Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753162AbbFRHKi (ORCPT ); Thu, 18 Jun 2015 03:10:38 -0400 Received: from mail-oi0-f43.google.com ([209.85.218.43]:35653 "EHLO mail-oi0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751933AbbFRHKb (ORCPT ); Thu, 18 Jun 2015 03:10:31 -0400 MIME-Version: 1.0 In-Reply-To: <55826966.6050202@synopsys.com> References: <55826966.6050202@synopsys.com> Date: Thu, 18 Jun 2015 09:10:30 +0200 X-Google-Sender-Auth: ssZph7VtfrZNt5a7KntMryNr32U Message-ID: Subject: Re: subtle side effect of commit a1c48bb160f836 From: Geert Uytterhoeven To: Vineet Gupta Cc: Michal Marek , "linux-arch@vger.kernel.org" , lkml Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1496 Lines: 37 Hi Vineet, On Thu, Jun 18, 2015 at 8:47 AM, Vineet Gupta wrote: > commit a1c48bb160f8368 "Makefile: Fix unrecognized cross-compiler command line > options" moved ARCH specific cc option handling before common -Os/O2 setup. > > For ARC this had a subtle effect that we can no longer over-ride generic -O2 with > -O3, hence a performance regression observed going from 3.13 to 3.18 (the above > commit went into 3.16) > > I want to understand how to properly fix this. Moving the include of arch makefile > will bring back the old issue. I can introduce another option to set default optim > level, but only arc/m32r care about it anyways. Can we include $(srctree)/arch/$(SRCARCH)/Makefile twice? Or perhaps we can not apply the extra -O* if there's already a -O* option? Alternatively, as we already have CONFIG_CC_OPTIMIZE_FOR_SIZE, a(nother) Kconfig option may make sense. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/