diff --git a/compiler/rustc_error_codes/src/error_codes/E0206.md b/compiler/rustc_error_codes/src/error_codes/E0206.md
index da53b671ad0cc..4405a2149ceb8 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0206.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0206.md
@@ -4,15 +4,12 @@ enum.
Erroneous code example:
```compile_fail,E0206
-type Foo = [u8; 256];
-impl Copy for Foo { } // error!
-
#[derive(Copy, Clone)]
struct Bar;
impl Copy for &'static mut Bar { } // error!
```
-You can only implement `Copy` for a struct or an enum. Both of the previous
-examples will fail, because neither `[u8; 256]` nor `&'static mut Bar`
-(mutable reference to `Bar`) is a struct or enum.
+You can only implement `Copy` for a struct or an enum.
+The previous example will fail because `&'static mut Bar`
+is not a struct or enum.
diff --git a/compiler/rustc_mir_transform/src/shim.rs b/compiler/rustc_mir_transform/src/shim.rs
index f2ea5fedc625c..f59aaa664f3ad 100644
--- a/compiler/rustc_mir_transform/src/shim.rs
+++ b/compiler/rustc_mir_transform/src/shim.rs
@@ -310,7 +310,6 @@ fn build_clone_shim<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, self_ty: Ty<'tcx>) -
match self_ty.kind() {
_ if is_copy => builder.copy_shim(),
- ty::Array(ty, len) => builder.array_shim(dest, src, ty, len),
ty::Closure(_, substs) => {
builder.tuple_like_shim(dest, src, substs.as_closure().upvar_tys())
}
@@ -459,154 +458,6 @@ impl CloneShimBuilder<'tcx> {
);
}
- fn loop_header(
- &mut self,
- beg: Place<'tcx>,
- end: Place<'tcx>,
- loop_body: BasicBlock,
- loop_end: BasicBlock,
- is_cleanup: bool,
- ) {
- let tcx = self.tcx;
-
- let cond = self.make_place(Mutability::Mut, tcx.types.bool);
- let compute_cond = self.make_statement(StatementKind::Assign(Box::new((
- cond,
- Rvalue::BinaryOp(BinOp::Ne, Box::new((Operand::Copy(end), Operand::Copy(beg)))),
- ))));
-
- // `if end != beg { goto loop_body; } else { goto loop_end; }`
- self.block(
- vec![compute_cond],
- TerminatorKind::if_(tcx, Operand::Move(cond), loop_body, loop_end),
- is_cleanup,
- );
- }
-
- fn make_usize(&self, value: u64) -> Box<Constant<'tcx>> {
- Box::new(Constant {
- span: self.span,
- user_ty: None,
- literal: ty::Const::from_usize(self.tcx, value).into(),
- })
- }
-
- fn array_shim(
- &mut self,
- dest: Place<'tcx>,
- src: Place<'tcx>,
- ty: Ty<'tcx>,
- len: &'tcx ty::Const<'tcx>,
- ) {
- let tcx = self.tcx;
- let span = self.span;
-
- let beg = self.local_decls.push(LocalDecl::new(tcx.types.usize, span));
- let end = self.make_place(Mutability::Not, tcx.types.usize);
-
- // BB #0
- // `let mut beg = 0;`
- // `let end = len;`
- // `goto #1;`
- let inits = vec![
- self.make_statement(StatementKind::Assign(Box::new((
- Place::from(beg),
- Rvalue::Use(Operand::Constant(self.make_usize(0))),
- )))),
- self.make_statement(StatementKind::Assign(Box::new((
- end,
- Rvalue::Use(Operand::Constant(Box::new(Constant {
- span: self.span,
- user_ty: None,
- literal: len.into(),
- }))),
- )))),
- ];
- self.block(inits, TerminatorKind::Goto { target: BasicBlock::new(1) }, false);
-
- // BB #1: loop {
- // BB #2;
- // BB #3;
- // }
- // BB #4;
- self.loop_header(Place::from(beg), end, BasicBlock::new(2), BasicBlock::new(4), false);
-
- // BB #2
- // `dest[i] = Clone::clone(src[beg])`;
- // Goto #3 if ok, #5 if unwinding happens.
