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 C49DF231E for ; Tue, 22 May 2018 03:24:28 +0200 (CEST) From: Andy Green To: dev@dpdk.org Cc: thomas@monjalon.net Date: Tue, 22 May 2018 09:24:17 +0800 Message-ID: <152695225724.111551.14547336137229234122.stgit@localhost.localdomain> In-Reply-To: <152695215195.111551.10652921922687464367.stgit@localhost.localdomain> References: <152695215195.111551.10652921922687464367.stgit@localhost.localdomain> User-Agent: StGit/unknown-version Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Subject: [dpdk-dev] [PATCH v7 2/8] rte_rwlock.h: gcc8 sign conversion warnings 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: Tue, 22 May 2018 01:24:29 -0000 In file included from /projects/lagopus/src/dpdk/ build/include/rte_rwlock.h:12, from ./mgr/lock.h:24, from ./mgr/sock_io.c:54: /projects/lagopus/src/dpdk/build/include/generic/ rte_rwlock.h: In function 'rte_rwlock_read_lock': /projects/lagopus/src/dpdk/build/include/generic/ rte_rwlock.h:74:12: warning: conversion to 'uint32_t' {aka 'unsigned int'} from 'int32_t' {aka 'int'} may change the sign of the result [-Wsign-conversion] x, x + 1); ^ /projects/lagopus/src/dpdk/build/include/generic/ rte_rwlock.h:74:17: warning: conversion to 'uint32_t' {aka 'unsigned int'} from 'int' may change the sign of the result [-Wsign-conversion] x, x + 1); ~~^~~ /projects/lagopus/src/dpdk/build/include/generic/ rte_rwlock.h: In function 'rte_rwlock_write_lock': /projects/lagopus/src/dpdk/build/include/generic/ rte_rwlock.h:110:15: warning: unsigned conversion from 'int' to 'uint32_t' {aka 'unsigned int'} changes value from '-1' to '4294967295' [-Wsign-conversion] 0, -1); ^~ Again in this case we are making explicit the exact cast that was always happening implicitly. The patch does not change the generated code. The int32_t temp "x" is required to be signed to detect a < 0 error condition from the lock status. Afterwards, it has always been implicitly cast to uint32_t when it is used in the arguments to rte_atomic32_cmpset()... gcc8.1 objects to the implicit cast now and requires us to cast it explicitly. Fixes: af75078fec ("first public release") Signed-off-by: Andy Green Acked-by: Bruce Richardson --- lib/librte_eal/common/include/generic/rte_rwlock.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/lib/librte_eal/common/include/generic/rte_rwlock.h b/lib/librte_eal/common/include/generic/rte_rwlock.h index 899e9bc43..5751a0e6d 100644 --- a/lib/librte_eal/common/include/generic/rte_rwlock.h +++ b/lib/librte_eal/common/include/generic/rte_rwlock.h @@ -71,7 +71,7 @@ rte_rwlock_read_lock(rte_rwlock_t *rwl) continue; } success = rte_atomic32_cmpset((volatile uint32_t *)&rwl->cnt, - x, x + 1); + (uint32_t)x, (uint32_t)(x + 1)); } } @@ -107,7 +107,7 @@ rte_rwlock_write_lock(rte_rwlock_t *rwl) continue; } success = rte_atomic32_cmpset((volatile uint32_t *)&rwl->cnt, - 0, -1); + 0, (uint32_t)-1); } }