Do some work on this. It still doesn't compile, let

followvars.nl:
	Do some work on this.  It still doesn't compile, let
	alone work.

mode_info.nl:
	Fix bug in last change.

hlds_out.nl:
	A couple of very minor fixes.

switch_detection.nl:
	Fix a bug so that 2nd-argument indexing works.

compiler/hlds_out.m

@@ -230,7 +230,8 @@ hlds_out__write_pred(Indent, PredId, PredInfo) -->
 	{ ClausesInfo = clauses_info(VarSet, VarTypes, HeadVars, Clauses) },
 	hlds_out__write_var_types(Indent, VarSet, VarTypes, TVarSet),
 	hlds_out__write_clauses(Indent, PredId, VarSet, HeadVars, Clauses),
-	hlds_out__write_procs(Indent, PredId, Imported, ProcTable).
+	hlds_out__write_procs(Indent, PredId, Imported, ProcTable),
+	io__write_string("\n").
 
 :- pred hlds_out__write_clauses(int, pred_id, varset, list(var), list(clause),
 				io__state, io__state).
@@ -571,24 +572,21 @@ hlds_out__write_var_types_2([Var | Vars], Indent, VarSet, VarTypes, TypeVarSet)
 
 hlds_out__write_types(Indent, _X) -->
 	hlds_out__write_indent(Indent),
-	% XXX
-	io__write_string("\n").
+	io__write_string("% types (sorry, output of types not implemented)\n").
 
 :- pred hlds_out__write_insts(int, inst_table, io__state, io__state).
 :- mode hlds_out__write_insts(in, in, in, out).
 
 hlds_out__write_insts(Indent, _X) -->
 	hlds_out__write_indent(Indent),
-	% XXX
-	io__write_string("\n").
+	io__write_string("% insts (sorry, output of insts not implemented)\n").
 
 :- pred hlds_out__write_modes(int, mode_table, io__state, io__state).
 :- mode hlds_out__write_modes(in, in, in, out).
 
 hlds_out__write_modes(Indent, _X) -->
 	hlds_out__write_indent(Indent),
-	% XXX
-	io__write_string("\n").
+	io__write_string("% modes (sorry, output of modes not implemented)\n").
 
 :- pred hlds_out__write_mode_list(int, list(mode), io__state, io__state).
 :- mode hlds_out__write_mode_list(in, in, in, out).

compiler/mode_info.m

@@ -163,6 +163,35 @@
 :- pred mode_info_set_delay_info(delay_info, mode_info, mode_info).
 :- mode mode_info_set_delay_info(in, mode_info_di, mode_info_uo) is det.
 
+:- inst uniq_mode_info	=	bound_unique(
+					mode_info(
+						ground_unique, ground,
+						ground, ground, ground, ground,
+						ground, ground, ground, ground,
+						ground
+					)
+				).
+
+:- mode mode_info_uo :: free -> uniq_mode_info.
+:- mode mode_info_ui :: uniq_mode_info -> uniq_mode_info.
+:- mode mode_info_di :: uniq_mode_info -> dead.
+
+	% Some fiddly modes used when we want to extract
+	% the io_state from a mode_info struct and then put it back again.
+
+:- inst mode_info_no_io	=	bound_unique(
+					mode_info(
+						dead, ground,
+						ground, ground, ground, ground,
+						ground, ground, ground, ground,
+						ground
+					)
+				).
+
+:- mode mode_info_get_io_state	:: uniq_mode_info -> mode_info_no_io.
+:- mode mode_info_no_io		:: mode_info_no_io -> mode_info_no_io.
+:- mode mode_info_set_io_state	:: mode_info_no_io -> dead.
+
 %-----------------------------------------------------------------------------%
 %-----------------------------------------------------------------------------%
 
@@ -195,35 +224,6 @@
 	% the io_state and the struct itself unique, but with
 	% multiple references allowed for the other parts.
 
-:- inst uniq_mode_info	=	bound_unique(
-					mode_info(
-						ground_unique, ground,
-						ground, ground, ground, ground,
-						ground, ground, ground, ground,
-						ground
-					)
-				).
-
-:- mode mode_info_uo :: free -> uniq_mode_info.
-:- mode mode_info_ui :: uniq_mode_info -> uniq_mode_info.
-:- mode mode_info_di :: uniq_mode_info -> dead.
-
-	% Some fiddly modes used when we want to extract
-	% the io_state from a mode_info struct and then put it back again.
-
-:- inst mode_info_no_io	=	bound_unique(
-					mode_info(
-						dead, ground,
-						ground, ground, ground, ground,
-						ground, ground, ground, ground,
-						ground
-					)
-				).
-
-:- mode mode_info_get_io_state	:: uniq_mode_info -> mode_info_no_io.
-:- mode mode_info_no_io		:: mode_info_no_io -> mode_info_no_io.
-:- mode mode_info_set_io_state	:: mode_info_no_io -> dead.
-
 %-----------------------------------------------------------------------------%
 
 	% Initialize the mode_info

compiler/switch_detection.m

@@ -219,14 +219,12 @@ partition_disj_2([Goal | Goals], Var, Cases0, Cases) :-
 :- mode find_unify_var_functor(in, in, out) is semidet.
 
 find_unify_var_functor([Goal - _GoalInfo | Goals], Var, Functor) :-
-	( Goal = unify(term__variable(Var0), term__functor(Name, Args, _),
+	( Goal = unify(term__variable(Var), term__functor(Name, Args, _),
 			_, _, _) ->
-		Var = Var0,
 		list__length(Args, Arity),
 		make_functor_cons_id(Name, Arity, Functor)
-	; Goal = unify(term__functor(Name, Args, _), term__variable(Var0),
+	; Goal = unify(term__functor(Name, Args, _), term__variable(Var),
 			_, _, _) ->
-		Var = Var0,
 		list__length(Args, Arity),
 		make_functor_cons_id(Name, Arity, Functor)
 	; Goal = unify(_, _, _, _, _) ->