OCaml glitch breaks compilation of CIRCE2 parts with 3.12.X

[Juergen Reuter]

The compilation of the CIRCE2 OCaml code does not work with OCaml version 3.12.X:

/usr/local/bin/ocamlopt  -inline 64  -o commands.cmx -c ../../../circe2/src/commands.ml
File "../../../circe2/src/commands.ml", line 44, characters 14-23:
Error: Unbound record field label scale1 

It seems that inheritance is not understood (correctly) until OCaml 4. The proposed solution from JRR is to change:

    44    begin match ch.scale1, ch.scale2 with 

into

    44    begin match ch.Syntax.scale1, ch.Syntax.scale2 with 

Then the code compiles, and all tests work fine.

[Juergen Reuter]

After approval by TO resolved in r5977.