self, other: &Enum1) -> ::core::cmp::Ordering {
match (self, other) {
(Enum1::Single { x: __self_0 }, Enum1::Single { x: __arg1_0 }) =>
::core::cmp::Ord::cmp(__self_0, __arg1_0),
}
}
}
// A C-like, fieldless enum with a single variant.
enum Fieldless1 {
#[default]
A,
}
#[automatically_derived]
impl ::core::clone::Clone for Fieldless1 {
#[inline]
fn clone(&self) -> Fieldless1 { Fieldless1::A }
}
#[automatically_derived]
impl ::core::fmt::Debug for Fieldless1 {
2023-11-08 22:36:43 +00:00
#[inline]
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
::core::fmt::Formatter::write_str(f, "A")
}
}
#[automatically_derived]
impl ::core::default::Default for Fieldless1 {
#[inline]
fn default() -> Fieldless1 { Self::A }
}
#[automatically_derived]
impl ::core::hash::Hash for Fieldless1 {
#[inline]
fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {}
}
#[automatically_derived]
impl ::core::marker::StructuralPartialEq for Fieldless1 { }
#[automatically_derived]
impl ::core::cmp::PartialEq for Fieldless1 {
#[inline]
fn eq(&self, other: &Fieldless1) -> bool { true }
}
#[automatically_derived]
impl ::core::cmp::Eq for Fieldless1 {
#[inline]
#[doc(hidden)]
2023-08-09 14:57:16 +00:00
#[coverage(off)]
fn assert_receiver_is_total_eq(&self) -> () {}
}
#[automatically_derived]
impl ::core::cmp::PartialOrd for Fieldless1 {
#[inline]
fn partial_cmp(&self, other: &Fieldless1)
-> ::core::option::Option<::core::cmp::Ordering> {
::core::option::Option::Some(::core::cmp::Ordering::Equal)
}
}
#[automatically_derived]
impl ::core::cmp::Ord for Fieldless1 {
#[inline]
fn cmp(&self, other: &Fieldless1) -> ::core::cmp::Ordering {
::core::cmp::Ordering::Equal
}
}
// A C-like, fieldless enum.
enum Fieldless {
#[default]
A,
B,
C,
}
#[automatically_derived]
impl ::core::clone::Clone for Fieldless {
#[inline]
fn clone(&self) -> Fieldless { *self }
}
#[automatically_derived]
impl ::core::marker::Copy for Fieldless { }
#[automatically_derived]
impl ::core::fmt::Debug for Fieldless {
2023-11-08 22:36:43 +00:00
#[inline]
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
::core::fmt::Formatter::write_str(f,
match self {
Fieldless::A => "A",
Fieldless::B => "B",
Fieldless::C => "C",
})
}
}
#[automatically_derived]
impl ::core::default::Default for Fieldless {
#[inline]
fn default() -> Fieldless { Self::A }
}
#[automatically_derived]
impl ::core::hash::Hash for Fieldless {
#[inline]
fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
let __self_tag = ::core::intrinsics::discriminant_value(self);
::core::hash::Hash::hash(&__self_tag, state)
}
}
#[automatically_derived]
impl ::core::marker::StructuralPartialEq for Fieldless { }
#[automatically_derived]
impl ::core::cmp::PartialEq for Fieldless {
#[inline]
fn eq(&self, other: &Fieldless) -> bool {
let __self_tag = ::core::intrinsics::discriminant_value(self);
let __arg1_tag = ::core::intrinsics::discriminant_value(other);
__self_tag == __arg1_tag
}
}
#[automatically_derived]
impl ::core::cmp::Eq for Fieldless {
#[inline]
#[doc(hidden)]
2023-08-09 14:57:16 +00:00
#[coverage(off)]
fn assert_receiver_is_total_eq(&self) -> () {}
}
#[automatically_derived]
impl ::core::cmp::PartialOrd for Fieldless {
#[inline]
fn partial_cmp(&self, other: &Fieldless)
-> ::core::option::Option<::core::cmp::Ordering> {
let __self_tag = ::core::intrinsics::discriminant_value(self);
let __arg1_tag = ::core::intrinsics::discriminant_value(other);
::core::cmp::PartialOrd::partial_cmp(&__self_tag, &__arg1_tag)
}
}
#[automatically_derived]
impl ::core::cmp::Ord for Fieldless {
#[inline]
fn cmp(&self, other: &Fieldless) -> ::core::cmp::Ordering {
let __self_tag = ::core::intrinsics::discriminant_value(self);
let __arg1_tag = ::core::intrinsics::discriminant_value(other);
::core::cmp::Ord::cmp(&__self_tag, &__arg1_tag)
}
}
// An enum with multiple fieldless and fielded variants.
