Avoid follow up "type annotations needed" errors in case there were a…

…lready coherence errors for the same trait
rust-lang · Feb 1, 2024 · 08e7773 · 08e7773
1 parent ad42fa1
commit 08e7773
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Showing 65 changed files with 135 additions and 1,120 deletions.
diff --git a/compiler/rustc_hir_analysis/src/check/wfcheck.rs b/compiler/rustc_hir_analysis/src/check/wfcheck.rs
@@ -1292,6 +1292,11 @@ fn check_impl<'tcx>(
                 // therefore don't need to be WF (the trait's `Self: Trait` predicate
                 // won't hold).
                 let trait_ref = tcx.impl_trait_ref(item.owner_id).unwrap().instantiate_identity();
+                if let Err(guar) = tcx.ensure().coherent_trait(trait_ref.def_id) {
+                    // Avoid bogus "type annotations needed `Foo: Bar`" errors on `impl Bar for Foo` in case
+                    // other `Foo` impls are incoherent.
+                    wfcx.infcx.set_tainted_by_errors(guar);
+                }
                 let trait_ref = wfcx.normalize(
                     ast_trait_ref.path.span,
                     Some(WellFormedLoc::Ty(item.hir_id().expect_owner().def_id)),

diff --git a/tests/ui/async-await/in-trait/coherence-constrained.rs b/tests/ui/async-await/in-trait/coherence-constrained.rs
@@ -11,7 +11,6 @@ trait Foo {
 struct Bar;
 
 impl Foo for Bar {
-    //~^ ERROR type annotations needed
     type T = ();
     //~^ ERROR type annotations needed
 
@@ -22,7 +21,6 @@ impl Foo for Bar {
 
 impl Foo for Bar {
     //~^ ERROR conflicting implementations of trait `Foo` for type `Bar`
-    //~| ERROR type annotations needed
     type T = ();
     //~^ ERROR type annotations needed
 

diff --git a/tests/ui/async-await/in-trait/coherence-constrained.stderr b/tests/ui/async-await/in-trait/coherence-constrained.stderr
@@ -1,49 +1,34 @@
 error[E0284]: type annotations needed: cannot satisfy `<Bar as Foo>::T == ()`
-  --> $DIR/coherence-constrained.rs:18:5
+  --> $DIR/coherence-constrained.rs:17:5
    |
 LL |     async fn foo(&self) {}
    |     ^^^^^^^^^^^^^^^^^^^ cannot satisfy `<Bar as Foo>::T == ()`
 
 error[E0284]: type annotations needed: cannot satisfy `<Bar as Foo>::T == ()`
-  --> $DIR/coherence-constrained.rs:29:5
+  --> $DIR/coherence-constrained.rs:27:5
    |
 LL |     async fn foo(&self) {}
    |     ^^^^^^^^^^^^^^^^^^^ cannot satisfy `<Bar as Foo>::T == ()`
 
 error[E0119]: conflicting implementations of trait `Foo` for type `Bar`
-  --> $DIR/coherence-constrained.rs:23:1
+  --> $DIR/coherence-constrained.rs:22:1
    |
 LL | impl Foo for Bar {
    | ---------------- first implementation here
 ...
 LL | impl Foo for Bar {
    | ^^^^^^^^^^^^^^^^ conflicting implementation for `Bar`
 
-error[E0283]: type annotations needed: cannot satisfy `Bar: Foo`
-  --> $DIR/coherence-constrained.rs:13:14
-   |
-LL | impl Foo for Bar {
-   |              ^^^
-   |
-note: multiple `impl`s satisfying `Bar: Foo` found
-  --> $DIR/coherence-constrained.rs:13:1
-   |
-LL | impl Foo for Bar {
-   | ^^^^^^^^^^^^^^^^
-...
-LL | impl Foo for Bar {
-   | ^^^^^^^^^^^^^^^^
-
 error[E0284]: type annotations needed
-  --> $DIR/coherence-constrained.rs:15:14
+  --> $DIR/coherence-constrained.rs:14:14
    |
 LL |     type T = ();
    |              ^^ cannot infer type
    |
    = note: cannot satisfy `<Bar as Foo>::T == _`
 
 error[E0284]: type annotations needed: cannot satisfy `<Bar as Foo>::{opaque#0}<'_> == impl Future<Output = ()>`
-  --> $DIR/coherence-constrained.rs:18:5
+  --> $DIR/coherence-constrained.rs:17:5
    |
 LL |     async fn foo(&self) {}
    |     ^^^^^^^^^^^^^^^^^^^ cannot satisfy `<Bar as Foo>::{opaque#0}<'_> == impl Future<Output = ()>`
@@ -56,31 +41,16 @@ LL |     async fn foo(&self) -> Self::T;
    |
    = note: cannot satisfy `<Bar as Foo>::{opaque#0}<'_> == _`
 
