test that a no_builtins crate is passed to the linker

Author: Jorge Aparicio

src/test/run-make/no-builtins-lto/Makefile

@@ -0,0 +1,9 @@
+-include ../tools.mk
+
+all:
+	# Compile a `#![no_builtins]` rlib crate
+	$(RUSTC) no_builtins.rs
+	# Build an executable that depends on that crate using LTO. The no_builtins crate doesn't
+	# participate in LTO, so its rlib must be explicitly linked into the final binary. Verify this by
+	# grepping the linker arguments.
+	$(RUSTC) main.rs -C lto -Z print-link-args | grep 'libno_builtins.rlib'

src/test/run-make/no-builtins-lto/main.rs

@@ -0,0 +1,13 @@
+// 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.
+
+extern crate no_builtins;
+
+fn main() {}

src/test/run-make/no-builtins-lto/no_builtins.rs

@@ -0,0 +1,12 @@
+// 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.
+
+#![crate_type = "lib"]
+#![no_builtins]