From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from foss.arm.com ([217.140.101.70]:59219 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754672AbbKDIw6 (ORCPT ); Wed, 4 Nov 2015 03:52:58 -0500 Message-ID: <5639C763.7000707@arm.com> Date: Wed, 04 Nov 2015 08:52:51 +0000 From: Marc Zyngier MIME-Version: 1.0 To: Bharat Kumar Gogada , Amit Tomer CC: "robh+dt@kernel.org" , "pawel.moll@arm.com" , "mark.rutland@arm.com" , "ijc+devicetree@hellion.org.uk" , "galak@codeaurora.org" , Michal Simek , Soren Brinkmann , "bhelgaas@google.com" , "arnd@arndb.de" , "tinamdar@apm.com" , "treding@nvidia.com" , "rjui@broadcom.com" , "Minghuan.Lian@freescale.com" , "m-karicheri2@ti.com" , "hauke@hauke-m.de" , "dhdang@apm.com" , "sbranden@broadcom.com" , "devicetree@vger.kernel.org" , Ravikiran Gummaluri , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-pci@vger.kernel.org" Subject: Re: [PATCH v7] PCI: Xilinx-NWL-PCIe: Added support for Xilinx NWL PCIe Host Controller References: <1446564227-4704-1-git-send-email-bharatku@xilinx.com> <5638DE62.6050605@arm.com> <8520D5D51A55D047800579B09414719801693C20@XAP-PVEXMBX01.xlnx.xilinx.com> <8520D5D51A55D047800579B09414719801693C5C@XAP-PVEXMBX01.xlnx.xilinx.com> In-Reply-To: <8520D5D51A55D047800579B09414719801693C5C@XAP-PVEXMBX01.xlnx.xilinx.com> Content-Type: text/plain; charset=utf-8 Sender: linux-pci-owner@vger.kernel.org List-ID: On 04/11/15 07:54, Bharat Kumar Gogada wrote: >>> Without #ifdefs if we compile driver for legacy, MSI structures will not be >> available and we get compile time error. >> >> Sorry for nitpicking but at least can we use elegant version of #ifdefs .i.e. #if >> IS_ENABLED() here ? >> > Since IS_ENABLED() is checked at runtime, compile time error would come for legacy. You're seriously misguided. IS_ENABLED() is specifically designed *not* to be checked at runtime, but instead to use the compiler optimization phase to get rid of code sections at compile time. M. -- Jazz is not dead. It just smells funny...