diff --git a/compiler/rustc_trait_selection/src/solve/fulfill.rs b/compiler/rustc_trait_selection/src/solve/fulfill.rs index 311dc214de601..0f90c45d0320c 100644 --- a/compiler/rustc_trait_selection/src/solve/fulfill.rs +++ b/compiler/rustc_trait_selection/src/solve/fulfill.rs @@ -346,12 +346,21 @@ fn find_best_leaf_obligation<'tcx>( consider_ambiguities: bool, ) -> PredicateObligation<'tcx> { let obligation = infcx.resolve_vars_if_possible(obligation.clone()); + // FIXME: we use a probe here as the `BestObligation` visitor does not + // check whether it uses candidates which get shadowed by where-bounds. + // + // We should probably fix the visitor to not do so instead, as this also + // means the leaf obligation may be incorrect. infcx - .visit_proof_tree(obligation.clone().into(), &mut BestObligation { - obligation: obligation.clone(), - consider_ambiguities, + .fudge_inference_if_ok(|| { + infcx + .visit_proof_tree(obligation.clone().into(), &mut BestObligation { + obligation: obligation.clone(), + consider_ambiguities, + }) + .break_value() + .ok_or(()) }) - .break_value() .unwrap_or(obligation) } diff --git a/tests/crashes/129444.rs b/tests/crashes/129444.rs deleted file mode 100644 index b1b547b5191bd..0000000000000 --- a/tests/crashes/129444.rs +++ /dev/null @@ -1,15 +0,0 @@ -//@ known-bug: rust-lang/rust#129444 - -//@ compile-flags: -Znext-solver=coherence - -trait Trait { - type Assoc; -} - -struct W(*mut T); -impl Trait for W>> {} - -trait NoOverlap {} -impl>> NoOverlap for T {} - -impl> NoOverlap for W {} diff --git a/tests/ui/coherence/fuzzing/best-obligation-ICE.rs b/tests/ui/coherence/fuzzing/best-obligation-ICE.rs new file mode 100644 index 0000000000000..49f40b579d400 --- /dev/null +++ b/tests/ui/coherence/fuzzing/best-obligation-ICE.rs @@ -0,0 +1,20 @@ +// A regression test for #129444. This previously ICE'd as +// computing the best obligation for one ambiguous obligation +// added spurious inference constraints which caused another +// candidate to pass. +trait Trait { + type Assoc; +} + +struct W(*mut T); +impl Trait for W>> {} +//~^ ERROR the trait bound `W>: Trait` is not satisfied +//~| ERROR the trait bound `W: Trait` is not satisfied +//~| ERROR the trait bound `T: Trait` is not satisfied +//~| ERROR not all trait items implemented, missing: `Assoc` + +trait NoOverlap {} +impl NoOverlap for T {} +impl> NoOverlap for W {} +//~^ ERROR conflicting implementations of trait `NoOverlap` for type `W>>>` +fn main() {} diff --git a/tests/ui/coherence/fuzzing/best-obligation-ICE.stderr b/tests/ui/coherence/fuzzing/best-obligation-ICE.stderr new file mode 100644 index 0000000000000..88de8023f6d79 --- /dev/null +++ b/tests/ui/coherence/fuzzing/best-obligation-ICE.stderr @@ -0,0 +1,69 @@ +error[E0277]: the trait bound `W>: Trait` is not satisfied + --> $DIR/best-obligation-ICE.rs:10:19 + | +LL | impl Trait for W>> {} + | ^^^^^^^^^^ the trait `Trait` is not implemented for `W>` + | +note: required by a bound in `W` + --> $DIR/best-obligation-ICE.rs:9:13 + | +LL | struct W(*mut T); + | ^^^^^ required by this bound in `W` +help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement + | +LL | impl Trait for W>> where W>: Trait {} + | ++++++++++++++++++++ + +error[E0277]: the trait bound `W: Trait` is not satisfied + --> $DIR/best-obligation-ICE.rs:10:19 + | +LL | impl Trait for W>> {} + | ^^^^^^^^^^ the trait `Trait` is not implemented for `W` + | +note: required by a bound in `W` + --> $DIR/best-obligation-ICE.rs:9:13 + | +LL | struct W(*mut T); + | ^^^^^ required by this bound in `W` +help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement + | +LL | impl Trait for W>> where W: Trait {} + | +++++++++++++++++ + +error[E0277]: the trait bound `T: