Avoid silencing relevant follow-up errors

Author: oli-obk

compiler/rustc_hir_analysis/src/lib.rs

@@ -168,12 +168,9 @@ pub fn check_crate(tcx: TyCtxt<'_>) -> Result<(), ErrorGuaranteed> {
 
     // this ensures that later parts of type checking can assume that items
     // have valid types and not error
-    // FIXME(matthewjasper) We shouldn't need to use `track_errors`.
-    tcx.sess.track_errors(|| {
-        tcx.sess.time("type_collecting", || {
-            tcx.hir().for_each_module(|module| tcx.ensure().collect_mod_item_types(module))
-        });
-    })?;
+    tcx.sess.time("type_collecting", || {
+        tcx.hir().for_each_module(|module| tcx.ensure().collect_mod_item_types(module))
+    });
 
     if tcx.features().rustc_attrs {
         tcx.sess.track_errors(|| {

compiler/rustc_hir_analysis/src/outlives/test.rs

@@ -8,14 +8,12 @@ pub fn test_inferred_outlives(tcx: TyCtxt<'_>) {
         // attribute and report an error with various results if found.
         if tcx.has_attr(id.owner_id, sym::rustc_outlives) {
             let inferred_outlives_of = tcx.inferred_outlives_of(id.owner_id);
-            struct_span_err!(
-                tcx.sess,
-                tcx.def_span(id.owner_id),
-                E0640,
-                "{:?}",
-                inferred_outlives_of
-            )
-            .emit();
+            let mut err =
+                struct_span_err!(tcx.sess, tcx.def_span(id.owner_id), E0640, "rustc_outlives");
+            for &(clause, span) in inferred_outlives_of {
+                err.span_note(span, format!("{clause}"));
+            }
+            err.emit();
         }
     }
 }

compiler/rustc_trait_selection/src/traits/mod.rs

@@ -279,6 +279,12 @@ pub fn normalize_param_env_or_error<'tcx>(
                 }
 
                 fn fold_const(&mut self, c: ty::Const<'tcx>) -> ty::Const<'tcx> {
+                    // FIXME(return_type_notation): track binders in this normalizer, as
+                    // `ty::Const::normalize` can only work with properly preserved binders.
+
+                    if c.has_escaping_bound_vars() {
+                        return ty::Const::new_misc_error(self.0, c.ty());
+                    }
                     // While it is pretty sus to be evaluating things with an empty param env, it
                     // should actually be okay since without `feature(generic_const_exprs)` the only
                     // const arguments that have a non-empty param env are array repeat counts. These

tests/ui/associated-inherent-types/issue-109071.no_gate.stderr

@@ -13,7 +13,7 @@ LL | impl<T> Windows {
 note: struct defined here, with 1 generic parameter: `T`
   --> $DIR/issue-109071.rs:5:8
    |
-LL | struct Windows<T> {}
+LL | struct Windows<T> { t: T }
    |        ^^^^^^^ -
 help: add missing generic argument
    |
@@ -30,7 +30,7 @@ LL |     type Item = &[T];
    = help: add `#![feature(inherent_associated_types)]` to the crate attributes to enable
 
 error[E0223]: ambiguous associated type
-  --> $DIR/issue-109071.rs:15:22
+  --> $DIR/issue-109071.rs:16:22
    |
 LL |     fn T() -> Option<Self::Item> {}
    |                      ^^^^^^^^^^ help: use fully-qualified syntax: `<Windows<T> as IntoIterator>::Item`

tests/ui/associated-inherent-types/issue-109071.rs

@@ -2,18 +2,20 @@
 #![cfg_attr(with_gate, feature(inherent_associated_types))]
 #![cfg_attr(with_gate, allow(incomplete_features))]
 
-struct Windows<T> {}
+struct Windows<T> { t: T }
 
 impl<T> Windows { //~ ERROR: missing generics for struct `Windows`
     type Item = &[T]; //~ ERROR: `&` without an explicit lifetime name cannot be used here
     //[no_gate]~^ ERROR: inherent associated types are unstable
 
     fn next() -> Option<Self::Item> {}
+    //[with_gate]~^ ERROR type annotations needed
 }
 
 impl<T> Windows<T> {
     fn T() -> Option<Self::Item> {}
     //[no_gate]~^ ERROR: ambiguous associated type
+    //[with_gate]~^^ ERROR type annotations needed
 }
 
 fn main() {}

tests/ui/associated-inherent-types/issue-109071.with_gate.stderr

@@ -13,14 +13,26 @@ LL | impl<T> Windows {
 note: struct defined here, with 1 generic parameter: `T`
   --> $DIR/issue-109071.rs:5:8
    |
-LL | struct Windows<T> {}
+LL | struct Windows<T> { t: T }
    |        ^^^^^^^ -
 help: add missing generic argument
    |
 LL | impl<T> Windows<T> {
    |                +++
 
