Further tweak wording of E0759 and introduce E0767

43 files changed, 280 insertions, 167 deletions

diff --git a/src/librustc_error_codes/error_codes.rs b/src/librustc_error_codes/error_codes.rs
index 279c65ce03d..7c762a3415e 100644
--- a/src/librustc_error_codes/error_codes.rs
+++ b/src/librustc_error_codes/error_codes.rs
@@ -633,4 +633,5 @@ E0771: include_str!("./error_codes/E0771.md"),
     E0755, // `#[ffi_pure]` is only allowed on foreign functions
     E0756, // `#[ffi_const]` is only allowed on foreign functions
     E0757, // `#[ffi_const]` functions cannot be `#[ffi_pure]`
+    E0767, // `'static' obligation coming from `impl dyn Trait {}` or `impl Foo for dyn Bar {}`.
 }
diff --git a/src/librustc_infer/infer/error_reporting/nice_region_error/static_impl_trait.rs b/src/librustc_infer/infer/error_reporting/nice_region_error/static_impl_trait.rs
index 36d354ea777..9fa905cb5ab 100644
--- a/src/librustc_infer/infer/error_reporting/nice_region_error/static_impl_trait.rs
+++ b/src/librustc_infer/infer/error_reporting/nice_region_error/static_impl_trait.rs
@@ -45,13 +45,31 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
                     let mut err = struct_span_err!(
                         tcx.sess,
                         cause.span,
-                        E0759,
-                        "cannot infer an appropriate lifetime"
+                        E0767,
+                        "{} has {} but calling `{}` introduces an implicit `'static` lifetime \
+                         requirement",
+                        param
+                            .param
+                            .pat
+                            .simple_ident()
+                            .map(|s| format!("`{}`", s))
+                            .unwrap_or_else(|| "`fn` parameter".to_string()),
+                        lifetime,
+                        assoc.ident,
                     );
                     err.span_label(param.param_ty_span, &format!("this data with {}...", lifetime));
                     err.span_label(
                         cause.span,
-                        "...is captured and required to live as long as `'static` here",
+                        &format!(
+                            "...is captured and required to live as long as `'static` here \
+                             because of an implicit lifetime bound on the {}",
+                            match assoc.container {
+                                AssocItemContainer::TraitContainer(id) =>
+                                    format!("`impl` of `{}`", tcx.def_path_str(id)),
+                                AssocItemContainer::ImplContainer(_) =>
+                                    "inherent `impl`".to_string(),
+                            },
+                        ),
                     );
                     if self.find_impl_on_dyn_trait(&mut err, param.param_ty, assoc) {
                         err.emit();
@@ -78,10 +96,49 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
         } else {
             ("'_".to_owned(), "an anonymous lifetime `'_`".to_string())
         };
-        let mut err = struct_span_err!(tcx.sess, sp, E0759, "cannot infer an appropriate lifetime");
+        let param_name = param
+            .param
+            .pat
+            .simple_ident()
+            .map(|s| format!("`{}`", s))
+            .unwrap_or_else(|| "`fn` parameter".to_string());
+        let mut err = struct_span_err!(
+            tcx.sess,
+            sp,
+            E0759,
+            "{} has {} but it needs to satisfy a `'static` lifetime requirement",
+            param_name,
+            lifetime,
+        );
         err.span_label(param.param_ty_span, &format!("this data with {}...", lifetime));
         debug!("try_report_static_impl_trait: param_info={:?}", param);
 
+        let fn_returns = tcx.return_type_impl_or_dyn_traits(anon_reg_sup.def_id);
+
+        let mut postfix = String::new();
+        if let SubregionOrigin::Subtype(box TypeTrace { cause, .. }) = &sup_origin {
+            if let ObligationCauseCode::UnifyReceiver(assoc) = &cause.code {
+                if self.find_impl_on_dyn_trait(&mut err, param.param_ty, assoc)
+                    && fn_returns.is_empty()
+                {
+                    err.code(rustc_errors::error_code!(E0767));
+                    err.set_primary_message(&format!(
+                        "{} has {} but calling `{}` introduces an implicit `'static` lifetime \
+                         requirement",
+                        param_name, lifetime, assoc.ident,
+                    ));
+                    postfix = format!(
+                        " because of an implicit lifetime on the {}",
+                        match assoc.container {
+                            AssocItemContainer::TraitContainer(id) =>
+                                format!("`impl` of `{}`", tcx.def_path_str(id)),
+                            AssocItemContainer::ImplContainer(_) => "inherent `impl`".to_string(),
+                        },
+                    );
+                }
+            }
+        }
+
         // We try to make the output have fewer overlapping spans if possible.
         if (sp == sup_origin.span() || !return_sp.overlaps(sup_origin.span()))
             && sup_origin.span() != return_sp
@@ -108,36 +165,35 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
                 //    |           ----                               ^
                 err.span_label(
                     sup_origin.span(),
-                    "...is captured here, requiring it to live as long as `'static`",
+                    &format!(
+                        "...is captured here, requiring it to live as long as `'static`{}",
+                        postfix
+                    ),
                 );
             } else {
                 err.span_label(sup_origin.span(), "...is captured here...");
                 if return_sp < sup_origin.span() {
                     err.span_note(
                         return_sp,
-                        "...and is required to live as long as `'static` here",
+                        &format!("...and is required to live as long as `'static` here{}", postfix),
                     );
                 } else {
                     err.span_label(
                         return_sp,
-                        "...and is required to live as long as `'static` here",
+                        &format!("...and is required to live as long as `'static` here{}", postfix),
                     );
                 }
             }
         } else {
             err.span_label(
                 return_sp,
-                "...is captured and required to live as long as `'static` here",
+                &format!(
+                    "...is captured and required to live as long as `'static` here{}",
+                    postfix
+                ),
             );
         }
 
-        if let SubregionOrigin::Subtype(box TypeTrace { cause, .. }) = &sup_origin {
-            if let ObligationCauseCode::UnifyReceiver(assoc) = &cause.code {
-                self.find_impl_on_dyn_trait(&mut err, param.param_ty, assoc);
-            }
-        }
-
-        let fn_returns = tcx.return_type_impl_or_dyn_traits(anon_reg_sup.def_id);
         debug!("try_report_static_impl_trait: fn_return={:?}", fn_returns);
         // FIXME: account for the need of parens in `&(dyn Trait + '_)`
         let consider = "consider changing the";
@@ -295,20 +351,17 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
                             let mut multi_span: MultiSpan = vec![*span].into();
                             multi_span.push_span_label(
                                 *span,
-                                "this trait object has an implicit `'static` lifetime requirement"
-                                    .to_string(),
+                                "this has an implicit `'static` lifetime requirement".to_string(),
                             );
                             multi_span.push_span_label(
                                 assoc.ident.span,
-                                "the `'static` requirement is introduced when calling this method"
+                                "`'static` requirement is introduced when calling this method"
                                     .to_string(),
                             );
                             err.span_note(
                                 multi_span,
                                 &format!(
-                                    "when using method `{}` on `{}`, an implicit `'static` \
-                                     requirement is introduced",
-                                    assoc.ident,
+                                    "`{}`'s inherent `impl` has a `'static` requirement",
                                     tcx.def_path_str(*found_did),
                                 ),
                             );
@@ -363,22 +416,18 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
                     let mut multi_span: MultiSpan = vec![*span].into();
                     multi_span.push_span_label(
                         *span,
-                        "this trait object has an implicit `'static` lifetime requirement"
-                            .to_string(),
+                        "this has an implicit `'static` lifetime requirement".to_string(),
                     );
                     multi_span.push_span_label(
                         method.span,
-                        "the `'static` requirement is introduced when calling this method"
-                            .to_string(),
+                        "`'static` requirement is introduced when calling this method".to_string(),
                     );
                     err.span_note(
                         multi_span,
                         &format!(
-                            "when using method `{}` of trait `{}` on `{}`, an implicit `'static` \
-                             requirement is introduced",
-                            method,
-                            tcx.def_path_str(container_id),
+                            "`{}`'s `impl` of `{}` has an implicit `'static` requirement",
                             tcx.def_path_str(*found_did),
+                            tcx.def_path_str(container_id),
                         ),
                     );
                     err.span_suggestion_verbose(
diff --git a/src/test/ui/associated-types/cache/project-fn-ret-contravariant.transmute.stderr b/src/test/ui/associated-types/cache/project-fn-ret-contravariant.transmute.stderr
index 36812d3c044..0be9b37263a 100644
--- a/src/test/ui/associated-types/cache/project-fn-ret-contravariant.transmute.stderr
+++ b/src/test/ui/associated-types/cache/project-fn-ret-contravariant.transmute.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `x` has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/project-fn-ret-contravariant.rs:38:8
    |
 LL | fn baz<'a,'b>(x: &'a u32) -> &'static u32 {
diff --git a/src/test/ui/associated-types/cache/project-fn-ret-invariant.transmute.stderr b/src/test/ui/associated-types/cache/project-fn-ret-invariant.transmute.stderr
index 9cec0780b3c..0a44864b249 100644
--- a/src/test/ui/associated-types/cache/project-fn-ret-invariant.transmute.stderr
+++ b/src/test/ui/associated-types/cache/project-fn-ret-invariant.transmute.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `x` has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/project-fn-ret-invariant.rs:49:9
    |
 LL | fn baz<'a, 'b>(x: Type<'a>) -> Type<'static> {
diff --git a/src/test/ui/async-await/issues/issue-62097.rs b/src/test/ui/async-await/issues/issue-62097.rs
index ea482d3667e..66ebbd83ffa 100644
--- a/src/test/ui/async-await/issues/issue-62097.rs
+++ b/src/test/ui/async-await/issues/issue-62097.rs
@@ -9,7 +9,7 @@ where
 struct Struct;
 
