From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 777F7C43381 for ; Thu, 21 Mar 2019 18:23:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5408221874 for ; Thu, 21 Mar 2019 18:23:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728705AbfCUSXF (ORCPT ); Thu, 21 Mar 2019 14:23:05 -0400 Received: from mail-qt1-f194.google.com ([209.85.160.194]:35273 "EHLO mail-qt1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727829AbfCUSXF (ORCPT ); Thu, 21 Mar 2019 14:23:05 -0400 Received: by mail-qt1-f194.google.com with SMTP id h39so7755512qte.2; Thu, 21 Mar 2019 11:23:04 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=0QmXAKtZ9yVDHBruxl6smjOl/FBnQRtl/rZ8vXH7wuE=; b=Wd4YQnu2kAU/F2SNwa6uFwZSCHCAYwrVfDXqAzUFZWM837h0JRkikrscbH4FgrpK9+ u3TK45X6uLXLn2WZsk1ocWE6jana9XotdAIJHr58nJZk+mbCdVk4IjUf0vaPncKMuLtU oMgjEZmUPwZZLje3F8J7aogxtNAPsSyMNhVWOH08z9f/VhdHK8iO+248kqeh2B5mrk0E aLc6u7SJzE9v3CJ3j+4RUbhlMTuCwd3WlvyfrriBpkdw0ytwf34rjLRFddSNd6AekrgU oi5jZgtm3oxC7QvcVwDXIMmoKNxz90qwc6P3l6Bpbg6/4nJKoBesznjZCwlYZ8y/JtE+ /SrQ== X-Gm-Message-State: APjAAAVmptvdBNzZkwdYjmS9kl0IyJedV4Jqm0nIcwpOlDARQdvugeg9 E5Qx3b1SyX3UIb/zt0UoSWfJurY3pOXARA1M+zE= X-Google-Smtp-Source: APXvYqyQ+XpjLp6lEdRkcL177XeFciCcGl7M7jMvTYvYq78ppAnqKCigF+TzBdku4JtAkqefY1m2eME0WF4F+5JsK8k= X-Received: by 2002:ac8:3fbc:: with SMTP id d57mr4133770qtk.96.1553192583731; Thu, 21 Mar 2019 11:23:03 -0700 (PDT) MIME-Version: 1.0 References: <20190308001723.GA11197@archlinux-ryzen> <20190320190752.GA28744@archlinux-ryzen> In-Reply-To: From: Arnd Bergmann Date: Thu, 21 Mar 2019 19:22:46 +0100 Message-ID: Subject: Re: -Wsometimes-uninitialized Clang warning in net/tipc/node.c To: Jon Maloy Cc: Nick Desaulniers , Nathan Chancellor , Ying Xue , "David S. Miller" , "tipc-discussion@lists.sourceforge.net" , Networking , LKML , "clang-built-linux@googlegroups.com" Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Mar 21, 2019 at 4:25 PM Arnd Bergmann wrote: > > On Thu, Mar 21, 2019 at 3:57 PM Jon Maloy wrote: > > > > > > diff --git a/net/tipc/node.c b/net/tipc/node.c index > > > 2dc4919ab23c..147786795e48 100644 > > > --- a/net/tipc/node.c > > > +++ b/net/tipc/node.c > > > @@ -844,7 +844,8 @@ static void tipc_node_link_down(struct tipc_node *n, > > > int bearer_id, bool delete) > > > tipc_node_write_unlock(n); > > > if (delete) > > > tipc_mon_remove_peer(n->net, n->addr, old_bearer_id); > > > - tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr); > > > + if (skb_queue_empty(xmitq)) > > > + tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr); > > > tipc_sk_rcv(n->net, &le->inputq); } > > > > > > This duplicates the check inside of skb_queue_empty(), but I don't know if > > > the compiler can see through the logic behind the inlined function calls. > > > > Probably not, but this is not in any way time critical. > > I meant it's unclear whether compilers should be expected to see that > skb_queue_empty() is true after the call to __skb_queue_head_init() > initializes it. I reproduced the warning now, and verified that my change eliminates the warning. I still think that is the more logical solution here. Arnd