scsi: hisi_sas: Avoid a couple -Wflex-array-member-not-at-end warnings

[PATCH][next] scsi: hisi_sas: Avoid a couple -Wflex-array-member-not-at-end warnings

Posted by Gustavo A. R. Silva 3 months ago

-Wflex-array-member-not-at-end was introduced in GCC-14, and we are
getting ready to enable it, globally.

Move the conflicting declarations to the end of the corresponding
structures (and in a union). Notice that `struct ssp_command_iu`
is a flexible structure, this is a structure that contains a
flexible-array member.

With these changes fix the following warnings:

drivers/scsi/hisi_sas/hisi_sas.h:639:38: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]
drivers/scsi/hisi_sas/hisi_sas.h:616:47: 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 <gustavoars@kernel.org>
---
 drivers/scsi/hisi_sas/hisi_sas.h | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/hisi_sas/hisi_sas.h b/drivers/scsi/hisi_sas/hisi_sas.h
index 1323ed8aa717..55c638dd58b1 100644
--- a/drivers/scsi/hisi_sas/hisi_sas.h
+++ b/drivers/scsi/hisi_sas/hisi_sas.h
@@ -613,8 +613,8 @@ struct hisi_sas_command_table_ssp {
 	struct ssp_frame_hdr hdr;
 	union {
 		struct {
-			struct ssp_command_iu task;
 			u32 prot[PROT_BUF_SIZE];
+			struct ssp_command_iu task;
 		};
 		struct ssp_tmf_iu ssp_task;
 		struct xfer_rdy_iu xfer_rdy;
@@ -636,13 +636,17 @@ struct hisi_sas_status_buffer {
 
 struct hisi_sas_slot_buf_table {
 	struct hisi_sas_status_buffer status_buffer;
-	union hisi_sas_command_table command_header;
 	struct hisi_sas_sge_page sge_page;
+
+	/* Must be last --ends in a flexible-array member. */
+	union hisi_sas_command_table command_header;
 };
 
 struct hisi_sas_slot_dif_buf_table {
-	struct hisi_sas_slot_buf_table slot_buf;
 	struct hisi_sas_sge_dif_page sge_dif_page;
+
+	/* Must be last --ends in a flexible-array member. */
+	struct hisi_sas_slot_buf_table slot_buf;
 };
 
 extern struct scsi_transport_template *hisi_sas_stt;
-- 
2.43.0

Re: [PATCH][next] scsi: hisi_sas: Avoid a couple -Wflex-array-member-not-at-end warnings

Posted by Gustavo A. R. Silva 2 months, 1 week ago

Hi all,

Friendly ping: who can take this, please?

Thanks!
-Gustavo

On 9/19/25 13:17, 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.
> 
> Move the conflicting declarations to the end of the corresponding
> structures (and in a union). Notice that `struct ssp_command_iu`
> is a flexible structure, this is a structure that contains a
> flexible-array member.
> 
> With these changes fix the following warnings:
> 
> drivers/scsi/hisi_sas/hisi_sas.h:639:38: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]
> drivers/scsi/hisi_sas/hisi_sas.h:616:47: 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 <gustavoars@kernel.org>
> ---
>   drivers/scsi/hisi_sas/hisi_sas.h | 10 +++++++---
>   1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/scsi/hisi_sas/hisi_sas.h b/drivers/scsi/hisi_sas/hisi_sas.h
> index 1323ed8aa717..55c638dd58b1 100644
> --- a/drivers/scsi/hisi_sas/hisi_sas.h
> +++ b/drivers/scsi/hisi_sas/hisi_sas.h
> @@ -613,8 +613,8 @@ struct hisi_sas_command_table_ssp {
>   	struct ssp_frame_hdr hdr;
>   	union {
>   		struct {
> -			struct ssp_command_iu task;
>   			u32 prot[PROT_BUF_SIZE];
> +			struct ssp_command_iu task;
>   		};
>   		struct ssp_tmf_iu ssp_task;
>   		struct xfer_rdy_iu xfer_rdy;
> @@ -636,13 +636,17 @@ struct hisi_sas_status_buffer {
>   
>   struct hisi_sas_slot_buf_table {
>   	struct hisi_sas_status_buffer status_buffer;
> -	union hisi_sas_command_table command_header;
>   	struct hisi_sas_sge_page sge_page;
> +
> +	/* Must be last --ends in a flexible-array member. */
> +	union hisi_sas_command_table command_header;
>   };
>   
>   struct hisi_sas_slot_dif_buf_table {
> -	struct hisi_sas_slot_buf_table slot_buf;
>   	struct hisi_sas_sge_dif_page sge_dif_page;
> +
> +	/* Must be last --ends in a flexible-array member. */
> +	struct hisi_sas_slot_buf_table slot_buf;
>   };
>   
>   extern struct scsi_transport_template *hisi_sas_stt;

