* libbfd-in.h (struct artdata): Add extended_names_size field.

	* libbfd-in.h (struct artdata): Add extended_names_size field.
	* libbfd.h: Rebuilt.
	* coff-rs600.c (_bfd_xcoff_archive_p): Don't clear fields in freshly
	allocated object by bfd_zalloc.
	* coff64-rs6000.c (xcoff64_archive_p): Likewise.
	* ecoff.c (_bfd_ecoff_archive_p): Likewise.
	* archive.c (_bfd_generic_mkarchive, bfd_generic_archive_p): Likewise.
	(get_extended_arelt_filename): Fail if index is bigger or equal to
	extended_names_size.
	(_bfd_generic_read_ar_hdr_mag): Don't set bfd_error_malformed_archive,
	get_extended_arelt_filename already did that.
	(_bfd_slurp_extended_name_table): Initialize extended_names_size field.
	Allocate one extra byte and clear it, in case extended names table
	is not terminated.