* gcc-interface/decl.c (gnat_to_gnu_entity) <E_Named_{Integer|Real}>:
	New case to deal with the definition of named numbers.
	<E_Variable>: Minor tweaks.  Set DECL_IGNORED_P on the CONST_DECL
	if a corresponding variable is built.
	* gcc-interface/trans.c (gnat_to_gnu) <N_Integer_Literal>: Return
	error_mark_node instead of aborting on overflow for named numbers.
	<N_Number_Declaration>: Reuse the <N_Object_Declaration> case and
	deal with error_mark_node specifically.
	* gcc-interface/utils.c (create_var_decl): Do not set DECL_IGNORED_P
	on CONST_DECLs.
	(gnat_write_global_declarations): Output global constants.

From-SVN: r276864