-error[E0283]: type annotations needed: cannot satisfy `Bar: Foo`
-  --> $DIR/coherence-constrained.rs:23:14
-   |
-LL | impl Foo for Bar {
-   |              ^^^
-   |
-note: multiple `impl`s satisfying `Bar: Foo` found
-  --> $DIR/coherence-constrained.rs:13:1
-   |
-LL | impl Foo for Bar {
-   | ^^^^^^^^^^^^^^^^
-...
-LL | impl Foo for Bar {
-   | ^^^^^^^^^^^^^^^^
-
 error[E0284]: type annotations needed
-  --> $DIR/coherence-constrained.rs:26:14
+  --> $DIR/coherence-constrained.rs:24:14
    |
 LL |     type T = ();
    |              ^^ cannot infer type
    |
    = note: cannot satisfy `<Bar as Foo>::T == _`
 
 error[E0284]: type annotations needed: cannot satisfy `<Bar as Foo>::{opaque#0}<'_> == impl Future<Output = ()>`
-  --> $DIR/coherence-constrained.rs:29:5
+  --> $DIR/coherence-constrained.rs:27:5
    |
 LL |     async fn foo(&self) {}
    |     ^^^^^^^^^^^^^^^^^^^ cannot satisfy `<Bar as Foo>::{opaque#0}<'_> == impl Future<Output = ()>`
@@ -94,7 +64,7 @@ LL |     async fn foo(&self) -> Self::T;
    = note: cannot satisfy `<Bar as Foo>::{opaque#0}<'_> == _`
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
-error: aborting due to 11 previous errors
+error: aborting due to 9 previous errors
 
-Some errors have detailed explanations: E0119, E0283, E0284.
+Some errors have detailed explanations: E0119, E0284.
 For more information about an error, try `rustc --explain E0119`.
diff --git a/tests/ui/async-await/issue-67651.rs b/tests/ui/async-await/issue-67651.rs
@@ -5,14 +5,11 @@ trait From {
 }
 
 impl From for () {
-//~^ ERROR type annotations needed
     fn from() {}
 }
 
 impl From for () {
 //~^ ERROR conflicting implementations of trait
-//~| ERROR type annotations needed
-    fn from() {}
 }
 
 fn bar() -> impl core::future::Future<Output = ()> {

diff --git a/tests/ui/async-await/issue-67651.stderr b/tests/ui/async-await/issue-67651.stderr
@@ -1,44 +1,14 @@
 error[E0119]: conflicting implementations of trait `From` for type `()`
-  --> $DIR/issue-67651.rs:12:1
+  --> $DIR/issue-67651.rs:11:1
    |
 LL | impl From for () {
    | ---------------- first implementation here
 ...
 LL | impl From for () {
    | ^^^^^^^^^^^^^^^^ conflicting implementation for `()`
 
-error[E0283]: type annotations needed: cannot satisfy `(): From`
-  --> $DIR/issue-67651.rs:7:15
-   |
-LL | impl From for () {
-   |               ^^
-   |
-note: multiple `impl`s satisfying `(): From` found
-  --> $DIR/issue-67651.rs:7:1
-   |
-LL | impl From for () {
-   | ^^^^^^^^^^^^^^^^
-...
-LL | impl From for () {
-   | ^^^^^^^^^^^^^^^^
-
-error[E0283]: type annotations needed: cannot satisfy `(): From`
-  --> $DIR/issue-67651.rs:12:15
-   |
-LL | impl From for () {
-   |               ^^
-   |
-note: multiple `impl`s satisfying `(): From` found
-  --> $DIR/issue-67651.rs:7:1
-   |
-LL | impl From for () {
-   | ^^^^^^^^^^^^^^^^
-...
-LL | impl From for () {
-   | ^^^^^^^^^^^^^^^^
-
 error[E0790]: cannot call associated function on trait without specifying the corresponding `impl` type
-  --> $DIR/issue-67651.rs:19:18
+  --> $DIR/issue-67651.rs:16:18
    |
 LL |     fn from();
    |     ---------- `From::from` defined here
@@ -51,7 +21,7 @@ help: use a fully-qualified path to a specific available implementation
 LL |     async move { </* self type */ as From>::from() }
    |                  +++++++++++++++++++     +
 
