unaligned data access - Ultrix 3.0 (RISC)

[Jeff Michaud]

In article <2678 at decuac.DEC.COM>, chris at winsrf.dec.com (Chris Cordrey) writes:
> > "Fixed up unaligned data access for pid XXXXXXX (proc_name) at pc 0xNNNNNN"
> see nac(1) for more info on how to shut off the messages.

	That should be uac(1).  There is also a system call you can use to change it
	though I forget it's name at this time (it may be a syscall(2)).

> (an obvious
> performance hit which you can fix by aligning the offending variables
> in your source - the trick is finding them!)

	Finding them is pretty easy.  dbx the offending program, then

		dbx> 0xNNNNNN/10i

	will tell you the routine-name:linenumber of the offending source line.

> VAXen are more forgiving in this area.

	Yes, but you take the performance hit in the microcode instead :-)
-- 
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|Jeff Michaud    michaud at decwrl.dec.com  michaud at decvax.dec.com|
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