Quotes of the week

You don't need more than two for STRINGIFY to work reliably, but the # and ## operators only work in macro replacement lists. In this case, I guess IS_DEFINED provides that extra level of indirection to do the CONFIG_##x pasting.

<sys/param.h> on Linux and BSD provide PASTE and XPASTE (the latter being more commonly used to ensure parameters are evaluated properly) to do this pasting in an ad hoc manner.