diff --git a/gcc/ada/adaint.h b/gcc/ada/adaint.h
index ebf99a59bd8..542b1c12cf9 100644
--- a/gcc/ada/adaint.h
+++ b/gcc/ada/adaint.h
@@ -78,6 +78,8 @@ extern OS_Time __gnat_file_time_fd                  (int);
 extern void   __gnat_set_file_time_name		   (char *, time_t);
 extern void   __gnat_get_env_value_ptr             (char *, int *,
 						    char **);
+extern int    __gnat_dup			   (int);
+extern int    __gnat_dup2			   (int, int);
 extern int    __gnat_file_exists		   (char *);
 extern int    __gnat_is_regular_file               (char *);
 extern int    __gnat_is_absolute_path              (char *,int);
diff --git a/gcc/ada/misc.c b/gcc/ada/misc.c
index 6e871b565c4..8c444217759 100644
--- a/gcc/ada/misc.c
+++ b/gcc/ada/misc.c
@@ -94,7 +94,6 @@ static bool gnat_post_options		(const char **);
 static HOST_WIDE_INT gnat_get_alias_set	(tree);
 static void gnat_print_decl		(FILE *, tree, int);
 static void gnat_print_type		(FILE *, tree, int);
-static int gnat_types_compatible_p	(tree, tree);
 static const char *gnat_printable_name	(tree, int);
 static tree gnat_eh_runtime_type	(tree);
 static int gnat_eh_type_covers		(tree, tree);
@@ -130,6 +129,8 @@ static tree gnat_type_max_size		(tree);
 #define LANG_HOOKS_PUSHDECL		lhd_return_tree
 #undef  LANG_HOOKS_FINISH_INCOMPLETE_DECL
 #define LANG_HOOKS_FINISH_INCOMPLETE_DECL gnat_finish_incomplete_decl
+#undef	LANG_HOOKS_REDUCE_BIT_FIELD_OPERATIONS
+#define LANG_HOOKS_REDUCE_BIT_FIELD_OPERATIONS true
 #undef  LANG_HOOKS_GET_ALIAS_SET
 #define LANG_HOOKS_GET_ALIAS_SET	gnat_get_alias_set
 #undef  LANG_HOOKS_EXPAND_EXPR
@@ -142,8 +143,6 @@ static tree gnat_type_max_size		(tree);
 #define LANG_HOOKS_PRINT_DECL		gnat_print_decl
 #undef  LANG_HOOKS_PRINT_TYPE
 #define LANG_HOOKS_PRINT_TYPE		gnat_print_type
-#undef  LANG_HOOKS_TYPES_COMPATIBLE_P
-#define LANG_HOOKS_TYPES_COMPATIBLE_P	gnat_types_compatible_p
 #undef  LANG_HOOKS_TYPE_MAX_SIZE
 #define LANG_HOOKS_TYPE_MAX_SIZE	gnat_type_max_size
 #undef  LANG_HOOKS_DECL_PRINTABLE_NAME
@@ -554,27 +553,6 @@ gnat_print_type (FILE *file, tree node, int indent)
     }
 }
 
