rbd: work around -Wuninitialized warning

[ Upstream commit a55e601b2f02df5db7070e9a37bd655c9c576a52 ]

gcc -O3 warns about a dummy variable that is passed
down into rbd_img_fill_nodata without being initialized:

drivers/block/rbd.c: In function 'rbd_img_fill_nodata':
drivers/block/rbd.c:2573:13: error: 'dummy' is used uninitialized in this function [-Werror=uninitialized]
  fctx->iter = *fctx->pos;

Since this is a dummy, I assume the warning is harmless, but
it's better to initialize it anyway and avoid the warning.

Fixes: mmtom ("init/Kconfig: enable -O3 for all arches")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 13527a0..a673157 100644 (file)
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -2739,7 +2739,7 @@ static int rbd_img_fill_nodata(struct rbd_img_request *img_req,
                               u64 off, u64 len)
 {
        struct ceph_file_extent ex = { off, len };
-       union rbd_img_fill_iter dummy;
+       union rbd_img_fill_iter dummy = {};
        struct rbd_img_fill_ctx fctx = {
                .pos_type = OBJ_REQUEST_NODATA,
                .pos = &dummy,