diff options
21 files changed, 254 insertions, 11 deletions
diff --git a/compiler/rustc_hir/src/lang_items.rs b/compiler/rustc_hir/src/lang_items.rs index 2e099a97b65..311cf8f995c 100644 --- a/compiler/rustc_hir/src/lang_items.rs +++ b/compiler/rustc_hir/src/lang_items.rs @@ -440,6 +440,7 @@ language_item_table! { // Reborrowing related lang-items Reborrow, sym::reborrow, reborrow, Target::Trait, GenericRequirement::Exact(0); + CoerceShared, sym::coerce_shared, coerce_shared, Target::Trait, GenericRequirement::Exact(0); } /// The requirement imposed on the generics of a lang item diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs index cd422da0c1c..63b0de377c9 100644 --- a/compiler/rustc_span/src/symbol.rs +++ b/compiler/rustc_span/src/symbol.rs @@ -679,6 +679,7 @@ symbols! { cmpxchg16b_target_feature, cmse_nonsecure_entry, coerce_pointee_validated, + coerce_shared, coerce_unsized, cold, cold_path, diff --git a/library/core/src/marker.rs b/library/core/src/marker.rs index 1c100312a9a..4b767d8d622 100644 --- a/library/core/src/marker.rs +++ b/library/core/src/marker.rs @@ -1341,11 +1341,3 @@ pub macro CoercePointee($item:item) { pub trait CoercePointeeValidated { /* compiler built-in */ } - -/// Allows value to be reborrowed as exclusive, creating a copy of the value -/// that disables the source for reads and writes for the lifetime of the copy. -#[lang = "reborrow"] -#[unstable(feature = "reborrow", issue = "145612")] -pub trait Reborrow { - // Empty. -} diff --git a/library/core/src/ops/mod.rs b/library/core/src/ops/mod.rs index 87dd873fdb5..ab1ad407ee2 100644 --- a/library/core/src/ops/mod.rs +++ b/library/core/src/ops/mod.rs @@ -149,6 +149,7 @@ mod function; mod index; mod index_range; mod range; +mod reborrow; mod try_trait; mod unsize; @@ -189,6 +190,8 @@ pub use self::range::{Bound, RangeBounds, RangeInclusive, RangeToInclusive}; pub use self::range::{OneSidedRange, OneSidedRangeBound}; #[stable(feature = "rust1", since = "1.0.0")] pub use self::range::{Range, RangeFrom, RangeFull, RangeTo}; +#[unstable(feature = "reborrow", issue = "145612")] +pub use self::reborrow::{CoerceShared, Reborrow}; #[unstable(feature = "try_trait_v2_residual", issue = "91285")] pub use self::try_trait::Residual; #[unstable(feature = "try_trait_v2_yeet", issue = "96374")] diff --git a/library/core/src/ops/reborrow.rs b/library/core/src/ops/reborrow.rs new file mode 100644 index 00000000000..f83f4233a4d --- /dev/null +++ b/library/core/src/ops/reborrow.rs @@ -0,0 +1,16 @@ +/// Allows value to be reborrowed as exclusive, creating a copy of the value +/// that disables the source for reads and writes for the lifetime of the copy. +#[lang = "reborrow"] +#[unstable(feature = "reborrow", issue = "145612")] +pub trait Reborrow { + // Empty. +} + +/// Allows reborrowable value to be reborrowed as shared, creating a copy +/// that disables the source for writes for the lifetime of the copy. +#[lang = "coerce_shared"] +#[unstable(feature = "reborrow", issue = "145612")] +pub trait CoerceShared: Reborrow { + /// The type of this value when reborrowed as shared. + type Target: Copy; +} diff --git a/tests/ui/feature-gates/feature-gate-reborrow-coerce-shared.rs b/tests/ui/feature-gates/feature-gate-reborrow-coerce-shared.rs new file mode 100644 index 00000000000..c8ca4537089 --- /dev/null +++ b/tests/ui/feature-gates/feature-gate-reborrow-coerce-shared.rs @@ -0,0 +1,3 @@ +use std::ops::CoerceShared; //~ ERROR use of unstable library feature `reborrow` + +fn main() {} diff --git a/tests/ui/feature-gates/feature-gate-reborrow-coerce-shared.stderr