 impl Struct {
-    pub async fn run_dummy_fn(&self) { //~ ERROR cannot infer
+    pub async fn run_dummy_fn(&self) { //~ ERROR E0759
         foo(|| self.bar()).await;
     }
 
diff --git a/src/test/ui/async-await/issues/issue-62097.stderr b/src/test/ui/async-await/issues/issue-62097.stderr
index 0f58b158904..56a28d904b9 100644
--- a/src/test/ui/async-await/issues/issue-62097.stderr
+++ b/src/test/ui/async-await/issues/issue-62097.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `self` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/issue-62097.rs:12:31
    |
 LL |     pub async fn run_dummy_fn(&self) {
diff --git a/src/test/ui/impl-header-lifetime-elision/dyn-trait.rs b/src/test/ui/impl-header-lifetime-elision/dyn-trait.rs
index d4ad706d01b..89210fdf137 100644
--- a/src/test/ui/impl-header-lifetime-elision/dyn-trait.rs
+++ b/src/test/ui/impl-header-lifetime-elision/dyn-trait.rs
@@ -17,7 +17,7 @@ fn static_val<T: StaticTrait>(_: T) {
 }
 
 fn with_dyn_debug_static<'a>(x: Box<dyn Debug + 'a>) {
-    static_val(x); //~ ERROR cannot infer
+    static_val(x); //~ ERROR E0759
 }
 
 fn not_static_val<T: NotStaticTrait>(_: T) {
diff --git a/src/test/ui/impl-header-lifetime-elision/dyn-trait.stderr b/src/test/ui/impl-header-lifetime-elision/dyn-trait.stderr
index 397cb3750c2..b3bef677d19 100644
--- a/src/test/ui/impl-header-lifetime-elision/dyn-trait.stderr
+++ b/src/test/ui/impl-header-lifetime-elision/dyn-trait.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `x` has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/dyn-trait.rs:20:16
    |
 LL | fn with_dyn_debug_static<'a>(x: Box<dyn Debug + 'a>) {
diff --git a/src/test/ui/impl-trait/must_outlive_least_region_or_bound.nll.stderr b/src/test/ui/impl-trait/must_outlive_least_region_or_bound.nll.stderr
index 3b339c5c3d7..4372de24507 100644
--- a/src/test/ui/impl-trait/must_outlive_least_region_or_bound.nll.stderr
+++ b/src/test/ui/impl-trait/must_outlive_least_region_or_bound.nll.stderr
@@ -12,7 +12,7 @@ LL | fn elided(x: &i32) -> impl Copy + '_ { x }
    |                       ^^^^^^^^^^^^^^
 
 error: lifetime may not live long enough
-  --> $DIR/must_outlive_least_region_or_bound.rs:6:32
+  --> $DIR/must_outlive_least_region_or_bound.rs:5:32
    |
 LL | fn explicit<'a>(x: &'a i32) -> impl Copy { x }
    |             --                 ^^^^^^^^^ opaque type requires that `'a` must outlive `'static`
@@ -26,7 +26,7 @@ LL | fn explicit<'a>(x: &'a i32) -> impl Copy + 'a { x }
    |                                ^^^^^^^^^^^^^^
 
 error: lifetime may not live long enough
-  --> $DIR/must_outlive_least_region_or_bound.rs:9:46
+  --> $DIR/must_outlive_least_region_or_bound.rs:7:46
    |
 LL | fn elided2(x: &i32) -> impl Copy + 'static { x }
    |               -                              ^ returning this value requires that `'1` must outlive `'static`
@@ -36,7 +36,7 @@ LL | fn elided2(x: &i32) -> impl Copy + 'static { x }
    = help: consider replacing `'1` with `'static`
 
 error: lifetime may not live long enough
-  --> $DIR/must_outlive_least_region_or_bound.rs:12:55
+  --> $DIR/must_outlive_least_region_or_bound.rs:9:55
    |
 LL | fn explicit2<'a>(x: &'a i32) -> impl Copy + 'static { x }
    |              -- lifetime `'a` defined here            ^ returning this value requires that `'a` must outlive `'static`
@@ -45,7 +45,7 @@ LL | fn explicit2<'a>(x: &'a i32) -> impl Copy + 'static { x }
    = help: consider replacing `'a` with `'static`
 
 error[E0621]: explicit lifetime required in the type of `x`
-  --> $DIR/must_outlive_least_region_or_bound.rs:15:41
+  --> $DIR/must_outlive_least_region_or_bound.rs:11:41
    |
 LL | fn foo<'a>(x: &i32) -> impl Copy + 'a { x }
    |               ----                      ^ lifetime `'a` required
@@ -53,7 +53,7 @@ LL | fn foo<'a>(x: &i32) -> impl Copy + 'a { x }
    |               help: add explicit lifetime `'a` to the type of `x`: `&'a i32`
 
 error: lifetime may not live long enough
-  --> $DIR/must_outlive_least_region_or_bound.rs:30:24
+  --> $DIR/must_outlive_least_region_or_bound.rs:22:24
    |
 LL | fn elided5(x: &i32) -> (Box<dyn Debug>, impl Debug) { (Box::new(x), x) }
    |               -        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ opaque type requires that `'1` must outlive `'static`
@@ -61,7 +61,7 @@ LL | fn elided5(x: &i32) -> (Box<dyn Debug>, impl Debug) { (Box::new(x), x) }
    |               let's call the lifetime of this reference `'1`
 
 error: lifetime may not live long enough
-  --> $DIR/must_outlive_least_region_or_bound.rs:37:69
+  --> $DIR/must_outlive_least_region_or_bound.rs:28:69
    |
 LL | fn with_bound<'a>(x: &'a i32) -> impl LifetimeTrait<'a> + 'static { x }
    |               -- lifetime `'a` defined here                         ^ returning this value requires that `'a` must outlive `'static`
@@ -70,7 +70,7 @@ LL | fn with_bound<'a>(x: &'a i32) -> impl LifetimeTrait<'a> + 'static { x }
    = help: consider replacing `'a` with `'static`
 
 error: lifetime may not live long enough
-  --> $DIR/must_outlive_least_region_or_bound.rs:42:61
+  --> $DIR/must_outlive_least_region_or_bound.rs:32:61
    |
 LL | fn move_lifetime_into_fn<'a, 'b>(x: &'a u32, y: &'b u32) -> impl Fn(&'a u32) {
    |                          --  -- lifetime `'b` defined here  ^^^^^^^^^^^^^^^^ opaque type requires that `'b` must outlive `'a`
@@ -80,7 +80,7 @@ LL | fn move_lifetime_into_fn<'a, 'b>(x: &'a u32, y: &'b u32) -> impl Fn(&'a u32
    = help: consider adding the following bound: `'b: 'a`
 
 error[E0310]: the parameter type `T` may not live long enough
-  --> $DIR/must_outlive_least_region_or_bound.rs:47:51
+  --> $DIR/must_outlive_least_region_or_bound.rs:37:51
    |
 LL | fn ty_param_wont_outlive_static<T:Debug>(x: T) -> impl Debug + 'static {
    |                                                   ^^^^^^^^^^^^^^^^^^^^
diff --git a/src/test/ui/impl-trait/must_outlive_least_region_or_bound.rs b/src/test/ui/impl-trait/must_outlive_least_region_or_bound.rs
index 9bf86fa66cd..51f488e45a6 100644
--- a/src/test/ui/impl-trait/must_outlive_least_region_or_bound.rs
+++ b/src/test/ui/impl-trait/must_outlive_least_region_or_bound.rs
@@ -1,41 +1,31 @@
 use std::fmt::Debug;
 
