Some configurations produce this harmless warning when built with gcc -Wmaybe-uninitialized: infiniband/core/cma.c: In function 'cma_get_net_dev': infiniband/core/cma.c:1242:12: warning: 'src_addr_storage.sin_addr.s_addr' may be used uninitialized in this function [-Wmaybe-uninitialized] I previously reported this for the powerpc64 defconfig, but have now reproduced the same thing for x86 as well, using gcc-5 or higher. The code looks correct to me, and this change just rearranges it by making sure we alway initialize the entire address structure to make the warning disappear. My first approach added an initialization at the time of the declaration, which Doug commented may be too costly, so I hope this version doesn't add overhead. Link: http://arm-soc.lixom.net/buildlogs/mainline/v4.7-rc6/buildall.powerpc.ppc64_defconfig.log.passed Link: https://patchwork.kernel.org/patch/9212825/ Acked-by: Haggai Eran <haggaie at mellanox.com> Signed-off-by: Arnd Bergmann <arnd at arndb.de> --- This is marked v2 as the rest of the series but is actually version three of the patch as I had to do some other changes already. v3: remove accidental leftover change of the original patch drivers/infiniband/core/cma.c | 54 ++++++++++++++++++++++--------------------- 1 file changed, 28 insertions(+), 26 deletions(-) diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c index 36bf50e..89a6b05 100644 --- a/drivers/infiniband/core/cma.c +++ b/drivers/infiniband/core/cma.c @@ -1094,47 +1094,47 @@ static void cma_save_ib_info(struct sockaddr *src_addr, } } -static void cma_save_ip4_info(struct sockaddr *src_addr, - struct sockaddr *dst_addr, +static void cma_save_ip4_info(struct sockaddr_in *src_addr, + struct sockaddr_in *dst_addr, struct cma_hdr *hdr, __be16 local_port) { - struct sockaddr_in *ip4; - if (src_addr) { - ip4 = (struct sockaddr_in *)src_addr; - ip4->sin_family = AF_INET; - ip4->sin_addr.s_addr = hdr->dst_addr.ip4.addr; - ip4->sin_port = local_port; + *src_addr = (struct sockaddr_in) { + .sin_family = AF_INET, + .sin_addr.s_addr = hdr->dst_addr.ip4.addr, + .sin_port = local_port, + }; } if (dst_addr) { - ip4 = (struct sockaddr_in *)dst_addr; - ip4->sin_family = AF_INET; - ip4->sin_addr.s_addr = hdr->src_addr.ip4.addr; - ip4->sin_port = hdr->port; + *dst_addr = (struct sockaddr_in) { + .sin_family = AF_INET, + .sin_addr.s_addr = hdr->src_addr.ip4.addr, + .sin_port = hdr->port, + }; } } -static void cma_save_ip6_info(struct sockaddr *src_addr, - struct sockaddr *dst_addr, +static void cma_save_ip6_info(struct sockaddr_in6 *src_addr, + struct sockaddr_in6 *dst_addr, struct cma_hdr *hdr, __be16 local_port) { - struct sockaddr_in6 *ip6; - if (src_addr) { - ip6 = (struct sockaddr_in6 *)src_addr; - ip6->sin6_family = AF_INET6; - ip6->sin6_addr = hdr->dst_addr.ip6; - ip6->sin6_port = local_port; + *src_addr = (struct sockaddr_in6) { + .sin6_family = AF_INET6, + .sin6_addr = hdr->dst_addr.ip6, + .sin6_port = local_port, + }; } if (dst_addr) { - ip6 = (struct sockaddr_in6 *)dst_addr; - ip6->sin6_family = AF_INET6; - ip6->sin6_addr = hdr->src_addr.ip6; - ip6->sin6_port = hdr->port; + *dst_addr = (struct sockaddr_in6) { + .sin6_family = AF_INET6, + .sin6_addr = hdr->src_addr.ip6, + .sin6_port = hdr->port, + }; } } @@ -1159,10 +1159,12 @@ static int cma_save_ip_info(struct sockaddr *src_addr, switch (cma_get_ip_ver(hdr)) { case 4: - cma_save_ip4_info(src_addr, dst_addr, hdr, port); + cma_save_ip4_info((struct sockaddr_in *)src_addr, + (struct sockaddr_in *)dst_addr, hdr, port); break; case 6: - cma_save_ip6_info(src_addr, dst_addr, hdr, port); + cma_save_ip6_info((struct sockaddr_in6 *)src_addr, + (struct sockaddr_in6 *)dst_addr, hdr, port); break; default: return -EAFNOSUPPORT; -- 2.9.0