b/tests/ui/feature-gates/feature-gate-reborrow-coerce-shared.stderr new file mode 100644 index 00000000000..dbbbcdf2fd5 --- /dev/null +++ b/tests/ui/feature-gates/feature-gate-reborrow-coerce-shared.stderr @@ -0,0 +1,13 @@ +error[E0658]: use of unstable library feature `reborrow` + --> $DIR/feature-gate-reborrow-coerce-shared.rs:1:5 + | +LL | use std::ops::CoerceShared; + | ^^^^^^^^^^^^^^^^^^^^^^ + | + = note: see issue #145612 <https://github.com/rust-lang/rust/issues/145612> for more information + = help: add `#![feature(reborrow)]` to the crate attributes to enable + = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date + +error: aborting due to 1 previous error + +For more information about this error, try `rustc --explain E0658`. diff --git a/tests/ui/feature-gates/feature-gate-reborrow.rs b/tests/ui/feature-gates/feature-gate-reborrow.rs index f016f6c6bfa..96eecfb28a1 100644 --- a/tests/ui/feature-gates/feature-gate-reborrow.rs +++ b/tests/ui/feature-gates/feature-gate-reborrow.rs @@ -1,3 +1,3 @@ -use std::marker::Reborrow; //~ ERROR use of unstable library feature `reborrow` +use std::ops::Reborrow; //~ ERROR use of unstable library feature `reborrow` fn main() {} diff --git a/tests/ui/feature-gates/feature-gate-reborrow.stderr b/tests/ui/feature-gates/feature-gate-reborrow.stderr index 5e3033f3bf1..1224909f564 100644 --- a/tests/ui/feature-gates/feature-gate-reborrow.stderr +++ b/tests/ui/feature-gates/feature-gate-reborrow.stderr @@ -1,8 +1,8 @@ error[E0658]: use of unstable library feature `reborrow` --> $DIR/feature-gate-reborrow.rs:1:5 | -LL | use std::marker::Reborrow; - | ^^^^^^^^^^^^^^^^^^^^^ +LL | use std::ops::Reborrow; + | ^^^^^^^^^^^^^^^^^^ | = note: see issue #145612 <https://github.com/rust-lang/rust/issues/145612> for more information = help: add `#![feature(reborrow)]` to the crate attributes to enable diff --git a/tests/ui/reborrow/custom_mut.rs b/tests/ui/reborrow/custom_mut.rs new file mode 100644 index 00000000000..1e7c4693238 --- /dev/null +++ b/tests/ui/reborrow/custom_mut.rs @@ -0,0 +1,13 @@ +#![feature(reborrow)] +use std::ops::Reborrow; + +struct CustomMut<'a, T>(&'a mut T); +impl<'a, T> Reborrow for CustomMut<'a, T> {} + +fn method(a: CustomMut<'_, ()>) {} + +fn main() { + let a = CustomMut(&mut ()); + let _ = method(a); + let _ = method(a); //~ERROR use of moved value: `a` +} diff --git a/tests/ui/reborrow/custom_mut.stderr b/tests/ui/reborrow/custom_mut.stderr new file mode 100644 index 00000000000..3b3f47b62d6 --- /dev/null +++ b/tests/ui/reborrow/custom_mut.stderr @@ -0,0 +1,29 @@ +error[E0382]: use of moved value: `a` + --> $DIR/custom_mut.rs:12:20 + | +LL | let a = CustomMut(&mut ()); + | - move occurs because `a` has type `CustomMut<'_, ()>`, which does not implement the `Copy` trait +LL | let _ = method(a); + | - value moved here +LL | let _ = method(a); + | ^ value used here after move + | +note: consider changing this parameter type in function `method` to borrow instead if owning the value isn't necessary + --> $DIR/custom_mut.rs:7:14 + | +LL | fn method(a: CustomMut<'_, ()>) {} + | ------ ^^^^^^^^^^^^^^^^^ this parameter takes ownership of the value + | | + | in this function +note: if `CustomMut<'_, ()>` implemented `Clone`, you could clone the value + --> $DIR/custom_mut.rs:4:1 + | +LL | struct CustomMut<'a, T>(&'a mut T); + | ^^^^^^^^^^^^^^^^^^^^^^^ consider implementing `Clone` for this type +... +LL | let _ = method(a); + | - you could clone this value + +error: aborting due to 1 previous error + +For more information about this