-fn elided(x: &i32) -> impl Copy { x }
-//~^ ERROR cannot infer an appropriate lifetime
+fn elided(x: &i32) -> impl Copy { x } //~ ERROR E0759
 
-fn explicit<'a>(x: &'a i32) -> impl Copy { x }
-//~^ ERROR cannot infer an appropriate lifetime
+fn explicit<'a>(x: &'a i32) -> impl Copy { x } //~ ERROR E0759
 
-fn elided2(x: &i32) -> impl Copy + 'static { x }
-//~^ ERROR cannot infer an appropriate lifetime
+fn elided2(x: &i32) -> impl Copy + 'static { x } //~ ERROR E0759
 
-fn explicit2<'a>(x: &'a i32) -> impl Copy + 'static { x }
-//~^ ERROR cannot infer an appropriate lifetime
+fn explicit2<'a>(x: &'a i32) -> impl Copy + 'static { x } //~ ERROR E0759
 
 fn foo<'a>(x: &i32) -> impl Copy + 'a { x }
 //~^ ERROR explicit lifetime required in the type of `x`
 
-fn elided3(x: &i32) -> Box<dyn Debug> { Box::new(x) }
-//~^ ERROR cannot infer an appropriate lifetime
+fn elided3(x: &i32) -> Box<dyn Debug> { Box::new(x) } //~ ERROR E0759
 
-fn explicit3<'a>(x: &'a i32) -> Box<dyn Debug> { Box::new(x) }
-//~^ ERROR cannot infer an appropriate lifetime
+fn explicit3<'a>(x: &'a i32) -> Box<dyn Debug> { Box::new(x) } //~ ERROR E0759
 
-fn elided4(x: &i32) -> Box<dyn Debug + 'static> { Box::new(x) }
-//~^ ERROR cannot infer an appropriate lifetime
+fn elided4(x: &i32) -> Box<dyn Debug + 'static> { Box::new(x) } //~ ERROR E0759
 
-fn explicit4<'a>(x: &'a i32) -> Box<dyn Debug + 'static> { Box::new(x) }
-//~^ ERROR cannot infer an appropriate lifetime
+fn explicit4<'a>(x: &'a i32) -> Box<dyn Debug + 'static> { Box::new(x) } //~ ERROR E0759
 
-fn elided5(x: &i32) -> (Box<dyn Debug>, impl Debug) { (Box::new(x), x) }
-//~^ ERROR cannot infer an appropriate lifetime
-//~| ERROR cannot infer an appropriate lifetime
+fn elided5(x: &i32) -> (Box<dyn Debug>, impl Debug) { (Box::new(x), x) } //~ ERROR E0759
+//~^ ERROR E0759
 
 trait LifetimeTrait<'a> {}
 impl<'a> LifetimeTrait<'a> for &'a i32 {}
 
-fn with_bound<'a>(x: &'a i32) -> impl LifetimeTrait<'a> + 'static { x }
-//~^ ERROR cannot infer an appropriate lifetime
+fn with_bound<'a>(x: &'a i32) -> impl LifetimeTrait<'a> + 'static { x } //~ ERROR E0759
 
 // Tests that a closure type containing 'b cannot be returned from a type where
 // only 'a was expected.
diff --git a/src/test/ui/impl-trait/must_outlive_least_region_or_bound.stderr b/src/test/ui/impl-trait/must_outlive_least_region_or_bound.stderr
index ffadcaae08e..b040889217e 100644
--- a/src/test/ui/impl-trait/must_outlive_least_region_or_bound.stderr
+++ b/src/test/ui/impl-trait/must_outlive_least_region_or_bound.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `x` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/must_outlive_least_region_or_bound.rs:3:35
    |
 LL | fn elided(x: &i32) -> impl Copy { x }
@@ -16,8 +16,8 @@ help: to declare that the `impl Trait` captures data from argument `x`, you can
 LL | fn elided(x: &i32) -> impl Copy + '_ { x }
    |                                 ^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
-  --> $DIR/must_outlive_least_region_or_bound.rs:6:44
+error[E0759]: `x` has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
+  --> $DIR/must_outlive_least_region_or_bound.rs:5:44
    |
 LL | fn explicit<'a>(x: &'a i32) -> impl Copy { x }
    |                    -------                 ^ ...is captured here...
@@ -25,7 +25,7 @@ LL | fn explicit<'a>(x: &'a i32) -> impl Copy { x }
    |                    this data with lifetime `'a`...
    |
 note: ...and is required to live as long as `'static` here
-  --> $DIR/must_outlive_least_region_or_bound.rs:6:32
+  --> $DIR/must_outlive_least_region_or_bound.rs:5:32
    |
 LL | fn explicit<'a>(x: &'a i32) -> impl Copy { x }
    |                                ^^^^^^^^^
@@ -34,8 +34,8 @@ help: to declare that the `impl Trait` captures data from argument `x`, you can
 LL | fn explicit<'a>(x: &'a i32) -> impl Copy + 'a { x }
    |                                          ^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
-  --> $DIR/must_outlive_least_region_or_bound.rs:9:46
+error[E0759]: `x` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
+  --> $DIR/must_outlive_least_region_or_bound.rs:7:46
    |
 LL | fn elided2(x: &i32) -> impl Copy + 'static { x }
    |               ----                           ^ ...is captured here...
@@ -43,7 +43,7 @@ LL | fn elided2(x: &i32) -> impl Copy + 'static { x }
    |               this data with an anonymous lifetime `'_`...
    |
 note: ...and is required to live as long as `'static` here
-  --> $DIR/must_outlive_least_region_or_bound.rs:9:24
+  --> $DIR/must_outlive_least_region_or_bound.rs:7:24
    |
 LL | fn elided2(x: &i32) -> impl Copy + 'static { x }
    |                        ^^^^^^^^^^^^^^^^^^^
@@ -56,8 +56,8 @@ help: alternatively, add an explicit `'static` bound to this reference
 LL | fn elided2(x: &'static i32) -> impl Copy + 'static { x }
    |               ^^^^^^^^^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
-  --> $DIR/must_outlive_least_region_or_bound.rs:12:55
+error[E0759]: `x` has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
+  --> $DIR/must_outlive_least_region_or_bound.rs:9:55
    |
 LL | fn explicit2<'a>(x: &'a i32) -> impl Copy + 'static { x }
    |                     -------                           ^ ...is captured here...
@@ -65,7 +65,7 @@ LL | fn explicit2<'a>(x: &'a i32) -> impl Copy + 'static { x }
    |                     this data with lifetime `'a`...
    |
 note: ...and is required to live as long as `'static` here
-  --> $DIR/must_outlive_least_region_or_bound.rs:12:33
+  --> $DIR/must_outlive_least_region_or_bound.rs:9:33
    |
 LL | fn explicit2<'a>(x: &'a i32) -> impl Copy + 'static { x }
    |                                 ^^^^^^^^^^^^^^^^^^^
@@ -79,15 +79,15 @@ LL | fn explicit2<'a>(x: &'static i32) -> impl Copy + 'static { x }
    |                     ^^^^^^^^^^^^
 
 error[E0621]: explicit lifetime required in the type of `x`
-  --> $DIR/must_outlive_least_region_or_bound.rs:15:24
+  --> $DIR/must_outlive_least_region_or_bound.rs:11:24
    |
 LL | fn foo<'a>(x: &i32) -> impl Copy + 'a { x }
    |               ----     ^^^^^^^^^^^^^^ lifetime `'a` required
    |               |
    |               help: add explicit lifetime `'a` to the type of `x`: `&'a i32`
 
