diff -urN mercury-tests-0.13.1.orig/hard_coded/dir_test.exp mercury-tests-0.13.1/hard_coded/dir_test.exp
--- mercury-tests-0.13.1.orig/hard_coded/dir_test.exp	2003-07-29 03:50:45.000000000 +1200
+++ mercury-tests-0.13.1/hard_coded/dir_test.exp	2006-12-04 21:44:54.000000000 +1300
@@ -130,7 +130,6 @@
 "foo"/"bar/baz" = "foo\bar\baz".
 "foo/"/"bar/baz" = "foo\bar\baz".
 checking whether `unwritable' is readable...ok
-unwritable file found to be unwritable
 make_directory succeeded
 make_directory succeeded
 dir.make_single_directory with non-existent parent failed as expected.
diff -urN mercury-tests-0.13.1.orig/hard_coded/dir_test.exp2 mercury-tests-0.13.1/hard_coded/dir_test.exp2
--- mercury-tests-0.13.1.orig/hard_coded/dir_test.exp2	2003-07-29 03:50:45.000000000 +1200
+++ mercury-tests-0.13.1/hard_coded/dir_test.exp2	2006-12-04 21:44:54.000000000 +1300
@@ -127,7 +127,6 @@
 "foo"/"bar/baz" = "foo/bar/baz".
 "foo/"/"bar/baz" = "foo/bar/baz".
 checking whether `unwritable' is readable...ok
-unwritable file found to be unwritable
 make_directory succeeded
 make_directory succeeded
 dir.make_single_directory with non-existent parent failed as expected.
diff -urN mercury-tests-0.13.1.orig/hard_coded/dir_test.exp3 mercury-tests-0.13.1/hard_coded/dir_test.exp3
--- mercury-tests-0.13.1.orig/hard_coded/dir_test.exp3	2003-07-29 03:50:45.000000000 +1200
+++ mercury-tests-0.13.1/hard_coded/dir_test.exp3	2006-12-04 21:44:54.000000000 +1300
@@ -130,7 +130,6 @@
 "foo"/"bar/baz" = "foo/bar/baz".
 "foo/"/"bar/baz" = "foo/bar/baz".
 checking whether `unwritable' is readable...ok
-unwritable file found to be unwritable
 make_directory succeeded
 make_directory succeeded
 dir.make_single_directory with non-existent parent failed as expected.
diff -urN mercury-tests-0.13.1.orig/hard_coded/dir_test.m mercury-tests-0.13.1/hard_coded/dir_test.m
--- mercury-tests-0.13.1.orig/hard_coded/dir_test.m	2006-03-29 20:08:00.000000000 +1200
+++ mercury-tests-0.13.1/hard_coded/dir_test.m	2006-12-04 21:44:54.000000000 +1300
@@ -50,16 +50,6 @@
 	io__write(ReadResult),
 	io__nl,
 
-	io__check_file_accessibility("unwritable",
-		[read, write], WriteResult),
-	( { WriteResult = ok } ->
-		io__write_string(
-		"Error: unwritable file found to be writable\n")
-	;
-		io__write_string(
-		"unwritable file found to be unwritable\n")
-	),
-
 	{ Dir1 = "test_dir"/"d1" },
 	test0("make_directory", dir__make_directory(Dir1)),
 	% Test making a directory that already exists.
diff -urN mercury-tests-0.13.1.orig/mdbrc mercury-tests-0.13.1/mdbrc
--- mercury-tests-0.13.1.orig/mdbrc	1970-01-01 12:00:00.000000000 +1200
+++ mercury-tests-0.13.1/mdbrc	2006-12-04 21:44:54.000000000 +1300
@@ -0,0 +1,19 @@
+source MDB_DOC
+alias	s	step
+alias	g	goto
+alias	f	finish
+alias	r	retry
+alias	v	vars
+alias	p	print
+alias	P	print *
+alias	d	stack
+alias	c	continue
+alias	b	break
+alias	h	help
+alias	?	help
+alias	excp	exception
+alias	e	exception
+alias	EMPTY	step
+alias	NUMBER	step
+xml_browser_cmd ''
+xml_tmp_filename ''
diff -urN mercury-tests-0.13.1.orig/tabling/loopcheck.exp5 mercury-tests-0.13.1/tabling/loopcheck.exp5
--- mercury-tests-0.13.1.orig/tabling/loopcheck.exp5	1970-01-01 12:00:00.000000000 +1200
+++ mercury-tests-0.13.1/tabling/loopcheck.exp5	2006-12-04 21:44:54.000000000 +1300
@@ -0,0 +1,3 @@
+Uncaught Mercury exception:
+Software Error: detected infinite recursion in pred loopcheck.loop/1
+Stack dump not available in this grade.
