re PR debug/78191 (ICE in calc_die_sizes)

re PR debug/78191 (ICE in calc_die_sizes)

	* dwarf2out.c (size_of_discr_list): Fix typo in function comment.

	PR debug/78191
	* dwarf2out.c (abbrev_opt_base_type_end): New variable.
	(die_abbrev_cmp): Sort dies with die_abbrev smaller than
	abbrev_opt_base_type_end only by increasing die_abbrev, before
	any other dies.
	(optimize_abbrev_table): Don't change abbrev numbers of
	base types and CU or optimize implicit consts in them if
	calc_base_type_die_sizes has been called during build_abbrev_table.
	(calc_base_type_die_sizes): If abbrev_opt_start, set
	abbrev_opt_base_type_end to one plus largest base type's
	die_abbrev.

From-SVN: r242606