* gcc-interface/decl.c (gnat_to_gnu_entity) <case E_Record_Subtype>:
	Tidy up.  For a subtype with discriminants and variant part, if a
	variant is statically selected and the fields all have a constant
	position, put them in order of increasing position.  Likewise if
	no variant part but representation clause is present.
	* gcc-interface/utils.c (make_packable_type): Robustify.
	(maybe_pad_type): Use local variable and tidy up condition.  If no
	alignment is specified, use the original one.
	(create_type_stub_decl): Minor tweak.
	(convert) <case VECTOR_CST>: Fix typo.
	<case CONSTRUCTOR>: Deal with padding types around the same type.
	Do not punt on missing fields.
	(unchecked_convert): Call finish_record_type to lay out the special
	record types made for conversions from/to problematic integer types.
	Bump the alignment of CONSTRUCTORs before converting them to a more
	aligned type.

From-SVN: r206796