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

From: Joe Perches
Date: Thu Aug 05 2021 - 14:28:20 EST


On Thu, 2021-08-05 at 20:17 +0200, Julia Lawall wrote:
> 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 { }.

I saw that and I don't recall how to force one style or another
to be output.