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From: David Laight <David.Laight@ACULAB.COM>
To: "'Rustad, Mark D'" <mark.d.rustad@intel.com>
CC: Marcel Holtmann <marcel@holtmann.org>,
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Subject: RE: [GIT] Networking
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Date: Mon, 7 Sep 2015 11:02:59 +0000
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From: Rustad, Mark D
...
> >> static int smp_ah(struct crypto_blkcipher *tfm, const u8 irk[16],
> >>                  const u8 r[3], u8 res[3])
> >
> > Expect that it looks like you are passing arrays by value,
> > but instead you are passing by reference.
> >
> > Explicitly pass by reference and sizeof works.
> 
> It depends on what you mean by works. It at least doesn't look so misleading when passing by reference
> and so works more as expected. The sizeof in either case will never return the size of the array. To
> have sizeof return the size of the array would require a typedef of the array to pass by reference. In
> some cases that could be the right thing to do.

Feed:
int bar(int (*f)[10]) { return sizeof *f; }
into cc -O2 -S and look at the generated code - returns 40 not 4.

	David