Re: [PATCH 2/3] nodemask.h: Fix compilation error with GCC12

From: Peter Zijlstra <peterz@infradead.org>
To: Christophe de Dinechin <dinechin@redhat.com>
Cc: trivial@kernel.org, Ben Segall <bsegall@google.com>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Steven Rostedt <rostedt@goodmis.org>,
	Ingo Molnar <mingo@redhat.com>, Mel Gorman <mgorman@suse.de>,
	Dietmar Eggemann <dietmar.eggemann@arm.com>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Daniel Bristot de Oliveira <bristot@redhat.com>,
	Jason Wang <jasowang@redhat.com>,
	virtualization@lists.linux-foundation.org,
	linux-kernel@vger.kernel.org,
	Zhen Lei <thunder.leizhen@huawei.com>,
	Juri Lelli <juri.lelli@redhat.com>
Subject: Re: [PATCH 2/3] nodemask.h: Fix compilation error with GCC12
Date: Thu, 14 Apr 2022 17:23:25 +0200	[thread overview]
Message-ID: <Ylg8baQjQTkrnnD9@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20220414150855.2407137-3-dinechin@redhat.com>

On Thu, Apr 14, 2022 at 05:08:54PM +0200, Christophe de Dinechin wrote:

> diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h
> index 567c3ddba2c4..c6199dbe2591 100644
> --- a/include/linux/nodemask.h
> +++ b/include/linux/nodemask.h
> @@ -375,14 +375,13 @@ static inline void __nodes_fold(nodemask_t *dstp, const nodemask_t *origp,
>  }
>  
>  #if MAX_NUMNODES > 1
> -#define for_each_node_mask(node, mask)			\
> -	for ((node) = first_node(mask);			\
> -		(node) < MAX_NUMNODES;			\
> -		(node) = next_node((node), (mask)))
> +#define for_each_node_mask(node, mask)				    \
> +	for ((node) = first_node(mask);				    \
> +	     (node >= 0) && (node) < MAX_NUMNODES;		    \
> +	     (node) = next_node((node), (mask)))
>  #else /* MAX_NUMNODES == 1 */
> -#define for_each_node_mask(node, mask)			\
> -	if (!nodes_empty(mask))				\
> -		for ((node) = 0; (node) < 1; (node)++)
> +#define for_each_node_mask(node, mask)                                  \
> +	for ((node) = 0; (node) < 1 && !nodes_empty(mask); (node)++)
>  #endif /* MAX_NUMNODES */

Again, less readable code :/ And why?