-error[E0759]: cannot infer an appropriate lifetime
-  --> $DIR/must_outlive_least_region_or_bound.rs:30:65
+error[E0759]: `x` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
+  --> $DIR/must_outlive_least_region_or_bound.rs:22:65
    |
 LL | fn elided5(x: &i32) -> (Box<dyn Debug>, impl Debug) { (Box::new(x), x) }
    |               ---- this data with an anonymous lifetime `'_`... ^ ...is captured here, requiring it to live as long as `'static`
@@ -101,14 +101,14 @@ help: to declare that the `impl Trait` captures data from argument `x`, you can
 LL | fn elided5(x: &i32) -> (Box<dyn Debug>, impl Debug + '_) { (Box::new(x), x) }
    |                                                    ^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
-  --> $DIR/must_outlive_least_region_or_bound.rs:30:69
+error[E0759]: `x` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
+  --> $DIR/must_outlive_least_region_or_bound.rs:22:69
    |
 LL | fn elided5(x: &i32) -> (Box<dyn Debug>, impl Debug) { (Box::new(x), x) }
    |               ---- this data with an anonymous lifetime `'_`...     ^ ...is captured here...
    |
 note: ...and is required to live as long as `'static` here
-  --> $DIR/must_outlive_least_region_or_bound.rs:30:41
+  --> $DIR/must_outlive_least_region_or_bound.rs:22:41
    |
 LL | fn elided5(x: &i32) -> (Box<dyn Debug>, impl Debug) { (Box::new(x), x) }
    |                                         ^^^^^^^^^^
@@ -121,14 +121,14 @@ help: to declare that the `impl Trait` captures data from argument `x`, you can
 LL | fn elided5(x: &i32) -> (Box<dyn Debug>, impl Debug + '_) { (Box::new(x), x) }
    |                                                    ^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
-  --> $DIR/must_outlive_least_region_or_bound.rs:37:69
+error[E0759]: `x` has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
+  --> $DIR/must_outlive_least_region_or_bound.rs:28:69
    |
 LL | fn with_bound<'a>(x: &'a i32) -> impl LifetimeTrait<'a> + 'static { x }
    |                      ------- this data with lifetime `'a`...        ^ ...is captured here...
    |
 note: ...and is required to live as long as `'static` here
-  --> $DIR/must_outlive_least_region_or_bound.rs:37:34
+  --> $DIR/must_outlive_least_region_or_bound.rs:28:34
    |
 LL | fn with_bound<'a>(x: &'a i32) -> impl LifetimeTrait<'a> + 'static { x }
    |                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -142,7 +142,7 @@ LL | fn with_bound<'a>(x: &'static i32) -> impl LifetimeTrait<'a> + 'static { x
    |                      ^^^^^^^^^^^^
 
 error[E0623]: lifetime mismatch
-  --> $DIR/must_outlive_least_region_or_bound.rs:42:61
+  --> $DIR/must_outlive_least_region_or_bound.rs:32:61
    |
 LL | fn move_lifetime_into_fn<'a, 'b>(x: &'a u32, y: &'b u32) -> impl Fn(&'a u32) {
    |                                                 -------     ^^^^^^^^^^^^^^^^
@@ -151,15 +151,15 @@ LL | fn move_lifetime_into_fn<'a, 'b>(x: &'a u32, y: &'b u32) -> impl Fn(&'a u32
    |                                                 this parameter and the return type are declared with different lifetimes...
 
 error[E0310]: the parameter type `T` may not live long enough
-  --> $DIR/must_outlive_least_region_or_bound.rs:47:51
+  --> $DIR/must_outlive_least_region_or_bound.rs:37:51
    |
 LL | fn ty_param_wont_outlive_static<T:Debug>(x: T) -> impl Debug + 'static {
    |                                 --                ^^^^^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
    |                                 |
    |                                 help: consider adding an explicit lifetime bound...: `T: 'static +`
 
-error[E0759]: cannot infer an appropriate lifetime
-  --> $DIR/must_outlive_least_region_or_bound.rs:18:50
+error[E0759]: `x` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
+  --> $DIR/must_outlive_least_region_or_bound.rs:14:50
    |
 LL | fn elided3(x: &i32) -> Box<dyn Debug> { Box::new(x) }
    |               ----                               ^ ...is captured here, requiring it to live as long as `'static`
@@ -171,8 +171,8 @@ help: to declare that the trait object captures data from argument `x`, you can
 LL | fn elided3(x: &i32) -> Box<dyn Debug + '_> { Box::new(x) }
    |                                      ^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
-  --> $DIR/must_outlive_least_region_or_bound.rs:21:59
+error[E0759]: `x` has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
+  --> $DIR/must_outlive_least_region_or_bound.rs:16:59
    |
 LL | fn explicit3<'a>(x: &'a i32) -> Box<dyn Debug> { Box::new(x) }
    |                     -------                               ^ ...is captured here, requiring it to live as long as `'static`
@@ -184,8 +184,8 @@ help: to declare that the trait object captures data from argument `x`, you can
 LL | fn explicit3<'a>(x: &'a i32) -> Box<dyn Debug + 'a> { Box::new(x) }
    |                                               ^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
-  --> $DIR/must_outlive_least_region_or_bound.rs:24:60
+error[E0759]: `x` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
+  --> $DIR/must_outlive_least_region_or_bound.rs:18:60
    |
 LL | fn elided4(x: &i32) -> Box<dyn Debug + 'static> { Box::new(x) }
    |               ----                                         ^ ...is captured here, requiring it to live as long as `'static`
@@ -201,8 +201,8 @@ help: alternatively, add an explicit `'static` bound to this reference
 LL | fn elided4(x: &'static i32) -> Box<dyn Debug + 'static> { Box::new(x) }
    |               ^^^^^^^^^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
-  --> $DIR/must_outlive_least_region_or_bound.rs:27:69
+error[E0759]: `x` has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
+  --> $DIR/must_outlive_least_region_or_bound.rs:20:69
    |
 LL | fn explicit4<'a>(x: &'a i32) -> Box<dyn Debug + 'static> { Box::new(x) }
    |                     ------- this data with lifetime `'a`...         ^ ...is captured here, requiring it to live as long as `'static`
diff --git a/src/test/ui/impl-trait/static-return-lifetime-infered.nll.stderr b/src/test/ui/impl-trait/static-return-lifetime-infered.nll.stderr
index 123ea6af6b0..65178cc9d24 100644
--- a/src/test/ui/impl-trait/static-return-lifetime-infered.nll.stderr
+++ b/src/test/ui/impl-trait/static-return-lifetime-infered.nll.stderr
@@ -12,7 +12,7 @@ LL |     fn iter_values_anon(&self) -> impl Iterator<Item=u32> + '_ {
    |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: lifetime may not live long enough
-  --> $DIR/static-return-lifetime-infered.rs:10:37
+  --> $DIR/static-return-lifetime-infered.rs:9:37
    |
 LL |     fn iter_values<'a>(&'a self) -> impl Iterator<Item=u32> {
    |                    --               ^^^^^^^^^^^^^^^^^^^^^^^ opaque type requires that `'a` must outlive `'static`
diff --git a/src/test/ui/impl-trait/static-return-lifetime-infered.rs b/src/test/ui/impl-trait/static-return-lifetime-infered.rs
index 96f3652c226..518c52f5de4 100644
--- a/src/test/ui/impl-trait/static-return-lifetime-infered.rs
+++ b/src/test/ui/impl-trait/static-return-lifetime-infered.rs
@@ -4,13 +4,11 @@ struct A {
 
 impl A {
     fn iter_values_anon(&self) -> impl Iterator<Item=u32> {
-        self.x.iter().map(|a| a.0)
+        self.x.iter().map(|a| a.0) //~ ERROR E0759
     }
-    //~^^ ERROR cannot infer an appropriate lifetime
     fn iter_values<'a>(&'a self) -> impl Iterator<Item=u32> {
-        self.x.iter().map(|a| a.0)
+        self.x.iter().map(|a| a.0) //~ ERROR E0759
     }
-    //~^^ ERROR cannot infer an appropriate lifetime
 }
 
