Re: [Outreachy kernel] Re: [PATCH v1 1/5] staging: wfx: fix warnings of no space is necessary

[Joe Perches <joe@perches.com>]

On Sun, 2019-10-20 at 21:52 +0200, Julia Lawall wrote:
> On Sun, 20 Oct 2019, Joe Perches wrote:
[]
> > There's probably a generic cocci mechanism to check function
> > prototypes and then remove uses of unnecessary void pointer casts
> > in function calls.  I'm not going to try to figure out that syntax.
> 
> With the --recursive-includes option, perhaps:
> 
> @r@
> identifier f;
> parameter list[n] ps;
> type T;
> identifier i;
> @@
> 
> T f(ps, void *i, ...);
> 
> @@
> expression e;
> identifier r.f;
> expression list[r.n] es;
> @@
> 
> f(es,
> - (void *)(e)
> + e
>   ,...)
> 
> This of course only works for functions that have prototypes, and not for
> macros.  It will also run slowly.

You are not kidding about slow, but it doesn't seem to work
for mem<foo>, maybe because system includes aren't analyzed.

Single file processing time on an XPS13 averages more than
100 seconds per file.

Also:

	expression e;

could probably be better as:

	type T;
	T *p;

as some of the expressions cast to void are int or size_t
and it's probably better to restrict the conversions to
just pointer or array types.