Auto merge of #39353 - alexcrichton:rollup, r=alexcrichton

Rollup of 21 pull requests

- Successful merges: #38617, #39284, #39285, #39290, #39302, #39305, #39306, #39307, #39311, #39313, #39314, #39321, #39325, #39332, #39335, #39344, #39345, #39346, #39348, #39350, #39351
- Failed merges:

8 files changed, 113 insertions, 11 deletions

diff --git a/src/test/compile-fail/E0117.rs b/src/test/compile-fail/E0117.rs
index e9375e67325..4ba9c3382f3 100644
--- a/src/test/compile-fail/E0117.rs
+++ b/src/test/compile-fail/E0117.rs
@@ -11,6 +11,7 @@
 impl Drop for u32 {} //~ ERROR E0117
 //~^ NOTE impl doesn't use types inside crate
 //~| NOTE the impl does not reference any types defined in this crate
+//~| NOTE define and implement a trait or new type instead
 
 fn main() {
 }
diff --git a/src/test/compile-fail/E0206.rs b/src/test/compile-fail/E0206.rs
index 888e42ed3a1..1131e8e1b01 100644
--- a/src/test/compile-fail/E0206.rs
+++ b/src/test/compile-fail/E0206.rs
@@ -16,6 +16,7 @@ impl Copy for Foo { }
 //~| ERROR only traits defined in the current crate can be implemented for arbitrary types
 //~| NOTE impl doesn't use types inside crate
 //~| NOTE the impl does not reference any types defined in this crate
+//~| NOTE define and implement a trait or new type instead
 
 #[derive(Copy, Clone)]
 struct Bar;
diff --git a/src/test/compile-fail/binary-op-on-double-ref.rs b/src/test/compile-fail/binary-op-on-double-ref.rs
new file mode 100644
index 00000000000..a49cfaa1760
--- /dev/null
+++ b/src/test/compile-fail/binary-op-on-double-ref.rs
@@ -0,0 +1,20 @@
+// Copyright 2012-2016 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.
+
+fn main() {
+    let v = vec![1, 2, 3, 4, 5, 6, 7, 8, 9];
+    let vr = v.iter().filter(|x| {
+        x % 2 == 0
+        //~^ ERROR binary operation `%` cannot be applied to type `&&{integer}`
+        //~| NOTE this is a reference of type that `%` can be applied to
+        //~| NOTE an implementation of `std::ops::Rem` might be missing for `&&{integer}`
+    });
+    println!("{:?}", vr);
+}
diff --git a/src/test/compile-fail/can-begin-expr-check.rs b/src/test/compile-fail/can-begin-expr-check.rs
new file mode 100644
index 00000000000..68f219c6ed9
--- /dev/null
+++ b/src/test/compile-fail/can-begin-expr-check.rs
@@ -0,0 +1,30 @@
+// 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.
+
+pub fn main() {
+
+    return;
+    return ();
+    return as ();
+    return return as ();
+    return return return;
+
+    return if true {
+        ()
+    } else {
+        ()
+    };
+
+    loop {
+        return break as ();
+    }
+
+    return enum; //~ ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `enum`
+}
diff --git a/src/test/compile-fail/coherence-impls-copy.rs b/src/test/compile-fail/coherence-impls-copy.rs
index f686a146042..fe121a3bc48 100644
--- a/src/test/compile-fail/coherence-impls-copy.rs
+++ b/src/test/compile-fail/coherence-impls-copy.rs
@@ -37,6 +37,7 @@ impl Copy for (MyType, MyType) {}
 //~| ERROR only traits defined in the current crate can be implemented for arbitrary types
 //~| NOTE impl doesn't use types inside crate
 //~| NOTE the impl does not reference any types defined in this crate
+//~| NOTE define and implement a trait or new type instead
 
 impl Copy for &'static NotSync {}
 //~^ ERROR the trait `Copy` may not be implemented for this type
@@ -46,8 +47,9 @@ impl Copy for [MyType] {}
 //~^ ERROR the trait `Copy` may not be implemented for this type
 //~| NOTE type is not a structure or enumeration
 //~| ERROR only traits defined in the current crate can be implemented for arbitrary types
-//~| NOTE impl doesn't use types inside crate
 //~| NOTE the impl does not reference any types defined in this crate
+//~| NOTE define and implement a trait or new type instead
+//~| NOTE impl doesn't use types inside crate
 
