Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1a 7/7/83; site rlgvax.UUCP
Path: utzoo!linus!decvax!harpo!seismo!rlgvax!guy
From: guy@rlgvax.UUCP (Guy Harris)
Newsgroups: net.lang.c
Subject: Re: Breaking out of labeled statements - (nf)
Message-ID: <1084@rlgvax.UUCP>
Date: Wed, 31-Aug-83 20:07:30 EDT
Article-I.D.: rlgvax.1084
Posted: Wed Aug 31 20:07:30 1983
Date-Received: Thu, 1-Sep-83 20:32:52 EDT
References: <2672@uiucdcs.UUCP>,  <1799@allegra.UUCP>
Organization: CCI Office Systems Group, Reston, VA
Lines: 28

"goto"s can be used for treating several cases as subcases of one common
case (i.e., do the case-specific thing and then the common actions), generally
without too tangled code.  Furthermore, if it *does* tangle things, or you don't
want to use "goto"s, many versions of the C "final" optimizer will do the right
thing if you write something like

	case (foo) {

	case 1:
		/* 1-specific things */
		/* common code */
		break;

	case 2:
		/* 2-specific things */
		/* common code */
		break;

		.
		.
		.

and join the common code and stick a jump/branch instruction into the cases.
(Versions known to: PDP-11, VAX-11, Zilog "Zeus", CCI - and probably most
other - 68000).

	Guy Harris
	{seismo,mcnc,we13,brl-bmd,allegra}!rlgvax!guy