Make is_useful handle empty types properly

1 files changed, 26 insertions, 0 deletions

diff --git a/src/test/compile-fail/match-byte-array-patterns-2.rs b/src/test/compile-fail/match-byte-array-patterns-2.rs
new file mode 100644
index 00000000000..ad7e931a0ec
--- /dev/null
+++ b/src/test/compile-fail/match-byte-array-patterns-2.rs
@@ -0,0 +1,26 @@
+// 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(advanced_slice_patterns, slice_patterns)]
+
+fn main() {
+    let buf = &[0, 1, 2, 3];
+
+    match buf { //~ ERROR non-exhaustive
+        b"AAAA" => {}
+    }
+
+    let buf: &[u8] = buf;
+
+    match buf { //~ ERROR non-exhaustive
+        b"AAAA" => {}
+    }
+}
+