From bc258791eb4cc5802c261afc2b923b2875c0736d Mon Sep 17 00:00:00 2001
From: Shantanu Raj <s@sraj.me>
Date: Fri, 5 Aug 2016 17:14:47 +0530
Subject: [PATCH 1/2] Update E0207 to use struct_span_err, add span_label

---
 src/librustc_typeck/collect.rs | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/src/librustc_typeck/collect.rs b/src/librustc_typeck/collect.rs
index 4486748a1f05..dfffe3a4a905 100644
--- a/src/librustc_typeck/collect.rs
+++ b/src/librustc_typeck/collect.rs
@@ -2314,8 +2314,12 @@ fn report_unused_parameter(ccx: &CrateCtxt,
                            kind: &str,
                            name: &str)
 {
-    span_err!(ccx.tcx.sess, span, E0207,
-              "the {} parameter `{}` is not constrained by the \
-               impl trait, self type, or predicates",
-              kind, name);
+    struct_span_err!(
+        ccx.tcx.sess, span, E0207,
+        "the {} parameter `{}` is not constrained by the \
+        impl trait, self type, or predicates",
+        kind, name)
+        .span_label(span, &format!("unconstrained lifetime parameter"))
+        .emit();
+
 }

From 58b618e5270a1bef26ad1ed95820c22e09b24ec5 Mon Sep 17 00:00:00 2001
From: Shantanu Raj <s@sraj.me>
Date: Sat, 6 Aug 2016 00:04:27 +0530
Subject: [PATCH 2/2] Update unit tests to accord for label in E0207

---
 src/test/compile-fail/E0207.rs                         | 1 +
 src/test/compile-fail/impl-unused-rps-in-assoc-type.rs | 1 +
 src/test/compile-fail/issue-22886.rs                   | 1 +
 src/test/compile-fail/issue-35139.rs                   | 1 +
 4 files changed, 4 insertions(+)

diff --git a/src/test/compile-fail/E0207.rs b/src/test/compile-fail/E0207.rs
index bd87dbaf786a..43ff085a4fa8 100644
--- a/src/test/compile-fail/E0207.rs
+++ b/src/test/compile-fail/E0207.rs
@@ -11,6 +11,7 @@
 struct Foo;
 
 impl<T: Default> Foo { //~ ERROR E0207
+                       //~| NOTE unconstrained lifetime parameter
     fn get(&self) -> T {
         <T as Default>::default()
     }
diff --git a/src/test/compile-fail/impl-unused-rps-in-assoc-type.rs b/src/test/compile-fail/impl-unused-rps-in-assoc-type.rs
index 23401db21d89..d48433ee928f 100644
--- a/src/test/compile-fail/impl-unused-rps-in-assoc-type.rs
+++ b/src/test/compile-fail/impl-unused-rps-in-assoc-type.rs
@@ -19,6 +19,7 @@ trait Fun {
 struct Holder { x: String }
 
 impl<'a> Fun for Holder { //~ ERROR E0207
+                          //~| NOTE unconstrained lifetime parameter
     type Output = &'a str;
     fn call<'b>(&'b self) -> &'b str {
         &self.x[..]
diff --git a/src/test/compile-fail/issue-22886.rs b/src/test/compile-fail/issue-22886.rs
index 4aa2571cad0c..d258a4a8b332 100644
--- a/src/test/compile-fail/issue-22886.rs
+++ b/src/test/compile-fail/issue-22886.rs
@@ -21,6 +21,7 @@ fn crash_please() {
 struct Newtype(Option<Box<usize>>);
 
 impl<'a> Iterator for Newtype { //~ ERROR E0207
+                                //~| NOTE unconstrained lifetime parameter
     type Item = &'a Box<usize>;
 
     fn next(&mut self) -> Option<&Box<usize>> {
diff --git a/src/test/compile-fail/issue-35139.rs b/src/test/compile-fail/issue-35139.rs
index 67f0e7aaf971..5c4f161a5004 100644
--- a/src/test/compile-fail/issue-35139.rs
+++ b/src/test/compile-fail/issue-35139.rs
@@ -17,6 +17,7 @@ pub trait MethodType {
 pub struct MTFn;
 
 impl<'a> MethodType for MTFn { //~ ERROR E0207
+                               //~| NOTE unconstrained lifetime parameter
     type GetProp = fmt::Debug + 'a;
 }