On Fri, Mar 28, 2025 at 08:45:32AM -0600, Gustavo A. R. Silva wrote:
> -Wflex-array-member-not-at-end was introduced in GCC-14, and we are
> getting ready to enable it, globally.
>
> Use the `DEFINE_RAW_FLEX()` helper for an on-stack definition of
> a flexible structure where the size of the flexible-array member
> is known at compile-time, and refactor the rest of the code,
> accordingly.
>
> So, with these changes, fix the following warning:
>
> drivers/gpu/drm/nouveau/nvif/outp.c:199:45: warning: structure containing a
> flexible array member is not at the end of another structure
> [-Wflex-array-member-not-at-end]
>
> Signed-off-by: Gustavo A. R. Silva <gustavo...@kernel.org>
> ---
> drivers/gpu/drm/nouveau/nvif/outp.c | 16 +++++++---------
> 1 file changed, 7 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/drm/nouveau/nvif/outp.c
> b/drivers/gpu/drm/nouveau/nvif/outp.c
> index 6daeb7f0b09b..403cf16d5e84 100644
> --- a/drivers/gpu/drm/nouveau/nvif/outp.c
> +++ b/drivers/gpu/drm/nouveau/nvif/outp.c
> @@ -195,20 +195,18 @@ nvif_outp_dp_aux_pwr(struct nvif_outp *outp, bool
> enable)
> int
> nvif_outp_hda_eld(struct nvif_outp *outp, int head, void *data, u32 size)
> {
> - struct {
> - struct nvif_outp_hda_eld_v0 mthd;
> - u8 data[128];
> - } args;
> + DEFINE_RAW_FLEX(struct nvif_outp_hda_eld_v0, mthd, data, 128);
> int ret;
>
> - if (WARN_ON(size > ARRAY_SIZE(args.data)))
> + if (WARN_ON(size > 128))
Seems a bit unfortunate that the size is duplicated here.
Can we have an accessor macro to derive the size for us?
union {
u8 bytes[struct_size_t(type, member, count)];
type obj;
} name##_u initializer;
Maybe a macro that returns the size difference between bytes and obj?
> return -EINVAL;
>
> - args.mthd.version = 0;
> - args.mthd.head = head;
> + mthd->version = 0;
> + mthd->head = head;
>
> - memcpy(args.data, data, size);
> - ret = nvif_mthd(&outp->object, NVIF_OUTP_V0_HDA_ELD, &args,
> sizeof(args.mthd) + size);
> + memcpy(mthd->data, data, size);
> + ret = nvif_mthd(&outp->object, NVIF_OUTP_V0_HDA_ELD, mthd,
> + __struct_size(mthd) + size);
> NVIF_ERRON(ret, &outp->object, "[HDA_ELD head:%d size:%d]", head, size);
> return ret;
> }
> --
> 2.43.0
>
