Mash is normally distributed as a dependency-free binary for Linux or OSX (see https://github.com/marbl/Mash/releases). This source distribution is intended for other operating systems or for development. Mash requires c++14 to build, which is available in and GCC >= 5 and XCode >= 6.
See http://mash.readthedocs.org for more information.