---

yaml
---
r: 160032
b: refs/heads/try
c: e621e32
h: refs/heads/master
v: v3

Author: huonw

[refs]

@@ -2,7 +2,7 @@
 refs/heads/master: e09d98603e608c9e47d4c89f7b4dca87a4b56da3
 refs/heads/snap-stage1: e33de59e47c5076a89eadeb38f4934f58a3618a6
 refs/heads/snap-stage3: 9c96a79a74f10bed18b031ce0ac4126c56d6cfb3
-refs/heads/try: ceff2ca1fc57d60fa3af2372d49a23055aa441bc
+refs/heads/try: e621e3216bfb074b03ddeb045dc467d9ec4641f8
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/dist-snap: ba4081a5a8573875fed17545846f6f6902c8ba8d
 refs/tags/release-0.2: c870d2dffb391e14efb05aa27898f1f6333a9596

branches/try/src/libsyntax/parse/lexer/mod.rs

@@ -806,6 +806,13 @@ impl<'a> StringReader<'a> {
                                     if ascii_only { "unknown byte escape" }
                                     else { "unknown character escape" },
                                     c);
+                                if e == '\r' {
+                                    let sp = codemap::mk_sp(escaped_pos, last_pos);
+                                    self.span_diagnostic.span_help(
+                                        sp,
+                                        "this is an isolated carriage return; consider checking \
+                                         your editor and version control settings.")
+                                }
                                 false
                             }
                         }

branches/try/src/test/compile-fail/.gitattributes

@@ -0,0 +1 @@
+trailing-carriage-return-in-string.rs -text

branches/try/src/test/compile-fail/trailing-carriage-return-in-string.rs

@@ -0,0 +1,23 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// ignore-tidy-cr
+// Issue #11669
+
+fn main() {
+    // \r\n
+    let ok = "This is \
+ a test";
+    // \r only
+    let bad = "This is \ a test";
+    //~^ ERROR unknown character escape: \r
+    //~^^ HELP this is an isolated carriage return
+
+}