Re: [PATCH] checkpatch: prefer = {} initializations to = {0}

From: Julia Lawall
Date: Thu Aug 05 2021 - 14:18:00 EST




On Thu, 5 Aug 2021, Joe Perches wrote:

> On Thu, 2021-08-05 at 05:27 -0700, Joe Perches wrote:
> > On Thu, 2021-08-05 at 13:43 +0300, Dan Carpenter wrote:
> > > The "= {};" style empty struct initializer is preferred over = {0}.
> > > It avoids the situation where the first struct member is a pointer and
> > > that generates a Sparse warning about assigning using zero instead of
> > > NULL. Also it's just nicer to look at.
>
> Perhaps a cocci script like the below could help too:
>
> $ cat zero_init_struct.cocci
> @@
> identifier name;
> identifier t;
> @@
>
> struct name t = {
> - 0
> };
>
> @@
> identifier name;
> identifier t;
> identifier member;
> @@
>
> struct name t = {
> ...,
> .member = {
> - 0
> },
> ...,
> };

My test turns up over 1900 occurrences. There is the question of whether
{} or { } is preferred. The above semantic patch replaces {0} by {} and
( 0 } by { }.

julia