From 8d64937dc25eb2b01596a3581ec2660d8e81b9b2 Mon Sep 17 00:00:00 2001 From: David Wood Date: Wed, 16 Jul 2025 10:56:32 +0000 Subject: [PATCH] trait_sel: `MetaSized` always holds temporarily As a temporary measure while a proper fix for `tests/ui/sized-hierarchy/incomplete-inference-issue-143992.rs` is implemented, make `MetaSized` obligations always hold. In effect, temporarily reverting the `sized_hierarchy` feature. This is a small change that can be backported. --- .../rustc_trait_selection/src/traits/util.rs | 7 +++ ...st-size_of_val-align_of_val-extern-type.rs | 4 +- ...ize_of_val-align_of_val-extern-type.stderr | 38 +++----------- tests/ui/extern/extern-types-size_of_val.rs | 4 +- .../ui/extern/extern-types-size_of_val.stderr | 39 -------------- tests/ui/extern/extern-types-unsized.rs | 2 - tests/ui/extern/extern-types-unsized.stderr | 30 +---------- tests/ui/extern/unsized-extern-derefmove.rs | 4 -- .../ui/extern/unsized-extern-derefmove.stderr | 52 +------------------ .../layout/unconstrained-param-ice-137308.rs | 1 - .../unconstrained-param-ice-137308.stderr | 11 +--- tests/ui/nll/issue-50716.rs | 2 +- tests/ui/nll/issue-50716.stderr | 18 +------ ...omplete-inference-issue-143992.next.stderr | 17 ++++++ .../incomplete-inference-issue-143992.rs | 29 +++++++++++ .../sized-hierarchy/overflow.current.stderr | 45 ---------------- tests/ui/sized-hierarchy/overflow.rs | 6 ++- .../resolve-impl-before-constrain-check.rs | 1 - ...resolve-impl-before-constrain-check.stderr | 11 +--- 19 files changed, 77 insertions(+), 244 deletions(-) delete mode 100644 tests/ui/extern/extern-types-size_of_val.stderr create mode 100644 tests/ui/sized-hierarchy/incomplete-inference-issue-143992.next.stderr create mode 100644 tests/ui/sized-hierarchy/incomplete-inference-issue-143992.rs delete mode 100644 tests/ui/sized-hierarchy/overflow.current.stderr diff --git a/compiler/rustc_trait_selection/src/traits/util.rs b/compiler/rustc_trait_selection/src/traits/util.rs index 141454bfe3754..00e31021eec0d 100644 --- a/compiler/rustc_trait_selection/src/traits/util.rs +++ b/compiler/rustc_trait_selection/src/traits/util.rs @@ -378,6 +378,13 @@ pub fn sizedness_fast_path<'tcx>(tcx: TyCtxt<'tcx>, predicate: ty::Predicate<'tc _ => return false, }; + // FIXME(sized_hierarchy): this temporarily reverts the `sized_hierarchy` feature + // while a proper fix for `tests/ui/sized-hierarchy/incomplete-inference-issue-143992.rs` + // is pending a proper fix + if !tcx.features().sized_hierarchy() && matches!(sizedness, SizedTraitKind::MetaSized) { + return true; + } + if trait_pred.self_ty().has_trivial_sizedness(tcx, sizedness) { debug!("fast path -- trivial sizedness"); return true; diff --git a/tests/ui/consts/const-size_of_val-align_of_val-extern-type.rs b/tests/ui/consts/const-size_of_val-align_of_val-extern-type.rs index 2372d1c3e3d7e..fd3ed8f18265e 100644 --- a/tests/ui/consts/const-size_of_val-align_of_val-extern-type.rs +++ b/tests/ui/consts/const-size_of_val-align_of_val-extern-type.rs @@ -8,8 +8,8 @@ extern "C" { } const _SIZE: usize = unsafe { size_of_val(&4 as *const i32 as *const Opaque) }; -//~^ ERROR the size for values of type `Opaque` cannot be known +//~^ ERROR `extern type` does not have known layout const _ALIGN: usize = unsafe { align_of_val(&4 as *const i32 as *const Opaque) }; -//~^ ERROR the size for values of type `Opaque` cannot be known +//~^ ERROR `extern type` does not have known layout fn main() {} diff --git a/tests/ui/consts/const-size_of_val-align_of_val-extern-type.stderr b/tests/ui/consts/const-size_of_val-align_of_val-extern-type.stderr index 825b9e941584c..23f7aaf538edc 