 fn main() {}
diff --git a/src/test/ui/impl-trait/static-return-lifetime-infered.stderr b/src/test/ui/impl-trait/static-return-lifetime-infered.stderr
index df0db6e4fc6..7c289b38822 100644
--- a/src/test/ui/impl-trait/static-return-lifetime-infered.stderr
+++ b/src/test/ui/impl-trait/static-return-lifetime-infered.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `self` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/static-return-lifetime-infered.rs:7:16
    |
 LL |     fn iter_values_anon(&self) -> impl Iterator<Item=u32> {
@@ -18,8 +18,8 @@ help: to declare that the `impl Trait` captures data from argument `self`, you c
 LL |     fn iter_values_anon(&self) -> impl Iterator<Item=u32> + '_ {
    |                                                           ^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
-  --> $DIR/static-return-lifetime-infered.rs:11:16
+error[E0759]: `self` has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
+  --> $DIR/static-return-lifetime-infered.rs:10:16
    |
 LL |     fn iter_values<'a>(&'a self) -> impl Iterator<Item=u32> {
    |                        -------- this data with lifetime `'a`...
@@ -29,7 +29,7 @@ LL |         self.x.iter().map(|a| a.0)
    |         ...is captured here...
    |
 note: ...and is required to live as long as `'static` here
-  --> $DIR/static-return-lifetime-infered.rs:10:37
+  --> $DIR/static-return-lifetime-infered.rs:9:37
    |
 LL |     fn iter_values<'a>(&'a self) -> impl Iterator<Item=u32> {
    |                                     ^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/src/test/ui/issues/issue-16922.rs b/src/test/ui/issues/issue-16922.rs
index 827163ef83c..f048ccd2427 100644
--- a/src/test/ui/issues/issue-16922.rs
+++ b/src/test/ui/issues/issue-16922.rs
@@ -1,8 +1,7 @@
 use std::any::Any;
 
 fn foo<T: Any>(value: &T) -> Box<dyn Any> {
-    Box::new(value) as Box<dyn Any>
-    //~^ ERROR cannot infer an appropriate lifetime
+    Box::new(value) as Box<dyn Any> //~ ERROR E0759
 }
 
 fn main() {
diff --git a/src/test/ui/issues/issue-16922.stderr b/src/test/ui/issues/issue-16922.stderr
index 919594fc9af..6decc751321 100644
--- a/src/test/ui/issues/issue-16922.stderr
+++ b/src/test/ui/issues/issue-16922.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `value` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/issue-16922.rs:4:14
    |
 LL | fn foo<T: Any>(value: &T) -> Box<dyn Any> {
diff --git a/src/test/ui/nll/user-annotations/constant-in-expr-inherent-1.stderr b/src/test/ui/nll/user-annotations/constant-in-expr-inherent-1.stderr
index f823f69c76f..1931934a211 100644
--- a/src/test/ui/nll/user-annotations/constant-in-expr-inherent-1.stderr
+++ b/src/test/ui/nll/user-annotations/constant-in-expr-inherent-1.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `fn` parameter has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/constant-in-expr-inherent-1.rs:8:5
    |
 LL | fn foo<'a>(_: &'a u32) -> &'static u32 {
diff --git a/src/test/ui/object-lifetime/object-lifetime-default-from-box-error.rs b/src/test/ui/object-lifetime/object-lifetime-default-from-box-error.rs
index 708ab1cf382..4a2665d8e16 100644
--- a/src/test/ui/object-lifetime/object-lifetime-default-from-box-error.rs
+++ b/src/test/ui/object-lifetime/object-lifetime-default-from-box-error.rs
@@ -15,7 +15,7 @@ fn load(ss: &mut SomeStruct) -> Box<dyn SomeTrait> {
     // `Box<SomeTrait>` defaults to a `'static` bound, so this return
     // is illegal.
 
-    ss.r //~ ERROR cannot infer an appropriate lifetime
+    ss.r //~ ERROR E0759
 }
 
 fn store(ss: &mut SomeStruct, b: Box<dyn SomeTrait>) {
diff --git a/src/test/ui/object-lifetime/object-lifetime-default-from-box-error.stderr b/src/test/ui/object-lifetime/object-lifetime-default-from-box-error.stderr
index 1b1e0d96107..70b99ef7869 100644
--- a/src/test/ui/object-lifetime/object-lifetime-default-from-box-error.stderr
+++ b/src/test/ui/object-lifetime/object-lifetime-default-from-box-error.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `ss` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/object-lifetime-default-from-box-error.rs:18:5
    |
 LL | fn load(ss: &mut SomeStruct) -> Box<dyn SomeTrait> {
diff --git a/src/test/ui/regions/region-object-lifetime-in-coercion.rs b/src/test/ui/regions/region-object-lifetime-in-coercion.rs
index 5d199149c39..9d3f485e314 100644
--- a/src/test/ui/regions/region-object-lifetime-in-coercion.rs
+++ b/src/test/ui/regions/region-object-lifetime-in-coercion.rs
@@ -5,18 +5,18 @@ trait Foo {}
 impl<'a> Foo for &'a [u8] {}
 
 fn a(v: &[u8]) -> Box<dyn Foo + 'static> {
-    let x: Box<dyn Foo + 'static> = Box::new(v); //~ ERROR cannot infer an appropriate lifetime
+    let x: Box<dyn Foo + 'static> = Box::new(v); //~ ERROR E0759
     x
 }
 
 fn b(v: &[u8]) -> Box<dyn Foo + 'static> {
-    Box::new(v) //~ ERROR cannot infer an appropriate lifetime
+    Box::new(v) //~ ERROR E0759
 }
 
 fn c(v: &[u8]) -> Box<dyn Foo> {
     // same as previous case due to RFC 599
 
-    Box::new(v) //~ ERROR cannot infer an appropriate lifetime
+    Box::new(v) //~ ERROR E0759
 }
 
 fn d<'a,'b>(v: &'a [u8]) -> Box<dyn Foo+'b> {
diff --git a/src/test/ui/regions/region-object-lifetime-in-coercion.stderr b/src/test/ui/regions/region-object-lifetime-in-coercion.stderr
index 7f5a3a47976..63fea1f4162 100644
--- a/src/test/ui/regions/region-object-lifetime-in-coercion.stderr
+++ b/src/test/ui/regions/region-object-lifetime-in-coercion.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `v` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/region-object-lifetime-in-coercion.rs:8:46
    |
 LL | fn a(v: &[u8]) -> Box<dyn Foo + 'static> {
@@ -15,7 +15,7 @@ help: alternatively, add an explicit `'static` bound to this reference
 LL | fn a(v: &'static [u8]) -> Box<dyn Foo + 'static> {
    |         ^^^^^^^^^^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `v` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/region-object-lifetime-in-coercion.rs:13:14
    |
 LL | fn b(v: &[u8]) -> Box<dyn Foo + 'static> {
@@ -32,7 +32,7 @@ help: alternatively, add an explicit `'static` bound to this reference
 LL | fn b(v: &'static [u8]) -> Box<dyn Foo + 'static> {
    |         ^^^^^^^^^^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `v` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/region-object-lifetime-in-coercion.rs:19:14
    |
 LL | fn c(v: &[u8]) -> Box<dyn Foo> {
diff --git a/src/test/ui/regions/regions-addr-of-self.rs b/src/test/ui/regions/regions-addr-of-self.rs
index 647212407fc..4eb1b275f16 100644
--- a/src/test/ui/regions/regions-addr-of-self.rs
+++ b/src/test/ui/regions/regions-addr-of-self.rs
@@ -4,7 +4,7 @@ struct Dog {
 
 impl Dog {
     pub fn chase_cat(&mut self) {
-        let p: &'static mut usize = &mut self.cats_chased; //~ ERROR cannot infer
+        let p: &'static mut usize = &mut self.cats_chased; //~ ERROR E0759
         *p += 1;
     }
 
diff --git a/src/test/ui/regions/regions-addr-of-self.stderr b/src/test/ui/regions/regions-addr-of-self.stderr
index c15a933379c..738691fd695 100644
--- a/src/test/ui/regions/regions-addr-of-self.stderr
+++ b/src/test/ui/regions/regions-addr-of-self.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `self` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/regions-addr-of-self.rs:7:37
    |
 LL |     pub fn chase_cat(&mut self) {
diff --git a/src/test/ui/regions/regions-close-object-into-object-2.rs b/src/test/ui/regions/regions-close-object-into-object-2.rs
index 2364ba27286..7144ab5a24c 100644
--- a/src/test/ui/regions/regions-close-object-into-object-2.rs
+++ b/src/test/ui/regions/regions-close-object-into-object-2.rs
@@ -7,7 +7,7 @@ trait X { }
 impl<'a, T> X for B<'a, T> {}
 
 fn g<'a, T: 'static>(v: Box<dyn A<T> + 'a>) -> Box<dyn X + 'static> {
-    box B(&*v) as Box<dyn X> //~ ERROR cannot infer
+    box B(&*v) as Box<dyn X> //~ ERROR E0759
 }
 
