Re: [PATCH v2] for_each_string_list_item: avoid undefined behavior for empty list

From: Andreas Schwab <schwab@linux-m68k.org>
Date: Sep 20, 2017, 16:28 UTC
Message-ID: <87vakd2v22.fsf@linux-m68k.org>
In-Reply-To: <20170920052705.GC126984@aiede.mtv.corp.google.com>

On Sep 19 2017, Jonathan Nieder <jrnieder@gmail.com> wrote:

Show 12 quoted lines

> B. #define for_each_string_list_item(item, list) \
> 	if (list->items) \
> 		for (item = ...; ...; ... )
>
>    This breaks a caller like
> 	if (foo)
> 		for_each_string_list_item(item, list)
> 			...
> 	else
> 		...
>
>    making it a non-starter.

That can be fixed with a dangling else.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
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