Trait` is not satisfied + --> $DIR/best-obligation-ICE.rs:10:19 + | +LL | impl Trait for W>> {} + | ^^^^^^^^^^ the trait `Trait` is not implemented for `T` + | +note: required by a bound in `W` + --> $DIR/best-obligation-ICE.rs:9:13 + | +LL | struct W(*mut T); + | ^^^^^ required by this bound in `W` +help: consider restricting type parameter `T` + | +LL | impl Trait for W>> {} + | +++++++ + +error[E0046]: not all trait items implemented, missing: `Assoc` + --> $DIR/best-obligation-ICE.rs:10:1 + | +LL | type Assoc; + | ---------- `Assoc` from trait +... +LL | impl Trait for W>> {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing `Assoc` in implementation + +error[E0119]: conflicting implementations of trait `NoOverlap` for type `W>>>` + --> $DIR/best-obligation-ICE.rs:18:1 + | +LL | impl NoOverlap for T {} + | ------------------------------ first implementation here +LL | impl> NoOverlap for W {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `W>>>` + +error: aborting due to 5 previous errors + +Some errors have detailed explanations: E0046, E0119, E0277. +For more information about an error, try `rustc --explain E0046`. diff --git a/tests/ui/impl-trait/unsized_coercion.next.stderr b/tests/ui/impl-trait/unsized_coercion.next.stderr index 4cebd26a5bee6..bea5ddb0aefcc 100644 --- a/tests/ui/impl-trait/unsized_coercion.next.stderr +++ b/tests/ui/impl-trait/unsized_coercion.next.stderr @@ -1,35 +1,11 @@ error[E0277]: the size for values of type `dyn Trait` cannot be known at compilation time - --> $DIR/unsized_coercion.rs:15:17 + --> $DIR/unsized_coercion.rs:14:17 | LL | let x = hello(); | ^^^^^^^ doesn't have a size known at compile-time | = help: the trait `Sized` is not implemented for `dyn Trait` -error[E0308]: mismatched types - --> $DIR/unsized_coercion.rs:19:5 - | -LL | fn hello() -> Box { - | --------------- - | | | - | | the expected opaque type - | expected `Box` because of return type -... -LL | Box::new(1u32) - | ^^^^^^^^^^^^^^ types differ - | - = note: expected struct `Box` - found struct `Box` - -error[E0277]: the size for values of type `dyn Trait` cannot be known at compilation time - --> $DIR/unsized_coercion.rs:12:1 - | -LL | fn hello() -> Box { - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time - | - = help: the trait `Sized` is not implemented for `dyn Trait` - -error: aborting due to 3 previous errors +error: aborting due to 1 previous error -Some errors have detailed explanations: E0277, E0308. -For more information about an error, try `rustc --explain E0277`. +For more information about this error, try `rustc --explain E0277`. diff --git a/tests/ui/impl-trait/unsized_coercion.rs b/tests/ui/impl-trait/unsized_coercion.rs index b3791b38abc2d..2cbf0d25d7ec6 100644 --- a/tests/ui/impl-trait/unsized_coercion.rs +++ b/tests/ui/impl-trait/unsized_coercion.rs @@ -10,13 +10,12 @@ trait Trait {} impl Trait for u32 {} fn hello() -> Box { - //[next]~^ ERROR the size for values of type `dyn Trait` cannot be known at compilation time if true { let x = hello(); //[next]~^ ERROR: the size for values of type `dyn Trait` cannot be known at compilation time let y: Box = x; } - Box::new(1u32) //[next]~ ERROR: mismatched types + Box::new(1u32) } fn main() {} diff --git a/tests/ui/impl-trait/unsized_coercion3.next.stderr b/tests/ui/impl-trait/unsized_coercion3.next.stderr index d1e1809cf1656..28771e01813ae 100644 --- a/tests/ui/impl-trait/unsized_coercion3.next.stderr +++ b/tests/ui/impl-trait/unsized_coercion3.next.stderr @@ -1,35 +1,11 @@ error[E0277]: the trait bound `dyn Send: Trait` is not satisfied - --> $DIR/unsized_coercion3.rs:14:17 + --> $DIR/unsized_coercion3.rs:13:17 | LL | let x = hello(); | ^^^^^^^ the trait `Trait` is not implemented for `dyn Send` | = help: the trait `Trait` is implemented for `u32` -error[E0308]: mismatched types - --> $DIR/unsized_coercion3.rs:19:5 - | -LL | fn hello() -> Box { - | ------------------------ - | | | - | | the expected opaque type - | expected `Box` because of return type -... -LL | Box::new(1u32) - | ^^^^^^^^^^^^^^ types differ - | - = note: expected struct `Box` - found struct `Box` - -error[E0277]: the trait bound `dyn Send: Trait` is not satisfied - --> $DIR/unsized_coercion3.rs:11:1 - | -LL | fn hello() -> Box { - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Trait` is not implemented for `dyn Send` - | - = help: the trait `Trait` is implemented for `u32` - -error: aborting due to 3 previous errors +error: aborting due to 1 previous error -Some errors have detailed explanations: E0277, E0308. -For more information about an error, try `rustc --explain E0277`. +For more information about this error, try `rustc --explain E0277`. diff --git a/tests/ui/impl-trait/unsized_coercion3.old.stderr b/tests/ui/impl-trait/unsized_coercion3.old.stderr index 3bb9f9c209510..52a72b84a8dd6 100644 --- a/tests/ui/impl-trait/unsized_coercion3.old.stderr +++ b/tests/ui/impl-trait/unsized_coercion3.old.stderr @@ -1,5 +1,5 @@ error[E0277]: the size for values of type `impl Trait + ?Sized` cannot be known at compilation time - --> $DIR/unsized_coercion3.rs:16:32 + --> $DIR/unsized_coercion3.rs:15:32 | LL | let y: Box = x; | ^ doesn't have a size known at compile-time diff --git a/tests/ui/impl-trait/unsized_coercion3.rs b/tests/ui/impl-trait/unsized_coercion3.rs index c1dd5350e229a..ebfbb2955de55 100644 --- a/tests/ui/impl-trait/unsized_coercion3.rs +++ b/tests/ui/impl-trait/unsized_coercion3.rs @@ -9,7 +9,6 @@ trait Trait {} impl Trait for u32 {} fn hello() -> Box { - //[next]~^ ERROR: the trait bound `dyn Send: Trait` is not satisfied if true { let x = hello(); //[next]~^ ERROR: the trait bound `dyn Send: Trait` is not satisfied @@ -17,7 +16,6 @@ fn hello() -> Box { //[old]~^ ERROR: the size for values of type `impl Trait + ?Sized` cannot be know } Box::new(1u32) - //[next]~^ ERROR: mismatched types } fn main() {} diff --git a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.rs b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.rs index 1260cca510680..cbd591eec96c0 100644 --- a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.rs +++ b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.rs @@ -14,13 +14,7 @@ fn main() { fn weird0() -> impl Sized + !Sized {} //~^ ERROR the trait bound `(): !Sized` is not satisfied -//~| ERROR the trait bound `(): !Sized` is not satisfied -//~| ERROR the trait bound `(): !Sized` is not satisfied fn weird1() -> impl !Sized + Sized {} //~^ ERROR the trait bound `(): !Sized` is not satisfied -//~| ERROR the trait bound `(): !Sized` is not satisfied -//~| ERROR the trait bound `(): !Sized` is not satisfied fn weird2() -> impl !Sized {} //~^ ERROR the trait bound `(): !Sized` is not satisfied -//~| ERROR the trait bound `(): !Sized` is not satisfied -//~| ERROR the trait bound `(): !Sized` is not satisfied diff --git a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.stderr b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.stderr index 4ec578a3b7bc2..3dad6d534fd83 100644 --- a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.stderr +++ b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.stderr @@ -5,53 +5,17 @@ LL | fn weird0() -> impl Sized + !Sized {} | ^^^^^^^^^^^^^^^^^^^ the trait bound `(): !Sized` is not satisfied error[E0277]: the trait bound `(): !Sized` is not satisfied - --> $DIR/opaque-type-unsatisfied-bound.rs:15:36 - | -LL | fn weird0() -> impl Sized + !Sized {} - | ^^ the trait bound `(): !Sized` is not satisfied - -error[E0277]: the trait bound `(): !Sized` is not satisfied - --> $DIR/opaque-type-unsatisfied-bound.rs:15:1 - | -LL | fn weird0() -> impl Sized + !Sized {} - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait bound `(): !Sized` is not satisfied - -error[E0277]: the trait bound `(): !Sized` is not satisfied - --> $DIR/opaque-type-unsatisfied-bound.rs:19:16 + --> $DIR/opaque-type-unsatisfied-bound.rs:17:16 | LL | fn weird1() -> impl !Sized + Sized {} | ^^^^^^^^^^^^^^^^^^^ the trait bound `(): !Sized` is not satisfied error[E0277]: the trait bound `(): !Sized` is not satisfied - --> $DIR/opaque-type-unsatisfied-bound.rs:19:36 - | -LL | fn weird1() -> impl !Sized + Sized {} - | ^^ the trait bound `(): !Sized` is not satisfied - -error[E0277]: the trait bound `(): !Sized` is not satisfied - --> $DIR/opaque-type-unsatisfied-bound.rs:19:1 - | -LL | fn weird1() -> impl !Sized + Sized {} - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait bound `(): !Sized` is not satisfied - -error[E0277]: the trait bound `(): !Sized` is not satisfied - --> $DIR/opaque-type-unsatisfied-bound.rs:23:16 + --> $DIR/opaque-type-unsatisfied-bound.rs:19:16 | LL | fn weird2() -> impl !Sized {} | ^^^^^^^^^^^ the trait bound `(): !Sized` is not satisfied -error[E0277]: the trait bound `(): !Sized` is not satisfied - --> $DIR/opaque-type-unsatisfied-bound.rs:23:28 - | -LL | fn weird2() -> impl !Sized {} - | ^^ the trait bound `(): !Sized` is not satisfied - -error[E0277]: the trait bound `(): !Sized` is not satisfied - --> $DIR/opaque-type-unsatisfied-bound.rs:23:1 - | -LL | fn weird2() -> impl !Sized {} - | ^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait bound `(): !Sized` is not satisfied - error[E0277]: the trait bound `impl !Trait: Trait` is not satisfied --> $DIR/opaque-type-unsatisfied-bound.rs:12:13 | @@ -66,6 +30,6 @@ note: required by a bound in `consume` LL | fn consume(_: impl Trait) {} | ^^^^^ required by this bound in `consume` -error: aborting due to 10 previous errors +error: aborting due to 4 previous errors For more information about this error, try `rustc --explain E0277`. diff --git a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.rs b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.rs index c6826578658fd..39422914afcdd 100644 --- a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.rs +++ b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.rs @@ -4,7 +4,5 @@ fn produce() -> impl !Fn<(u32,)> {} //~^ ERROR the trait bound `(): !Fn(u32)` is not satisfied -//~| ERROR the trait bound `(): !Fn(u32)` is not satisfied -//~| ERROR the trait bound `(): !Fn(u32)` is not satisfied fn main() {} diff --git a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.stderr b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.stderr index f81f0a23ac315..760e5aa62f2c1 100644 --- a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.stderr +++ b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.stderr @@ -4,18 +4,6 @@ error[E0277]: the trait bound `(): !Fn(u32)` is not satisfied LL | fn produce() -> impl !Fn<(u32,)> {} | ^^^^^^^^^^^^^^^^ the trait bound `(): !Fn(u32)` is not satisfied -error[E0277]: the trait bound `(): !Fn(u32)` is not satisfied - --> $DIR/opaque-type-unsatisfied-fn-bound.rs:5:34 - | -LL | fn produce() -> impl !Fn<(u32,)> {} - | ^^ the trait bound `(): !Fn(u32)` is not satisfied - -error[E0277]: the trait bound `(): !Fn(u32)` is not satisfied - --> $DIR/opaque-type-unsatisfied-fn-bound.rs:5:1 - | -LL | fn produce() -> impl !Fn<(u32,)> {} - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait bound `(): !Fn(u32)` is not satisfied - -error: aborting due to 3 previous errors +error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0277`.