Example: there's no point in compiling both -desc and -norm if there are no +Err/* tags in the fst. This can be checked for during configure time, and thus easily be made to skip.

In the case of -desc vs -norm, there are four options at least:

- build only -desc
- build only -norm
- build one, and symlink the other to the first
- build a new one, e.g. analyser-gt-all.?fst

The symlink alternative is probably the best one, as all other operations can assume fixed filenames.

Other candidates:
- disamb (if no semantic tags)
- oahpa (if no dialects?)

There might be more, but most other fst's are built conditionally in any case, requiring explicit enabling at configure time.

Another thing is to look at the defaults: e.g. do we always need the area variants (when those are declared), or should the default be to not build them, requiring enabling at config time instead? The same goes for orthographical and writing system variants.