Ensure that negative auto impls are always applicable

4 files changed, 41 insertions, 23 deletions

diff --git a/tests/ui/specialization/defaultimpl/validation.rs b/tests/ui/specialization/defaultimpl/validation.rs
index 4049c4ea14c..14771be8982 100644
--- a/tests/ui/specialization/defaultimpl/validation.rs
+++ b/tests/ui/specialization/defaultimpl/validation.rs
@@ -6,12 +6,17 @@ struct Z;
 
 default impl S {} //~ ERROR inherent impls cannot be `default`
 
-default unsafe impl Send for S {} //~ ERROR impls of auto traits cannot be default
-//~^ ERROR `S` cannot be sent between threads safely
-default impl !Send for Z {} //~ ERROR impls of auto traits cannot be default
-                            //~^ ERROR negative impls cannot be default impls
+default unsafe impl Send for S {}
+//~^ ERROR impls of auto traits cannot be default
+
+default impl !Send for Z {}
+//~^ ERROR impls of auto traits cannot be default
+//~| ERROR negative impls cannot be default impls
+//~| ERROR `!Send` impl requires `Z: Send` but the struct it is implemented for does not
 
 trait Tr {}
-default impl !Tr for S {} //~ ERROR negative impls cannot be default impls
+
+default impl !Tr for S {}
+//~^ ERROR negative impls cannot be default impls
 
 fn main() {}
diff --git a/tests/ui/specialization/defaultimpl/validation.stderr b/tests/ui/specialization/defaultimpl/validation.stderr
index f56f16162a2..d034386b842 100644
--- a/tests/ui/specialization/defaultimpl/validation.stderr
+++ b/tests/ui/specialization/defaultimpl/validation.stderr
@@ -26,22 +26,20 @@ LL | default unsafe impl Send for S {}
    | |
    | default because of this
 
-error[E0277]: `S` cannot be sent between threads safely
-  --> $DIR/validation.rs:9:1
+error[E0367]: `!Send` impl requires `Z: Send` but the struct it is implemented for does not
+  --> $DIR/validation.rs:12:1
    |
-LL | default unsafe impl Send for S {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `S` cannot be sent between threads safely
-   |
-   = help: the trait `Send` is not implemented for `S`
-   = help: the trait `Send` is implemented for `S`
-   = help: see issue #48214
-help: add `#![feature(trivial_bounds)]` to the crate attributes to enable
+LL | default impl !Send for Z {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^
    |
-LL + #![feature(trivial_bounds)]
+note: the implementor must specify the same requirement
+  --> $DIR/validation.rs:5:1
    |
+LL | struct Z;
+   | ^^^^^^^^
 
 error: impls of auto traits cannot be default
-  --> $DIR/validation.rs:11:15
+  --> $DIR/validation.rs:12:15
    |
 LL | default impl !Send for Z {}
    | -------       ^^^^ auto trait
@@ -49,18 +47,18 @@ LL | default impl !Send for Z {}
    | default because of this
 
 error[E0750]: negative impls cannot be default impls
-  --> $DIR/validation.rs:11:1
+  --> $DIR/validation.rs:12:1
    |
 LL | default impl !Send for Z {}
    | ^^^^^^^      ^
 
 error[E0750]: negative impls cannot be default impls
-  --> $DIR/validation.rs:15:1
+  --> $DIR/validation.rs:19:1
    |
 LL | default impl !Tr for S {}
    | ^^^^^^^      ^
 
 error: aborting due to 6 previous errors; 1 warning emitted
 
-Some errors have detailed explanations: E0277, E0750.
-For more information about an error, try `rustc --explain E0277`.
+Some errors have detailed explanations: E0367, E0750.
+For more information about an error, try `rustc --explain E0367`.
diff --git a/tests/ui/specialization/specialization-overlap-negative.rs b/tests/ui/specialization/specialization-overlap-negative.rs
index 550d3708295..244f21c7ba9 100644
--- a/tests/ui/specialization/specialization-overlap-negative.rs
+++ b/tests/ui/specialization/specialization-overlap-negative.rs
@@ -6,6 +6,8 @@ trait MyTrait {}
 struct TestType<T>(::std::marker::PhantomData<T>);
 
 unsafe impl<T: Clone> Send for TestType<T> {}
-impl<T: MyTrait> !Send for TestType<T> {} //~ ERROR E0751
+impl<T: MyTrait> !Send for TestType<T> {}
+//~^ ERROR found both positive and negative implementation of trait `Send` for type `TestType<_>`
+//~| ERROR `!Send` impl requires `T: MyTrait` but the struct it is implemented for does not
 
 fn main() {}
diff --git a/tests/ui/specialization/specialization-overlap-negative.stderr b/tests/ui/specialization/specialization-overlap-negative.stderr
index a8e99953e2b..4874e897726 100644
--- a/tests/ui/specialization/specialization-overlap-negative.stderr
+++ b/tests/ui/specialization/specialization-overlap-negative.stderr
@@ -16,6 +16,19 @@ LL | unsafe impl<T: Clone> Send for TestType<T> {}
 LL | impl<T: MyTrait> !Send for TestType<T> {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ negative implementation here
 
-error: aborting due to 1 previous error; 1 warning emitted
+error[E0367]: `!Send` impl requires `T: MyTrait` but the struct it is implemented for does not
+  --> $DIR/specialization-overlap-negative.rs:9:9
+   |
+LL | impl<T: MyTrait> !Send for TestType<T> {}
+   |         ^^^^^^^
+   |
+note: the implementor must specify the same requirement
+  --> $DIR/specialization-overlap-negative.rs:6:1
+   |
+LL | struct TestType<T>(::std::marker::PhantomData<T>);
+   | ^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 2 previous errors; 1 warning emitted
 
-For more information about this error, try `rustc --explain E0751`.
+Some errors have detailed explanations: E0367, E0751.
+For more information about an error, try `rustc --explain E0367`.