RFC: "Crochet" build tool

[Tim Kientzle]

On Mar 27, 2013, at 9:39 AM, Adrian Chadd wrote:
> 
> One of the big changes I made for my build scripts is to separate out
> toolchain/userland building (which is done once for a given
> architecture) from kernel building (once per target) from image
> building (again, once per target.)

The tricky part for this is making sure that things do get
rebuilt if you change the options.

Crochet handles this pretty cleanly now though I'm
still fussing with some of the details.

Tim