Re: Three if-clauses of constant logic value; char drivers for kernel

From: Willy Tarreau
Date: Fri Dec 29 2006 - 17:17:13 EST

On Tue, Dec 19, 2006 at 09:59:37PM +0100, Mats Erik Andersson wrote:
> Hi there, all masters of kernel code,

Hi !

> I just discovered that the kernel code for contains three
> if-statements that never can change their values, whence they should
> be repaired or eliminated. In source directory linux/drivers/char the
> files vt.c and keyboard.c produce these warning upon compilation:
> vt.c:166: varning: comparison is always false due to limited range
> of data type
> vt.c:289: varning: comparison is always false due to limited range
> of data type
> keyboard.c:640: varning: comparison is always true due to limited
> range of data type
> I did the compilation with gcc 3.3.5 on Debian Sarge. This behaviour
> appeared first for kernel 2.2.19, since I wanted to revive the old
> minirtl edition, but to my surprise the same warnings appear also
> with the brand new kernel

OK thanks for reporting this. I'll take a look at those before next

BTW, sorry, I missed your post. When posting 2.4-related mails, please
try to put the "2.4" word close to the beginning of the subject so that
my eyes can notice it in the middle of the 10000 other montly messages
on LKML.

> Best regards
> Mats Erik Andersson, PhD
> ynglingatal@xxxxxxxx
> mats.andersson64@xxxxxxxxx

best regards,

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