- ./install tries to build extra stuff, and is rigged to ignore any
  errors and keep going, as those components are considered optional.

  We might want to consider patching that out and cause a hard-failure
  if errors are detected, and/or move building them into ./install, as things
  randomly not getting built/installed might not play nice with PLIST.

- Something built by ./install wants libSDL, so we'll want to use the Options
  framework to selectively-enable using it (which'll probably require patching
  the ./install script).

- Verify if we should use ``BUILDLINK_DEPMETHOD.obnc?= build`` and/or
  ``.include "../../devel/boehm-gc/buildlink3.mk"`` in buildlink3.mk.

- Update DESCR so it's not just a copy of COMMENT.