-error: aborting due to 4 previous errors
+error: aborting due to 2 previous errors
 
-Some errors have detailed explanations: E0119, E0283, E0790.
+Some errors have detailed explanations: E0119, E0790.
 For more information about an error, try `rustc --explain E0119`.
diff --git a/tests/ui/coherence/coherence-blanket-conflicts-with-specific-cross-crate.rs b/tests/ui/coherence/coherence-blanket-conflicts-with-specific-cross-crate.rs
@@ -14,7 +14,6 @@ impl Go for MyThingy {
 
 impl GoMut for MyThingy {
 //~^ ERROR E0119
-//~| ERROR E0283
     fn go_mut(&mut self, arg: isize) { }
 }
 

diff --git a/tests/ui/coherence/coherence-blanket-conflicts-with-specific-cross-crate.stderr b/tests/ui/coherence/coherence-blanket-conflicts-with-specific-cross-crate.stderr
@@ -8,22 +8,6 @@ LL | impl GoMut for MyThingy {
            - impl<G> GoMut for G
              where G: Go;
 
-error[E0283]: type annotations needed: cannot satisfy `MyThingy: GoMut`
-  --> $DIR/coherence-blanket-conflicts-with-specific-cross-crate.rs:15:16
-   |
-LL | impl GoMut for MyThingy {
-   |                ^^^^^^^^
-   |
-note: multiple `impl`s satisfying `MyThingy: GoMut` found
-  --> $DIR/coherence-blanket-conflicts-with-specific-cross-crate.rs:15:1
-   |
-LL | impl GoMut for MyThingy {
-   | ^^^^^^^^^^^^^^^^^^^^^^^
-   = note: and another `impl` found in the `go_trait` crate:
-           - impl<G> GoMut for G
-             where G: Go;
-
-error: aborting due to 2 previous errors
+error: aborting due to 1 previous error
 
-Some errors have detailed explanations: E0119, E0283.
-For more information about an error, try `rustc --explain E0119`.
+For more information about this error, try `rustc --explain E0119`.
diff --git a/tests/ui/coherence/coherence-blanket-conflicts-with-specific-multidispatch.rs b/tests/ui/coherence/coherence-blanket-conflicts-with-specific-multidispatch.rs
@@ -21,7 +21,6 @@ struct MyType {
 
 impl MyTrait<MyType> for MyType {
 //~^ ERROR E0119
-//~| ERROR type annotations needed
     fn get(&self) -> usize { (*self).clone() }
     //~^ ERROR incompatible type
 }

diff --git a/tests/ui/coherence/coherence-blanket-conflicts-with-specific-multidispatch.stderr b/tests/ui/coherence/coherence-blanket-conflicts-with-specific-multidispatch.stderr
@@ -7,23 +7,8 @@ LL | impl<T> MyTrait<T> for T {
 LL | impl MyTrait<MyType> for MyType {
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `MyType`
 
-error[E0283]: type annotations needed: cannot satisfy `MyType: MyTrait<MyType>`
-  --> $DIR/coherence-blanket-conflicts-with-specific-multidispatch.rs:22:26
-   |
-LL | impl MyTrait<MyType> for MyType {
-   |                          ^^^^^^
-   |
-note: multiple `impl`s satisfying `MyType: MyTrait<MyType>` found
-  --> $DIR/coherence-blanket-conflicts-with-specific-multidispatch.rs:11:1
-   |
-LL | impl<T> MyTrait<T> for T {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^
-...
-LL | impl MyTrait<MyType> for MyType {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
 error[E0053]: method `get` has an incompatible type for trait
-  --> $DIR/coherence-blanket-conflicts-with-specific-multidispatch.rs:25:22
+  --> $DIR/coherence-blanket-conflicts-with-specific-multidispatch.rs:24:22
    |
 LL |     fn get(&self) -> usize { (*self).clone() }
    |                      ^^^^^
@@ -39,7 +24,7 @@ LL |     fn get(&self) -> T;
    = note: expected signature `fn(&MyType) -> MyType`
               found signature `fn(&MyType) -> usize`
 
