From: Kevin Traynor Date: Fri, 17 Apr 2020 15:43:35 +0000 (+0100) Subject: eal/x86: ignore gcc 10 stringop-overflow warnings X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=b5b3ea803e47;p=dpdk.git eal/x86: ignore gcc 10 stringop-overflow warnings stringop-overflow warns when it sees a possible overflow in a string operation. In the rte_memcpy functions different branches are taken depending on the size. stringop-overflow is raised for the branches in the function where it sees the static size of the src could be overflowed. However, in reality a correct size argument and in some cases dynamic allocation would ensure that this does not happen. For example, in the case below for key, the correct path will be chosen in rte_memcpy_generic at runtime based on the size argument but as some paths in the function could lead to a cast to 32 bytes a warning is raised. In function ‘_mm256_storeu_si256’, inlined from ‘rte_memcpy_generic’ at ../lib/librte_eal/common/include/arch/x86/rte_memcpy.h:315:2, inlined from ‘iavf_configure_rss_key’ at ../lib/librte_eal/common/include/arch/x86/rte_memcpy.h:869:10: /usr/lib/gcc/x86_64-redhat-linux/10/include/avxintrin.h:928:8: warning: writing 32 bytes into a region of size 1 [-Wstringop-overflow=] 928 | *__P = __A; | ~~~~~^~~~~ In file included from ../drivers/net/iavf/../../common/iavf/iavf_prototype.h:10, from ../drivers/net/iavf/iavf.h:9, from ../drivers/net/iavf/iavf_vchnl.c:22: ../drivers/net/iavf/iavf_vchnl.c: In function ‘iavf_configure_rss_key’: ../drivers/net/iavf/../../common/iavf/virtchnl.h:508:5: note: at offset 0 to object ‘key’ with size 1 declared here 508 | u8 key[1]; /* RSS hash key, packed bytes */ | ^~~ Ignore the stringop-overflow warnings for rte_memcpy.h functions. Bugzilla ID: 394 Bugzilla ID: 421 Cc: stable@dpdk.org Signed-off-by: Kevin Traynor Acked-by: Bruce Richardson Acked-by: Konstantin Ananyev --- diff --git a/lib/librte_eal/x86/include/rte_memcpy.h b/lib/librte_eal/x86/include/rte_memcpy.h index ba44c4a328..9c67232df9 100644 --- a/lib/librte_eal/x86/include/rte_memcpy.h +++ b/lib/librte_eal/x86/include/rte_memcpy.h @@ -22,6 +22,11 @@ extern "C" { #endif +#if defined(RTE_TOOLCHAIN_GCC) && (GCC_VERSION >= 100000) +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wstringop-overflow" +#endif + /** * Copy bytes from one location to another. The locations must not overlap. * @@ -869,6 +874,10 @@ rte_memcpy(void *dst, const void *src, size_t n) return rte_memcpy_generic(dst, src, n); } +#if defined(RTE_TOOLCHAIN_GCC) && (GCC_VERSION >= 100000) +#pragma GCC diagnostic pop +#endif + #ifdef __cplusplus } #endif