void sgen_card_table_reset_region (mword start, mword end);
void* sgen_card_table_align_pointer (void *ptr);
void sgen_card_table_mark_range (mword address, mword size);
-void sgen_cardtable_scan_object (char *obj, mword obj_size, guint8 *cards,
+void sgen_cardtable_scan_object (GCObject *obj, mword obj_size, guint8 *cards,
gboolean mod_union, ScanCopyContext ctx);
gboolean sgen_card_table_get_card_data (guint8 *dest, mword address, mword cards);