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=-17.4 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 101F2C433E0 for ; Fri, 12 Feb 2021 16:04:59 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B51D664E6B for ; Fri, 12 Feb 2021 16:04:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B51D664E6B Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.84358.158194 (Exim 4.92) (envelope-from ) id 1lAaw0-0004hC-Cs; Fri, 12 Feb 2021 16:04:44 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 84358.158194; Fri, 12 Feb 2021 16:04:44 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lAaw0-0004h5-9d; Fri, 12 Feb 2021 16:04:44 +0000 Received: by outflank-mailman (input) for mailman id 84358; Fri, 12 Feb 2021 16:04:43 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lAavz-0004h0-4p for xen-devel@lists.xenproject.org; Fri, 12 Feb 2021 16:04:43 +0000 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 5e3c1277-d2ac-4405-95cc-f2f6a5f1036c; Fri, 12 Feb 2021 16:04:42 +0000 (UTC) Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 8D2A2AD29; Fri, 12 Feb 2021 16:04:41 +0000 (UTC) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 5e3c1277-d2ac-4405-95cc-f2f6a5f1036c X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1613145881; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Hw8Go3FxPM3rNPpPAh6+TMrhXG8uCHjrpH86/xDkyKo=; b=JV+UoQqKlwJPUV7J1JLrbdXE7epIdvgACTfTToq8IsaGCnNnWTQjsQZGQQuQJj1GiXeUjP hmUFjQihqDME5XkpOSjOVeT3//VDt1GCwXdnmfFUrjmSucI2tgRJeqUMF+ZbCneEzaLMIx gQ6PIeEF0W0TeCRpJooK8hahO12eENA= Subject: Re: [PATCH 07/10] tools: Use -Og for debug builds when available To: Andrew Cooper Cc: Ian Jackson , Wei Liu , Juergen Gross , Xen-devel References: <20210212153953.4582-1-andrew.cooper3@citrix.com> <20210212153953.4582-8-andrew.cooper3@citrix.com> From: Jan Beulich Message-ID: <04c93a14-ee95-e4a6-33b9-f80fcd03a010@suse.com> Date: Fri, 12 Feb 2021 17:04:42 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <20210212153953.4582-8-andrew.cooper3@citrix.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit On 12.02.2021 16:39, Andrew Cooper wrote: > The recommended optimisation level for debugging is -Og, and is what tools > such as gdb prefer. In practice, it equates to -01 with a few specific > optimisations turned off. > > abi-dumper in particular wants the libraries it inspects in this form. > > Signed-off-by: Andrew Cooper Reviewed-by: Jan Beulich > --- a/tools/Rules.mk > +++ b/tools/Rules.mk > @@ -106,8 +106,9 @@ endif > CFLAGS_libxenlight += $(CFLAGS_libxenctrl) > > ifeq ($(debug),y) > -# Disable optimizations > -CFLAGS += -O0 -fno-omit-frame-pointer > +# Use -Og if available, -O0 otherwise > +dbg_opt_level := $(call cc-option,$(CC),-Og,-O0) > +CFLAGS += $(dbg_opt_level) -fno-omit-frame-pointer I wonder if we shouldn't do something similar for the hypervisor, where we use -O1 for debug builds right now. At least when DEBUG_INFO is also enabled, -Og may be better. Jan