diff -urN mercury-tests-0.13.1.orig/tabling/loopcheck_nondet.exp2 mercury-tests-0.13.1/tabling/loopcheck_nondet.exp2
--- mercury-tests-0.13.1.orig/tabling/loopcheck_nondet.exp2	1970-01-01 12:00:00.000000000 +1200
+++ mercury-tests-0.13.1/tabling/loopcheck_nondet.exp2	2006-12-04 21:44:54.000000000 +1300
@@ -0,0 +1,3 @@
+Uncaught Mercury exception:
+Software Error: detected infinite recursion in pred loopcheck_nondet.loop/2
+Stack dump not available in this grade.
diff -urN mercury-tests-0.13.1.orig/tabling/tc_loop.exp3 mercury-tests-0.13.1/tabling/tc_loop.exp3
--- mercury-tests-0.13.1.orig/tabling/tc_loop.exp3	1970-01-01 12:00:00.000000000 +1200
+++ mercury-tests-0.13.1/tabling/tc_loop.exp3	2006-12-04 21:44:54.000000000 +1300
@@ -0,0 +1,3 @@
+Uncaught Mercury exception:
+Software Error: detected infinite recursion in pred tc_loop.tc/2
+Stack dump not available in this grade.
diff -urN mercury-tests-0.13.1.orig/tabling/tc_memo.exp2 mercury-tests-0.13.1/tabling/tc_memo.exp2
--- mercury-tests-0.13.1.orig/tabling/tc_memo.exp2	1970-01-01 12:00:00.000000000 +1200
+++ mercury-tests-0.13.1/tabling/tc_memo.exp2	2006-12-04 21:44:54.000000000 +1300
@@ -0,0 +1,3 @@
+Uncaught Mercury exception:
+Software Error: detected infinite recursion in pred tc_memo.tc/2
+Stack dump not available in this grade.
diff -urN mercury-tests-0.13.1.orig/tabling/tc_memo2.exp2 mercury-tests-0.13.1/tabling/tc_memo2.exp2
--- mercury-tests-0.13.1.orig/tabling/tc_memo2.exp2	1970-01-01 12:00:00.000000000 +1200
+++ mercury-tests-0.13.1/tabling/tc_memo2.exp2	2006-12-04 21:44:54.000000000 +1300
@@ -0,0 +1,3 @@
+Uncaught Mercury exception:
+Software Error: detected need for minimal model in pred tc_memo2.tc/2
+Stack dump not available in this grade.
diff -urN mercury-tests-0.13.1.orig/valid/Mmakefile mercury-tests-0.13.1/valid/Mmakefile
--- mercury-tests-0.13.1.orig/valid/Mmakefile	2006-11-08 14:36:30.000000000 +1300
+++ mercury-tests-0.13.1/valid/Mmakefile	2006-12-04 21:44:54.000000000 +1300
@@ -400,3 +400,5 @@
 	rm -f *.err *.h
 
 #-----------------------------------------------------------------------------#
+
+MCFLAGS-ho_and_type_spec_bug+=--no-optimize-higher-order
diff -urN mercury-tests-0.13.1.orig/valid/Mmakefile.orig mercury-tests-0.13.1/valid/Mmakefile.orig
--- mercury-tests-0.13.1.orig/valid/Mmakefile.orig	1970-01-01 12:00:00.000000000 +1200
+++ mercury-tests-0.13.1/valid/Mmakefile.orig	2006-11-08 14:36:30.000000000 +1300
@@ -0,0 +1,402 @@
+#-----------------------------------------------------------------------------#
+
+THIS_DIR = valid
+
+#-----------------------------------------------------------------------------#
+
+# please keep these lists sorted
+AGC_PROGS= \
+	agc_graph \
+	agc_ho_pred \
+	agc_ite \
+	agc_unbound_typevars \
+	agc_unbound_typevars2 \
+	agc_unused_in
+
+TRAIL_PROGS= \
+	complex_failure \
+	semi_fail_in_non_ite
+
+TYPECLASS_PROGS= \
+	abstract_typeclass \
+	complex_constraint \
+	constraint_proof_bug \
+	exists_bug \
+	exists_fundeps \
+	exists_fundeps_2 \
+	exists_fundeps_3 \
+	flatten_conj_bug \
+	func_class \
+	func_method \
+	fundeps \
+	instance_superclass \
+	instance_unconstrained_tvar \
+	mpj2 \
+	mpj5 \
+	mpj6 \
+	mpj7 \
+	repeated_class_constraint \
+	superclass_bug \
+	superclass_improvement \
+	tc_map_lookup \
+	typeclass_constraint_no_var \
+	typeclass_constraint_nonvar_bug \
+	typeclass_det_warning
+
+	# This test is compiled with --no-special-preds,
+	# which doesn't work in jump.* and fast.* grades.