100644 --- a/tests/ui/consts/const-size_of_val-align_of_val-extern-type.stderr +++ b/tests/ui/consts/const-size_of_val-align_of_val-extern-type.stderr @@ -1,39 +1,15 @@ -error[E0277]: the size for values of type `Opaque` cannot be known - --> $DIR/const-size_of_val-align_of_val-extern-type.rs:10:43 +error[E0080]: `extern type` does not have known layout + --> $DIR/const-size_of_val-align_of_val-extern-type.rs:10:31 | LL | const _SIZE: usize = unsafe { size_of_val(&4 as *const i32 as *const Opaque) }; - | ----------- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `MetaSized` is not implemented for `Opaque` - | | - | required by a bound introduced by this call - | - = note: the trait bound `Opaque: MetaSized` is not satisfied -note: required by a bound in `std::intrinsics::size_of_val` - --> $SRC_DIR/core/src/intrinsics/mod.rs:LL:COL -help: consider borrowing here - | -LL | const _SIZE: usize = unsafe { size_of_val(&(&4 as *const i32 as *const Opaque)) }; - | ++ + -LL | const _SIZE: usize = unsafe { size_of_val(&mut (&4 as *const i32 as *const Opaque)) }; - | ++++++ + + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ evaluation of `_SIZE` failed here -error[E0277]: the size for values of type `Opaque` cannot be known - --> $DIR/const-size_of_val-align_of_val-extern-type.rs:12:45 +error[E0080]: `extern type` does not have known layout + --> $DIR/const-size_of_val-align_of_val-extern-type.rs:12:32 | LL | const _ALIGN: usize = unsafe { align_of_val(&4 as *const i32 as *const Opaque) }; - | ------------ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `MetaSized` is not implemented for `Opaque` - | | - | required by a bound introduced by this call - | - = note: the trait bound `Opaque: MetaSized` is not satisfied -note: required by a bound in `std::intrinsics::align_of_val` - --> $SRC_DIR/core/src/intrinsics/mod.rs:LL:COL -help: consider borrowing here - | -LL | const _ALIGN: usize = unsafe { align_of_val(&(&4 as *const i32 as *const Opaque)) }; - | ++ + -LL | const _ALIGN: usize = unsafe { align_of_val(&mut (&4 as *const i32 as *const Opaque)) }; - | ++++++ + + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ evaluation of `_ALIGN` failed here error: aborting due to 2 previous errors -For more information about this error, try `rustc --explain E0277`. +For more information about this error, try `rustc --explain E0080`. diff --git a/tests/ui/extern/extern-types-size_of_val.rs b/tests/ui/extern/extern-types-size_of_val.rs index 3ff51b9b6b0df..875ae9a535a7a 100644 --- a/tests/ui/extern/extern-types-size_of_val.rs +++ b/tests/ui/extern/extern-types-size_of_val.rs @@ -1,4 +1,4 @@ -//@ check-fail +//@ check-pass #![feature(extern_types)] use std::mem::{align_of_val, size_of_val}; @@ -11,7 +11,5 @@ fn main() { let x: &A = unsafe { &*(1usize as *const A) }; size_of_val(x); - //~^ ERROR the size for values of type `A` cannot be known align_of_val(x); - //~^ ERROR the size for values of type `A` cannot be known } diff --git a/tests/ui/extern/extern-types-size_of_val.stderr b/tests/ui/extern/extern-types-size_of_val.stderr deleted file mode 100644 index 8678c6c3d6036..0000000000000 --- a/tests/ui/extern/extern-types-size_of_val.stderr +++ /dev/null @@ -1,39 +0,0 @@ -error[E0277]: the size for values of type `A` cannot be known - --> $DIR/extern-types-size_of_val.rs:13:17 - | -LL | size_of_val(x); - | ----------- ^ the trait `MetaSized` is not implemented for `A` - | | - | required by a bound introduced by this call - | - = note: the trait bound `A: MetaSized` is not satisfied -note: required by a bound in `std::mem::size_of_val` - --> $SRC_DIR/core/src/mem/mod.rs:LL:COL -help: consider borrowing here - | -LL | size_of_val(&x); - | + -LL | size_of_val(&mut x); - | ++++ - -error[E0277]: the size for values of type `A` cannot be known - --> $DIR/extern-types-size_of_val.rs:15:18 - | -LL | align_of_val(x); - | ------------ ^ the trait `MetaSized` is not implemented for `A` - | | - | required by a bound introduced by this call - | - = note: the trait bound `A: MetaSized` is not satisfied -note: required by a bound in `std::mem::align_of_val` - --> $SRC_DIR/core/src/mem/mod.rs:LL:COL -help: consider borrowing here - | -LL | align_of_val(&x); - | + -LL | align_of_val(&mut x); - | ++++ - -error: aborting due to 2 previous errors - -For more information about this error, try `rustc --explain E0277`. diff --git a/tests/ui/extern/extern-types-unsized.rs b/tests/ui/extern/extern-types-unsized.rs index 46cdc24e08328..94a222a7e7e01 100644 --- a/tests/ui/extern/extern-types-unsized.rs +++ b/tests/ui/extern/extern-types-unsized.rs @@ -27,9 +27,7 @@ fn main() { assert_sized::>(); //~^ ERROR the size for values of type - //~| ERROR the size for values of type assert_sized::>>(); //~^ ERROR the size for values of type - //~| ERROR the size for values of type } diff --git a/tests/ui/extern/extern-types-unsized.stderr b/tests/ui/extern/extern-types-unsized.stderr index 43dd9800d6d30..a587d4dda55c8 100644 --- a/tests/ui/extern/extern-types-unsized.stderr +++ b/tests/ui/extern/extern-types-unsized.stderr @@ -59,21 +59,8 @@ help: consider relaxing the implicit `Sized` restriction LL | fn assert_sized() {} | ++++++++ -error[E0277]: the size for values of type `A` cannot be known - --> $DIR/extern-types-unsized.rs:28:20 - | -LL | assert_sized::>(); - | ^^^^^^ doesn't have a known size - | - = help: the trait `MetaSized` is not implemented for `A` -note: required by a bound in `Bar` - --> $DIR/extern-types-unsized.rs:14:12 - | -LL | struct Bar { - | ^ required by this bound in `Bar` - error[E0277]: the size for values of type `A` cannot be known at compilation time - --> $DIR/extern-types-unsized.rs:32:20 + --> $DIR/extern-types-unsized.rs:31:20 | LL | assert_sized::>>(); | ^^^^^^^^^^^ doesn't have a size known at compile-time @@ -94,19 +81,6 @@ help: consider relaxing the implicit `Sized` restriction LL | fn assert_sized() {} | ++++++++ -error[E0277]: the size for values of type `A` cannot be known - --> $DIR/extern-types-unsized.rs:32:20 - | -LL | assert_sized::>>(); - | ^^^^^^^^^^^ doesn't have a known size - | - = help: the trait `MetaSized` is not implemented for `A` -note: required by a bound in `Bar` - --> $DIR/extern-types-unsized.rs:14:12 - | -LL | struct Bar { - | ^ required by this bound in `Bar` - -error: aborting due to 6 previous errors +error: aborting due to 4 previous errors For more information about this error, try `rustc --explain E0277`. diff --git a/tests/ui/extern/unsized-extern-derefmove.rs b/tests/ui/extern/unsized-extern-derefmove.rs index c02375266ab47..39597a12fe117 100644 --- a/tests/ui/extern/unsized-extern-derefmove.rs +++ b/tests/ui/extern/unsized-extern-derefmove.rs @@ -7,14 +7,10 @@ extern "C" { } unsafe fn make_device() -> Box { -//~^ ERROR the size for values of type `Device` cannot be known Box::from_raw(0 as *mut _) -//~^ ERROR the size for values of type `Device` cannot be known -//~| ERROR the size for values of type `Device` cannot be known } fn main() { let d: Device = unsafe { *make_device() }; //~^ ERROR the size for values of type `Device` cannot be known -//~| ERROR the size for values of type `Device` cannot be known } diff --git a/tests/ui/extern/unsized-extern-derefmove.stderr b/tests/ui/extern/unsized-extern-derefmove.stderr