enum Mixed {
#[default]
P,
Q,
R(u32),
S {
d1: Option<u32>,
d2: Option<i32>,
},
}
#[automatically_derived]
impl ::core::clone::Clone for Mixed {
#[inline]
fn clone(&self) -> Mixed {
let _: ::core::clone::AssertParamIsClone<u32>;
let _: ::core::clone::AssertParamIsClone<Option<u32>>;
let _: ::core::clone::AssertParamIsClone<Option<i32>>;
*self
}
}
#[automatically_derived]
impl ::core::marker::Copy for Mixed { }
#[automatically_derived]
impl ::core::fmt::Debug for Mixed {
2023-11-08 22:36:43 +00:00
#[inline]
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
match self {
Mixed::P => ::core::fmt::Formatter::write_str(f, "P"),
Mixed::Q => ::core::fmt::Formatter::write_str(f, "Q"),
Mixed::R(__self_0) =>
::core::fmt::Formatter::debug_tuple_field1_finish(f, "R",
&__self_0),
Mixed::S { d1: __self_0, d2: __self_1 } =>
::core::fmt::Formatter::debug_struct_field2_finish(f, "S",
"d1", __self_0, "d2", &__self_1),
}
}
}
#[automatically_derived]
impl ::core::default::Default for Mixed {
#[inline]
fn default() -> Mixed { Self::P }
}
#[automatically_derived]
impl ::core::hash::Hash for Mixed {
#[inline]
fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
let __self_tag = ::core::intrinsics::discriminant_value(self);
::core::hash::Hash::hash(&__self_tag, state);
match self {
Mixed::R(__self_0) => ::core::hash::Hash::hash(__self_0, state),
Mixed::S { d1: __self_0, d2: __self_1 } => {
::core::hash::Hash::hash(__self_0, state);
::core::hash::Hash::hash(__self_1, state)
}
_ => {}
}
}
}
#[automatically_derived]
impl ::core::marker::StructuralPartialEq for Mixed { }
#[automatically_derived]
impl ::core::cmp::PartialEq for Mixed {
#[inline]
fn eq(&self, other: &Mixed) -> bool {
let __self_tag = ::core::intrinsics::discriminant_value(self);
let __arg1_tag = ::core::intrinsics::discriminant_value(other);
__self_tag == __arg1_tag &&
match (self, other) {
(Mixed::R(__self_0), Mixed::R(__arg1_0)) =>
*__self_0 == *__arg1_0,
(Mixed::S { d1: __self_0, d2: __self_1 }, Mixed::S {
d1: __arg1_0, d2: __arg1_1 }) =>
*__self_0 == *__arg1_0 && *__self_1 == *__arg1_1,
_ => true,
}
}
}
#[automatically_derived]
impl ::core::cmp::Eq for Mixed {
#[inline]
#[doc(hidden)]
2023-08-09 14:57:16 +00:00
#[coverage(off)]
fn assert_receiver_is_total_eq(&self) -> () {
let _: ::core::cmp::AssertParamIsEq<u32>;
let _: ::core::cmp::AssertParamIsEq<Option<u32>>;
let _: ::core::cmp::AssertParamIsEq<Option<i32>>;
}
}
#[automatically_derived]
impl ::core::cmp::PartialOrd for Mixed {
#[inline]
fn partial_cmp(&self, other: &Mixed)
-> ::core::option::Option<::core::cmp::Ordering> {
let __self_tag = ::core::intrinsics::discriminant_value(self);
