Fix ICE for unexpected < in pattern

src/libsyntax/parse/parser.rs

@@ -3496,6 +3496,9 @@ impl<'a> Parser<'a> {
                     };
                     pat = PatIdent(BindByValue(MutImmutable), pth1, sub);
                 }
+            } else if self.look_ahead(1, |t| *t == token::Lt) {
+                self.bump();
+                self.unexpected()
             } else {
                 // parse an enum pat
                 let enum_path = self.parse_path(LifetimeAndTypesWithColons);

src/test/compile-fail/issue-22426-1.rs

@@ -0,0 +1,17 @@
+// Copyright 2015 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() {
+  match 42 {
+    x < 7 => (),
+   //~^ error: unexpected token: `<`
+    _ => ()
+  }
+}

src/test/compile-fail/issue-22426-2.rs

@@ -0,0 +1,12 @@
+// Copyright 2015 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 a(B<) {}
+   //~^ error: unexpected token: `<`

src/test/compile-fail/issue-22426-3.rs

@@ -0,0 +1,22 @@
+// Copyright 2015 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.
+
+struct Foo<T>(T, T);
+
+impl<T> Foo<T> {
+    fn foo(&self) {
+        match *self {
+            Foo<T>(x, y) => {
+            //~^ error: unexpected token: `<`
+              println!("Goodbye, World!")
+            }
+        }
+    }
+}

src/test/run-pass/issue-22426.rs

@@ -0,0 +1,28 @@
+// Copyright 2015 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.
+
+struct Foo<T>(T, T);
+
+impl<T> Foo<T> {
+    fn foo(&self) {
+        match *self {
+            Foo::<T>(ref x, ref y) => {
+              println!("Goodbye, World!")
+            }
+        }
+    }
+}
+
+fn main() {
+  match 42 {
+    x if x < 7 => (),
+    _ => ()
+  }
+}