 fn main() { }
diff --git a/src/test/ui/regions/regions-close-object-into-object-2.stderr b/src/test/ui/regions/regions-close-object-into-object-2.stderr
index 114e4052aae..aab7ce993aa 100644
--- a/src/test/ui/regions/regions-close-object-into-object-2.stderr
+++ b/src/test/ui/regions/regions-close-object-into-object-2.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `v` has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/regions-close-object-into-object-2.rs:10:11
    |
 LL | fn g<'a, T: 'static>(v: Box<dyn A<T> + 'a>) -> Box<dyn X + 'static> {
diff --git a/src/test/ui/regions/regions-close-object-into-object-4.rs b/src/test/ui/regions/regions-close-object-into-object-4.rs
index d5310770436..4c087f264f9 100644
--- a/src/test/ui/regions/regions-close-object-into-object-4.rs
+++ b/src/test/ui/regions/regions-close-object-into-object-4.rs
@@ -7,7 +7,7 @@ trait X { }
 impl<'a, T> X for B<'a, T> {}
 
 fn i<'a, T, U>(v: Box<dyn A<U>+'a>) -> Box<dyn X + 'static> {
-    box B(&*v) as Box<dyn X> //~ ERROR cannot infer
+    box B(&*v) as Box<dyn X> //~ ERROR E0759
 }
 
 fn main() {}
diff --git a/src/test/ui/regions/regions-close-object-into-object-4.stderr b/src/test/ui/regions/regions-close-object-into-object-4.stderr
index 850d8194079..90f807a41c5 100644
--- a/src/test/ui/regions/regions-close-object-into-object-4.stderr
+++ b/src/test/ui/regions/regions-close-object-into-object-4.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `v` has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/regions-close-object-into-object-4.rs:10:11
    |
 LL | fn i<'a, T, U>(v: Box<dyn A<U>+'a>) -> Box<dyn X + 'static> {
diff --git a/src/test/ui/regions/regions-proc-bound-capture.rs b/src/test/ui/regions/regions-proc-bound-capture.rs
index 8617c0e9da8..55d964ac534 100644
--- a/src/test/ui/regions/regions-proc-bound-capture.rs
+++ b/src/test/ui/regions/regions-proc-bound-capture.rs
@@ -6,7 +6,7 @@ fn borrowed_proc<'a>(x: &'a isize) -> Box<dyn FnMut()->(isize) + 'a> {
 
 fn static_proc(x: &isize) -> Box<dyn FnMut() -> (isize) + 'static> {
     // This is illegal, because the region bound on `proc` is 'static.
-    Box::new(move || { *x }) //~ ERROR cannot infer an appropriate lifetime
+    Box::new(move || { *x }) //~ ERROR E0759
 }
 
 fn main() { }
diff --git a/src/test/ui/regions/regions-proc-bound-capture.stderr b/src/test/ui/regions/regions-proc-bound-capture.stderr
index 67eee3bb6e2..e76073f4f6b 100644
--- a/src/test/ui/regions/regions-proc-bound-capture.stderr
+++ b/src/test/ui/regions/regions-proc-bound-capture.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `x` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/regions-proc-bound-capture.rs:9:14
    |
 LL | fn static_proc(x: &isize) -> Box<dyn FnMut() -> (isize) + 'static> {
diff --git a/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait-async.rs b/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait-async.rs
index 0afe631f1e3..43998ca8c57 100644
--- a/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait-async.rs
+++ b/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait-async.rs
@@ -6,7 +6,7 @@ struct Foo;
 
 impl Foo {
     async fn f(self: Pin<&Self>) -> impl Clone { self }
-    //~^ ERROR cannot infer an appropriate lifetime
+    //~^ ERROR E0759
 }
 
 fn main() {
diff --git a/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait-async.stderr b/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait-async.stderr
index f2fbb0ba7d7..9cd0fd328ff 100644
--- a/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait-async.stderr
+++ b/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait-async.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `self` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/arbitrary_self_types_pin_lifetime_impl_trait-async.rs:8:16
    |
 LL |     async fn f(self: Pin<&Self>) -> impl Clone { self }
diff --git a/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait.rs b/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait.rs
index 5054568b189..04935fc52ab 100644
--- a/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait.rs
+++ b/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait.rs
@@ -3,7 +3,7 @@ use std::pin::Pin;
 struct Foo;
 
 impl Foo {
-    fn f(self: Pin<&Self>) -> impl Clone { self } //~ ERROR cannot infer an appropriate lifetime
+    fn f(self: Pin<&Self>) -> impl Clone { self } //~ ERROR E0759
 }
 
 fn main() {
diff --git a/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait.stderr b/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait.stderr
index 2e10ab3d3f9..cb9d5b56dbc 100644
--- a/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait.stderr
+++ b/src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `self` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/arbitrary_self_types_pin_lifetime_impl_trait.rs:6:44
    |
 LL |     fn f(self: Pin<&Self>) -> impl Clone { self }
diff --git a/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.fixed b/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.fixed
index 62cf9b989bb..832b185e619 100644
--- a/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.fixed
+++ b/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.fixed
@@ -17,7 +17,7 @@ mod foo {
     impl Irrelevant for dyn ObjectTrait {}
 
     fn use_it<'a>(val: &'a dyn ObjectTrait) -> impl OtherTrait<'a> + 'a {
-        val.use_self() //~ ERROR cannot infer an appropriate lifetime
+        val.use_self() //~ ERROR E0759
     }
 }
 
@@ -34,7 +34,7 @@ mod bar {
     impl Irrelevant for dyn ObjectTrait {}
 
     fn use_it<'a>(val: &'a dyn ObjectTrait) -> &'a () {
-        val.use_self() //~ ERROR cannot infer an appropriate lifetime
+        val.use_self() //~ ERROR E0767
     }
 }
 
@@ -51,7 +51,7 @@ mod baz {
     impl Irrelevant for Box<dyn ObjectTrait> {}
 
     fn use_it<'a>(val: &'a Box<dyn ObjectTrait + 'a>) -> &'a () {
-        val.use_self() //~ ERROR cannot infer an appropriate lifetime
+        val.use_self() //~ ERROR E0767
     }
 }
 
@@ -66,8 +66,29 @@ mod bat {
     }
 
     fn use_it<'a>(val: &'a dyn ObjectTrait) -> impl OtherTrait<'a> + 'a {
-        val.use_self() //~ ERROR cannot infer an appropriate lifetime
+        val.use_self() //~ ERROR E0767
     }
 }
 
+mod ban {
+    trait OtherTrait<'a> {}
+    impl<'a> OtherTrait<'a> for &'a () {}
+
+    trait ObjectTrait {}
+    trait MyTrait {
+        fn use_self(&self) -> &();
+    }
+    trait Irrelevant {}
+
+    impl MyTrait for dyn ObjectTrait + '_ {
+        fn use_self(&self) -> &() { panic!() }
+    }
+    impl Irrelevant for dyn ObjectTrait {}
+
+    fn use_it<'a>(val: &'a dyn ObjectTrait) -> impl OtherTrait<'a> + 'a {
+        val.use_self() //~ ERROR E0759
+    }
+}
+
+
 fn main() {}
diff --git a/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.nll.stderr b/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.nll.stderr
index 00f65a23489..8765591c4a1 100644
--- a/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.nll.stderr
+++ b/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.nll.stderr
@@ -18,5 +18,15 @@ LL |         val.use_self()
    |
    = help: consider replacing `'a` with `'static`
 
-error: aborting due to 2 previous errors
+error[E0521]: borrowed data escapes outside of function
+  --> $DIR/impl-on-dyn-trait-with-implicit-static-bound.rs:89:9
+   |
+LL |     fn use_it<'a>(val: &'a dyn ObjectTrait) -> impl OtherTrait<'a> {
+   |                   --- `val` is a reference that is only valid in the function body
+LL |         val.use_self()
+   |         ^^^^^^^^^^^^^^ `val` escapes the function body here
+   |
+   = help: consider replacing `'a` with `'static`
+
+error: aborting due to 3 previous errors
 
diff --git a/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.rs b/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.rs
index 28a599d12bf..ba26c2d67df 100644
--- a/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.rs
+++ b/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.rs
@@ -17,7 +17,7 @@ mod foo {
     impl Irrelevant for dyn ObjectTrait {}
 
     fn use_it<'a>(val: &'a dyn ObjectTrait) -> impl OtherTrait<'a> + 'a {
-        val.use_self() //~ ERROR cannot infer an appropriate lifetime
+        val.use_self() //~ ERROR E0759
     }
 }
 
