[Ada] Remove support for obsolete switch

Index: gcc-interface/utils.c
===================================================================
--- gcc-interface/utils.c	(revision 165250)
+++ gcc-interface/utils.c	(working copy)
@@ -963,17 +963,6 @@  add_parallel_type (tree decl, tree paral
   SET_DECL_PARALLEL_TYPE (d, parallel_type);
 }
 
-/* Return the parallel type associated to a type, if any.  */
-
-tree
-get_parallel_type (tree type)
-{
-  if (TYPE_STUB_DECL (type))
-    return DECL_PARALLEL_TYPE (TYPE_STUB_DECL (type));
-  else
-    return NULL_TREE;
-}
-
 /* Utility function of above to merge LAST_SIZE, the previous size of a record
    with FIRST_BIT and SIZE that describe a field.  SPECIAL is true if this
    represents a QUAL_UNION_TYPE in which case we must look for COND_EXPRs and
Index: gcc-interface/lang.opt
===================================================================
--- gcc-interface/lang.opt	(revision 165234)
+++ gcc-interface/lang.opt	(working copy)
@@ -101,10 +101,6 @@  fRTS=
 Ada Joined RejectNegative
 ; Selects the runtime
 
-gdwarf+
-Ada
-; Explicit request for dwarf debug info with GNAT specific extensions.
-
 gant
 Ada Joined Undocumented
 ; Catches typos
Index: gcc-interface/gigi.h
===================================================================
--- gcc-interface/gigi.h	(revision 165250)
+++ gcc-interface/gigi.h	(working copy)
@@ -509,9 +509,6 @@  extern void rest_of_record_type_compilat
 /* Append PARALLEL_TYPE on the chain of parallel types for decl.  */
 extern void add_parallel_type (tree decl, tree parallel_type);
 
-/* Return the parallel type associated to a type, if any.  */
-extern tree get_parallel_type (tree type);
-
 /* Return a FUNCTION_TYPE node.  RETURN_TYPE is the type returned by the
    subprogram.  If it is VOID_TYPE, then we are dealing with a procedure,
    otherwise we are dealing with a function.  PARAM_DECL_LIST is a list of
Index: gcc-interface/trans.c
===================================================================
--- gcc-interface/trans.c	(revision 165253)
+++ gcc-interface/trans.c	(working copy)
@@ -286,18 +286,6 @@  gigi (Node_Id gnat_root, int max_gnat_no
       TYPE_SIZE_UNIT (void_type_node) = size_zero_node;
     }
 
-  /* If the GNU type extensions to DWARF are available, setup the hooks.  */
-#if defined (DWARF2_DEBUGGING_INFO) && defined (DWARF2_GNU_TYPE_EXTENSIONS)
-  /* We condition the name demangling and the generation of type encoding
-     strings on -gdwarf+ and always set descriptive types on.  */
-  if (use_gnu_debug_info_extensions)
-    {
-      dwarf2out_set_type_encoding_func (extract_encoding);
-      dwarf2out_set_demangle_name_func (decode_name);
-    }
-  dwarf2out_set_descriptive_type_func (get_parallel_type);
-#endif
-
   /* Enable GNAT stack checking method if needed */
   if (!Stack_Check_Probes_On_Target)
     set_stack_check_libfunc ("_gnat_stack_check");
Index: gcc-interface/misc.c
===================================================================
--- gcc-interface/misc.c	(revision 165250)
+++ gcc-interface/misc.c	(working copy)
@@ -59,12 +59,6 @@ 
 /* This symbol needs to be defined for the front-end.  */
 void *callgraph_info_file = NULL;
 
-/* How much we want of our DWARF extensions.  Some of our DWARF extensions
-   are incompatible with regular GDB versions, so we must make sure to only
-   produce them on explicit request.  This is eventually reflected into the
-   use_gnu_debug_info_extensions common flag for later processing.  */
-static int gnat_dwarf_extensions = 0;
-
 /* Command-line argc and argv.  These variables are global since they are
    imported in back_end.adb.  */
 unsigned int save_argc;
@@ -139,10 +133,6 @@  gnat_handle_option (size_t scode, const
       flag_eliminate_unused_debug_types = -value;
       break;
 
-    case OPT_gdwarfplus:
-      gnat_dwarf_extensions = 1;
-      break;
-
     case OPT_gant:
       warning (0, "%<-gnat%> misspelled as %<-gant%>");
 
@@ -260,11 +250,6 @@  gnat_post_options (const char **pfilenam
   else
     flag_eliminate_unused_debug_types = 0;
 
-  /* Reflect the explicit request of DWARF extensions into the common
-     flag for use by later passes.  */
-  if (write_symbols == DWARF2_DEBUG)
-    use_gnu_debug_info_extensions = gnat_dwarf_extensions > 0;
-
   optimize = global_options.x_optimize;
   optimize_size = global_options.x_optimize_size;