Add "_aligned_malloc" on windows platform

[paddyhoran]

Hi,

I'm trying to add windows support for a another library which uses posix_memalign. I have researched to the point of realizing that I need libc to expose _aligned_malloc for windows.

I'm willing to have a go at a PR to add it but I'm a little out of my depth...

Could someone more knowledgeable point my in the direction of a similar function already implemented in libc and I will try to have a go adding this one.

Obviously, any other advise is welcome.

Thanks

[gnzlbg]

@paddyhoran I can mentor your with your PR, just take a look at the windows.rs module: https://github.com/rust-lang/libc/blob/master/src/windows.rs#L201 You just need to add an extern function for it there. You can find its API here: https://msdn.microsoft.com/en-us/library/8z34s9c6.aspx

[paddyhoran]

Thanks @gnzlbg, I'll submit a PR when I get a chance.

[retep998]

Keep in mind that aligned_malloc is not the same as posix_memalign as memory allocated using posix_memalign can be freed using free but _aligned_malloc memory has to be deallocated specifically using _aligned_free.