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From: mjr@hussar.dco.dec.com (Marcus J. Ranum)
Newsgroups: comp.sys.dec
Subject: Re: Unaligned accesses on a DECstation 3100/Ultrix 4.0
Keywords: Disable the alignment fixer?
Message-ID: <1990Nov28.140934.17734@decuac.dec.com>
Date: 28 Nov 90 14:09:34 GMT
References: <11824@spool.cs.wisc.edu>
Sender: news@decuac.dec.com (Network News)
Organization: Digital Equipment Corp., Washington Ultrix Resource Center
Lines: 18

elliott@veronica.cs.wisc.edu (James Elliott) writes:

>Now, my problem is that I want to get >rid< of these unaligned
>accesses, because I consider them bugs.

	Amen! The way I used to catch them (this is GROSS) was by doing
what amounted to a binary search with the debugger. I'd set breakpoints
and slowly home in on it until I isolated it.

	Once I made the mistake of setting a breakpoint:
stop when pc=0xblahblahblah
	and, of course, it sat and thought about it all night.

	There *HAS* to be a better way. Once I caught a similar bug by
porting it to a SPARCStation and running it under the debugger, since
the SS gives you an interrupt.

mjr.