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From: "Henning P. Schmiedehausen" <mailgate@hometree.net>
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Subject: Re: [IDEA+RFC] Possible solution for min()/max() war
Date: Tue, 28 Aug 2001 15:44:53 +0000 (UTC)
Organization: INTERMETA - Gesellschaft fuer Mehrwertdienste mbH
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Linus Torvalds <torvalds@transmeta.com> writes:

>I'll show you a real example from drivers/acorn/scsi/acornscsi.c:

>	min(host->scsi.SCp.this_residual, DMAC_BUFFER_SIZE / 2);

>this_residual is "int", and "DMAC_BUFFER_SIZE" is just a #define for
>an integer constant. So the above is actually a signed comparison, and
>I'll bet you that was not what the author intended.

And the mistake of the author was not to write "unsigned int this_residual".
That's the bug. Not the min() function.

	Regards
		Henning

-- 
Dipl.-Inf. (Univ.) Henning P. Schmiedehausen       -- Geschaeftsfuehrer
INTERMETA - Gesellschaft fuer Mehrwertdienste mbH     hps@intermeta.de

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