Auto merge of #48138 - estebank:issue-45092, r=nikomatsakis

Reword E0044 and message for `!Send` types

 - Reword E0044 help.
 - Change error message for types that don't implement `Send`

CC #45092, #46678, #24909, #33307.

2 files changed, 11 insertions, 10 deletions

diff --git a/src/test/ui/error-codes/E0044.rs b/src/test/ui/error-codes/E0044.rs
index 48fe2300031..35e3c768558 100644
--- a/src/test/ui/error-codes/E0044.rs
+++ b/src/test/ui/error-codes/E0044.rs
@@ -1,4 +1,4 @@
-// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -8,7 +8,12 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-extern { fn some_func<T>(x: T); } //~ ERROR E0044
+extern {
+    fn sqrt<T>(f: T) -> T;
+    //~^ ERROR foreign items may not have type parameters [E0044]
+    //~| HELP use specialization instead of type parameters by replacing them with concrete types
+    //~| NOTE can't have type parameters
+}
 
 fn main() {
 }
diff --git a/src/test/ui/error-codes/E0044.stderr b/src/test/ui/error-codes/E0044.stderr
index b981f525517..ce966251bf4 100644
--- a/src/test/ui/error-codes/E0044.stderr
+++ b/src/test/ui/error-codes/E0044.stderr
@@ -1,14 +1,10 @@
 error[E0044]: foreign items may not have type parameters
-  --> $DIR/E0044.rs:11:10
+  --> $DIR/E0044.rs:12:5
    |
-LL | extern { fn some_func<T>(x: T); } //~ ERROR E0044
-   |          ^^^^^^^^^^^^^^^^^^^^^^
+LL |     fn sqrt<T>(f: T) -> T;
+   |     ^^^^^^^^^^^^^^^^^^^^^^ can't have type parameters
    |
-help: consider using specialization instead of type parameters
-  --> $DIR/E0044.rs:11:10
-   |
-LL | extern { fn some_func<T>(x: T); } //~ ERROR E0044
-   |          ^^^^^^^^^^^^^^^^^^^^^^
+   = help: use specialization instead of type parameters by replacing them with concrete types like `u32`
 
 error: aborting due to previous error