From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.warmcat.com (mail.warmcat.com [163.172.24.82]) by dpdk.org (Postfix) with ESMTP id B903CAAD7 for ; Mon, 21 May 2018 04:01:13 +0200 (CEST) From: Andy Green To: dev@dpdk.org Cc: thomas@monjalon.net Date: Mon, 21 May 2018 10:01:08 +0800 Message-ID: <152686806834.58694.15827888464125197583.stgit@localhost.localdomain> In-Reply-To: <152686781484.58694.14737673447518527445.stgit@localhost.localdomain> References: <152686781484.58694.14737673447518527445.stgit@localhost.localdomain> User-Agent: StGit/unknown-version Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Subject: [dpdk-dev] [PATCH v6 3/8] rte_ip.h: cast type decided by sizeof to uint32 X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 21 May 2018 02:01:14 -0000 /projects/lagopus/src/dpdk/build/include/rte_ip.h: In function 'rte_ipv4_udptcp_cksum': /projects/lagopus/src/dpdk/build/include/rte_byteorder.h: 51:24: warning: conversion from 'long unsigned int' to 'uint32_t' {aka 'unsigned int'} may change value [-Wconversion] #define rte_bswap16(x) ((uint16_t) (__builtin_constant_p(x) ? \ ^ /projects/lagopus/src/dpdk/build/include/rte_byteorder.h: 85:29: note: in expansion of macro 'rte_bswap16' #define rte_be_to_cpu_16(x) rte_bswap16(x) ^~~~~~~~~~~ /projects/lagopus/src/dpdk/build/include/rte_ip.h:321:11: note: in expansion of macro 'rte_be_to_cpu_16' l4_len = rte_be_to_cpu_16(ipv4_hdr->total_length) - ^~~~~~~~~~~~~~~~ Also with this one, it is a cast that always occurred and is just being done explicitly, with no changes to the generated code. The warning stack is misleading, it points to the last element in the macro that produced the lhs of the subtraction above. But the only "unsigned long int" in the expression is the result of the sizeof() on the rhs, it promotes the subtraction result to unsigned long. So the error actually relates to the result of the outer subtraction. The actual error is "you are trying to put an unsigned long into a uint32_t". We always did so, the fix is just to inform the compiler it is intentional with an explicit cast. Fixes: 6006818cfb ("net: new checksum functions") Signed-off-by: Andy Green --- lib/librte_net/rte_ip.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/lib/librte_net/rte_ip.h b/lib/librte_net/rte_ip.h index c924aca7f..72dc2456a 100644 --- a/lib/librte_net/rte_ip.h +++ b/lib/librte_net/rte_ip.h @@ -318,8 +318,8 @@ rte_ipv4_udptcp_cksum(const struct ipv4_hdr *ipv4_hdr, const void *l4_hdr) uint32_t cksum; uint32_t l4_len; - l4_len = rte_be_to_cpu_16(ipv4_hdr->total_length) - - sizeof(struct ipv4_hdr); + l4_len = (uint32_t)(rte_be_to_cpu_16(ipv4_hdr->total_length) - + sizeof(struct ipv4_hdr)); cksum = rte_raw_cksum(l4_hdr, l4_len); cksum += rte_ipv4_phdr_cksum(ipv4_hdr, 0);