 impl Copy for &'static [NotSync] {}
 //~^ ERROR the trait `Copy` may not be implemented for this type
@@ -55,6 +57,7 @@ impl Copy for &'static [NotSync] {}
 //~| ERROR only traits defined in the current crate can be implemented for arbitrary types
 //~| NOTE impl doesn't use types inside crate
 //~| NOTE the impl does not reference any types defined in this crate
+//~| NOTE define and implement a trait or new type instead
 
 fn main() {
 }
diff --git a/src/test/compile-fail/uninhabited-reference-type-feature-gated.rs b/src/test/compile-fail/str-concat-on-double-ref.rs
index 8f246eddbcd..f85422f76d4 100644
--- a/src/test/compile-fail/uninhabited-reference-type-feature-gated.rs
+++ b/src/test/compile-fail/str-concat-on-double-ref.rs
@@ -1,4 +1,4 @@
-// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// Copyright 2012-2016 The Rust Project Developers. See the COPYRIGHT
 // file at the top-level directory of this distribution and at
 // http://rust-lang.org/COPYRIGHT.
 //
@@ -8,12 +8,11 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-enum Void {}
-
 fn main() {
-    let x: Result<u32, &'static Void> = Ok(23);
-    let _ = match x {   //~ ERROR non-exhaustive
-        Ok(n) => n,
-    };
+    let a: &String = &"1".to_owned();
+    let b: &str = &"2";
+    let c = a + b;
+    //~^ ERROR binary operation `+` cannot be applied to type `&std::string::String`
+    //~| NOTE an implementation of `std::ops::Add` might be missing for `&std::string::String`
+    println!("{:?}", c);
 }
-
diff --git a/src/test/compile-fail/uninhabited-matches-feature-gated.rs b/src/test/compile-fail/uninhabited-matches-feature-gated.rs
new file mode 100644
index 00000000000..0f8b0a6c238
--- /dev/null
+++ b/src/test/compile-fail/uninhabited-matches-feature-gated.rs
@@ -0,0 +1,50 @@
+// Copyright 2016 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.
+
+#![feature(slice_patterns)]
+
+enum Void {}
+
+fn main() {
+    let x: Result<u32, &'static Void> = Ok(23);
+    let _ = match x {   //~ ERROR non-exhaustive
+        Ok(n) => n,
+    };
+
+    let x: &Void = unsafe { std::mem::uninitialized() };
+    let _ = match x {};
+    //~^ ERROR non-exhaustive
+
+    let x: (Void,) = unsafe { std::mem::uninitialized() };
+    let _ = match x {};
+    //~^ ERROR non-exhaustive
+
+    let x: [Void; 1] = unsafe { std::mem::uninitialized() };
+    let _ = match x {};
+    //~^ ERROR non-exhaustive
+
+    let x: &[Void] = unsafe { std::mem::uninitialized() };
+    let _ = match x {   //~ ERROR non-exhaustive
+        &[] => (),
+    };
+
+    let x: Void = unsafe { std::mem::uninitialized() };
+    let _ = match x {}; // okay
+
+    let x: Result<u32, Void> = Ok(23);
+    let _ = match x {   //~ ERROR non-exhaustive
+        Ok(x) => x,
+    };
+
+    let x: Result<u32, Void> = Ok(23);
+    let Ok(x) = x;
+    //~^ ERROR refutable
+}
+
diff --git a/src/test/run-pass/extern_fat_drop.rs b/src/test/run-pass/extern_fat_drop.rs
index deb7e6bd539..8ce1f744dee 100644
--- a/src/test/run-pass/extern_fat_drop.rs
+++ b/src/test/run-pass/extern_fat_drop.rs
@@ -10,8 +10,6 @@
 
 // aux-build:fat_drop.rs
 
-#![feature(drop_in_place)]
-
 extern crate fat_drop;
 
 fn main() {