- let dest_field = self.tcx.mk_place_index(dest, beg);
- let src_field = self.tcx.mk_place_index(src, beg);
- self.make_clone_call(dest_field, src_field, ty, BasicBlock::new(3), BasicBlock::new(5));
-
- // BB #3
- // `beg = beg + 1;`
- // `goto #1`;
- let statements = vec![self.make_statement(StatementKind::Assign(Box::new((
- Place::from(beg),
- Rvalue::BinaryOp(
- BinOp::Add,
- Box::new((Operand::Copy(Place::from(beg)), Operand::Constant(self.make_usize(1)))),
- ),
- ))))];
- self.block(statements, TerminatorKind::Goto { target: BasicBlock::new(1) }, false);
-
- // BB #4
- // `return dest;`
- self.block(vec![], TerminatorKind::Return, false);
-
- // BB #5 (cleanup)
- // `let end = beg;`
- // `let mut beg = 0;`
- // goto #6;
- let end = beg;
- let beg = self.local_decls.push(LocalDecl::new(tcx.types.usize, span));
- let init = self.make_statement(StatementKind::Assign(Box::new((
- Place::from(beg),
- Rvalue::Use(Operand::Constant(self.make_usize(0))),
- ))));
- self.block(vec![init], TerminatorKind::Goto { target: BasicBlock::new(6) }, true);
-
- // BB #6 (cleanup): loop {
- // BB #7;
- // BB #8;
- // }
- // BB #9;
- self.loop_header(
- Place::from(beg),
- Place::from(end),
- BasicBlock::new(7),
- BasicBlock::new(9),
- true,
- );
-
- // BB #7 (cleanup)
- // `drop(dest[beg])`;
- self.block(
- vec![],
- TerminatorKind::Drop {
- place: self.tcx.mk_place_index(dest, beg),
- target: BasicBlock::new(8),
- unwind: None,
- },
- true,
- );
-
- // BB #8 (cleanup)
- // `beg = beg + 1;`
- // `goto #6;`
- let statement = self.make_statement(StatementKind::Assign(Box::new((
- Place::from(beg),
- Rvalue::BinaryOp(
- BinOp::Add,
- Box::new((Operand::Copy(Place::from(beg)), Operand::Constant(self.make_usize(1)))),
- ),
- ))));
- self.block(vec![statement], TerminatorKind::Goto { target: BasicBlock::new(6) }, true);
-
- // BB #9 (resume)
- self.block(vec![], TerminatorKind::Resume, true);
- }
-
fn tuple_like_shim<I>(&mut self, dest: Place<'tcx>, src: Place<'tcx>, tys: I)
where
I: Iterator<Item = Ty<'tcx>>,
diff --git a/compiler/rustc_trait_selection/src/traits/misc.rs b/compiler/rustc_trait_selection/src/traits/misc.rs
index cedd1aa54b876..fa8890fc35292 100644
--- a/compiler/rustc_trait_selection/src/traits/misc.rs
+++ b/compiler/rustc_trait_selection/src/traits/misc.rs
@@ -33,7 +33,8 @@ pub fn can_type_implement_copy(
| ty::Char
| ty::RawPtr(..)
| ty::Never
- | ty::Ref(_, _, hir::Mutability::Not) => return Ok(()),
+ | ty::Ref(_, _, hir::Mutability::Not)
+ | ty::Array(..) => return Ok(()),
ty::Adt(adt, substs) => (adt, substs),
diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs
index 481bfa4a26b36..2aa214694cb14 100644
--- a/compiler/rustc_trait_selection/src/traits/select/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs
@@ -1859,7 +1859,8 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
| ty::Char
| ty::RawPtr(..)
