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=-20.6 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable 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 C34EBC433E5 for ; Mon, 20 Jul 2020 06:17:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9D5802065F for ; Mon, 20 Jul 2020 06:17:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="jCza9kOb" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726076AbgGTGRq (ORCPT ); Mon, 20 Jul 2020 02:17:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36176 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725805AbgGTGRp (ORCPT ); Mon, 20 Jul 2020 02:17:45 -0400 Received: from mail-pl1-x64a.google.com (mail-pl1-x64a.google.com [IPv6:2607:f8b0:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7F5ABC0619D2 for ; Sun, 19 Jul 2020 23:17:45 -0700 (PDT) Received: by mail-pl1-x64a.google.com with SMTP id k4so9804466pll.6 for ; Sun, 19 Jul 2020 23:17:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=hrTZ3ILM0xAvfuFOaXWaqEFvmBYS4j5nhBs2MogC2d4=; b=jCza9kObWWd7hRrzAmTOlTIznNK5au/+obW9N2t3FEDENVbFaIuGNwvI+czZfkkjfj yz5Acv84a48iP3jdHNxPq9oYAQ3JsaCd43nn72tDwiAb0KzKjz0D1eRaxZPmSvNI3v5p 14yBIbxUS2mz1cy/VgcYLfGAwLfyPgaeo6KCWa24lFD8fcp2A8oN/a5lernNHq87QTsg uJDXeoEKZy1wotyY285VjM6pvyZt7ZdO0ouJqrQBQpT/blmMz44W6ZUa2RD3iVc6yJ3b 7Xl+rFZB34WWL6EpieqghLEjm+gNI2iCaVcFn7br2mXNH9ssLJR3SbfkLhib6q4xprWM isOg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=hrTZ3ILM0xAvfuFOaXWaqEFvmBYS4j5nhBs2MogC2d4=; b=WhBqVFD9NzAe0jNh6bYoXzkOvEDukDDtYnDlhPbiO740ILcbEgnjZAHfEJTx5JZv7u vtflUIR9cdGf3r5CzwAsSih2q3Cn60If1ntgLwBcSMr5EagZjidYVJ2iBSqEbDNSMMG8 c26lH5ICLZ8oyYzVXJGRCWoqv+3MXfm3+vUxjTmpLmqgmsYHoiKb92mk1Lt1cDfmQ9tR 00JQv+WngCykusi50slhQqz16fnU6/jzIf264syZGsI+OgYNrRjrgMjSGnD3wsqtjMkk tHmo9eh74EzkKBjmZPPvzojOIbfHi5/NcZuQMjUztOA6ua0cjeswu7BSPPBx+Mp8Bgze yPbg== X-Gm-Message-State: AOAM531xrxzRle3uOLKgBqA9Lk1dLXSEtiTjmAHvsD7GFj9VRwVxRF80 dhMHLMIoErjbFyqXCF3sMt3sNdAkYVO3 X-Google-Smtp-Source: ABdhPJxZ8KghvpQ17ZJUvd8FHOaqBfl50iarL4t96zD8AY8mjE1sgffczbDNvDrTORIDxuIPH0nKQjc6wtWJ X-Received: by 2002:a17:902:b78b:: with SMTP id e11mr16332011pls.204.1595225864907; Sun, 19 Jul 2020 23:17:44 -0700 (PDT) Date: Sun, 19 Jul 2020 23:17:41 -0700 Message-Id: <20200720061741.1514673-1-irogers@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.28.0.rc0.105.gf9edc3c819-goog Subject: [PATCH v2] libbpf bpf_helpers: Use __builtin_offsetof for offsetof From: Ian Rogers To: Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau , Song Liu , Yonghong Song , Andrii Nakryiko , John Fastabend , KP Singh , netdev@vger.kernel.org, bpf@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Stanislav Fomichev , Ian Rogers 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 The non-builtin route for offsetof has a dependency on size_t from stdlib.h/stdint.h that is undeclared and may break targets. The offsetof macro in bpf_helpers may disable the same macro in other headers that have a #ifdef offsetof guard. Rather than add additional dependencies improve the offsetof macro declared here to use the builtin that is available since llvm 3.7 (the first with a BPF backend). Signed-off-by: Ian Rogers --- tools/lib/bpf/bpf_helpers.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/lib/bpf/bpf_helpers.h b/tools/lib/bpf/bpf_helpers.h index a510d8ed716f..bc14db706b88 100644 --- a/tools/lib/bpf/bpf_helpers.h +++ b/tools/lib/bpf/bpf_helpers.h @@ -40,7 +40,7 @@ * Helper macro to manipulate data structures */ #ifndef offsetof -#define offsetof(TYPE, MEMBER) ((size_t)&((TYPE *)0)->MEMBER) +#define offsetof(TYPE, MEMBER) __builtin_offsetof(TYPE, MEMBER) #endif #ifndef container_of #define container_of(ptr, type, member) \ -- 2.28.0.rc0.105.gf9edc3c819-goog