let __arg1_tag = ::core::intrinsics::discriminant_value(other);
match (self, other) {
(Mixed::R(__self_0), Mixed::R(__arg1_0)) =>
::core::cmp::PartialOrd::partial_cmp(__self_0, __arg1_0),
(Mixed::S { d1: __self_0, d2: __self_1 }, Mixed::S {
d1: __arg1_0, d2: __arg1_1 }) =>
match ::core::cmp::PartialOrd::partial_cmp(__self_0, __arg1_0)
{
::core::option::Option::Some(::core::cmp::Ordering::Equal)
=> ::core::cmp::PartialOrd::partial_cmp(__self_1, __arg1_1),
cmp => cmp,
},
_ =>
::core::cmp::PartialOrd::partial_cmp(&__self_tag,
&__arg1_tag),
}
}
}
#[automatically_derived]
impl ::core::cmp::Ord for Mixed {
#[inline]
fn cmp(&self, other: &Mixed) -> ::core::cmp::Ordering {
let __self_tag = ::core::intrinsics::discriminant_value(self);
let __arg1_tag = ::core::intrinsics::discriminant_value(other);
match ::core::cmp::Ord::cmp(&__self_tag, &__arg1_tag) {
::core::cmp::Ordering::Equal =>
match (self, other) {
(Mixed::R(__self_0), Mixed::R(__arg1_0)) =>
::core::cmp::Ord::cmp(__self_0, __arg1_0),
(Mixed::S { d1: __self_0, d2: __self_1 }, Mixed::S {
d1: __arg1_0, d2: __arg1_1 }) =>
match ::core::cmp::Ord::cmp(__self_0, __arg1_0) {
::core::cmp::Ordering::Equal =>
::core::cmp::Ord::cmp(__self_1, __arg1_1),
cmp => cmp,
},
_ => ::core::cmp::Ordering::Equal,
},
cmp => cmp,
}
}
}
// An enum with no fieldless variants. Note that `Default` cannot be derived
// for this enum.
enum Fielded { X(u32), Y(bool), Z(Option<i32>), }
#[automatically_derived]
impl ::core::clone::Clone for Fielded {
#[inline]
fn clone(&self) -> Fielded {
match self {
Fielded::X(__self_0) =>
Fielded::X(::core::clone::Clone::clone(__self_0)),
Fielded::Y(__self_0) =>
Fielded::Y(::core::clone::Clone::clone(__self_0)),
Fielded::Z(__self_0) =>
Fielded::Z(::core::clone::Clone::clone(__self_0)),
}
}
}
#[automatically_derived]
impl ::core::fmt::Debug for Fielded {
2023-11-08 22:36:43 +00:00
#[inline]
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
match self {
Fielded::X(__self_0) =>
::core::fmt::Formatter::debug_tuple_field1_finish(f, "X",
&__self_0),
Fielded::Y(__self_0) =>
::core::fmt::Formatter::debug_tuple_field1_finish(f, "Y",
&__self_0),
Fielded::Z(__self_0) =>
::core::fmt::Formatter::debug_tuple_field1_finish(f, "Z",
&__self_0),
}
}
}
#[automatically_derived]
impl ::core::hash::Hash for Fielded {
#[inline]
fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
let __self_tag = ::core::intrinsics::discriminant_value(self);
::core::hash::Hash::hash(&__self_tag, state);
match self {
Fielded::X(__self_0) => ::core::hash::Hash::hash(__self_0, state),
Fielded::Y(__self_0) => ::core::hash::Hash::hash(__self_0, state),