| ty::Never
- | ty::Ref(_, _, hir::Mutability::Not) => {
+ | ty::Ref(_, _, hir::Mutability::Not)
+ | ty::Array(..) => {
// Implementations provided in libcore
None
}
@@ -1872,11 +1873,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
| ty::Foreign(..)
| ty::Ref(_, _, hir::Mutability::Mut) => None,
- ty::Array(element_ty, _) => {
- // (*) binder moved here
- Where(obligation.predicate.rebind(vec![element_ty]))
- }
-
ty::Tuple(tys) => {
// (*) binder moved here
Where(obligation.predicate.rebind(tys.iter().map(|k| k.expect_ty()).collect()))
diff --git a/compiler/rustc_ty_utils/src/instance.rs b/compiler/rustc_ty_utils/src/instance.rs
index 87b729faa54e0..13ffb2a5adc86 100644
--- a/compiler/rustc_ty_utils/src/instance.rs
+++ b/compiler/rustc_ty_utils/src/instance.rs
@@ -362,7 +362,7 @@ fn resolve_associated_item<'tcx>(
let is_copy = self_ty.is_copy_modulo_regions(tcx.at(DUMMY_SP), param_env);
match self_ty.kind() {
_ if is_copy => (),
- ty::Array(..) | ty::Closure(..) | ty::Tuple(..) => {}
+ ty::Closure(..) | ty::Tuple(..) => {}
_ => return Ok(None),
};
diff --git a/library/core/src/array/mod.rs b/library/core/src/array/mod.rs
index 811850af3678d..089f1f3639062 100644
--- a/library/core/src/array/mod.rs
+++ b/library/core/src/array/mod.rs
@@ -330,6 +330,26 @@ impl<T: Ord, const N: usize> Ord for [T; N] {
}
}
+#[cfg(not(bootstrap))]
+#[stable(feature = "copy_clone_array_lib", since = "1.58.0")]
+impl<T: Copy, const N: usize> Copy for [T; N] {}
+
+#[cfg(not(bootstrap))]
+#[stable(feature = "copy_clone_array_lib", since = "1.58.0")]
+impl<T: Clone, const N: usize> Clone for [T; N] {
+ #[inline]
+ fn clone(&self) -> Self {
+ // SAFETY: we know for certain that this iterator will yield exactly `N`
+ // items.
+ unsafe { collect_into_array_unchecked(&mut self.iter().cloned()) }
+ }
+
+ #[inline]
+ fn clone_from(&mut self, other: &Self) {
+ self.clone_from_slice(other);
+ }
+}
+
// The Default impls cannot be done with const generics because `[T; 0]` doesn't
// require Default to be implemented, and having different impl blocks for
// different numbers isn't supported yet.
diff --git a/library/core/src/clone.rs b/library/core/src/clone.rs
index 281ff3badfbd8..6f9579043c37d 100644
--- a/library/core/src/clone.rs
+++ b/library/core/src/clone.rs
@@ -93,7 +93,6 @@
///
/// * Function item types (i.e., the distinct types defined for each function)
/// * Function pointer types (e.g., `fn() -> i32`)
-/// * Array types, for all sizes, if the item type also implements `Clone` (e.g., `[i32; 123456]`)
/// * Tuple types, if each component also implements `Clone` (e.g., `()`, `(i32, bool)`)
/// * Closure types, if they capture no value from the environment
/// or if all such captured values implement `Clone` themselves.
diff --git a/library/core/src/marker.rs b/library/core/src/marker.rs
index 37446bafacb24..71eea43aa54e1 100644
--- a/library/core/src/marker.rs
+++ b/library/core/src/marker.rs
@@ -359,7 +359,6 @@ pub trait StructuralEq {
///
/// * Function item types (i.e., the distinct types defined for each function)
/// * Function pointer types (e.g., `fn() -> i32`)
-/// * Array types, for all sizes, if the item type also implements `Copy` (e.g., `[i32; 123456]`)
/// * Tuple types, if each component also implements `Copy` (e.g., `()`, `(i32, bool)`)
/// * Closure types, if they capture no value from the environment
/// or if all such captured values implement `Copy` themselves.
