[PATCH wayland] scanner: don't emit the extern declarations for external types

[Bryce Harrington]

On Fri, May 29, 2015 at 11:35:05AM +0300, Pekka Paalanen wrote:
> On Thu, 28 May 2015 19:30:33 +0300
> Giulio Camuffo <giuliocamuffo at gmail.com> wrote:
> 
> > We were emitting the extern declarations of all types used in the protocol,
> > even if not defined in it. This caused warnings to be produced when using
> > the -Wredundant-decls compiler flag when building an extension that uses
> > e.g. wl_surface. However we only need the extern declarations if the
> > protocol defines a factory for those external interfaces. That is a
> > bad design and can be however done by including the dependent protocol
> > header first.
> > So only emit the extern declarations for the types that the protocol
> > actually defines, this restoring the behavior we were using in 1.7.
> > 
> > Fixes https://bugs.freedesktop.org/show_bug.cgi?id=90677
> > ---
> >  src/scanner.c | 10 +++-------
> >  1 file changed, 3 insertions(+), 7 deletions(-)
> > 
> > diff --git a/src/scanner.c b/src/scanner.c
> > index 11efffc..4ab7d85 100644
> > --- a/src/scanner.c
> > +++ b/src/scanner.c
> > @@ -1089,18 +1089,14 @@ emit_header(struct protocol *protocol, enum side side)
> >  		printf("struct %s;\n", *p);
> >  		prev = *p;
> >  	}
> > +	wl_array_release(&types);
> >  	printf("\n");
> >  
> > -	prev = NULL;
> > -	wl_array_for_each(p, &types) {
> > -		if (prev && strcmp(*p, prev) == 0)
> > -			continue;
> > +	wl_list_for_each(i, &protocol->interface_list, link) {
> >  		printf("extern const struct wl_interface "
> > -		       "%s_interface;\n", *p);
> > -		prev = *p;
> > +		       "%s_interface;\n", i->name);
> >  	}
> >  
> > -	wl_array_release(&types);
> >  	printf("\n");
> >  
> >  	wl_list_for_each(i, &protocol->interface_list, link) {
> 
> I diffed all the Weston's generated protocol files before and after
> this patch, and the result is good.
> 
> Reviewed-by: Pekka Paalanen <pekka.paalanen at collabora.co.uk>
> 
> This patch can land once we get a Tested-by from rawoul.
> 
> Bryce, could you hold off with 1.8.0 until this patch has landed?

Yes.

> I think this is important to have in 1.8.0, because releasing the core
> headers change now and adding this fix later might theoretically break
> users.
> 
> 
> Thanks,
> pq