From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <88457fd0236630c32e5a94bfbad89fd7@vitanuova.com>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] how to avoid a memset() optimization
From: rog@vitanuova.com
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Date: Wed, 13 Nov 2002 13:55:05 +0000
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> For one thing, it doesn't work (unless you force
> volatile qualification within secmemset)

which seems reasonable to me.

and for barely more runtime cost, one could define:

void*
secmemset(void *ap, int c, ulong n)
{
	memset((volatile void *)ap, c, n);
}

(or is that "void * volatile"?  i never sussed this C type qualifier
stuff).

is that not sufficient to stymie any legitimate optimisations that GCC
might try to do, while maintaining comparable performance?

(not to mention making sure that you don't kill the performance of any
crypto tight loops that might be running on the original buffer by
declaring it volatile).

  cheers,
    rog.