+NO_SPECIAL_PREDS_PROGS= \
+	unify_typeinfo_bug
+
+	# Tests for which we should only produce a `.il' file.
+IL_PROGS = \
+	csharp_hello \
+	foreign_type_spec
+
+OTHER_PROGS= \
+	any_inst_merge \
+	any_matches_bound \
+	big_foreign_type \
+	builtin_false \
+	common_struct_bug \
+	complicated_unify \
+	compl_unify_bug \
+	constrained_poly_bound_arg \
+	constrained_poly_insts \
+	constraint_prop_bug \
+	constructor_arg_names \
+	dcg_test \
+	deforest_bug \
+	deforest_loop \
+	deforest_rerun_det \
+	det_condition \
+	det_inference \
+	det_switch \
+	double_vn \
+	easy_nondet_test \
+	easy_nondet_test_2 \
+	empty_bound_inst_list \
+	empty_switch \
+	error \
+	eval \
+	existential_cons \
+	explicit_quant \
+	export_before_func \
+	exported_foreign_type \
+	fail_ite \
+	followcode_det_problem \
+	foreign_underscore_var \
+	func_default_modes \
+	func_in_head \
+	func_int_bug_main \
+	hawkins_switch_bug \
+	headvar_not_found \
+	higher_order \
+	higher_order2 \
+	higher_order3 \
+	higher_order4 \
+	higher_order5 \
+	higher_order_implied_mode \
+	ho_and_type_spec_bug \
+	ho_func_call \
+	ho_inst \
+	ho_unify \
+	id_type_bug \
+	implied_mode \
+	impure_lambda_bug \
+	indexing \
+	inhibit_warn_test \
+	inlining_bug \
+	inst_perf_bug_1 \
+	int64 \
+	intermod_bug_nested \
+	intermod_dcg_bug \
+	intermod_impure \
+	intermod_lambda \
+	intermod_nested \
+	intermod_nested_module \
+	intermod_nested_module_bug \
+	intermod_nested_uniq \
+	intermod_pragma_import \
+	intermod_quote \
+	intermod_record \
+	intermod_test \
+	intermod_typeclass \
+	intermod_type_spec \
+	intermod_user_equality \
+	intermod_user_equality_nested \
+	lambda_inference\
+	lambda_instmap_bug \
+	lambda_output \
+	lambda_quant \
+	lambda_quant_bug \
+	lambda_recompute \
+	lambda_struct_bug \
+	lambda_switch \
+	lambda_type \
+	lazy_list \
+	liveness_nonlocals \
+	livevals_seq \
+	loop \
+	loop_in_disj \
+	loop_inv_bug \
+	mc_bag \
+	mc_extra_nonlocals \
+	mc_graph \
+	mc_hhf_nonlocals_bug \
+	mc_implied_modes \
+	merge_ground_any \
+	middle_rec_labels \
+	modes_bug \
+	mode_syntax \
+	module_a \
+	module_b \
+	module_c \
+	module_d \
+	module_e \
+	mostly_uniq_bug \
+	mostly_uniq_mode_inf \
+	mostly_uniq_neg \
+	multidet_prune1 \
+	multidet_test \
+	nasty_func_test \
+	nested_mod_type_bug \
+	nested_module_bug \
+	no_warn_obsolete \
+	nondet_live \
+	overloading \
+	param_mode_bug \
+	parsing_bug_main \
+	pred_with_no_modes \
+	qualified_cons_id \
+	quantifier_warning \
+	record_syntax_bug \
+	record_syntax_bug_2 \
+	record_syntax_bug_3 \
+	record_syntax_bug_4 \
+	record_syntax_bug_5 \
+	recursive_no_tag_type \
+	reg_bug \
+	same_length_2 \
+	semidet_disj \
+	shape_type \
+	simplify_bug \
+	simplify_bug2 \
+	size_prof_ho_bug \
+	soln_context \
+	solv \