-error: aborting due to 2 previous errors
+error[E0282]: type annotations needed
+  --> $DIR/issue-109071.rs:11:18
+   |
+LL |     fn next() -> Option<Self::Item> {}
+   |                  ^^^^^^^^^^^^^^^^^^ cannot infer type for type parameter `T`
+
+error[E0282]: type annotations needed
+  --> $DIR/issue-109071.rs:16:15
+   |
+LL |     fn T() -> Option<Self::Item> {}
+   |               ^^^^^^^^^^^^^^^^^^ cannot infer type for type parameter `T`
+
+error: aborting due to 4 previous errors
 
-Some errors have detailed explanations: E0107, E0637.
+Some errors have detailed explanations: E0107, E0282, E0637.
 For more information about an error, try `rustc --explain E0107`.

tests/ui/associated-inherent-types/issue-109299-1.rs

@@ -8,5 +8,6 @@ impl Lexer<i32> {
 }
 
 type X = impl for<T> Fn() -> Lexer<T>::Cursor; //~ ERROR associated type `Cursor` not found for `Lexer<T>` in the current scope
+//~^ ERROR: unconstrained opaque type
 
 fn main() {}

tests/ui/associated-inherent-types/issue-109299-1.stderr

@@ -10,6 +10,14 @@ LL | type X = impl for<T> Fn() -> Lexer<T>::Cursor;
    = note: the associated type was found for
            - `Lexer<i32>`
 
-error: aborting due to previous error
+error: unconstrained opaque type
+  --> $DIR/issue-109299-1.rs:10:10
+   |
+LL | type X = impl for<T> Fn() -> Lexer<T>::Cursor;
+   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: `X` must be used in combination with a concrete type within the same module
+
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0220`.

tests/ui/associated-inherent-types/issue-109768.rs

@@ -8,5 +8,6 @@ impl<T> Local { //~ ERROR missing generics for struct `Local`
     type AssocType3 = T; //~ ERROR inherent associated types are unstable
 
     const WRAPPED_ASSOC_3: Wrapper<Self::AssocType3> = Wrapper();
+    //~^ ERROR: this struct takes 1 argument but 0 arguments were supplied
 }
 //~^ ERROR `main` function not found

tests/ui/associated-inherent-types/issue-109768.stderr

@@ -1,5 +1,5 @@
 error[E0601]: `main` function not found in crate `issue_109768`
-  --> $DIR/issue-109768.rs:11:2
+  --> $DIR/issue-109768.rs:12:2
    |
 LL | }
    |  ^ consider adding a `main` function to `$DIR/issue-109768.rs`
@@ -29,7 +29,23 @@ LL |     type AssocType3 = T;
    = note: see issue #8995 <https://github.com/rust-lang/rust/issues/8995> for more information
    = help: add `#![feature(inherent_associated_types)]` to the crate attributes to enable
 
-error: aborting due to 3 previous errors
+error[E0061]: this struct takes 1 argument but 0 arguments were supplied
+  --> $DIR/issue-109768.rs:10:56
+   |
+LL |     const WRAPPED_ASSOC_3: Wrapper<Self::AssocType3> = Wrapper();
+   |                                                        ^^^^^^^-- an argument is missing
+   |
+note: tuple struct defined here
+  --> $DIR/issue-109768.rs:3:8
+   |
+LL | struct Wrapper<T>(T);
+   |        ^^^^^^^
+help: provide the argument
+   |
+LL |     const WRAPPED_ASSOC_3: Wrapper<Self::AssocType3> = Wrapper(/* value */);
+   |                                                               ~~~~~~~~~~~~~
+
+error: aborting due to 4 previous errors
 
-Some errors have detailed explanations: E0107, E0601, E0658.
-For more information about an error, try `rustc --explain E0107`.
+Some errors have detailed explanations: E0061, E0107, E0601, E0658.
+For more information about an error, try `rustc --explain E0061`.