diff --git a/src/test/ui/builtin-clone-unwind.rs b/src/test/ui/builtin-clone-unwind.rs
index 339bcfa1060a4..2caedb649a35a 100644
--- a/src/test/ui/builtin-clone-unwind.rs
+++ b/src/test/ui/builtin-clone-unwind.rs
@@ -53,7 +53,7 @@ fn main() {
].clone();
});
- assert!(result.is_err());
+ assert!(child.is_err());
assert_eq!(
1,
Rc::strong_count(&counter)
diff --git a/src/test/ui/chalkify/builtin-copy-clone.rs b/src/test/ui/chalkify/builtin-copy-clone.rs
index d403514b553b0..4323e87b08de7 100644
--- a/src/test/ui/chalkify/builtin-copy-clone.rs
+++ b/src/test/ui/chalkify/builtin-copy-clone.rs
@@ -23,11 +23,12 @@ fn test_copy_clone<T: Copy + Clone>(arg: T) {
fn foo() { }
fn main() {
+ // FIXME: add closures when they're considered WF
test_copy_clone(foo);
let f: fn() = foo;
test_copy_clone(f);
- // FIXME: add closures when they're considered WF
- test_copy_clone([1; 56]);
+ // FIXME(#86252): reinstate array test after chalk upgrade
+ //test_copy_clone([1; 56]);
test_copy_clone((1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1));
test_copy_clone((1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, true, 'a', 1.1));
test_copy_clone(());
diff --git a/src/test/ui/error-codes/E0206.rs b/src/test/ui/error-codes/E0206.rs
index bace046758112..0f3d427ce11ac 100644
--- a/src/test/ui/error-codes/E0206.rs
+++ b/src/test/ui/error-codes/E0206.rs
@@ -1,9 +1,3 @@
-type Foo = [u8; 256];
-
-impl Copy for Foo { }
-//~^ ERROR the trait `Copy` may not be implemented for this type
-//~| ERROR only traits defined in the current crate can be implemented for arbitrary types
-
#[derive(Copy, Clone)]
struct Bar;
diff --git a/src/test/ui/error-codes/E0206.stderr b/src/test/ui/error-codes/E0206.stderr
index e4ad4ffb45fee..57ae2647d339c 100644
--- a/src/test/ui/error-codes/E0206.stderr
+++ b/src/test/ui/error-codes/E0206.stderr
@@ -1,27 +1,9 @@
error[E0206]: the trait `Copy` may not be implemented for this type
- --> $DIR/E0206.rs:3:15
- |
-LL | impl Copy for Foo { }
- | ^^^ type is not a structure or enumeration
-
-error[E0206]: the trait `Copy` may not be implemented for this type
- --> $DIR/E0206.rs:10:15
+ --> $DIR/E0206.rs:4:15
|
LL | impl Copy for &'static mut Bar { }
| ^^^^^^^^^^^^^^^^ type is not a structure or enumeration
-error[E0117]: only traits defined in the current crate can be implemented for arbitrary types
- --> $DIR/E0206.rs:3:1
- |
-LL | impl Copy for Foo { }
- | ^^^^^^^^^^^^^^---
- | | |
- | | this is not defined in the current crate because arrays are always foreign
- | impl doesn't use only types from inside the current crate
- |
- = note: define and implement a trait or new type instead
-
-error: aborting due to 3 previous errors
+error: aborting due to previous error
-Some errors have detailed explanations: E0117, E0206.
-For more information about an error, try `rustc --explain E0117`.
+For more information about this error, try `rustc --explain E0206`.