From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Qiu Subject: [PATCH v3] test-pmd: Fix pointer aliasing error Date: Thu, 4 Dec 2014 12:16:04 +0800 Message-ID: <1417666564-19950-1-git-send-email-michael.qiu@intel.com> References: <1417663711-19576-1-git-send-email-michael.qiu@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable To: dev-VfR2kkLFssw@public.gmane.org Return-path: In-Reply-To: <1417663711-19576-1-git-send-email-michael.qiu-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces-VfR2kkLFssw@public.gmane.org Sender: "dev" app/test-pmd/csumonly.c: In function =E2=80=98get_psd_sum=E2=80=99: build/include/rte_ip.h:161: error: dereferencing pointer =E2=80=98u16=E2=80= =99 does break strict-aliasing rules build/include/rte_ip.h:157: note: initialized from here ... The root cause is that, compile enable strict aliasing by default, while in function rte_raw_cksum() try to convert 'const char *' to 'const uint16_t *'. This patch is one workaround fix. Signed-off-by: Michael Qiu --- v3 --> v2: use uintptr_t instead of unsigned long to save pointer. v2 --> v1: Workaround solution instead of shut off the gcc params. lib/librte_net/rte_ip.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/lib/librte_net/rte_ip.h b/lib/librte_net/rte_ip.h index 61e4457..cda3436 100644 --- a/lib/librte_net/rte_ip.h +++ b/lib/librte_net/rte_ip.h @@ -154,7 +154,8 @@ struct ipv4_hdr { static inline uint16_t rte_raw_cksum(const char *buf, size_t len) { - const uint16_t *u16 =3D (const uint16_t *)buf; + uintptr_t ptr =3D (uintptr_t)buf; + const uint16_t *u16 =3D (const uint16_t *)ptr; uint32_t sum =3D 0; =20 while (len >=3D (sizeof(*u16) * 4)) { --=20 1.9.3