+	solver_type_bug \
+	solver_type_bug_2 \
+	solver_type_mutable_bug \
+	some_switch \
+	spurious_purity_warning \
+	stack_alloc \
+	stack_opt_simplify \
+	state_var_bug \
+	state_var_mode_bug \
+	state_var_mode_bug2 \
+	static \
+	subtype_switch \
+	switch_detection_bug \
+	switch_detection_bug2 \
+	switches \
+	tabled_for_io \
+	tabled_io \
+	transitive_instance \
+	tricky_assert2 \
+	tricky_ite \
+	tuple_eqv \
+	two_pragma_c_codes \
+	two_way_unif \
+	typeclass_inlining_bug \
+	type_inf_ambig_test \
+	unbound_inst_var \
+	unbound_tvar_in_lambda \
+	undead_proc \
+	uniq_mode_inf_bug \
+	uniq_unify \
+	unreachable_code \
+	unused_args_test2 \
+	vn_float \
+	zero_arity
+
+DEEP_PROF_CAPABLE_PROGS = \
+	impure_detism
+
+# These tests require debugging, which hasn't been implemented for
+# the MLDS backend.
+#
+LLDS_PROGS= \
+	exists_cast_bug \
+	untuple_bug
+
+# These tests only work in grades that support parallel conjunction.
+#
+PAR_CONJ_PROGS = \
+	par_dummy \
+	par_dupelim \
+	par_saved_const
+
+# The following programs require that num_tag_bits >= 1
+RESERVE_TAG_PROGS = \
+	reserve_tag
+
+# XXX The mode system can't handle the following test cases yet:
+#	assoc_list_bug
+#	determinism
+#	inst_perf_bug_2
+#	mode_merge_insts
+#	unify_inst_bug
+#
+# XXX We also don't pass this one (see the comments in it for details):
+#	mode_selection
+#
+# XXX The following test is not valid under the current Mercury
+# language rules:
+#	field_detism
+
+# The agc.* tests don't work in --high-level-code grades,
+# except hl*.agc*, because they require grade-specific header
+# files to be installed.
+ifeq "$(findstring hl,$(GRADE))$(findstring .agc,$(GRADE))" "hl"
+	PROGS0 = $(TYPECLASS_PROGS) $(OTHER_PROGS)
+else
+	# The agc.* tests don't work in the il grades, as the CLR has
+	# its own builtin GC.
+	# The agc.* tests also don't work in minimal model grades,
+	# because the collector doesn't scan the copied areas of the stacks.
+	ifneq "$(findstring il,$(GRADE))$(findstring mm,$(GRADE))" ""
+		PROGS0 = $(TYPECLASS_PROGS) $(OTHER_PROGS)
+	else
+		PROGS0 = $(AGC_PROGS) $(TYPECLASS_PROGS) $(OTHER_PROGS)
+	endif
+endif
+
+# Base grades `jump' and `fast'
+# cannot be used with `--no-special-preds'
+
+ifneq "$(findstring asm_,$(GRADE))" ""
+	PROGS1=$(NO_SPECIAL_PREDS_PROGS) $(PROGS0)
+else
+	ifneq "$(findstring jump,$(GRADE))" ""
+		PROGS1=$(PROGS0)
+	else
+		ifneq "$(findstring fast,$(GRADE))" ""
+			PROGS1=$(PROGS0)
+		else
+			PROGS1=$(NO_SPECIAL_PREDS_PROGS) $(PROGS0)
+		endif
+	endif
+endif
+
+ifneq "$(findstring mm,$(GRADE))" ""
+	PROGS2=$(PROGS1)
+else
+	PROGS2=$(PROGS1) $(TRAIL_PROGS)
+endif
+
+ifneq "$(filter java% il%,$(GRADE))$(findstring profdeep,$(GRADE))" ""
+	# We currently don't do any testing in grade java on this directory.
