From: Gustavo A. R. Silva Date: Fri, 19 Sep 2025 11:56:29 +0000 (+0200) Subject: scsi: megaraid_sas: Avoid a couple -Wflex-array-member-not-at-end warnings X-Git-Tag: v6.19-rc1~95^2~50 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=81cb6c228ff877ca0046a432ea831788590633ff;p=thirdparty%2Fkernel%2Flinux.git scsi: megaraid_sas: Avoid a couple -Wflex-array-member-not-at-end warnings -Wflex-array-member-not-at-end was introduced in GCC-14, and we are getting ready to enable it, globally. Use the new TRAILING_OVERLAP() helper to fix the following warnings: drivers/scsi/megaraid/megaraid_sas_fusion.h:1153:31: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] drivers/scsi/megaraid/megaraid_sas_fusion.h:1198:32: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] This helper creates a union between a flexible-array member (FAM) and a set of MEMBERS that would otherwise follow it --in this case 'struct MR_LD_SPAN_MAP ldSpanMap[MAX_LOGICAL_DRIVES_DYN]' and 'struct MR_LD_SPAN_MAP ldSpanMap[MAX_LOGICAL_DRIVES]' in the corresponding structures. This overlays the trailing members onto the FAM (struct MR_LD_SPAN_MAP ldSpanMap[];) while keeping the FAM and the start of MEMBERS aligned. The static_assert() ensures this alignment remains, and it's intentionally placed inmediately after the corresponding structures --no blank line in between. Signed-off-by: Gustavo A. R. Silva Link: https://patch.msgid.link/aM1E7Xa8qYdZ598N@kspp Signed-off-by: Martin K. Petersen --- diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.h b/drivers/scsi/megaraid/megaraid_sas_fusion.h index b677d80e58747..ddeea0ee28344 100644 --- a/drivers/scsi/megaraid/megaraid_sas_fusion.h +++ b/drivers/scsi/megaraid/megaraid_sas_fusion.h @@ -1150,9 +1150,13 @@ typedef struct LOG_BLOCK_SPAN_INFO { } LD_SPAN_INFO, *PLD_SPAN_INFO; struct MR_FW_RAID_MAP_ALL { - struct MR_FW_RAID_MAP raidMap; - struct MR_LD_SPAN_MAP ldSpanMap[MAX_LOGICAL_DRIVES]; + /* Must be last --ends in a flexible-array member. */ + TRAILING_OVERLAP(struct MR_FW_RAID_MAP, raidMap, ldSpanMap, + struct MR_LD_SPAN_MAP ldSpanMap[MAX_LOGICAL_DRIVES]; + ); } __attribute__ ((packed)); +static_assert(offsetof(struct MR_FW_RAID_MAP_ALL, raidMap.ldSpanMap) == + offsetof(struct MR_FW_RAID_MAP_ALL, ldSpanMap)); struct MR_DRV_RAID_MAP { /* total size of this structure, including this field. @@ -1194,10 +1198,13 @@ struct MR_DRV_RAID_MAP { * And it is mainly for code re-use purpose. */ struct MR_DRV_RAID_MAP_ALL { - - struct MR_DRV_RAID_MAP raidMap; - struct MR_LD_SPAN_MAP ldSpanMap[MAX_LOGICAL_DRIVES_DYN]; + /* Must be last --ends in a flexible-array member. */ + TRAILING_OVERLAP(struct MR_DRV_RAID_MAP, raidMap, ldSpanMap, + struct MR_LD_SPAN_MAP ldSpanMap[MAX_LOGICAL_DRIVES_DYN]; + ); } __packed; +static_assert(offsetof(struct MR_DRV_RAID_MAP_ALL, raidMap.ldSpanMap) == + offsetof(struct MR_DRV_RAID_MAP_ALL, ldSpanMap));