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 new TRAILING_OVERLAP() helper to fix a dozen instances of
> the following type of warning:
>
> drivers/acpi/nfit/intel.c:692:35: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]
>
> Acked-by: Dan Williams <dan.j.williams@xxxxxxxxx>
> Tested-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Looks like our mails crossed [1], but I rushed this testing, apologies.
This patch does cause a regression, and the conversion is not equivalent
according to pahole:
union pkg_nd_intel_bus_fw_activate {
struct nd_cmd_pkg pkg; /* 0 64 */
struct {
u8 _offset_to_fam[64]; /* 0 64 */
/* --- cacheline 1 boundary (64 bytes) --- */
struct nd_intel_bus_fw_activate cmd; /* 64 5 */
} __attribute__((__packed__)); /* 0 69 */
};
struct pkg_nd_intel_bus_fw_activate2 {
struct nd_cmd_pkg pkg; /* 0 64 */
/* XXX last struct has a flexible array */
/* --- cacheline 1 boundary (64 bytes) --- */
struct nd_intel_bus_fw_activate cmd; /* 64 5 */
/* size: 72, cachelines: 2, members: 2 */
/* padding: 3 */
/* flexible array members: end: 1 */
/* last cacheline: 8 bytes */
};
Now, why the padding at the end matters for this test, I am still
trying to figure that out.
[1]: http://lore.kernel.org/685c772aa7cc1_23a2a10080@dwillia2-mobl4.notmuch
