Re: [Qemu-devel] [PATCH 08/26] qapi: Generate a nicer struct for flat unions

[Eric Blake]

On 08/04/2015 03:17 AM, Markus Armbruster wrote:
> The struct generated for a flat union is weird: the members of its
> base are at the end, except for the union tag, which is at the
> beginning.
> 

> Change to put all base members at the beginning, unadulterated.  Not
> only is this easier to understand, it also permits casting the flat
> union to its base, if that should become useful.

And I already have a followup patch to your RFCv3 where it IS useful :)

> 
> We now generate:
> 
>     struct UserDefFlatUnion
>     {
>         /* Members inherited from UserDefUnionBase: */
>         char *string;
>         EnumOne enum1;
>         /* Own members: */
>         union { /* union tag is @enum1 */
>             void *data;
>             UserDefA *value1;
>             UserDefB *value2;
>             UserDefB *value3;
>         };
>     };
> 
> Signed-off-by: Markus Armbruster <address@hidden>
> ---
>  scripts/qapi-types.py | 38 ++++++++++++++++++++++----------------
>  1 file changed, 22 insertions(+), 16 deletions(-)
> 

Reviewed-by: Eric Blake <address@hidden>

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org

signature.asc
Description: OpenPGP digital signature