From patchwork Tue Jul 15 23:16:12 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andi Kleen X-Patchwork-Id: 4561971 Return-Path: X-Original-To: patchwork-linux-kbuild@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 351319F37C for ; Tue, 15 Jul 2014 23:18:00 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 7A3E72017E for ; Tue, 15 Jul 2014 23:17:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8BEA820123 for ; Tue, 15 Jul 2014 23:17:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758743AbaGOXRL (ORCPT ); Tue, 15 Jul 2014 19:17:11 -0400 Received: from mga09.intel.com ([134.134.136.24]:13406 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755932AbaGOXRI (ORCPT ); Tue, 15 Jul 2014 19:17:08 -0400 Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga102.jf.intel.com with ESMTP; 15 Jul 2014 16:11:32 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.01,668,1400050800"; d="scan'208";a="573734246" Received: from laut.jf.intel.com (HELO localhost) ([10.23.232.55]) by orsmga002.jf.intel.com with ESMTP; 15 Jul 2014 16:17:07 -0700 Received: by localhost (Postfix, from userid 1000) id 29BA5124A5F; Wed, 16 Jul 2014 01:16:19 +0200 (CEST) From: Andi Kleen To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Andi Kleen Subject: [PATCH 2/2] Kbuild: Add a option to enable dwarf4 Date: Wed, 16 Jul 2014 01:16:12 +0200 Message-Id: <1405466172-17055-2-git-send-email-andi@firstfloor.org> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1405466172-17055-1-git-send-email-andi@firstfloor.org> References: <1405466172-17055-1-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=-6.9 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 953659e..9c4080b 100644 --- a/Makefile +++ b/Makefile @@ -690,6 +690,9 @@ KBUILD_CFLAGS += -g KBUILD_AFLAGS += -Wa,-gdwarf-2 endif 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 fb07c33..1af4d96 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -156,6 +156,15 @@ 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