auto merge of #18840 : huonw/rust/tweaks, r=alexcrichton

Fix some old papercuts with diagnostics, e.g. tweaking spans, rewording messages. See individual commits.

src/test/compile-fail/.gitattributes

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

src/test/compile-fail/extern-crate-as-no-string-help.rs

@@ -11,4 +11,5 @@
 // Tests that the proper help is displayed in the error message
 
 extern crate foo as bar;
-//~^ ERROR expected `;`, found `as`; perhaps you meant to enclose the crate name `foo` in a string?
+//~^ ERROR expected `;`, found `as`
+//~^^ HELP perhaps you meant to enclose the crate name `foo` in a string?

src/test/compile-fail/int-literal-too-large-span.rs

@@ -0,0 +1,17 @@
+// 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.
+
+// issue #17123
+
+fn main() {
+    100000000000000000000000000000000 //~ ERROR int literal is too large
+
+        ; // the span shouldn't point to this.
+}

src/test/compile-fail/mod_file_not_exist.rs

@@ -9,6 +9,7 @@
 // except according to those terms.
 
 mod not_a_real_file; //~ ERROR file not found for module `not_a_real_file`
+//~^ HELP name the file either not_a_real_file.rs or not_a_real_file/mod.rs inside the directory
 
 fn main() {
     assert_eq!(mod_file_aux::bar(), 10);

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
+
+}

src/test/run-make/mismatching-target-triples/Makefile

@@ -0,0 +1,11 @@
+-include ../tools.mk
+
+# Issue #10814
+#
+# these are no_std to avoid having to have the standard library or any
+# linkers/assemblers for the relevant platform
+
+all:
+	$(RUSTC) foo.rs --target=i686-unknown-linux-gnu
+	$(RUSTC) bar.rs --target=x86_64-unknown-linux-gnu 2>&1 \
+		| grep "couldn't find crate .foo. with expected target triple x86_64-unknown-linux-gnu"

src/test/run-make/mismatching-target-triples/bar.rs

@@ -0,0 +1,11 @@
+// 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.
+#![no_std]
+extern crate foo;

src/test/run-make/mismatching-target-triples/foo.rs

@@ -0,0 +1,11 @@
+// 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.
+#![no_std]
+#![crate_type = "lib"]