Re: [PATCH][next] scsi: hisi_sas: Avoid a couple -Wflex-array-member-not-at-end warnings

Posted by Gustavo A. R. Silva 2 months, 1 week ago


On 10/7/25 11:45, Gustavo A. R. Silva wrote:
> Hi all,
> 
> Friendly ping: who can take this, please?
> 
> Thanks!
> -Gustavo
> 
> On 9/19/25 13:17, 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.
>>
>> Move the conflicting declarations to the end of the corresponding
>> structures (and in a union). Notice that `struct ssp_command_iu`
>> is a flexible structure, this is a structure that contains a
>> flexible-array member.
>>
>> With these changes fix the following warnings:
>>
>> drivers/scsi/hisi_sas/hisi_sas.h:639:38: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member- 
>> not-at-end]
>> drivers/scsi/hisi_sas/hisi_sas.h:616:47: 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 <gustavoars@kernel.org>
>> ---
>>   drivers/scsi/hisi_sas/hisi_sas.h | 10 +++++++---
>>   1 file changed, 7 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/scsi/hisi_sas/hisi_sas.h b/drivers/scsi/hisi_sas/hisi_sas.h
>> index 1323ed8aa717..55c638dd58b1 100644
>> --- a/drivers/scsi/hisi_sas/hisi_sas.h
>> +++ b/drivers/scsi/hisi_sas/hisi_sas.h
>> @@ -613,8 +613,8 @@ struct hisi_sas_command_table_ssp {
>>       struct ssp_frame_hdr hdr;
>>       union {
>>           struct {
>> -            struct ssp_command_iu task;
>>               u32 prot[PROT_BUF_SIZE];
>> +            struct ssp_command_iu task;
>>           };

Actually, I have a question here:

is u32 prot[PROT_BUF_SIZE]; intended to overlap flex array task.add_cdb[]
at some point?

if not, this change is just fine. Otherwise, I'd need to update this
patch to account for the overlap.

Could someone provide some feedback here? :)

Thanks!
-Gustavo

>>           struct ssp_tmf_iu ssp_task;
>>           struct xfer_rdy_iu xfer_rdy;
>> @@ -636,13 +636,17 @@ struct hisi_sas_status_buffer {
>>   struct hisi_sas_slot_buf_table {
>>       struct hisi_sas_status_buffer status_buffer;
>> -    union hisi_sas_command_table command_header;
>>       struct hisi_sas_sge_page sge_page;
>> +
>> +    /* Must be last --ends in a flexible-array member. */
>> +    union hisi_sas_command_table command_header;
>>   };
>>   struct hisi_sas_slot_dif_buf_table {
>> -    struct hisi_sas_slot_buf_table slot_buf;
>>       struct hisi_sas_sge_dif_page sge_dif_page;
>> +
>> +    /* Must be last --ends in a flexible-array member. */
>> +    struct hisi_sas_slot_buf_table slot_buf;
>>   };
>>   extern struct scsi_transport_template *hisi_sas_stt;
>