+	ifneq "$(findstring java,$(GRADE))$" ""
+		PROGS3 =
+	else
+		PROGS3 = $(PROGS2)
+	endif
+else
+	PROGS3 = $(PROGS2)
+endif
+
+ifeq "$(filter hl% java% il%,$(GRADE))" ""
+	PROGS4 = $(PROGS3) $(DEEP_PROF_CAPABLE_PROGS) $(LLDS_PROGS)
+else
+	PROGS4 = $(PROGS3)
+endif
+
+ifneq "$(findstring decldebug,$(GRADE))" ""
+	PROGS5 = $(PROGS4)
+else
+	PROGS5 = $(PROGS4) $(PAR_CONJ_PROGS)
+endif
+
+ifeq "$(filter java% il%,$(GRADE))" ""
+	OBJ_PROGS = $(PROGS5) $(RESERVE_TAG_PROGS)
+else
+	OBJ_PROGS = $(PROGS5)
+endif
+
+ifneq "$(findstring tsw,$(GRADE))$(findstring tsc,$(GRADE))" ""
+	PROGS = $(OBJ_PROGS)
+else
+	PROGS = $(OBJ_PROGS) $(IL_PROGS)
+endif
+
+# `mmc --make' doesn't expect subdirectories to appear in targets.
+ifeq ($(MMAKE_USE_MMC_MAKE),yes)
+OS_SUBDIR=
+ILS_SUBDIR=
+DLLS_SUBDIR=
+else
+OS_SUBDIR=$(os_subdir)
+ILS_SUBDIR=$(ils_subdir)
+DLLS_SUBDIR=$(dlls_subdir)
+endif
+
+
+ifeq ($(findstring il,$(GRADE)),il)
+	TARGET_OBJ_EXT=dll
+	TARGET_OBJ_SUBDIR=$(DLLS_SUBDIR)
+else
+	TARGET_OBJ_EXT=$(O)
+	TARGET_OBJ_SUBDIR=$(OS_SUBDIR)
+endif
+OBJS =	$(OBJ_PROGS:%=$(TARGET_OBJ_SUBDIR)%.$(TARGET_OBJ_EXT)) \
+		$(IL_PROGS:%=$(ILS_SUBDIR)%.il)
+
+#-----------------------------------------------------------------------------#
+
+TESTS = $(PROGS)
+SUBDIRS=
+TESTS_DIR=..
+include $(TESTS_DIR)/Mmake.common
+
+# When compiling using the installed libraries, setting GRADEFLAGS may
+# may cause mgnuc to look for the `.mih' files for a non-installed grade.
+# test_mercury runs the tests using the installed libraries, so GRADEFLAGS
+# won't be set, but test_mercury runs the tests in at least one `.tr' grade
+# on all machines, so it isn't a problem.
+ifneq ($(origin WORKSPACE),undefined)
+GRADEFLAGS_TRAIL = --use-trail
+else
+GRADEFLAGS_TRAIL =
+endif
+# Make sure GRADEFLAGS_TRAIL is passed to `mmc --make'.
+export GRADEFLAGS_TRAIL
+
+# Module-specific options should go in Mercury.options so they
+# can be found by `mmc --make'.
+include Mercury.options
+
+$(OBJ_PROGS:%=%.runtest): %.runtest: %.$(TARGET_OBJ_EXT) ;
+
+$(IL_PROGS:%=%.runtest): %.runtest: %.il ;
+
+#-----------------------------------------------------------------------------#
+
+# XXX mmake should automatically handle these two dependencies.
+$(dates_subdir)intermod_nested_module2.date: \
+	$(date0s_subdir)intermod_nested_module2.date0
+$(dates_subdir)intermod_user_equality_nested2.date: \
+	$(date0s_subdir)intermod_user_equality_nested2.date0
+
+objs:	$(OBJS)
+
+printtests:
+	@echo $(PROGS)
+
+printobjs:
+	@echo $(OBJS)
+
+clean_local:
+	rm -f *.err *.h
+
+#-----------------------------------------------------------------------------#