From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: [PATCH] Move -fno-dwarf2-cfi-asm to powerpc only Date: Mon, 21 Dec 2009 02:23:51 +0100 Message-ID: <20091221012351.GA24720@basil.fritz.box> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from one.firstfloor.org ([213.235.205.2]:58872 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756229AbZLUBXx (ORCPT ); Sun, 20 Dec 2009 20:23:53 -0500 Content-Disposition: inline Sender: linux-arch-owner@vger.kernel.org List-ID: To: akpm@osdl.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, kyle@redhat.com, benh@kernel.crashing.org, mmarek@suse.cz Move -fno-dwarf2-cfi-asm to powerpc only Better dwarf2 unwind information is a good thing, it allows better debugging with kgdb and crash and helps systemtap. commit 003086497f07f7f1e67c0c295e261740f822b377 disabled some CFI information globally to work around a module loader bug on powerpc. But this disables the better unwind tables for all architectures, not just powerpc. Move the workaround to powerpc and also add a suitable comment that's it really a workaround. This improves dwarf2 unwind tables on x86 at least. Cc: kyle@redhat.com Cc: benh@kernel.crashing.org Cc: mmarek@suse.cz Signed-off-by: Andi Kleen --- Makefile | 3 --- arch/powerpc/Makefile | 5 +++++ 2 files changed, 5 insertions(+), 3 deletions(-) Index: linux-2.6.33-rc1-ak/Makefile =================================================================== --- linux-2.6.33-rc1-ak.orig/Makefile +++ linux-2.6.33-rc1-ak/Makefile @@ -570,9 +570,6 @@ KBUILD_CFLAGS += $(call cc-option,-Wno-p # disable invalid "can't wrap" optimizations for signed / pointers KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow) -# revert to pre-gcc-4.4 behaviour of .eh_frame -KBUILD_CFLAGS += $(call cc-option,-fno-dwarf2-cfi-asm) - # conserve stack if available KBUILD_CFLAGS += $(call cc-option,-fconserve-stack) Index: linux-2.6.33-rc1-ak/arch/powerpc/Makefile =================================================================== --- linux-2.6.33-rc1-ak.orig/arch/powerpc/Makefile +++ linux-2.6.33-rc1-ak/arch/powerpc/Makefile @@ -112,6 +112,11 @@ KBUILD_CFLAGS += $(call cc-option,-mspe= # kernel considerably. KBUILD_CFLAGS += $(call cc-option,-funit-at-a-time) +# FIXME: the module load should be taught about the additional relocs +# generated by this. +# revert to pre-gcc-4.4 behaviour of .eh_frame +KBUILD_CFLAGS += $(call cc-option,-fno-dwarf2-cfi-asm) + # Never use string load/store instructions as they are # often slow when they are implemented at all KBUILD_CFLAGS += -mno-string