some tests failed:
failure: http://buildbot.rust-lang.org/builders/auto-mac-64-nopt-t/builds/2959
exception: http://buildbot.rust-lang.org/builders/auto-mac-32-opt/builds/2964
exception: http://buildbot.rust-lang.org/builders/auto-mac-64-opt/builds/2958
exception: http://buildbot.rust-lang.org/builders/auto-linux-32-opt/builds/2950
exception: http://buildbot.rust-lang.org/builders/auto-linux-32-nopt-t/builds/2949
exception: http://buildbot.rust-lang.org/builders/auto-linux-64-opt/builds/2952
exception: http://buildbot.rust-lang.org/builders/auto-linux-64-nopt-t/builds/2945
exception: http://buildbot.rust-lang.org/builders/auto-linux-64-x-android-t/builds/2942
exception: http://buildbot.rust-lang.org/builders/auto-win-32-opt/builds/2617
exception: http://buildbot.rust-lang.org/builders/auto-win-32-nopt-t/builds/2614
exception: http://buildbot.rust-lang.org/builders/auto-win-64-opt/builds/1453
exception: http://buildbot.rust-lang.org/builders/auto-win-64-nopt-t/builds/1444