inducer/compyte — pull request #20 by yuyichao (2014-05-10 14:35:32+00:00)
Title: Use the documented struct.calcsize to determine machine word size for better pypy support.

See https://github.com/pyopencl/pyopencl/issues/36
`__itemsize__` is an undocumented cpython specific api that is not possible to support in pypy.
This patch fix the problem by using the documented `struct.calcsize` function to achieve the same purpose.