fixes #698 AppVeyor cannot run -j4
fixes #698 AppVeyor cannot run -j4

thisco-de/nanomsg,featherweight/ftw-kernel-nanomsg,snikulov/nanomsg,reqshark/nanomsg,snikulov/nanomsg,featherweight/ftw-kernel-nanomsg,thisco-de/nanomsg,reqshark/nanomsg,reqshark/nanomsg