Re: [RFC] wifi: iwlwifi: mei: Remove unused flexible-array member in struct iwl_sap_hdr?

From: Johannes Berg
Date: Mon Aug 25 2025 - 04:20:31 EST


On Mon, 2025-08-11 at 17:23 +0900, Gustavo A. R. Silva wrote:
> Hi all,
>
> At first sight, it seems that the flexible-array member `payload`
> in the struct below it's not being used:
>
> drivers/net/wireless/intel/iwlwifi/mei/sap.h:
> 298 /**
> 299 * struct iwl_sap_hdr - prefixes any SAP message
> 300 * @type: See &enum iwl_sap_msg.
> 301 * @len: The length of the message (header not included).
> 302 * @seq_num: For debug.
> 303 * @payload: The payload of the message.
> 304 */
> 305 struct iwl_sap_hdr {
> 306 __le16 type;
> 307 __le16 len;
> 308 __le32 seq_num;
> 309 u8 payload[];
> 310 };
>
> If we remove it, we'd get rid of 14 of the following type of warnings:
>
> drivers/net/wireless/intel/iwlwifi/mei/sap.h:318:28: warning: structure containing a flexible array member is not at the end of another structure
> [-Wflex-array-member-not-at-end]
>
> Is there any case where this array is actually used that I might
> be missing?

Check if it builds? But I don't see it used in our internal (and
possibly more recent) version of this either.

johannes