I'm trying to use dune's include_subdirs qualified and the select target to define alternative dependencies/optional modules.

I have tried creating lib/foo/file.enabled.ml, lib/foo/file.disabled.ml, and using a dune file like

(library
 (public_name dune_qualified_select)
 (name main)
 (libraries
   (select foo.file.ml from
    (utop -> foo.file.enabled.ml)
    ( -> foo.file.disabled.ml )
   )
 )
)

(include_subdirs qualified)
(dirs :standard)

I keep hitting errors like Error: No rule found for bin/foo.file.enabled.ml. I also tried creating lib/foo/file/disabled.ml for example, but the issue is the same. How are those two options supposed to work together?

Wondering if this is somehow related to #11119? I know there are reported issue for the unqualified mode too (#4383).