[perl-Glib-Object-Introspection] Return undef for argumens with no type information

[Torsten Schönfeld <tsch src gnome org>]

commit 73e925863c92a2d0c7bbe86c5be0aceeaa5ab7a0
Author: Torsten Schönfeld <kaffeetisch gmx de>
Date:   Mon Apr 26 00:29:46 2010 +0200

    Return undef for argumens with no type information

 GObjectIntrospection.xs |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/GObjectIntrospection.xs b/GObjectIntrospection.xs
index 549db1a..a1ee744 100644
--- a/GObjectIntrospection.xs
+++ b/GObjectIntrospection.xs
@@ -859,7 +859,8 @@ arg_to_sv (const GArgument * arg,
 
 	switch (tag) {
 	    case GI_TYPE_TAG_VOID:
-		return NULL;
+		dwarn ("    argument with no type information -> undef\n");
+		return &PL_sv_undef;
 
 	    case GI_TYPE_TAG_BOOLEAN:
 		return boolSV (arg->v_boolean);