index a9efc2e66e3b0..c43184d94e177 100644 --- a/tests/ui/extern/unsized-extern-derefmove.stderr +++ b/tests/ui/extern/unsized-extern-derefmove.stderr @@ -1,43 +1,5 @@ -error[E0277]: the size for values of type `Device` cannot be known - --> $DIR/unsized-extern-derefmove.rs:9:28 - | -LL | unsafe fn make_device() -> Box { - | ^^^^^^^^^^^ doesn't have a known size - | - = help: the trait `MetaSized` is not implemented for `Device` -note: required by a bound in `Box` - --> $SRC_DIR/alloc/src/boxed.rs:LL:COL - -error[E0277]: the size for values of type `Device` cannot be known - --> $DIR/unsized-extern-derefmove.rs:11:19 - | -LL | Box::from_raw(0 as *mut _) - | ------------- ^^^^^^^^^^^ the trait `MetaSized` is not implemented for `Device` - | | - | required by a bound introduced by this call - | - = note: the trait bound `Device: MetaSized` is not satisfied -note: required by a bound in `Box::::from_raw` - --> $SRC_DIR/alloc/src/boxed.rs:LL:COL -help: consider borrowing here - | -LL | Box::from_raw(&(0 as *mut _)) - | ++ + -LL | Box::from_raw(&mut (0 as *mut _)) - | ++++++ + - -error[E0277]: the size for values of type `Device` cannot be known - --> $DIR/unsized-extern-derefmove.rs:11:5 - | -LL | Box::from_raw(0 as *mut _) - | ^^^^^^^^^^^^^^^^^^^^^^^^^^ doesn't have a known size - | - = help: the trait `MetaSized` is not implemented for `Device` -note: required by a bound in `Box` - --> $SRC_DIR/alloc/src/boxed.rs:LL:COL - error[E0277]: the size for values of type `Device` cannot be known at compilation time - --> $DIR/unsized-extern-derefmove.rs:17:9 + --> $DIR/unsized-extern-derefmove.rs:14:9 | LL | let d: Device = unsafe { *make_device() }; | ^ doesn't have a size known at compile-time @@ -49,16 +11,6 @@ help: consider borrowing here LL | let d: &Device = unsafe { *make_device() }; | + -error[E0277]: the size for values of type `Device` cannot be known - --> $DIR/unsized-extern-derefmove.rs:17:31 - | -LL | let d: Device = unsafe { *make_device() }; - | ^^^^^^^^^^^^^ doesn't have a known size - | - = help: the trait `MetaSized` is not implemented for `Device` -note: required by a bound in `Box` - --> $SRC_DIR/alloc/src/boxed.rs:LL:COL - -error: aborting due to 5 previous errors +error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0277`. diff --git a/tests/ui/layout/unconstrained-param-ice-137308.rs b/tests/ui/layout/unconstrained-param-ice-137308.rs index 03b7e7599601a..d05e6e1fd3f33 100644 --- a/tests/ui/layout/unconstrained-param-ice-137308.rs +++ b/tests/ui/layout/unconstrained-param-ice-137308.rs @@ -17,4 +17,3 @@ impl A for u8 { //~ ERROR: the type parameter `C` is not constrained #[rustc_layout(debug)] struct S([u8; ::B]); //~^ ERROR: the type has an unknown layout -//~| ERROR: type annotations needed diff --git a/tests/ui/layout/unconstrained-param-ice-137308.stderr b/tests/ui/layout/unconstrained-param-ice-137308.stderr index 82cd1217c4903..615c131eb9045 100644 --- a/tests/ui/layout/unconstrained-param-ice-137308.stderr +++ b/tests/ui/layout/unconstrained-param-ice-137308.stderr @@ -4,19 +4,12 @@ error[E0207]: the type parameter `C` is not constrained by the impl trait, self LL | impl A for u8 { | ^ unconstrained type parameter -error[E0282]: type annotations needed - --> $DIR/unconstrained-param-ice-137308.rs:18:16 - | -LL | struct S([u8; ::B]); - | ^^ cannot infer type for type parameter `C` - error: the type has an unknown layout --> $DIR/unconstrained-param-ice-137308.rs:18:1 | LL | struct S([u8; ::B]); | ^^^^^^^^ -error: aborting due to 3 previous errors +error: aborting due to 2 previous errors -Some errors have detailed