auto merge of #18015 : jakub-/rust/issue-4201, r=pcwalton

Closes #4201.

src/test/compile-fail/if-without-else-result.rs

@@ -8,11 +8,10 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// error-pattern:mismatched types: expected `()`, found `bool`
-
 extern crate debug;
 
 fn main() {
     let a = if true { true };
+//~^ ERROR if may be missing an else clause: expected `()`, found `bool` (expected (), found bool)
     println!("{:?}", a);
 }

src/test/compile-fail/issue-4201.rs

@@ -0,0 +1,18 @@
+// 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.
+
+fn main() {
+    let a = if true {
+        0
+    } else if false {
+//~^ ERROR if may be missing an else clause: expected `()`, found `<generic integer #1>`
+        1
+    };
+}