[PATCH RFC 3/3] libvduse: Fix assignment in vring_set_avail_event

[Marcel Holtmann]

  CC       libvduse.o
libvduse.c: In function ‘vring_set_avail_event’:
libvduse.c:603:7: error: dereferencing type-punned pointer will break 
strict-aliasing rules [-Werror=strict-aliasin]
  603 |     *((uint16_t *)&vq->vring.used->ring[vq->vring.num]) = htole16(val);
      |      ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
---
 subprojects/libvduse/libvduse.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/subprojects/libvduse/libvduse.c b/subprojects/libvduse/libvduse.c
index 338ad5e352e7..51a4ba1b6878 100644
--- a/subprojects/libvduse/libvduse.c
+++ b/subprojects/libvduse/libvduse.c
@@ -582,7 +582,10 @@ void vduse_queue_notify(VduseVirtq *vq)
 
 static inline void vring_set_avail_event(VduseVirtq *vq, uint16_t val)
 {
-    *((uint16_t *)&vq->vring.used->ring[vq->vring.num]) = htole16(val);
+    vring_used_elem_t *ring = &vq->vring.used->ring[vq->vring.num];
+
+    /* FIXME: Is this actually correct since this is __virtio32 id; */
+    ring->id = htole16(val);
 }
 
 static bool vduse_queue_map_single_desc(VduseVirtq *vq, unsigned int *p_num_sg,
-- 
2.38.1