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

Andreas Schwab [off-list ref] writes:

On Sep 20 2017, Jonathan Nieder [off-list ref] wrote:

quoted

Andreas Schwab wrote:

quoted

On Sep 19 2017, Jonathan Nieder [off-list ref] wrote:

quoted

quoted

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.

I believe the fix you're referring to is option C, from the same email
you are replying to.  If not, please correct me.

A variant thereof, yes.

Now you make me curious.  How would that variant be different from
option C. in Jonathan's message?  Perhaps that different version may
be a solution to work around the potential issue mentioned in the
description of option C.?