Poudriere - caching amonst port trees?

[Francisco Reyes]

Have a working Poudriere setup with two port trees. Vast majority of the ports are the same with the same options. Only a handful of ports have different options.

is there any way to take advantage of one build as cache for the second for common ports? This would also help for larger common ports like llvm. Could build llvm on it's own port tree then run the other two ideally using the results from the llvm run.