Remove unnecessary note

Author: estebank

src/librustc/traits/error_reporting.rs

@@ -769,6 +769,16 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
                                 )
                             };
 
+                        if self.suggest_add_reference_to_arg(
+                            &obligation,
+                            &mut err,
+                            &trait_ref,
+                            points_at_arg,
+                        ) {
+                            self.note_obligation_cause(&mut err, obligation);
+                            err.emit();
+                            return;
+                        }
                         if let Some(ref s) = label {
                             // If it has a custom `#[rustc_on_unimplemented]`
                             // error message, let's display it as the label!
@@ -785,16 +795,6 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
                         self.suggest_borrow_on_unsized_slice(&obligation.cause.code, &mut err);
                         self.suggest_fn_call(&obligation, &mut err, &trait_ref, points_at_arg);
                         self.suggest_remove_reference(&obligation, &mut err, &trait_ref);
-                        if self.suggest_add_reference_to_arg(
-                            &obligation,
-                            &mut err,
-                            &trait_ref,
-                            points_at_arg,
-                        ) {
-                            self.note_obligation_cause(&mut err, obligation);
-                            err.emit();
-                            return;
-                        }
                         self.suggest_semicolon_removal(&obligation, &mut err, span, &trait_ref);
 
                         // Try to report a help message
@@ -1357,7 +1357,6 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
                         // somewhere else in the obligation chain. Do not suggest non-sense.
                         return false;
                     }
-                    err.span.clear_span_labels();
                     err.span_label(span, &format!(
                         "expected an implementor of trait `{}`",
                         obligation.parent_trait_ref.skip_binder(),

src/libsyntax_pos/lib.rs

@@ -735,11 +735,6 @@ impl MultiSpan {
         replacements_occurred
     }
 
-    /// This should be *rarely* used. Remove all the labels in this `MultiSpan`.
-    pub fn clear_span_labels(&mut self) {
-        self.span_labels.clear();
-    }
-
     /// Returns the strings to highlight. We always ensure that there
     /// is an entry for each of the primary spans -- for each primary
     /// span `P`, if there is at least one label with span `P`, we return

src/test/ui/suggestions/issue-62843.stderr

@@ -7,7 +7,6 @@ LL |     println!("{:?}", line.find(pattern));
    |                                expected an implementor of trait `std::str::pattern::Pattern<'_>`
    |                                help: consider borrowing here: `&pattern`
    |
-   = help: the trait `std::ops::FnMut<(char,)>` is not implemented for `std::string::String`
    = note: required because of the requirements on the impl of `std::str::pattern::Pattern<'_>` for `std::string::String`
 
 error: aborting due to previous error

src/test/ui/traits/traits-negative-impls.stderr

@@ -55,7 +55,6 @@ LL |     is_send(Box::new(TestType));
    |             expected an implementor of trait `std::marker::Send`
    |             help: consider borrowing here: `&Box::new(TestType)`
    |
-   = help: the trait `std::marker::Send` is not implemented for `dummy2::TestType`
    = note: required because of the requirements on the impl of `std::marker::Send` for `std::ptr::Unique<dummy2::TestType>`
    = note: required because it appears within the type `std::boxed::Box<dummy2::TestType>`
 
@@ -85,7 +84,6 @@ LL |     is_sync(Outer2(TestType));
    |             expected an implementor of trait `std::marker::Sync`
    |             help: consider borrowing here: `&Outer2(TestType)`
    |
-   = help: the trait `std::marker::Send` is not implemented for `main::TestType`
    = note: required because of the requirements on the impl of `std::marker::Sync` for `Outer2<main::TestType>`
 
 error: aborting due to 7 previous errors