Fielded::Z(__self_0) => ::core::hash::Hash::hash(__self_0, state),
}
}
}
#[automatically_derived]
impl ::core::marker::StructuralPartialEq for Fielded { }
#[automatically_derived]
impl ::core::cmp::PartialEq for Fielded {
#[inline]
fn eq(&self, other: &Fielded) -> bool {
let __self_tag = ::core::intrinsics::discriminant_value(self);
let __arg1_tag = ::core::intrinsics::discriminant_value(other);
__self_tag == __arg1_tag &&
match (self, other) {
(Fielded::X(__self_0), Fielded::X(__arg1_0)) =>
*__self_0 == *__arg1_0,
(Fielded::Y(__self_0), Fielded::Y(__arg1_0)) =>
*__self_0 == *__arg1_0,
(Fielded::Z(__self_0), Fielded::Z(__arg1_0)) =>
*__self_0 == *__arg1_0,
_ => unsafe { ::core::intrinsics::unreachable() }
}
}
}
#[automatically_derived]
impl ::core::cmp::Eq for Fielded {
#[inline]
#[doc(hidden)]
2023-08-09 14:57:16 +00:00
#[coverage(off)]
fn assert_receiver_is_total_eq(&self) -> () {
let _: ::core::cmp::AssertParamIsEq<u32>;
let _: ::core::cmp::AssertParamIsEq<bool>;
let _: ::core::cmp::AssertParamIsEq<Option<i32>>;
}
}
#[automatically_derived]
impl ::core::cmp::PartialOrd for Fielded {
#[inline]
fn partial_cmp(&self, other: &Fielded)
-> ::core::option::Option<::core::cmp::Ordering> {
let __self_tag = ::core::intrinsics::discriminant_value(self);
let __arg1_tag = ::core::intrinsics::discriminant_value(other);
match (self, other) {
(Fielded::X(__self_0), Fielded::X(__arg1_0)) =>
::core::cmp::PartialOrd::partial_cmp(__self_0, __arg1_0),
(Fielded::Y(__self_0), Fielded::Y(__arg1_0)) =>
::core::cmp::PartialOrd::partial_cmp(__self_0, __arg1_0),
(Fielded::Z(__self_0), Fielded::Z(__arg1_0)) =>
::core::cmp::PartialOrd::partial_cmp(__self_0, __arg1_0),
_ =>
::core::cmp::PartialOrd::partial_cmp(&__self_tag,
&__arg1_tag),
}
}
}
#[automatically_derived]
impl ::core::cmp::Ord for Fielded {
#[inline]
fn cmp(&self, other: &Fielded) -> ::core::cmp::Ordering {
let __self_tag = ::core::intrinsics::discriminant_value(self);
let __arg1_tag = ::core::intrinsics::discriminant_value(other);
match ::core::cmp::Ord::cmp(&__self_tag, &__arg1_tag) {
::core::cmp::Ordering::Equal =>
match (self, other) {
(Fielded::X(__self_0), Fielded::X(__arg1_0)) =>
::core::cmp::Ord::cmp(__self_0, __arg1_0),
(Fielded::Y(__self_0), Fielded::Y(__arg1_0)) =>
::core::cmp::Ord::cmp(__self_0, __arg1_0),
(Fielded::Z(__self_0), Fielded::Z(__arg1_0)) =>
::core::cmp::Ord::cmp(__self_0, __arg1_0),
_ => unsafe { ::core::intrinsics::unreachable() }
},
cmp => cmp,
}
}
}
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
// A generic enum. Note that `Default` cannot be derived for this enum.
