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Date: Thu, 22 Jun 2017 09:59:10 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Arnd Bergmann <arnd@arndb.de>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Anna-Maria Gleixner <anna-maria@linutronix.de>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] rcu: remove unused variable in boot_cpu_state_init
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So, to continue this side thought about uninitialized_var(), it is dangerous 
because the following buggy pattern does not generate a compiler warning:

        long uninitialized_var(error);

	...

        if (error)
                return error;


... and still there are over 290 uses of uninitialized_var() in the kernel - and 
any of them could turn into a silent but real uninitialized variable bugs due to 
subsequent changes.

Thanks,

	Ingo