From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga01.intel.com ([192.55.52.88]:28837 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752501AbaG3Sve (ORCPT ); Wed, 30 Jul 2014 14:51:34 -0400 From: Andi Kleen Subject: [PATCH 2/2] Kbuild: Add a option to enable dwarf4 v2 Date: Wed, 30 Jul 2014 20:50:19 +0200 Message-Id: <1406746219-15427-2-git-send-email-andi@firstfloor.org> In-Reply-To: <1406746219-15427-1-git-send-email-andi@firstfloor.org> References: <1406746219-15427-1-git-send-email-andi@firstfloor.org> Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: mmarek@suse.cz Cc: linux-kbuild@vger.kernel.org, Andi Kleen 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. v2: Use cc-option Signed-off-by: Andi Kleen --- Makefile | 3 +++ lib/Kconfig.debug | 9 +++++++++ 2 files changed, 12 insertions(+) diff --git a/Makefile b/Makefile index 6a717cd..fd76983 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 += $(call cc-option, -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 -- 1.8.5.2