error, try `rustc --explain E0382`. diff --git a/tests/ui/reborrow/custom_mut_coerce_shared.rs b/tests/ui/reborrow/custom_mut_coerce_shared.rs new file mode 100644 index 00000000000..e2d25835c09 --- /dev/null +++ b/tests/ui/reborrow/custom_mut_coerce_shared.rs @@ -0,0 +1,28 @@ +#![feature(reborrow)] +use std::ops::{CoerceShared, Reborrow}; + +struct CustomMut<'a, T>(&'a mut T); +impl<'a, T> Reborrow for CustomMut<'a, T> {} +impl<'a, T> CoerceShared for CustomMut<'a, T> { + type Target = CustomRef<'a, T>; +} + +struct CustomRef<'a, T>(&'a T); + +impl<'a, T> Clone for CustomRef<'a, T> { + fn clone(&self) -> Self { + Self(self.0) + } +} +impl<'a, T> Copy for CustomRef<'a, T> {} + +fn method(a: CustomRef<'_, ()>) {} //~NOTE function defined here + +fn main() { + let a = CustomMut(&mut ()); + method(a); + //~^ ERROR mismatched types + //~| NOTE expected `CustomRef<'_, ()>`, found `CustomMut<'_, ()>` + //~| NOTE arguments to this function are incorrect + //~| NOTE expected struct `CustomRef<'_, ()>` +} diff --git a/tests/ui/reborrow/custom_mut_coerce_shared.stderr b/tests/ui/reborrow/custom_mut_coerce_shared.stderr new file mode 100644 index 00000000000..508651badc0 --- /dev/null +++ b/tests/ui/reborrow/custom_mut_coerce_shared.stderr @@ -0,0 +1,19 @@ +error[E0308]: mismatched types + --> $DIR/custom_mut_coerce_shared.rs:23:12 + | +LL | method(a); + | ------ ^ expected `CustomRef<'_, ()>`, found `CustomMut<'_, ()>` + | | + | arguments to this function are incorrect + | + = note: expected struct `CustomRef<'_, ()>` + found struct `CustomMut<'_, ()>` +note: function defined here + --> $DIR/custom_mut_coerce_shared.rs:19:4 + | +LL | fn method(a: CustomRef<'_, ()>) {} + | ^^^^^^ -------------------- + +error: aborting due to 1 previous error + +For more information about this error, try `rustc --explain E0308`. diff --git a/tests/ui/reborrow/option_mut.rs b/tests/ui/reborrow/option_mut.rs new file mode 100644 index 00000000000..04d8301772d --- /dev/null +++ b/tests/ui/reborrow/option_mut.rs @@ -0,0 +1,7 @@ +fn method(a: Option<&mut ()>) {} + +fn main() { + let a = Some(&mut ()); + let _ = method(a); + let _ = method(a); //~ERROR use of moved value: `a` +} diff --git a/tests/ui/reborrow/option_mut.stderr b/tests/ui/reborrow/option_mut.stderr new file mode 100644 index 00000000000..d665e266079 --- /dev/null +++ b/tests/ui/reborrow/option_mut.stderr @@ -0,0 +1,21 @@ +error[E0382]: use of moved value: `a` + --> $DIR/option_mut.rs:6:20 + | +LL | let a = Some(&mut ()); + | - move occurs because `a` has type `Option<&mut ()>`, which does not implement the `Copy` trait +LL | let _ = method(a); + | - value moved here +LL | let _ = method(a); + | ^ value used here after move + | +note: consider changing this parameter type in function `method` to borrow instead if owning the value isn't necessary + --> $DIR/option_mut.rs:1:14 + | +LL | fn method(a: Option<&mut ()>) {} + | ------ ^^^^^^^^^^^^^^^ this parameter takes ownership of the value + | | + | in this function + +error: aborting due to 1 previous error + +For more information about this error, try `rustc --explain E0382`. diff --git a/tests/ui/reborrow/option_mut_coerce_shared.rs b/tests/ui/reborrow/option_mut_coerce_shared.rs new file mode 100644 index 00000000000..95d33ed94dd --- /dev/null +++ b/tests/ui/reborrow/option_mut_coerce_shared.rs @@ -0,0 +1,11 @@ +fn method(a: Option<&()>) {} //~NOTE function defined here + +fn main() { + let a = Some(&mut ()); + method(a); + //~^ ERROR mismatched types + //~| NOTE arguments to this function are incorrect + //~| NOTE types