civicrm/civicrm-core — pull request #2342 by totten (2014-01-15 04:26:22+00:00)
Title: GenCode - Add an optional caching mode.

If CIVICRM_GENCODE_DIGEST is set, then GenCode will write out a digest of all
its inputs & templates. If someone tries to rerun with the same inputs, then
GenCode will do nothing.