From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.skyhub.de ([78.46.96.112]:60826 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751672AbaJEPck (ORCPT ); Sun, 5 Oct 2014 11:32:40 -0400 From: Borislav Petkov Subject: [PATCH] Kbuild: Check for CONFIG_READABLE_ASM when building .s targets Date: Sun, 5 Oct 2014 17:32:34 +0200 Message-Id: <1412523154-25602-1-git-send-email-bp@alien8.de> Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: linux-kbuild@vger.kernel.org Cc: Michal Marek , LKML , X86 ML From: Borislav Petkov We do need to look at the asm output of c files for various reasons. In order to do so, we do make .s. However, it can happen that the Kconfig option which enables the creation of readable asm CONFIG_READABLE_ASM is disabled. What is more, we want this option enabled because it indirectly enables the issue of line numbers in the asm done by gcc's switch -g. So issue a warning that the asm output might not be optimally readable if that option is disabled. Signed-off-by: Borislav Petkov --- Makefile | 2 +- scripts/Makefile.build | 7 ++++++- 2 files changed, 7 insertions(+), 2 deletions(-) diff --git a/Makefile b/Makefile index e43244263306..d9b505360c2a 100644 --- a/Makefile +++ b/Makefile @@ -1513,7 +1513,7 @@ else endif %.s: %.c prepare scripts FORCE - $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@) + $(Q)$(MAKE) $(build)=$(build-dir) asm_target=$@ $(target-dir)$(notdir $@) %.i: %.c prepare scripts FORCE $(Q)$(MAKE) $(build)=$(build-dir) $(target-dir)$(notdir $@) %.o: %.c prepare scripts FORCE diff --git a/scripts/Makefile.build b/scripts/Makefile.build index bf3e6778cd71..8aaf1c04fe18 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -147,7 +147,12 @@ $(multi-objs-y:.o=.s) : modname = $(modname-multi) $(multi-objs-y:.o=.lst) : modname = $(modname-multi) quiet_cmd_cc_s_c = CC $(quiet_modtag) $@ -cmd_cc_s_c = $(CC) $(c_flags) $(DISABLE_LTO) -fverbose-asm -S -o $@ $< +cmd_cc_s_c = $(CC) $(c_flags) $(DISABLE_LTO) -fverbose-asm -S -o $@ $< \ + $(if $(findstring $(asm_target),$@),\ + $(if $(__cmd_cc_s_c_once),,\ + $(if $(CONFIG_READABLE_ASM),,\ + $(warning Enable CONFIG_READABLE_ASM for more helpful asm); \ + $(eval __cmd_cc_s_c_once=1)))) \ $(obj)/%.s: $(src)/%.c FORCE $(call if_changed_dep,cc_s_c) -- 2.0.0