URL: http://bytes.com/topic/c/answers/216333-binary-constant-macros

Neat hack to get compile-time binary constants in C using the preprocessor.

B8(10101010). Works by stringifying to hex, then masking & adding. B32, etc work by using B8 and shifting.

"I've been missing the lack of support for binary numeric literals in
C. To get around it I wrote the following handy macros, which allows
you to simply write something like:

whatever = B8(10101010);

and will translate as:

whatever = 85;

(compile-time constant)"