libc::memalign not supported on OSX

[ujh]

On OSX libc doesn't support memalign. It does however support posix_memalign but changing the code to use that instead results in a segfault. I probably just don't know how to use it.

[adamcrume]

Let me know if that segfaults. I don't have an OSX instance handy to test with.

[ujh]

Thank you so much, that seems to work. I can run the tests and there's no segfault. 👍