| Message ID | 20180404094931.2345742-1-arnd@arndb.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Apr 4, 2018 at 11:49 AM, Arnd Bergmann <arnd@arndb.de> wrote: > A new set of warnings appeared in next-20180403 in some configurations > when gcc cannot see that rbd_assert(0) leads to an unreachable code > path: > > drivers/block/rbd.c: In function 'rbd_img_is_write': > drivers/block/rbd.c:1397:1: error: control reaches end of non-void function [-Werror=return-type] > drivers/block/rbd.c: In function '__rbd_obj_handle_request': > drivers/block/rbd.c:2499:1: error: control reaches end of non-void function [-Werror=return-type] > drivers/block/rbd.c: In function 'rbd_obj_handle_write': > drivers/block/rbd.c:2471:1: error: control reaches end of non-void function [-Werror=return-type] > > To work around this, we can add a return statement to each of these > cases. An alternative would be to remove the unlikely() annotation > in rbd_assert(), or to just use BUG()/BUG_ON() directly. This adds the > return statements, guessing what the most reasonable behavior > would be. Hi Arnd, I don't like these bogus return statements. Let's go with explicit BUG/BUG_ON() instead. Thanks, Ilya
On Wed, Apr 4, 2018 at 1:04 PM, Ilya Dryomov <idryomov@gmail.com> wrote: > On Wed, Apr 4, 2018 at 11:49 AM, Arnd Bergmann <arnd@arndb.de> wrote: >> A new set of warnings appeared in next-20180403 in some configurations >> when gcc cannot see that rbd_assert(0) leads to an unreachable code >> path: >> >> drivers/block/rbd.c: In function 'rbd_img_is_write': >> drivers/block/rbd.c:1397:1: error: control reaches end of non-void function [-Werror=return-type] >> drivers/block/rbd.c: In function '__rbd_obj_handle_request': >> drivers/block/rbd.c:2499:1: error: control reaches end of non-void function [-Werror=return-type] >> drivers/block/rbd.c: In function 'rbd_obj_handle_write': >> drivers/block/rbd.c:2471:1: error: control reaches end of non-void function [-Werror=return-type] >> >> To work around this, we can add a return statement to each of these >> cases. An alternative would be to remove the unlikely() annotation >> in rbd_assert(), or to just use BUG()/BUG_ON() directly. This adds the >> return statements, guessing what the most reasonable behavior >> would be. > > Hi Arnd, > > I don't like these bogus return statements. Let's go with explicit > BUG/BUG_ON() instead. Sounds good. Sent a v2 now. Arnd
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 07dc5419bd63..9445a71a9cd6 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -1394,6 +1394,7 @@ static bool rbd_img_is_write(struct rbd_img_request *img_req) default: rbd_assert(0); } + return false; } static void rbd_obj_handle_request(struct rbd_obj_request *obj_req); @@ -2468,6 +2469,7 @@ static bool rbd_obj_handle_write(struct rbd_obj_request *obj_req) default: rbd_assert(0); } + return true; } /* @@ -2496,6 +2498,7 @@ static bool __rbd_obj_handle_request(struct rbd_obj_request *obj_req) default: rbd_assert(0); } + return true; } static void rbd_obj_end_request(struct rbd_obj_request *obj_req)
A new set of warnings appeared in next-20180403 in some configurations when gcc cannot see that rbd_assert(0) leads to an unreachable code path: drivers/block/rbd.c: In function 'rbd_img_is_write': drivers/block/rbd.c:1397:1: error: control reaches end of non-void function [-Werror=return-type] drivers/block/rbd.c: In function '__rbd_obj_handle_request': drivers/block/rbd.c:2499:1: error: control reaches end of non-void function [-Werror=return-type] drivers/block/rbd.c: In function 'rbd_obj_handle_write': drivers/block/rbd.c:2471:1: error: control reaches end of non-void function [-Werror=return-type] To work around this, we can add a return statement to each of these cases. An alternative would be to remove the unlikely() annotation in rbd_assert(), or to just use BUG()/BUG_ON() directly. This adds the return statements, guessing what the most reasonable behavior would be. Fixes: 3da691bf4366 ("rbd: new request handling code") Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- drivers/block/rbd.c | 3 +++ 1 file changed, 3 insertions(+)