fixes compiler warnings about code paths that could dereference a NULL ptr
fixes compiler warnings about code paths that could dereference a NULL ptr

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