gcc 10.0.1 reports: error: array subscript 0 is outside the bounds of an
interior zero-length array 'RTE_MARKER64' {aka 'long unsigned int[0]'}
[-Werror=zero-length-bounds] 310 | *(uint64_t *)(&mbuf->rearm_data) =
val;
Declaring zero-length arrays in other contexts, including as interior
members of structure objects or as non-member objects, is discouraged.
Accessing elements of zero-length arrays declared in such contexts is
undefined and may be diagnosed.[1]
Fix by using unnamed union and struct.
https://bugs.dpdk.org/show_bug.cgi?id=396
Bugzilla ID: 396
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
Fixes: 3e6181b07038 ("mbuf: use structure marker from EAL")
Cc: sta...@dpdk.org
Signed-off-by: Gavin Hu <gavin...@arm.com>
---
lib/librte_mbuf/rte_mbuf_core.h | 54 +++++++++++++++++++--------------
1 file changed, 32 insertions(+), 22 deletions(-)
diff --git a/lib/librte_mbuf/rte_mbuf_core.h b/lib/librte_mbuf/rte_mbuf_core.h
index b9a59c879..5390ddcfa 100644
--- a/lib/librte_mbuf/rte_mbuf_core.h
+++ b/lib/librte_mbuf/rte_mbuf_core.h
@@ -480,31 +480,41 @@ struct rte_mbuf {
rte_iova_t buf_physaddr; /**< deprecated */
} __rte_aligned(sizeof(rte_iova_t));
- /* next 8 bytes are initialised on RX descriptor rearm */
- RTE_MARKER64 rearm_data;
- uint16_t data_off;
-
- /**
- * Reference counter. Its size should at least equal to the size
- * of port field (16 bits), to support zero-copy broadcast.
- * It should only be accessed using the following functions:
- * rte_mbuf_refcnt_update(), rte_mbuf_refcnt_read(), and
- * rte_mbuf_refcnt_set(). The functionality of these functions (atomic,
- * or non-atomic) is controlled by the CONFIG_RTE_MBUF_REFCNT_ATOMIC
- * config option.
- */
RTE_STD_C11
union {
- rte_atomic16_t refcnt_atomic; /**< Atomically accessed refcnt */
- /** Non-atomically accessed refcnt */
- uint16_t refcnt;
- };
- uint16_t nb_segs; /**< Number of segments. */
+ /* next 8 bytes are initialised on RX descriptor rearm */
+ uint64_t rearm_data;
+ RTE_STD_C11
+ struct {
+ uint16_t data_off;
+
+ /**
+ * Reference counter. Its size should at least equal to
+ * the size of port field (16 bits), to support
+ * zero-copy broadcast. It should only be accessed
+ * using the following functions:
+ * rte_mbuf_refcnt_update(), rte_mbuf_refcnt_read(),
+ * and rte_mbuf_refcnt_set(). The functionality of
+ * these functions (atomic, or non-atomic) is
+ * controlled by the CONFIG_RTE_MBUF_REFCNT_ATOMIC
+ * config option.
+ */
+ RTE_STD_C11
+ union {
+ /**< Atomically accessed refcnt */
+ rte_atomic16_t refcnt_atomic;
+ /** Non-atomically accessed refcnt */
+ uint16_t refcnt;
+ };
+ uint16_t nb_segs; /**< Number of segments. */
- /** Input port (16 bits to support more than 256 virtual ports).
- * The event eth Tx adapter uses this field to specify the output port.
- */
- uint16_t port;
+ /** Input port (16 bits to support more than 256
+ * virtual ports). The event eth Tx adapter uses this
+ * field to specify the output port.
+ */
+ uint16_t port;
+ };
+ };
uint64_t ol_flags; /**< Offload features. */
--
2.25.0
