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

[Pekka Paalanen]

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?
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