From 52f758edc9f9f0b1f4f83eb668a5f76482ce00ca Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Fri, 12 Dec 2025 15:44:50 +0900 Subject: [PATCH] hyperv: Avoid -Wflex-array-member-not-at-end warning -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 warning: include/hyperv/hvgdk_mini.h:581:25: 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. This overlays the trailing MEMBER u64 gva_list[]; onto the FAM struct hv_tlb_flush_ex::hv_vp_set.bank_contents[], while keeping the FAM and the start of MEMBER aligned. The static_assert() ensures this alignment remains, and it's intentionally placed inmediately after the related structure --no blank line in between. Signed-off-by: Gustavo A. R. Silva Signed-off-by: Wei Liu --- include/hyperv/hvgdk_mini.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/include/hyperv/hvgdk_mini.h b/include/hyperv/hvgdk_mini.h index 04b18d0e37af3..30fbbde81c5c4 100644 --- a/include/hyperv/hvgdk_mini.h +++ b/include/hyperv/hvgdk_mini.h @@ -578,9 +578,12 @@ struct hv_tlb_flush { /* HV_INPUT_FLUSH_VIRTUAL_ADDRESS_LIST */ struct hv_tlb_flush_ex { u64 address_space; u64 flags; - struct hv_vpset hv_vp_set; - u64 gva_list[]; + __TRAILING_OVERLAP(struct hv_vpset, hv_vp_set, bank_contents, __packed, + u64 gva_list[]; + ); } __packed; +static_assert(offsetof(struct hv_tlb_flush_ex, hv_vp_set.bank_contents) == + offsetof(struct hv_tlb_flush_ex, gva_list)); struct ms_hyperv_tsc_page { /* HV_REFERENCE_TSC_PAGE */ volatile u32 tsc_sequence; -- 2.47.3