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SubjectRe: [PATCH] sched: fix never executed code due to expression always false
Jesper Juhl wrote:
> On Fri, 15 Apr 2005, Nick Piggin wrote:
>
>
>>Jesper Juhl wrote:
>>
>>>There are two expressions in kernel/sched.c that are always false since they
>>>test for <0 but the result of the expression is unsigned so they will never
>>>be less than zero. This patch implement the logic that I believe is intended
>>>without the signedness issue and without the nasty casts.
>>><disclaimer>patch is compile tested only</disclaimer>
>>>
>>This is not *quite* the intended behaviour. It is OK for prev->timestamp
>>to be '0 - a bit' and now to be '0 + a bit' in the case of wrapping.
>>
>>Although considering they're 64-bit values, I'm not sure how much we care.
>>
>
> How do you propose to fix this then? As the code is now the expressionsa
> are always false - should we just remove the them? Or do you have a
> sensible definition of "a bit" ? or ome other suggestion alltogether?
>

Make it a signed comparison?

--
SUSE Labs, Novell Inc.


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