enum EnumGeneric<T, U> { One(T), Two(U), }
#[automatically_derived]
impl<T: ::core::clone::Clone, U: ::core::clone::Clone> ::core::clone::Clone
for EnumGeneric<T, U> {
#[inline]
fn clone(&self) -> EnumGeneric<T, U> {
match self {
EnumGeneric::One(__self_0) =>
EnumGeneric::One(::core::clone::Clone::clone(__self_0)),
EnumGeneric::Two(__self_0) =>
EnumGeneric::Two(::core::clone::Clone::clone(__self_0)),
}
}
}
#[automatically_derived]
impl<T: ::core::marker::Copy, U: ::core::marker::Copy> ::core::marker::Copy
for EnumGeneric<T, U> {
}
#[automatically_derived]
impl<T: ::core::fmt::Debug, U: ::core::fmt::Debug> ::core::fmt::Debug for
EnumGeneric<T, U> {
2023-11-08 22:36:43 +00:00
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
match self {
EnumGeneric::One(__self_0) =>
::core::fmt::Formatter::debug_tuple_field1_finish(f, "One",
&__self_0),
EnumGeneric::Two(__self_0) =>
::core::fmt::Formatter::debug_tuple_field1_finish(f, "Two",
&__self_0),
}
}
}
#[automatically_derived]
impl<T: ::core::hash::Hash, U: ::core::hash::Hash> ::core::hash::Hash for
EnumGeneric<T, U> {
#[inline]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {
let __self_tag = ::core::intrinsics::discriminant_value(self);
::core::hash::Hash::hash(&__self_tag, state);
match self {
EnumGeneric::One(__self_0) =>
::core::hash::Hash::hash(__self_0, state),
EnumGeneric::Two(__self_0) =>
::core::hash::Hash::hash(__self_0, state),
}
}
}
#[automatically_derived]
impl<T, U> ::core::marker::StructuralPartialEq for EnumGeneric<T, U> { }
#[automatically_derived]
impl<T: ::core::cmp::PartialEq, U: ::core::cmp::PartialEq>
::core::cmp::PartialEq for EnumGeneric<T, U> {
#[inline]
fn eq(&self, other: &EnumGeneric<T, U>) -> bool {
let __self_tag = ::core::intrinsics::discriminant_value(self);
let __arg1_tag = ::core::intrinsics::discriminant_value(other);
__self_tag == __arg1_tag &&
match (self, other) {
(EnumGeneric::One(__self_0), EnumGeneric::One(__arg1_0)) =>
*__self_0 == *__arg1_0,
(EnumGeneric::Two(__self_0), EnumGeneric::Two(__arg1_0)) =>
*__self_0 == *__arg1_0,
_ => unsafe { ::core::intrinsics::unreachable() }
}
}
}
#[automatically_derived]
impl<T: ::core::cmp::Eq, U: ::core::cmp::Eq> ::core::cmp::Eq for
EnumGeneric<T, U> {
#[inline]
#[doc(hidden)]
2023-08-09 14:57:16 +00:00
#[coverage(off)]
Allow more deriving on packed structs. Currently, deriving on packed structs has some non-trivial limitations, related to the fact that taking references on unaligned fields is UB. The current approach to field accesses in derived code: - Normal case: `&self.0` - In a packed struct that derives `Copy`: `&{self.0}` - In a packed struct that doesn't derive `Copy`: `&self.0` Plus, we disallow deriving any builtin traits other than `Default` for any packed generic type, because it's possible that there might be misaligned fields. This is a fairly broad restriction. Plus, we disallow deriving any builtin traits other than `Default` for most packed types that don't derive `Copy`. (The exceptions are those where the alignments inherently satisfy the packing, e.g. in a type with `repr(packed(N))` where all the fields have alignments of `N` or less anyway. Such types are pretty strange, because the `packed` attribute is not having any effect.) This commit introduces a new, simpler approach to field accesses: - Normal case: `&self.0` - In a packed struct: `&{self.0}` In the latter case, this