-/* We consider two types compatible if they have the same main variant,
-   but we also consider two array types compatible if they have the same
-   component type and bounds.
-
-   ??? We may also want to generalize to considering lots of integer types
-   compatible, but we need to understand the effects of alias sets first.  */
-
-static int
-gnat_types_compatible_p (tree x, tree y)
-{
-  if (TREE_CODE (x) == ARRAY_TYPE && TREE_CODE (y) == ARRAY_TYPE
-      && gnat_types_compatible_p (TREE_TYPE (x), TREE_TYPE (y))
-      && operand_equal_p (TYPE_MIN_VALUE (TYPE_DOMAIN (x)),
-			  TYPE_MIN_VALUE (TYPE_DOMAIN (y)), 0)
-      && operand_equal_p (TYPE_MAX_VALUE (TYPE_DOMAIN (x)),
-			  TYPE_MAX_VALUE (TYPE_DOMAIN (y)), 0))
-    return 1;
-  else
-    return TYPE_MAIN_VARIANT (x) == TYPE_MAIN_VARIANT (y);
-}
-
 static const char *
 gnat_printable_name (tree decl, int verbosity)
 {
diff --git a/gcc/ada/trans.c b/gcc/ada/trans.c
index 162e6acc198..2acf8323849 100644
--- a/gcc/ada/trans.c
+++ b/gcc/ada/trans.c
@@ -1621,7 +1621,9 @@ call_to_gnu (Node_Id gnat_node, tree *gnu_result_type_p, tree gnu_target)
        gnat_formal = Next_Formal_With_Extras (gnat_formal),
        gnat_actual = Next_Actual (gnat_actual))
     {
-      tree gnu_formal_type = gnat_to_gnu_type (Etype (gnat_formal));
+      tree gnu_formal
+	= (present_gnu_tree (gnat_formal)
+	   ? get_gnu_tree (gnat_formal) : NULL_TREE);
       /* We treat a conversion between aggregate types as if it is an
 	 unchecked conversion.  */
       bool unchecked_convert_p
@@ -1632,10 +1634,8 @@ call_to_gnu (Node_Id gnat_node, tree *gnu_result_type_p, tree gnu_target)
 			   ? Expression (gnat_actual) : gnat_actual);
       tree gnu_name = gnat_to_gnu (gnat_name);
       tree gnu_name_type = gnat_to_gnu_type (Etype (gnat_name));
-      tree gnu_formal
-	= (present_gnu_tree (gnat_formal)
-	   ? get_gnu_tree (gnat_formal) : NULL_TREE);
       tree gnu_actual;
+      tree gnu_formal_type;
 
       /* If it's possible we may need to use this expression twice, make sure
 	 than any side-effects are handled via SAVE_EXPRs. Likewise if we need
@@ -1739,9 +1739,6 @@ call_to_gnu (Node_Id gnat_node, tree *gnu_result_type_p, tree gnu_target)
 	gnu_actual = convert (gnat_to_gnu_type (Etype (gnat_actual)),
 			      gnu_actual);
 
-      if (TREE_CODE (gnu_actual) != SAVE_EXPR)
-	gnu_actual = convert (gnu_formal_type, gnu_actual);
-
       /* If we have not saved a GCC object for the formal, it means it is an
 	 OUT parameter not passed by reference and that does not need to be
 	 copied in. Otherwise, look at the PARM_DECL to see if it is passed by
@@ -1856,9 +1853,7 @@ call_to_gnu (Node_Id gnat_node, tree *gnu_result_type_p, tree gnu_target)
 					    integer_zero_node),
 				   false);
 	  else
-	    gnu_actual
-	      = convert (TYPE_MAIN_VARIANT (DECL_ARG_TYPE (gnu_formal)),
-			 gnu_actual);
+	    gnu_actual = convert (DECL_ARG_TYPE (gnu_formal), gnu_actual);
 	}
 
       gnu_actual_list = tree_cons (NULL_TREE, gnu_actual, gnu_actual_list);
@@ -2244,8 +2239,15 @@ Exception_Handler_to_gnu_sjlj (Node_Id gnat_node)
       else if (Nkind (gnat_temp) == N_Identifier
 	       || Nkind (gnat_temp) == N_Expanded_Name)
 	{
-	  tree gnu_expr
-	    = gnat_to_gnu_entity (Entity (gnat_temp), NULL_TREE, 0);
+	  Entity_Id gnat_ex_id = Entity (gnat_temp);
+	  tree gnu_expr;
+
+	  /* Exception may be a renaming. Recover original exception which is
+	     the one elaborated and registered.  */
+	  if (Present (Renamed_Object (gnat_ex_id)))
+	    gnat_ex_id = Renamed_Object (gnat_ex_id);
+
+	  gnu_expr = gnat_to_gnu_entity (gnat_ex_id, NULL_TREE, 0);
 
 	  this_choice
 	    = build_binary_op