Path: utzoo!attcan!uunet!snorkelwacker!usc!samsung!emory!hubcap!ncrcae!usceast!yarnall
From: yarnall@usceast.UUCP (Ken Yarnall)
Newsgroups: comp.sys.amiga
Subject: Re: 2091 address zero problems
Summary: No need to yell...
Keywords: Nope nada zip zilch
Message-ID: <3345@usceast.UUCP>
Date: 20 Jul 90 04:36:56 GMT
References: <38936@sequent.UUCP> <3343@usceast.UUCP> <26032@usc.edu>
Organization: Math Department, University of South Carolina (ahem; The USC)
Lines: 44

In article <26032@usc.edu> papa@pollux.usc.edu (Marco Papa) writes:
+In article <3343@usceast.UUCP> yarnall@usceast.UUCP (Ken Yarnall) writes:
+>
+>[...]
+>
+>What he said is that the roms on the 2091 have some inadvertently released
+>debugging software, that sets location zero to a non-NULL value.  He didn't
+>explain to me why his program crashed because of this (which it should not
+>have, IMHO), but he did say that his information came from Commodore.  He was
+>clear in that the problem was in the rom, and not in the filesystem.
+>
+>[...]
+
+Let me put it this way. It is true that the drivers for the A2091 and A590
+do put some debugging stuff (non-zero) at location zero, BUT it is also
+true that the programs that bomb in this situation ARE the culprits. What
+these program do is the following: they use pointers statically un-initialized
+(therefore zero) and READ the value pointed by them, BEFORE initializing
+them....
+
+[...]

You're preaching to the converted, Marco.  I guess I wasn't clear enough in
what I wrote above.  I *know* what causes programs with uninitialized
pointers to crash, have seen the symptoms, and have even spent hours
ferreting out bugs of this nature.  When I said I would have liked the guy at
New Horizons to explain why his program crashed because of this, what I meant
was "Why did you release a commercial program (which sports a `bug-free'
guarentee!) with a bug like this?"

Everyone is to blame here.  I think it is clear from what I said that I feel
the software developers should be more careful (you never catch me using
uninitialized pointers -- no way, man, never! ;^), but there doesn't seem to
me to be much of an excuse for C= to be releasing *roms* with active
diagnostic code in them.  Let me say, though, that Commodore has been very
forthright about explaining what went wrong, and providing work-arounds.

+-- Marco

kenny
-- 
         Ken Yarnall                 ///   yarnall@cs.scarolina.EDU
          Math Department, USC   \\\///   yarnall@ucseast.UUCP
           Columbia, S.C. 29208   \\\/   (803)777-6686