diff --git a/compiler/rustc_trait_selection/src/solve/fulfill.rs b/compiler/rustc_trait_selection/src/solve/fulfill.rs
index 311dc214de6..0f90c45d032 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/ui/impl-trait/unsized_coercion.next.stderr b/tests/ui/impl-trait/unsized_coercion.next.stderr
index 4cebd26a5be..bea5ddb0aef 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<impl Trait> {
- | ---------------
- | | |
- | | the expected opaque type
- | expected `Box<impl Trait>` because of return type
-...
-LL | Box::new(1u32)
- | ^^^^^^^^^^^^^^ types differ
- |
- = note: expected struct `Box<impl Trait>`
- found struct `Box<u32>`
+error: aborting due to 1 previous error
-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<impl Trait> {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 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
-
-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 b3791b38abc..2cbf0d25d7e 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<impl Trait> {
- //[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<dyn Trait> = 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 d1e1809cf16..28771e01813 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<impl Trait + ?Sized> {
- | ------------------------
- | | |
- | | the expected opaque type
- | expected `Box<impl Trait + ?Sized>` because of return type
-...
-LL | Box::new(1u32)
- | ^^^^^^^^^^^^^^ types differ
- |
- = note: expected struct `Box<impl Trait + ?Sized>`
- found struct `Box<u32>`
+error: aborting due to 1 previous error
-error[E0277]: the trait bound `dyn Send: Trait` is not satisfied
- --> $DIR/unsized_coercion3.rs:11:1
- |
-LL | fn hello() -> Box<impl Trait + ?Sized> {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Trait` is not implemented for `dyn Send`
- |
- = help: the trait `Trait` is implemented for `u32`
-
-error: aborting due to 3 previous errors
-
-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 3bb9f9c2095..52a72b84a8d 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<dyn Send> = 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 c1dd5350e22..ebfbb2955de 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<impl Trait + ?Sized> {
- //[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<impl Trait + ?Sized> {
//[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 1260cca5106..cbd591eec96 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 4ec578a3b7b..3dad6d534fd 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 c6826578658..39422914afc 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 f81f0a23ac3..760e5aa62f2 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`.