@@ -34,7 +34,7 @@ mod bar {
     impl Irrelevant for dyn ObjectTrait {}
 
     fn use_it<'a>(val: &'a dyn ObjectTrait) -> &'a () {
-        val.use_self() //~ ERROR cannot infer an appropriate lifetime
+        val.use_self() //~ ERROR E0767
     }
 }
 
@@ -51,7 +51,7 @@ mod baz {
     impl Irrelevant for Box<dyn ObjectTrait> {}
 
     fn use_it<'a>(val: &'a Box<dyn ObjectTrait + 'a>) -> &'a () {
-        val.use_self() //~ ERROR cannot infer an appropriate lifetime
+        val.use_self() //~ ERROR E0767
     }
 }
 
@@ -66,8 +66,29 @@ mod bat {
     }
 
     fn use_it<'a>(val: &'a dyn ObjectTrait) -> impl OtherTrait<'a> + 'a {
-        val.use_self() //~ ERROR cannot infer an appropriate lifetime
+        val.use_self() //~ ERROR E0767
     }
 }
 
+mod ban {
+    trait OtherTrait<'a> {}
+    impl<'a> OtherTrait<'a> for &'a () {}
+
+    trait ObjectTrait {}
+    trait MyTrait {
+        fn use_self(&self) -> &();
+    }
+    trait Irrelevant {}
+
+    impl MyTrait for dyn ObjectTrait {
+        fn use_self(&self) -> &() { panic!() }
+    }
+    impl Irrelevant for dyn ObjectTrait {}
+
+    fn use_it<'a>(val: &'a dyn ObjectTrait) -> impl OtherTrait<'a> {
+        val.use_self() //~ ERROR E0759
+    }
+}
+
+
 fn main() {}
diff --git a/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.stderr b/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.stderr
index 8f8fd9dc324..425159edbcd 100644
--- a/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.stderr
+++ b/src/test/ui/suggestions/impl-on-dyn-trait-with-implicit-static-bound.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `val` has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/impl-on-dyn-trait-with-implicit-static-bound.rs:20:13
    |
 LL |     fn use_it<'a>(val: &'a dyn ObjectTrait) -> impl OtherTrait<'a> + 'a {
@@ -6,78 +6,102 @@ LL |     fn use_it<'a>(val: &'a dyn ObjectTrait) -> impl OtherTrait<'a> + 'a {
 LL |         val.use_self()
    |             ^^^^^^^^ ...is captured and required to live as long as `'static` here
    |
-note: when using method `use_self` of trait `foo::MyTrait` on `foo::ObjectTrait`, an implicit `'static` requirement is introduced
+note: `foo::ObjectTrait`'s `impl` of `foo::MyTrait` has an implicit `'static` requirement
   --> $DIR/impl-on-dyn-trait-with-implicit-static-bound.rs:14:26
    |
 LL |     impl MyTrait for dyn ObjectTrait {
-   |                          ^^^^^^^^^^^ this trait object has an implicit `'static` lifetime requirement
+   |                          ^^^^^^^^^^^ this has an implicit `'static` lifetime requirement
 LL |         fn use_self(&self) -> &() { panic!() }
-   |            -------- the `'static` requirement is introduced when calling this method
+   |            -------- `'static` requirement is introduced when calling this method
 help: consider relaxing the implicit `'static` requirement
    |
 LL |     impl MyTrait for dyn ObjectTrait + '_ {
    |                                      ^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
+error[E0767]: `val` has lifetime `'a` but calling `use_self` introduces an implicit `'static` lifetime requirement
   --> $DIR/impl-on-dyn-trait-with-implicit-static-bound.rs:69:13
    |
 LL |     fn use_it<'a>(val: &'a dyn ObjectTrait) -> impl OtherTrait<'a> + 'a {
    |                        ------------------- this data with lifetime `'a`...
 LL |         val.use_self()
-   |             ^^^^^^^^ ...is captured and required to live as long as `'static` here
+   |             ^^^^^^^^ ...is captured and required to live as long as `'static` here because of an implicit lifetime bound on the inherent `impl`
    |
-note: when using method `use_self` on `bat::ObjectTrait`, an implicit `'static` requirement is introduced
+note: `bat::ObjectTrait`'s inherent `impl` has a `'static` requirement
   --> $DIR/impl-on-dyn-trait-with-implicit-static-bound.rs:64:14
    |
 LL |     impl dyn ObjectTrait {
-   |              ^^^^^^^^^^^ this trait object has an implicit `'static` lifetime requirement
+   |              ^^^^^^^^^^^ this has an implicit `'static` lifetime requirement
 LL |         fn use_self(&self) -> &() { panic!() }
-   |            -------- the `'static` requirement is introduced when calling this method
+   |            -------- `'static` requirement is introduced when calling this method
 help: consider relaxing the implicit `'static` requirement
    |
 LL |     impl dyn ObjectTrait + '_ {
    |                          ^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `val` has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
+  --> $DIR/impl-on-dyn-trait-with-implicit-static-bound.rs:89:13
+   |
+LL |     fn use_it<'a>(val: &'a dyn ObjectTrait) -> impl OtherTrait<'a> {
+   |                        ------------------- this data with lifetime `'a`...
+LL |         val.use_self()
+   |             ^^^^^^^^ ...is captured and required to live as long as `'static` here
+   |
+note: `ban::ObjectTrait`'s `impl` of `ban::MyTrait` has an implicit `'static` requirement
+  --> $DIR/impl-on-dyn-trait-with-implicit-static-bound.rs:83:26
+   |
+LL |     impl MyTrait for dyn ObjectTrait {
+   |                          ^^^^^^^^^^^ this has an implicit `'static` lifetime requirement
+LL |         fn use_self(&self) -> &() { panic!() }
+   |            -------- `'static` requirement is introduced when calling this method
+help: consider relaxing the implicit `'static` requirement
+   |
+LL |     impl MyTrait for dyn ObjectTrait + '_ {
+   |                                      ^^^^
+help: to declare that the `impl Trait` captures data from argument `val`, you can add an explicit `'a` lifetime bound
+   |
+LL |     fn use_it<'a>(val: &'a dyn ObjectTrait) -> impl OtherTrait<'a> + 'a {
+   |                                                                    ^^^^
+
+error[E0767]: `val` has lifetime `'a` but calling `use_self` introduces an implicit `'static` lifetime requirement
   --> $DIR/impl-on-dyn-trait-with-implicit-static-bound.rs:37:13
    |
 LL |     fn use_it<'a>(val: &'a dyn ObjectTrait) -> &'a () {
    |                        ------------------- this data with lifetime `'a`...
 LL |         val.use_self()
-   |             ^^^^^^^^ ...is captured and required to live as long as `'static` here
+   |             ^^^^^^^^ ...is captured and required to live as long as `'static` here because of an implicit lifetime on the `impl` of `bar::MyTrait`
    |
-note: when using method `use_self` of trait `bar::MyTrait` on `bar::ObjectTrait`, an implicit `'static` requirement is introduced
+note: `bar::ObjectTrait`'s `impl` of `bar::MyTrait` has an implicit `'static` requirement
   --> $DIR/impl-on-dyn-trait-with-implicit-static-bound.rs:31:26
    |
 LL |     impl MyTrait for dyn ObjectTrait {
-   |                          ^^^^^^^^^^^ this trait object has an implicit `'static` lifetime requirement
+   |                          ^^^^^^^^^^^ this has an implicit `'static` lifetime requirement
 LL |         fn use_self(&self) -> &() { panic!() }
-   |            -------- the `'static` requirement is introduced when calling this method
+   |            -------- `'static` requirement is introduced when calling this method
 help: consider relaxing the implicit `'static` requirement
    |
 LL |     impl MyTrait for dyn ObjectTrait + '_ {
    |                                      ^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
+error[E0767]: `val` has lifetime `'a` but calling `use_self` introduces an implicit `'static` lifetime requirement
   --> $DIR/impl-on-dyn-trait-with-implicit-static-bound.rs:54:13
    |
 LL |     fn use_it<'a>(val: &'a Box<dyn ObjectTrait + 'a>) -> &'a () {
    |                        ----------------------------- this data with lifetime `'a`...
 LL |         val.use_self()
-   |             ^^^^^^^^ ...is captured and required to live as long as `'static` here
+   |             ^^^^^^^^ ...is captured and required to live as long as `'static` here because of an implicit lifetime on the `impl` of `baz::MyTrait`
    |
-note: when using method `use_self` of trait `baz::MyTrait` on `baz::ObjectTrait`, an implicit `'static` requirement is introduced
+note: `baz::ObjectTrait`'s `impl` of `baz::MyTrait` has an implicit `'static` requirement
   --> $DIR/impl-on-dyn-trait-with-implicit-static-bound.rs:48:30
    |
 LL |     impl MyTrait for Box<dyn ObjectTrait> {
-   |                              ^^^^^^^^^^^ this trait object has an implicit `'static` lifetime requirement
+   |                              ^^^^^^^^^^^ this has an implicit `'static` lifetime requirement
 LL |         fn use_self(&self) -> &() { panic!() }
-   |            -------- the `'static` requirement is introduced when calling this method
+   |            -------- `'static` requirement is introduced when calling this method
 help: consider relaxing the implicit `'static` requirement
    |
 LL |     impl MyTrait for Box<dyn ObjectTrait + '_> {
    |                                          ^^^^
 
