Re: [Qemu-devel] [PATCH v2 02/15] do_device_add(): look up "device" opts list with qemu_find_opts_err()

[Markus Armbruster <armbru@redhat.com>]

Laszlo Ersek <lersek@redhat.com> writes:

> Conversion status (call chains covered or substituted by error propagation
> marked with square brackets):
>
> do_device_add -> [qemu_find_opts -> error_report]
> do_device_add -> qdev_device_add -> qerror_report
> do_device_add -> qdev_device_add -> qbus_find -> qbus_find_recursive
>   -> qerror_report
> do_device_add -> qdev_device_add -> qbus_find -> qerror_report
> do_device_add -> qdev_device_add -> set_property -> qdev_prop_parse
>   -> qerror_report_err
>
> Signed-off-by: Laszlo Ersek <lersek@redhat.com>
> ---
>  hw/qdev-monitor.c |    7 ++++++-
>  1 files changed, 6 insertions(+), 1 deletions(-)
>
> diff --git a/hw/qdev-monitor.c b/hw/qdev-monitor.c
> index 56d66c3..bbdc90f 100644
> --- a/hw/qdev-monitor.c
> +++ b/hw/qdev-monitor.c
> @@ -590,15 +590,20 @@ void do_info_qdm(Monitor *mon, const QDict *qdict)
>  int do_device_add(Monitor *mon, const QDict *qdict, QObject **ret_data)
>  {
>      Error *local_err = NULL;
> +    QemuOptsList *list;
>      QemuOpts *opts;
>      DeviceState *dev;
>  
> -    opts = qemu_opts_from_qdict(qemu_find_opts("device"), qdict, &local_err);
> +    list = qemu_find_opts_err("device", &local_err);
> +    if (!error_is_set(&local_err)) {
> +        opts = qemu_opts_from_qdict(list, qdict, &local_err);
> +    }
>      if (error_is_set(&local_err)) {
>          qerror_report_err(local_err);
>          error_free(local_err);
>          return -1;
>      }
> +
>      if (!monitor_cur_is_qmp() && qdev_device_help(opts)) {
>          qemu_opts_del(opts);
>          return 0;
       }
       dev = qdev_device_add(opts, &local_err);

/work/armbru/qemu/qdev-monitor.c:667:9: warning: ‘opts’ may be used uninitialized in this function [-Wmaybe-uninitialized]

Not really, of course.  We get here only if local_err is clear, and then
we surely set opts.

Recommend "fix" this warning by dropping this patch.
qemu_find_opts("device") can't fail.  We already assume that elsewhere,
e.g. in drive_init(), balloon_parse(), virtcon_parse(), ...