From patchwork Tue Jul 29 23:11:33 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andi Kleen X-Patchwork-Id: 4643641 Return-Path: X-Original-To: patchwork-linux-kbuild@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id AEAA2C0338 for ; Tue, 29 Jul 2014 23:12:46 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id EBE662012D for ; Tue, 29 Jul 2014 23:12:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E581A2014A for ; Tue, 29 Jul 2014 23:12:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754474AbaG2XMm (ORCPT ); Tue, 29 Jul 2014 19:12:42 -0400 Received: from mga02.intel.com ([134.134.136.20]:29589 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751889AbaG2XMk (ORCPT ); Tue, 29 Jul 2014 19:12:40 -0400 Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga101.jf.intel.com with ESMTP; 29 Jul 2014 16:12:39 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.01,760,1400050800"; d="scan'208";a="550957854" Received: from laut.jf.intel.com (HELO localhost) ([10.23.232.134]) by orsmga001.jf.intel.com with ESMTP; 29 Jul 2014 16:12:30 -0700 Received: by localhost (Postfix, from userid 1000) id 75B8B124AB5; Wed, 30 Jul 2014 01:11:41 +0200 (CEST) From: Andi Kleen To: mmarek@suse.cz Cc: linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, Andi Kleen Subject: [PATCH 2/2] Kbuild: Add a option to enable dwarf4 Date: Wed, 30 Jul 2014 01:11:33 +0200 Message-Id: <1406675493-2539-2-git-send-email-andi@firstfloor.org> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1406675493-2539-1-git-send-email-andi@firstfloor.org> References: <1406675493-2539-1-git-send-email-andi@firstfloor.org> Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org X-Spam-Status: No, score=-7.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Andi Kleen I found that a lot of unresolvable variables when using gdb on the kernel become resolvable when dwarf4 is enabled. So add a Kconfig flag to enable it. It definitely increases the debug information size, but on the other hand this isn't so bad when debug fusion is used. Signed-off-by: Andi Kleen --- Makefile | 3 +++ lib/Kconfig.debug | 9 +++++++++ 2 files changed, 12 insertions(+) diff --git a/Makefile b/Makefile index 6a717cd..6cdf3f0 100644 --- a/Makefile +++ b/Makefile @@ -696,6 +696,9 @@ KBUILD_CFLAGS += -g endif KBUILD_AFLAGS += -Wa,-gdwarf-2 endif +ifdef CONFIG_DEBUG_INFO_DWARF4 +KBUILD_CFLAGS += -gdwarf-4 +endif ifdef CONFIG_DEBUG_INFO_REDUCED KBUILD_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \ diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 0360468..a2dcf97 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -158,6 +158,15 @@ config DEBUG_INFO_SPLIT to know about the .dwo files and include them. Incompatible with older versions of ccache. +config DEBUG_INFO_DWARF4 + bool "Generate dwarf4 debuginfo" + depends on DEBUG_INFO + help + Generate dwarf4 debug info. This requires recent versions + of gcc and gdb. It makes the debug information larger. + But it significantly improves the success of resolving + variables in gdb on optimized code. + config ENABLE_WARN_DEPRECATED bool "Enable __deprecated logic" default y