-error: aborting due to 4 previous errors
+error: aborting due to 5 previous errors
 
 For more information about this error, try `rustc --explain E0759`.
diff --git a/src/test/ui/suggestions/lifetimes/missing-lifetimes-in-signature.rs b/src/test/ui/suggestions/lifetimes/missing-lifetimes-in-signature.rs
index d3853445dfd..94dd826a15c 100644
--- a/src/test/ui/suggestions/lifetimes/missing-lifetimes-in-signature.rs
+++ b/src/test/ui/suggestions/lifetimes/missing-lifetimes-in-signature.rs
@@ -16,7 +16,7 @@ fn foo<G, T>(g: G, dest: &mut T) -> impl FnOnce()
 where
     G: Get<T>
 {
-    move || { //~ ERROR cannot infer an appropriate lifetime
+    move || { //~ ERROR `dest`
         *dest = g.get();
     }
 }
diff --git a/src/test/ui/suggestions/lifetimes/missing-lifetimes-in-signature.stderr b/src/test/ui/suggestions/lifetimes/missing-lifetimes-in-signature.stderr
index 9ab06032853..d7051515f11 100644
--- a/src/test/ui/suggestions/lifetimes/missing-lifetimes-in-signature.stderr
+++ b/src/test/ui/suggestions/lifetimes/missing-lifetimes-in-signature.stderr
@@ -6,7 +6,7 @@ LL | fn baz<G: 'a, T>(g: G, dest: &mut T) -> impl FnOnce() + '_
    |        |
    |        help: consider introducing lifetime `'a` here: `'a,`
 
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `dest` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/missing-lifetimes-in-signature.rs:19:5
    |
 LL |   fn foo<G, T>(g: G, dest: &mut T) -> impl FnOnce()
diff --git a/src/test/ui/suggestions/lifetimes/trait-object-nested-in-impl-trait.rs b/src/test/ui/suggestions/lifetimes/trait-object-nested-in-impl-trait.rs
index f78edb1c83a..d8446e58dbb 100644
--- a/src/test/ui/suggestions/lifetimes/trait-object-nested-in-impl-trait.rs
+++ b/src/test/ui/suggestions/lifetimes/trait-object-nested-in-impl-trait.rs
@@ -27,7 +27,7 @@ impl Bar {
     fn iter(&self) -> impl Iterator<Item = Box<dyn Foo>> {
         Iter {
             current: None,
-            remaining: self.0.iter(), //~ ERROR cannot infer an appropriate lifetime
+            remaining: self.0.iter(), //~ ERROR E0759
         }
     }
 }
@@ -38,7 +38,7 @@ impl Baz {
     fn iter(&self) -> impl Iterator<Item = Box<dyn Foo>> + '_ {
         Iter {
             current: None,
-            remaining: self.0.iter(), //~ ERROR cannot infer an appropriate lifetime
+            remaining: self.0.iter(), //~ ERROR E0759
         }
     }
 }
@@ -49,7 +49,7 @@ impl Bat {
     fn iter<'a>(&'a self) -> impl Iterator<Item = Box<dyn Foo>> + 'a {
         Iter {
             current: None,
-            remaining: self.0.iter(), //~ ERROR cannot infer an appropriate lifetime
+            remaining: self.0.iter(), //~ ERROR E0759
         }
     }
 }
@@ -60,7 +60,7 @@ impl Ban {
     fn iter<'a>(&'a self) -> impl Iterator<Item = Box<dyn Foo>> {
         Iter {
             current: None,
-            remaining: self.0.iter(), //~ ERROR cannot infer an appropriate lifetime
+            remaining: self.0.iter(), //~ ERROR E0759
         }
     }
 }
diff --git a/src/test/ui/suggestions/lifetimes/trait-object-nested-in-impl-trait.stderr b/src/test/ui/suggestions/lifetimes/trait-object-nested-in-impl-trait.stderr
index 1257e9b172c..9f30787f07c 100644
--- a/src/test/ui/suggestions/lifetimes/trait-object-nested-in-impl-trait.stderr
+++ b/src/test/ui/suggestions/lifetimes/trait-object-nested-in-impl-trait.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `self` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/trait-object-nested-in-impl-trait.rs:30:31
    |
 LL |     fn iter(&self) -> impl Iterator<Item = Box<dyn Foo>> {
@@ -23,7 +23,7 @@ help: to declare that the trait object captures data from argument `self`, you c
 LL |     fn iter(&self) -> impl Iterator<Item = Box<dyn Foo + '_>> {
    |                                                        ^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `self` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/trait-object-nested-in-impl-trait.rs:41:31
    |
 LL |     fn iter(&self) -> impl Iterator<Item = Box<dyn Foo>> + '_ {
@@ -44,7 +44,7 @@ help: to declare that the trait object captures data from argument `self`, you c
 LL |     fn iter(&self) -> impl Iterator<Item = Box<dyn Foo + '_>> + '_ {
    |                                                        ^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `self` has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/trait-object-nested-in-impl-trait.rs:52:31
    |
 LL |     fn iter<'a>(&'a self) -> impl Iterator<Item = Box<dyn Foo>> + 'a {
@@ -65,7 +65,7 @@ help: to declare that the trait object captures data from argument `self`, you c
 LL |     fn iter<'a>(&'a self) -> impl Iterator<Item = Box<dyn Foo + 'a>> + 'a {
    |                                                               ^^^^
 
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `self` has lifetime `'a` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/trait-object-nested-in-impl-trait.rs:63:31
    |
 LL |     fn iter<'a>(&'a self) -> impl Iterator<Item = Box<dyn Foo>> {
diff --git a/src/test/ui/underscore-lifetime/dyn-trait-underscore.rs b/src/test/ui/underscore-lifetime/dyn-trait-underscore.rs
index d5aa18eb0f4..e951adf030f 100644
--- a/src/test/ui/underscore-lifetime/dyn-trait-underscore.rs
+++ b/src/test/ui/underscore-lifetime/dyn-trait-underscore.rs
@@ -5,7 +5,7 @@
 
 fn a<T>(items: &[T]) -> Box<dyn Iterator<Item=&T>> {
     //                      ^^^^^^^^^^^^^^^^^^^^^ bound *here* defaults to `'static`
-    Box::new(items.iter()) //~ ERROR cannot infer an appropriate lifetime
+    Box::new(items.iter()) //~ ERROR E0759
 }
 
 fn b<T>(items: &[T]) -> Box<dyn Iterator<Item=&T> + '_> {
diff --git a/src/test/ui/underscore-lifetime/dyn-trait-underscore.stderr b/src/test/ui/underscore-lifetime/dyn-trait-underscore.stderr
index dda5de431d3..dd804864dab 100644
--- a/src/test/ui/underscore-lifetime/dyn-trait-underscore.stderr
+++ b/src/test/ui/underscore-lifetime/dyn-trait-underscore.stderr
@@ -1,4 +1,4 @@
-error[E0759]: cannot infer an appropriate lifetime
+error[E0759]: `items` has an anonymous lifetime `'_` but it needs to satisfy a `'static` lifetime requirement
   --> $DIR/dyn-trait-underscore.rs:8:20
    |
 LL | fn a<T>(items: &[T]) -> Box<dyn Iterator<Item=&T>> {