[Ada] Fix undefined symbol for discriminated return type

[Eric Botcazou]

This fixes an undefined symbol at link time in specific cases for functions 
that return a discriminated record type with default discriminant.  It's a 
regression present on the mainline and 5 branch.

Tested on x86_64-suse-linux, applied on the mainline and 5 branch.


2015-06-04  Pierre-Marie de Rodat  <dero...@adacore.com>

        * gcc-interface/decl.c (gnat_to_gnu_entity) <E_Function>: If
        processing a definition, create definitions for padding types
        around return types.


-- 
Eric Botcazou
Index: gcc-interface/decl.c
===================================================================
--- gcc-interface/decl.c	(revision 224054)
+++ gcc-interface/decl.c	(working copy)
@@ -4252,7 +4252,8 @@ gnat_to_gnu_entity (Entity_Id gnat_entit
 		  = maybe_pad_type (gnu_return_type,
 				    max_size (TYPE_SIZE (gnu_return_type),
 					      true),
-				    0, gnat_entity, false, false, false, true);
+				    0, gnat_entity, false, false, definition,
+				    true);
 
 		/* Declare it now since it will never be declared otherwise.
 		   This is necessary to ensure that its subtrees are properly