On 3/4/19 7:49 PM, Marcel Apfelbaum wrote:
> Configuring QEMU with:
> ../configure --cc=clang --enable-rdma
>
> Leads to compilation error:
>
> CC migration/rdma.o
> CC migration/block.o
> qemu/migration/rdma.c:3615:58: error: taking address of packed member
> 'rkey' of class or structure
> 'RDMARegisterResult' may result in an unaligned pointer value
> [-Werror,-Waddress-of-packed-member]
> (uintptr_t)host_addr, NULL, ®_result->rkey,
> ^~~~~~~~~~~~~~~~
> Fix it by using a temp local variable.
>
> Signed-off-by: Marcel Apfelbaum <marcel.apfelb...@gmail.com>
> ---
>
> v1 -> v2:
> - Use a temp local variable (Dave)
Way cleaner than your v1 :)
>
> migration/rdma.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/migration/rdma.c b/migration/rdma.c
> index 54a3c11540..e39ee77558 100644
> --- a/migration/rdma.c
> +++ b/migration/rdma.c
> @@ -3611,13 +3611,16 @@ static int qemu_rdma_registration_handle(QEMUFile *f,
> void *opaque)
> }
> chunk_start = ram_chunk_start(block, chunk);
> chunk_end = ram_chunk_end(block, chunk + reg->chunks);
> + /* avoid "-Waddress-of-packed-member" warning */
No sure the comment is helpful.
> + uint32_t tmp_rkey = 0;
Probably no need to zero-initialize.
Anyway:
Reviewed-by: Philippe Mathieu-Daudé <phi...@redhat.com>
> if (qemu_rdma_register_and_get_keys(rdma, block,
> - (uintptr_t)host_addr, NULL, ®_result->rkey,
> + (uintptr_t)host_addr, NULL, &tmp_rkey,
> chunk, chunk_start, chunk_end)) {
> error_report("cannot get rkey");
> ret = -EINVAL;
> goto out;
> }
> + reg_result->rkey = tmp_rkey;
>
> reg_result->host_addr = (uintptr_t)block->local_host_addr;
>
>
