Fix linking errors with floorl on MSVC by including math.h in a .cpp file. floorl is a force inline function defined in a header thus not visible for the linker.
Fix linking errors with floorl on MSVC by including math.h in a .cpp file. floorl is a force inline function defined in a header thus not visible for the linker.

andrewrk/zig,andrewrk/zig