auto merge of #17678 : fhahn/rust/issue-17628-infinite-recursion, r=alexcrichton

This is a patch for #17628, thanks to @kmcallister for your helpful hints!

src/test/compile-fail/infinite-macro-expansion.rs

@@ -0,0 +1,22 @@
+// 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.
+
+#![feature(macro_rules)]
+
+macro_rules! recursive(
+      () => (
+                recursive!() //~ ERROR Recursion limit reached while expanding the macro `recursive`
+              )
+      )
+
+fn main() {
+    recursive!()
+}
+