sem_ch12.adb (Save_Entity_Descendant): Use syntactic field names on known node types, rather than untyped fields.
* sem_ch12.adb (Save_Entity_Descendant): Use syntactic field names
on known node types, rather than untyped fields. Further cleanups.
* sem_ch12.adb:
(Save_Entity_Descendant): Minor comment update.
(Copy_Generic_Node): Deal with incorrect reference to Associated_Node
of an N_Attribute_Reference node. As per note below, this does not
eliminate need for Associated_Node in attribute ref nodes.
(Associated_Node): Documentation explicitly mentions attribute
reference nodes, since this field is used in such nodes.
* sem_ch12.adb (Associated_Node): Minor documentation cleanup.
From-SVN: r47954
