Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site peora.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!vax135!petsd!peora!jer From: jer@peora.UUCP (J. Eric Roskos) Newsgroups: net.arch Subject: Re: Re: Where to do stack checking, etc. Message-ID: <1656@peora.UUCP> Date: Thu, 19-Sep-85 08:03:46 EDT Article-I.D.: peora.1656 Posted: Thu Sep 19 08:03:46 1985 Date-Received: Fri, 20-Sep-85 06:06:59 EDT References: <796@kuling.UUCP> <1713@orca.UUCP> <1599@peora.UUCP> <335@ihlpl.UUCP> <2384@uvacs.UUCP> Organization: Perkin-Elmer SDC, Orlando, Fl. Lines: 18 > I'm still looking for a machine that will trap references to uninitialized > data. This is a hard problem. My dissertation advisor (R. I. Winner) did a good bit of research on this problem; see, for example, Winner, R. I., "Unassigned Objects," ACM TOPLAS, October, 1984. The problem is that either you have to have a unique bit pattern representing unassigned data (which means there's one value that has a special meaning), or you have to have a tag bit denoting "unassigned". Various interesting models of memory are possible if you generalize the unassigned object. -- Shyy-Anzr: J. Eric Roskos UUCP: Ofc: ..!{decvax,ucbvax,ihnp4}!vax135!petsd!peora!jer Home: ..!{decvax,ucbvax,ihnp4}!vax135!petsd!peora!jerpc!jer US Mail: MS 795; Perkin-Elmer SDC; 2486 Sand Lake Road, Orlando, FL 32809-7642 Brought to you by Super Global Mega Corp .com