Comment author: @lpw25

For completeness, the following example is the one that I actually started looking at -- partly due to its dubious error message -- but the problem is the same as that of the more minimal example above:

module rec M : sig
  type a
  module type B = sig val x : M.a end
end = struct
  type a
  module type B = M.B
end;;

Characters 78-125:
  ........struct
    type a
    module type B = M.B
  end..
Error: Signature mismatch:
       Modules do not match:
         sig type a = M.a module type B = M.B end
       is not included in
         sig type a module type B = sig val x : M.a end end
       Module type declarations do not match:
         module type B = M.B
       does not match
         module type B = sig val x : M.a end
       At position module type B = <here>
       Modules do not match: M.B is not included in sig val x : M.a end
       At position module type B = <here>
       Values do not match: val x : M.a is not included in val x : M.a

This issue has been open one year with no activity. Consequently, it is being marked with the "stale" label. What this means is that the issue will be automatically closed in 30 days unless more comments are added or the "stale" label is removed. Comments that provide new information on the issue are especially welcome: is it still reproducible? did it appear in other contexts? how critical is it? etc.

This issue has been open one year with no activity. Consequently, it is being marked with the "stale" label. What this means is that the issue will be automatically closed in 30 days unless more comments are added or the "stale" label is removed. Comments that provide new information on the issue are especially welcome: is it still reproducible? did it appear in other contexts? how critical is it? etc.

This issue has been open one year with no activity. Consequently, it is being marked with the "stale" label. What this means is that the issue will be automatically closed in 30 days unless more comments are added or the "stale" label is removed. Comments that provide new information on the issue are especially welcome: is it still reproducible? did it appear in other contexts? how critical is it? etc.

This issue has been open one year with no activity. Consequently, it is being marked with the "stale" label. What this means is that the issue will be automatically closed in 30 days unless more comments are added or the "stale" label is removed. Comments that provide new information on the issue are especially welcome: is it still reproducible? did it appear in other contexts? how critical is it? etc.