some tests failed:
failure: http://buildbot.rust-lang.org/builders/auto-win-32-nopt-t/builds/2603
exception: http://buildbot.rust-lang.org/builders/auto-mac-32-opt/builds/2953
exception: http://buildbot.rust-lang.org/builders/auto-mac-64-opt/builds/2947
exception: http://buildbot.rust-lang.org/builders/auto-mac-64-nopt-t/builds/2948
exception: http://buildbot.rust-lang.org/builders/auto-linux-32-opt/builds/2939
exception: http://buildbot.rust-lang.org/builders/auto-linux-32-nopt-t/builds/2938
exception: http://buildbot.rust-lang.org/builders/auto-linux-64-opt/builds/2941
exception: http://buildbot.rust-lang.org/builders/auto-linux-64-nopt-t/builds/2934
exception: http://buildbot.rust-lang.org/builders/auto-linux-64-x-android-t/builds/2931
exception: http://buildbot.rust-lang.org/builders/auto-win-32-opt/builds/2606
exception: http://buildbot.rust-lang.org/builders/auto-win-64-opt/builds/1442
exception: http://buildbot.rust-lang.org/builders/auto-win-64-nopt-t/builds/1433