explanations: E0207, E0282. -For more information about an error, try `rustc --explain E0207`. +For more information about this error, try `rustc --explain E0207`. diff --git a/tests/ui/nll/issue-50716.rs b/tests/ui/nll/issue-50716.rs index 76c6fc5e7b925..96168ebeaa165 100644 --- a/tests/ui/nll/issue-50716.rs +++ b/tests/ui/nll/issue-50716.rs @@ -5,7 +5,7 @@ trait A { type X: ?Sized; } -fn foo<'a, T: 'static>(s: Box<<&'a T as A>::X>) //~ ERROR +fn foo<'a, T: 'static>(s: Box<<&'a T as A>::X>) where for<'b> &'b T: A, <&'static T as A>::X: Sized diff --git a/tests/ui/nll/issue-50716.stderr b/tests/ui/nll/issue-50716.stderr index edd7fd765dade..536f88085ded3 100644 --- a/tests/ui/nll/issue-50716.stderr +++ b/tests/ui/nll/issue-50716.stderr @@ -1,18 +1,3 @@ -error[E0308]: mismatched types - --> $DIR/issue-50716.rs:8:27 - | -LL | fn foo<'a, T: 'static>(s: Box<<&'a T as A>::X>) - | ^^^^^^^^^^^^^^^^^^^^ lifetime mismatch - | - = note: expected trait `<<&'a T as A>::X as MetaSized>` - found trait `<<&'static T as A>::X as MetaSized>` -note: the lifetime `'a` as defined here... - --> $DIR/issue-50716.rs:8:8 - | -LL | fn foo<'a, T: 'static>(s: Box<<&'a T as A>::X>) - | ^^ - = note: ...does not necessarily outlive the static lifetime - error: lifetime may not live long enough --> $DIR/issue-50716.rs:13:14 | @@ -22,6 +7,5 @@ LL | fn foo<'a, T: 'static>(s: Box<<&'a T as A>::X>) LL | let _x = *s; | ^^ proving this value is `Sized` requires that `'a` must outlive `'static` -error: aborting due to 2 previous errors +error: aborting due to 1 previous error -For more information about this error, try `rustc --explain E0308`. diff --git a/tests/ui/sized-hierarchy/incomplete-inference-issue-143992.next.stderr b/tests/ui/sized-hierarchy/incomplete-inference-issue-143992.next.stderr new file mode 100644 index 0000000000000..cf56f42afc8a3 --- /dev/null +++ b/tests/ui/sized-hierarchy/incomplete-inference-issue-143992.next.stderr @@ -0,0 +1,17 @@ +error[E0308]: mismatched types + --> $DIR/incomplete-inference-issue-143992.rs:27:28 + | +LL | let _x = T::Assoc::new(()); + | ------------- ^^ expected `[u32; 1]`, found `()` + | | + | arguments to this function are incorrect + | +note: associated function defined here + --> $DIR/incomplete-inference-issue-143992.rs:18:8 + | +LL | fn new(r: R) -> R { + | ^^^ ---- + +error: aborting due to 1 previous error + +For more information about this error, try `rustc --explain E0308`. diff --git a/tests/ui/sized-hierarchy/incomplete-inference-issue-143992.rs b/tests/ui/sized-hierarchy/incomplete-inference-issue-143992.rs new file mode 100644 index 0000000000000..3e3e1dc50e58b --- /dev/null +++ b/tests/ui/sized-hierarchy/incomplete-inference-issue-143992.rs @@ -0,0 +1,29 @@ +//@ compile-flags: --crate-type=lib +//@ revisions: current next +//@ ignore-compare-mode-next-solver (explicit revisions) +//@[current] check-pass +//@[next] compile-flags: -Znext-solver +//@[next] check-fail + +// Test that we avoid incomplete inference when normalizing. Without this, +// `Trait`'s implicit `MetaSized` supertrait requires proving `T::Assoc<_>: MetaSized` +// before checking the `new` arguments, resulting in eagerly constraining the inference +// var to `u32`. This is undesirable and would breaking code. + +pub trait Trait { + type Assoc: OtherTrait; +} + +pub trait OtherTrait { + fn new(r: R) -> R { + r + } +} + +pub fn function() +where + T::Assoc<[u32; 1]>: Clone, +{ + let _x = T::Assoc::new(()); +//[next]~^ ERROR mismatched types +} diff --git a/tests/ui/sized-hierarchy/overflow.current.stderr b/tests/ui/sized-hierarchy/overflow.current.stderr deleted file mode 100644 