bug fix for name mangling

[Fergus Henderson]

Tyson has already reviewed this one.

Estimated hours taken: 2

Fix a bug which caused link errors for tests/hard_coded/name_mangling.m 
in grades `jump' and `fast'.

compiler/llds_out.m:
	When mangling and qualifying the symbol names for special predicates
	(unification, compare, index), make sure that we do the mangling
	first and the qualification afterwards rather than vice versa.

Index: llds_out.m
===================================================================
RCS file: /home/staff/zs/imp/mercury/compiler/llds_out.m,v
retrieving revision 1.43
diff -u -r1.43 llds_out.m
--- llds_out.m	1997/04/17 07:47:25	1.43
+++ llds_out.m	1997/04/18 05:42:56
@@ -2160,24 +2160,35 @@
 
 	% For a special proc, output a label of the form:
 	% mercury____<PredName>___<TypeModule>__<TypeName>_<TypeArity>_<Mode>
-get_proc_label(special_proc(Module, PredName, TypeModule, TypeName0, TypeArity,
+get_proc_label(special_proc(Module, PredName, TypeModule, TypeName, TypeArity,
 				ModeNum0), ProcLabelString) :-
+	% figure out the LabelName
 	DummyArity = -1,	% not used by get_label_name.
 	get_label_name("", predicate, "", PredName, DummyArity, LabelName),
+
+	% figure out the ModeNumString
 	string__int_to_string(TypeArity, TypeArityString),
 	proc_id_to_int(ModeNum0, ModeInt),
 	ModeNum is ModeInt mod 10000,		% strip off the priority
 	string__int_to_string(ModeNum, ModeNumString),
-	% Handle locally produced unification preds for imported types.
-	( Module \= TypeModule ->
-		string__append(Module, "__", ExtraModule)
-	;
-		ExtraModule = ""
-	),
-	llds_out__maybe_qualify_name(TypeModule, TypeName0, TypeName1),
-	string__append(ExtraModule, TypeName1, TypeName2),
-	llds_out__name_mangle(TypeName2, TypeName),
-	string__append_list( [LabelName, "_", TypeName, 
+
+	% mangle all the relevent names
+	llds_out__name_mangle(Module, MangledModule),
+	llds_out__name_mangle(TypeModule, MangledTypeModule),
+	llds_out__name_mangle(TypeName, MangledTypeName),
+
+	% Module-qualify the type name.
+	% To handle locally produced unification preds for imported types,
+	% we need to qualify it with both the module name of the
+	% type, and also (if it is different) the module name of the
+	% current module.
+	llds_out__maybe_qualify_name(MangledTypeModule, MangledTypeName,
+		QualifiedMangledTypeName),
+	llds_out__maybe_qualify_name(MangledModule, QualifiedMangledTypeName,
+		FullyQualifiedMangledTypeName),
+
+	% join it all together
+	string__append_list( [LabelName, "_", FullyQualifiedMangledTypeName, 
 		"_", TypeArityString, "_", ModeNumString], 
 		ProcLabelString).
 

-- 
Fergus Henderson <fjh at cs.mu.oz.au>   |  "I have always known that the pursuit
WWW: <http://www.cs.mu.oz.au/~fjh>   |  of excellence is a lethal habit"
PGP: finger fjh at 128.250.37.3         |     -- the last words of T. S. Garp.