From owner-freebsd-current  Tue Nov 16  6:22:42 1999
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Date: Tue, 16 Nov 1999 09:22:28 -0500 (EST)
From: Garrett Wollman <wollman@khavrinen.lcs.mit.edu>
Message-Id: <199911161422.JAA10973@khavrinen.lcs.mit.edu>
To: Bruce Evans <bde@zeta.org.au>
Cc: Pierre Beyssac <beyssac@enst.fr>,
	Garrett Wollman <wollman@khavrinen.lcs.mit.edu>,
	Sheldon Hearn <sheldonh@uunet.co.za>, freebsd-current@FreeBSD.ORG
Subject: Re: egcs -O breaks ping.c:in_cksum()
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<<On Tue, 16 Nov 1999 15:17:43 +1100 (EST), Bruce Evans <bde@zeta.org.au> said:

> Perhaps the above should be written as:

> 		sum += ntohs(*(u_char *)w << 8);

> to avoid the undefined union access (answer.us).

No.  The IP checksum is defined in a manner which is
endian-independent.  Adding calls to ntohs() would only confuse
matters further.

-GAWollman

--
Garrett A. Wollman   | O Siem / We are all family / O Siem / We're all the same
wollman@lcs.mit.edu  | O Siem / The fires of freedom 
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MIT, LCS, CRS, or NSA|                     - Susan Aglukark and Chad Irschick


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