Re: [PATCH] md: do not use ++ in rcu_dereference() argument

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Sunday 05 September 2010 20:32:18 Kulikov Vasiliy wrote:
> From: Vasiliy Kulikov <segooon@xxxxxxxxx>
> 
> rcu_dereference() is macro, so it might use its argument twice.
> Argument must not has side effects.
> 
> It was found by compiler warning:
> drivers/md/raid1.c: In function ‘read_balance’:
> drivers/md/raid1.c:445: warning: operation on ‘new_disk’ may be undefined

I think the rcu_dereference macro should really not evaluate its argument
twice, and I don't see where it does.
As a general rule, we try to write macros in Linux such that they behave
like functions and don't have surprising side-effects.

Which kernel and gcc version do you see the warning with?

	Arnd
--
To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Kernel Development]     [Kernel Announce]     [Kernel Newbies]     [Linux Networking Development]     [Share Photos]     [IDE]     [Security]     [Git]     [Netfilter]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Device Mapper]

  Powered by Linux