requires that all fields impl `Copy`, which is a new restriction. This means that the following example compiles under the old approach and doesn't compile under the new approach. ``` #[derive(Debug)] struct NonCopy(u8); #[derive(Debug) #[repr(packed)] struct MyType(NonCopy); ``` (Note that the old approach's support for cases like this was brittle. Changing the `u8` to a `u16` would be enough to stop it working. So not much capability is lost here.) However, the other constraints from the old rules are removed. We can now derive builtin traits for packed generic structs like this: ``` trait Trait { type A; } #[derive(Hash)] #[repr(packed)] pub struct Foo<T: Trait>(T, T::A); ``` To allow this, we add a `T: Copy` bound in the derived impl and a `T::A: Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`. We can now also derive builtin traits for packed structs that don't derive `Copy`, so long as the fields impl `Copy`: ``` #[derive(Hash)] #[repr(packed)] pub struct Foo(u32); ``` This includes types that hand-impl `Copy` rather than deriving it, such as the following, that show up in winapi-0.2: ``` #[derive(Clone)] #[repr(packed)] struct MyType(i32); impl Copy for MyType {} ``` The new approach is simpler to understand and implement, and it avoids the need for the `unsafe_derive_on_repr_packed` check. One exception is required for backwards-compatibility: we allow `[u8]` fields for now. There is a new lint for this, `byte_slice_in_packed_struct_with_derive`.
2022-11-21 03:40:32 +00:00
fn assert_receiver_is_total_eq(&self) -> () {
let _: ::core::cmp::AssertParamIsEq<T>;
let _: ::core::cmp::AssertParamIsEq<U>;
}
}
#[automatically_derived]
impl<T: ::core::cmp::PartialOrd, U: ::core::cmp::PartialOrd>
::core::cmp::PartialOrd for EnumGeneric<T, U> {
#[inline]
fn partial_cmp(&self, other: &EnumGeneric<T, U>)
-> ::core::option::Option<::core::cmp::Ordering> {
let __self_tag = ::core::intrinsics::discriminant_value(self);
let __arg1_tag = ::core::intrinsics::discriminant_value(other);
match (self, other) {
(EnumGeneric::One(__self_0), EnumGeneric::One(__arg1_0)) =>
::core::cmp::PartialOrd::partial_cmp(__self_0, __arg1_0),
(EnumGeneric::Two(__self_0), EnumGeneric::Two(__arg1_0)) =>
::core::cmp::PartialOrd::partial_cmp(__self_0, __arg1_0),
_ =>
::core::cmp::PartialOrd::partial_cmp(&__self_tag,
&__arg1_tag),
}
}
}
#[automatically_derived]
impl<T: ::core::cmp::Ord, U: ::core::cmp::Ord> ::core::cmp::Ord for
EnumGeneric<T, U> {
#[inline]
fn cmp(&self, other: &EnumGeneric<T, U>) -> ::core::cmp::Ordering {
let __self_tag = ::core::intrinsics::discriminant_value(self);
let __arg1_tag = ::core::intrinsics::discriminant_value(other);
match ::core::cmp::Ord::cmp(&__self_tag, &__arg1_tag) {
::core::cmp::Ordering::Equal =>
match (self, other) {
(EnumGeneric::One(__self_0), EnumGeneric::One(__arg1_0)) =>
::core::cmp::Ord::cmp(__self_0, __arg1_0),
(EnumGeneric::Two(__self_0), EnumGeneric::Two(__arg1_0)) =>
::core::cmp::Ord::cmp(__self_0, __arg1_0),
_ => unsafe { ::core::intrinsics::unreachable() }
},
cmp => cmp,
}
}
}
// A union. Most builtin traits are not derivable for unions.
pub union Union {
pub b: bool,
pub u: u32,
pub i: i32,
}
#[automatically_derived]
impl ::core::clone::Clone for Union {
#[inline]
fn clone(&self) -> Union {
let _: ::core::clone::AssertParamIsCopy<Self>;
*self
}
}
#[automatically_derived]
impl ::core::marker::Copy for Union { }