From b74e21ab7d438117a10d2d331bdfc275fcab2970 Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Thu, 28 Feb 2019 22:19:41 -0800 Subject: samples/bpf: silence compiler warning for xdpsock_user.c MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Compiling xdpsock_user.c with 4.8.5, I hit the following compilation warning: HOSTCC samples/bpf/xdpsock_user.o /data/users/yhs/work/net-next/samples/bpf/xdpsock_user.c: In function ‘main’: /data/users/yhs/work/net-next/samples/bpf/xdpsock_user.c:449:6: warning: ‘idx_cq’ may be used unini tialized in this function [-Wmaybe-uninitialized] u32 idx_cq, idx_fq; ^ /data/users/yhs/work/net-next/samples/bpf/xdpsock_user.c:606:7: warning: ‘idx_rx’ may be used unini tialized in this function [-Wmaybe-uninitialized] u32 idx_rx, idx_tx = 0; ^ /data/users/yhs/work/net-next/samples/bpf/xdpsock_user.c:506:6: warning: ‘idx_rx’ may be used unini tialized in this function [-Wmaybe-uninitialized] u32 idx_rx, idx_fq = 0; As an example, the code pattern looks like: u32 idx_cq; ... ret = xsk_ring_prod__reserve(&xsk->umem->fq, rcvd, &idx_fq); if (ret) { ... } ... idx_fq ... The compiler warns since it does not know whether &idx_fq is assigned or not inside the library function xsk_ring_prod__reserve(). Let us assign an initial value 0 to such auto variables to silence compiler warning. Fixes: 248c7f9c0e21 ("samples/bpf: convert xdpsock to use libbpf for AF_XDP access") Signed-off-by: Yonghong Song Acked-by: Jonathan Lemon Acked-by: Song Liu Signed-off-by: Daniel Borkmann --- samples/bpf/xdpsock_user.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'samples') diff --git a/samples/bpf/xdpsock_user.c b/samples/bpf/xdpsock_user.c index 9c76d6d43deb..d08ee1ab7bb4 100644 --- a/samples/bpf/xdpsock_user.c +++ b/samples/bpf/xdpsock_user.c @@ -446,7 +446,7 @@ static void kick_tx(struct xsk_socket_info *xsk) static inline void complete_tx_l2fwd(struct xsk_socket_info *xsk) { - u32 idx_cq, idx_fq; + u32 idx_cq = 0, idx_fq = 0; unsigned int rcvd; size_t ndescs; @@ -503,7 +503,7 @@ static inline void complete_tx_only(struct xsk_socket_info *xsk) static void rx_drop(struct xsk_socket_info *xsk) { unsigned int rcvd, i; - u32 idx_rx, idx_fq = 0; + u32 idx_rx = 0, idx_fq = 0; int ret; rcvd = xsk_ring_cons__peek(&xsk->rx, BATCH_SIZE, &idx_rx); @@ -603,7 +603,7 @@ static void l2fwd(struct xsk_socket_info *xsk) { for (;;) { unsigned int rcvd, i; - u32 idx_rx, idx_tx = 0; + u32 idx_rx = 0, idx_tx = 0; int ret; for (;;) { -- cgit v1.2.3-59-g8ed1b