Before attempting to port MySQL to other operating systems, check the list of currently supported operating systems first. See https://www.mysql.com/support/supportedplatforms/database.html.
If you create a new port of MySQL, you are free to copy and distribute it under the GPL license, but it does not make you a copyright holder of MySQL.
A working POSIX thread library is needed for the server.
To build MySQL from source, your system must satisfy the tool requirements listed at Installing MySQL from Source.
If you are trying to build MySQL 5.6 with icc on the IA64 platform, and need support for NDB Cluster, you should first ensure that you are using icc version 9.1.043 or later. (For details, see Bug #21875.)
If you run into problems with a new port, you may have to do some debugging of MySQL! See Debugging a MySQL Server.
Before you start debugging mysqld, first get
the test programs
mysys/thr_lock to work. This ensures that
your thread installation has even a remote chance to work!