-error: aborting due to 3 previous errors
+error: aborting due to 2 previous errors
 
-Some errors have detailed explanations: E0053, E0119, E0283.
+Some errors have detailed explanations: E0053, E0119.
 For more information about an error, try `rustc --explain E0053`.
diff --git a/tests/ui/coherence/coherence-blanket-conflicts-with-specific-trait.rs b/tests/ui/coherence/coherence-blanket-conflicts-with-specific-trait.rs
@@ -19,7 +19,6 @@ struct MyType {
 
 impl MyTrait for MyType {
 //~^ ERROR E0119
-//~| ERROR type annotations needed
     fn get(&self) -> usize { self.dummy }
 }
 

diff --git a/tests/ui/coherence/coherence-blanket-conflicts-with-specific-trait.stderr b/tests/ui/coherence/coherence-blanket-conflicts-with-specific-trait.stderr
@@ -7,22 +7,6 @@ LL | impl<T:OtherTrait> MyTrait for T {
 LL | impl MyTrait for MyType {
    | ^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `MyType`
 
-error[E0283]: type annotations needed: cannot satisfy `MyType: MyTrait`
-  --> $DIR/coherence-blanket-conflicts-with-specific-trait.rs:20:18
-   |
-LL | impl MyTrait for MyType {
-   |                  ^^^^^^
-   |
-note: multiple `impl`s satisfying `MyType: MyTrait` found
-  --> $DIR/coherence-blanket-conflicts-with-specific-trait.rs:12:1
-   |
-LL | impl<T:OtherTrait> MyTrait for T {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-...
-LL | impl MyTrait for MyType {
-   | ^^^^^^^^^^^^^^^^^^^^^^^
-
-error: aborting due to 2 previous errors
+error: aborting due to 1 previous error
 
-Some errors have detailed explanations: E0119, E0283.
-For more information about an error, try `rustc --explain E0119`.
+For more information about this error, try `rustc --explain E0119`.
diff --git a/tests/ui/coherence/coherence-blanket-conflicts-with-specific.rs b/tests/ui/coherence/coherence-blanket-conflicts-with-specific.rs
@@ -18,7 +18,6 @@ struct MyType {
 
 impl MyTrait for MyType {
 //~^ ERROR E0119
-//~| ERROR type annotations needed
     fn get(&self) -> usize { self.dummy }
 }
 

diff --git a/tests/ui/coherence/coherence-blanket-conflicts-with-specific.stderr b/tests/ui/coherence/coherence-blanket-conflicts-with-specific.stderr
@@ -7,22 +7,6 @@ LL | impl<T> MyTrait for T {
 LL | impl MyTrait for MyType {
    | ^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `MyType`
 
-error[E0283]: type annotations needed: cannot satisfy `MyType: MyTrait`
-  --> $DIR/coherence-blanket-conflicts-with-specific.rs:19:18
-   |
-LL | impl MyTrait for MyType {
-   |                  ^^^^^^
-   |
-note: multiple `impl`s satisfying `MyType: MyTrait` found
-  --> $DIR/coherence-blanket-conflicts-with-specific.rs:11:1
-   |
-LL | impl<T> MyTrait for T {
-   | ^^^^^^^^^^^^^^^^^^^^^
-...
-LL | impl MyTrait for MyType {
-   | ^^^^^^^^^^^^^^^^^^^^^^^
-
-error: aborting due to 2 previous errors
+error: aborting due to 1 previous error
 
-Some errors have detailed explanations: E0119, E0283.
-For more information about an error, try `rustc --explain E0119`.
+For more information about this error, try `rustc --explain E0119`.
diff --git a/tests/ui/coherence/coherence-conflicting-negative-trait-impl.rs b/tests/ui/coherence/coherence-conflicting-negative-trait-impl.rs
@@ -7,7 +7,6 @@ trait MyTrait {}
 struct TestType<T>(::std::marker::PhantomData<T>);
 
 unsafe impl<T: MyTrait + 'static> Send for TestType<T> {}
-//~^ ERROR: type annotations needed
 
 impl<T: MyTrait> !Send for TestType<T> {} //~ ERROR found both positive and negative implementation