The new behavior is even more bizarre than I had first thought.

---------------------------------------------------------------------------
% cat foo.mli
type ('a, 'b) t;;
val iter: ('a -> 'b -> 'unit) -> ('a, 'b) t -> unit

% ocamlc -v -i -c foo.mli
The Objective Caml compiler, version 1.06
Standard library directory: /home/stodghil/usr/sparc-solaris/lib/ocaml
type ('a, 'b) t
val iter : ('a -> 'b -> 'c) -> ('a, 'b) t -> unit
% 
---------------------------------------------------------------------------

Why is the generated type different than the declared type?

-- 
Paul Stodghill <stodghil@cs.cornell.edu>
http://www.cs.cornell.edu/home/stodghil/home.html