differ in mutability + //~| NOTE expected enum `Option<&()>` + //~| NOTE found enum `Option<&mut ()>` +} diff --git a/tests/ui/reborrow/option_mut_coerce_shared.stderr b/tests/ui/reborrow/option_mut_coerce_shared.stderr new file mode 100644 index 00000000000..6ca1a237461 --- /dev/null +++ b/tests/ui/reborrow/option_mut_coerce_shared.stderr @@ -0,0 +1,23 @@ +error[E0308]: mismatched types + --> $DIR/option_mut_coerce_shared.rs:5:12 + | +LL | method(a); + | ------ ^ types differ in mutability + | | + | arguments to this function are incorrect + | + = note: expected enum `Option<&()>` + found enum `Option<&mut ()>` +note: function defined here + --> $DIR/option_mut_coerce_shared.rs:1:4 + | +LL | fn method(a: Option<&()>) {} + | ^^^^^^ -------------- +help: try using `.as_deref()` to convert `Option<&mut ()>` to `Option<&()>` + | +LL | method(a.as_deref()); + | +++++++++++ + +error: aborting due to 1 previous error + +For more information about this error, try `rustc --explain E0308`. diff --git a/tests/ui/reborrow/pin_mut.rs b/tests/ui/reborrow/pin_mut.rs new file mode 100644 index 00000000000..959cb14f8c9 --- /dev/null +++ b/tests/ui/reborrow/pin_mut.rs @@ -0,0 +1,10 @@ +use std::pin::Pin; + +fn method(a: Pin<&mut ()>) {} + +fn main() { + let a = &mut (); + let a = Pin::new(a); + let _ = method(a); + let _ = method(a); //~ERROR use of moved value: `a` +} diff --git a/tests/ui/reborrow/pin_mut.stderr b/tests/ui/reborrow/pin_mut.stderr new file mode 100644 index 00000000000..64e3f603e11 --- /dev/null +++ b/tests/ui/reborrow/pin_mut.stderr @@ -0,0 +1,21 @@ +error[E0382]: use of moved value: `a` + --> $DIR/pin_mut.rs:9:20 + | +LL | let a = Pin::new(a); + | - move occurs because `a` has type `Pin<&mut ()>`, which does not implement the `Copy` trait +LL | let _ = method(a); + | - value moved here +LL | let _ = method(a); + | ^ value used here after move + | +note: consider changing this parameter type in function `method` to borrow instead if owning the value isn't necessary + --> $DIR/pin_mut.rs:3:14 + | +LL | fn method(a: Pin<&mut ()>) {} + | ------ ^^^^^^^^^^^^ this parameter takes ownership of the value + | | + | in this function + +error: aborting due to 1 previous error + +For more information about this error, try `rustc --explain E0382`. diff --git a/tests/ui/reborrow/pin_mut_coerce_shared.rs b/tests/ui/reborrow/pin_mut_coerce_shared.rs new file mode 100644 index 00000000000..06af0b765d0 --- /dev/null +++ b/tests/ui/reborrow/pin_mut_coerce_shared.rs @@ -0,0 +1,13 @@ +use std::pin::Pin; + +fn method(a: Pin<&()>) {} //~NOTE function defined here + +fn main() { + let a = &mut (); + let a = Pin::new(a); + method(a); + //~^ ERROR mismatched types + //~| NOTE arguments to this function are incorrect + //~| NOTE types differ in mutability + //~| NOTE expected struct `Pin<&()>` +} diff --git a/tests/ui/reborrow/pin_mut_coerce_shared.stderr b/tests/ui/reborrow/pin_mut_coerce_shared.stderr new file mode 100644 index 00000000000..74ecf4de4c7 --- /dev/null +++ b/tests/ui/reborrow/pin_mut_coerce_shared.stderr @@ -0,0 +1,19 @@ +error[E0308]: mismatched types + --> $DIR/pin_mut_coerce_shared.rs:8:12 + | +LL | method(a); + | ------ ^ types differ in mutability + | | + | arguments to this function are incorrect + | + = note: expected struct `Pin<&()>` + found struct `Pin<&mut ()>` +note: function defined here + --> $DIR/pin_mut_coerce_shared.rs:3:4 + | +LL | fn method(a: Pin<&()>) {} + | ^^^^^^ ----------- + +error: aborting due to 1 previous error + +For more information about this error, try `rustc --explain E0308`. |