index e90548aa78c6f..0000000000000 --- a/tests/ui/sized-hierarchy/overflow.current.stderr +++ /dev/null @@ -1,45 +0,0 @@ -error[E0275]: overflow evaluating the requirement `Element: MetaSized` - --> $DIR/overflow.rs:16:16 - | -LL | struct Element(> as ParseTokens>::Output); - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ - | -note: required for `Box` to implement `ParseTokens` - --> $DIR/overflow.rs:12:31 - | -LL | impl ParseTokens for Box { - | - ^^^^^^^^^^^ ^^^^^^ - | | - | unsatisfied trait bound introduced here - = note: 1 redundant requirement hidden - = note: required for `Box>` to implement `ParseTokens` - -error[E0275]: overflow evaluating the requirement `Box: ParseTokens` - --> $DIR/overflow.rs:18:22 - | -LL | impl ParseTokens for Element { - | ^^^^^^^ - | -note: required for `Box>` to implement `ParseTokens` - --> $DIR/overflow.rs:12:31 - | -LL | impl ParseTokens for Box { - | ----------- ^^^^^^^^^^^ ^^^^^^ - | | - | unsatisfied trait bound introduced here -note: required because it appears within the type `Element` - --> $DIR/overflow.rs:16:8 - | -LL | struct Element(> as ParseTokens>::Output); - | ^^^^^^^ -note: required by a bound in `ParseTokens` - --> $DIR/overflow.rs:9:1 - | -LL | / trait ParseTokens { -LL | | type Output; -LL | | } - | |_^ required by this bound in `ParseTokens` - -error: aborting due to 2 previous errors - -For more information about this error, try `rustc --explain E0275`. diff --git a/tests/ui/sized-hierarchy/overflow.rs b/tests/ui/sized-hierarchy/overflow.rs index e1af4885e5396..f8e5dd5d4029b 100644 --- a/tests/ui/sized-hierarchy/overflow.rs +++ b/tests/ui/sized-hierarchy/overflow.rs @@ -1,9 +1,13 @@ //@ compile-flags: --crate-type=lib //@ revisions: current next //@ ignore-compare-mode-next-solver (explicit revisions) +//@[current] check-pass //@[next] check-pass //@[next] compile-flags: -Znext-solver +// FIXME(sized_hierarchy): this is expected to fail in the old solver when there +// isn't a temporary revert of the `sized_hierarchy` feature + use std::marker::PhantomData; trait ParseTokens { @@ -14,8 +18,6 @@ impl ParseTokens for Box { } struct Element(> as ParseTokens>::Output); -//[current]~^ ERROR overflow evaluating impl ParseTokens for Element { -//[current]~^ ERROR overflow evaluating type Output = (); } diff --git a/tests/ui/traits/resolve-impl-before-constrain-check.rs b/tests/ui/traits/resolve-impl-before-constrain-check.rs index 50d1a87455139..87f9c241e402b 100644 --- a/tests/ui/traits/resolve-impl-before-constrain-check.rs +++ b/tests/ui/traits/resolve-impl-before-constrain-check.rs @@ -15,7 +15,6 @@ use foo::*; fn test() -> impl Sized { <() as Callable>::call() -//~^ ERROR: type annotations needed } fn main() {} diff --git a/tests/ui/traits/resolve-impl-before-constrain-check.stderr b/tests/ui/traits/resolve-impl-before-constrain-check.stderr index 13fbfdb855cbf..e8e569ba625ee 100644 --- a/tests/ui/traits/resolve-impl-before-constrain-check.stderr +++ b/tests/ui/traits/resolve-impl-before-constrain-check.stderr @@ -4,13 +4,6 @@ error[E0207]: the type parameter `V` is not constrained by the impl trait, self LL | impl Callable for () { | ^ unconstrained type parameter -error[E0282]: type annotations needed - --> $DIR/resolve-impl-before-constrain-check.rs:17:6 - | -LL | <() as Callable>::call() - | ^^ cannot infer type for type parameter `V` - -error: aborting due to 2 previous errors +error: aborting due to 1 previous error -Some errors have detailed explanations: E0207, E0282. -For more information about an error, try `rustc --explain E0207`. +For more information about this error, try `rustc --explain E0207`.