[cairo] crash copying recording surface to PDF surface with tags

[Jonathan Kew]

On 26/12/2020 18:46, Ben Pfaff wrote:
>
> Indeed, when I apply the following, the warning goes away:
>
> diff --git a/src/cairo-recording-surface.c 
> b/src/cairo-recording-surface.c
> index 6df8b0821..1765e7da6 100644
> --- a/src/cairo-recording-surface.c
> +++ b/src/cairo-recording-surface.c
> @@ -1561,6 +1561,7 @@ _cairo_recording_surface_snapshot (void 
> *abstract_other)
>       cairo_status_t status;
>         surface = _cairo_malloc (sizeof (cairo_recording_surface_t));
> +    memset (surface, 0, sizeof (cairo_recording_surface_t));
>       if (unlikely (surface == NULL))
>       return _cairo_surface_create_in_error (_cairo_error 
> (CAIRO_STATUS_NO_MEMORY));
>

This would be better placed after the (surface == NULL) check, otherwise 
it's likely to result in an insta-crash if the allocation failed.

JK