Auto merge of #3974 - mcgoo:build_rs_native_path, r=alexcrichton
authorbors <bors@rust-lang.org>
Mon, 8 May 2017 21:11:30 +0000 (21:11 +0000)
committerbors <bors@rust-lang.org>
Mon, 8 May 2017 21:11:30 +0000 (21:11 +0000)
fix dynamic search path for build scripts

fixes https://github.com/rust-lang/cargo/issues/3957


Trivial merge