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Date: Tue, 28 Aug 2001 19:28:43 +0200
From: Roman Zippel <zippel@linux-m68k.org>
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To: "Bill Rugolsky Jr." <rugolsky@ead.dsa.com>
CC: Andreas Schwab <schwab@suse.de>, Linus Torvalds <torvalds@transmeta.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [IDEA+RFC] Possible solution for min()/max() war
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Hi,

"Bill Rugolsky Jr." wrote:

> > Ok, it uses an assignment, but it has almost the same effect (except for
> > pointer/integer values).
> 
> Wrong.  A cast throws away information, making meaningful warnings impossible.
> The assignment allows the compiler to apply the usual C integral
> promotions and catch narrowing and non-value-preserving conversions,
> like unsigned int to int, or an even more common bug, unsigned int to
> long, which behaves differently depending on whether long is 32 or 64
> bits.

Do you have an example? AFAIK this can only be done for constants and
mosts constants used with min are within usual integer limits.

bye, Roman