Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755730Ab3GaDRq (ORCPT ); Tue, 30 Jul 2013 23:17:46 -0400 Received: from mail-pd0-f173.google.com ([209.85.192.173]:33752 "EHLO mail-pd0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752645Ab3GaDRo (ORCPT ); Tue, 30 Jul 2013 23:17:44 -0400 Message-ID: <51F8818C.7030703@gmail.com> Date: Wed, 31 Jul 2013 11:16:28 +0800 From: Chen Gang F T User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2 MIME-Version: 1.0 To: Chen Gang CC: Joe Perches , "'Jiri Kosina'" , jaharkes@cs.cmu.edu, coda@cs.cmu.edu, codalist@TELEMANN.coda.cs.cmu.edu, "linux-kernel@vger.kernel.org" Subject: Re: [PATCH trivial] include/linux/coda.h: remove useless '#else' References: <51F76B7D.2090602@asianux.com> <1375187380.2075.111.camel@joe-AO722> <51F86C08.3080805@asianux.com> <51F86E1A.60404@asianux.com> In-Reply-To: <51F86E1A.60404@asianux.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5061 Lines: 162 On 07/31/2013 09:53 AM, Chen Gang wrote: > On 07/31/2013 09:44 AM, Chen Gang wrote: >> On 07/30/2013 08:29 PM, Joe Perches wrote: >>> On Tue, 2013-07-30 at 15:30 +0800, Chen Gang wrote: >>>> '#else' is useless, need remove. >>>> >>>> Signed-off-by: Chen Gang >>>> --- >>>> include/linux/coda.h | 1 - >>>> 1 files changed, 0 insertions(+), 1 deletions(-) >>>> >>>> diff --git a/include/linux/coda.h b/include/linux/coda.h >>>> index cff544f..d30209b 100644 >>>> --- a/include/linux/coda.h >>>> +++ b/include/linux/coda.h >>>> @@ -60,7 +60,6 @@ Mellon the rights to redistribute these changes without encumbrance. >>>> >>>> #if defined(__linux__) >>>> typedef unsigned long long u_quad_t; >>>> -#else >>>> #endif >>>> #include >>>> #endif >>> >>> Why have the #if at all? >>> >>> >>> >> OH, sorry, what I said about openrisc cross-compiler is not precise. Need a patch for openrisc (just like another architectures have done): -------------------------------diff begin------------------------------- diff --git a/arch/openrisc/Makefile b/arch/openrisc/Makefile index 4739b83..89076a6 100644 --- a/arch/openrisc/Makefile +++ b/arch/openrisc/Makefile @@ -24,7 +24,7 @@ OBJCOPYFLAGS := -O binary -R .note -R .comment -S LDFLAGS_vmlinux := LIBGCC := $(shell $(CC) $(KBUILD_CFLAGS) -print-libgcc-file-name) -KBUILD_CFLAGS += -pipe -ffixed-r10 +KBUILD_CFLAGS += -pipe -ffixed-r10 -D__linux__ ifeq ($(CONFIG_OPENRISC_HAVE_INST_MUL),y) KBUILD_CFLAGS += $(call cc-option,-mhard-mul) -------------------------------diff end--------------------------------- But for "include/linux/coda.h", I still suggest to check __linux__ whether defined, at least it can find the building issues. And next, I will send the related patch to openrisc mailing list. :-) Thanks. >> Hmm... some old version compilers do not define __linux__ automatically >> (e.g. or32-linux-gcc 4.5.1-or32-1.0rc1, which is the latest cross >> compiler for openrisc, though). >> >> If not define __linux__, the compiler will report error (u_quad_t is >> not defined). >> >> When we remove "#if defined(__linux__)" from "include/linux/coda.h", >> the compiler will not report error, and 'cdev_t' will be defined as >> 'dev_t', not 'u_quad_t' (I guess, it is an implicit bug). >> >> >> In "uapi/include/*", only "coda.h" has "#if defined(__linux__)", maybe >> they want multiple OS can share the same "coda.h" file (at least, we >> can not say it is a bad idea). >> >> Neither suitable to define __linux__ in "include/linux/coda.h". >> >> >> All together, I think: >> >> the direct cause: >> "uapi/include/coda.h" wants to share itself for multiple OS (so they need check __linux__). >> (in "uapi/include/*", only coda.h need check __linux__) >> >> the root cause: >> the compiler for linux should define __linux__ automatically, the latest version of gcc has done, but some of the old version is not. >> most of cross compilers have merged their code into gcc main tree, but still left some (e.g. openrisc). >> (at least, I can not build openrisc from gcc main tree correctly, but most of others can) >> some of latest cross compilers still use old version of gcc, (still not define __linux__ automatically). >> > > Maybe what I said is incorrect (it is just my current understanding). > > Welcome any other members' suggestions or completions for discussing and > checking. > > Thanks. > >> >> The related code in "uapi/linux/coda.h" is below: >> >> -------------------------------code begin------------------------------- >> >> 73 #if defined(DJGPP) || defined(__CYGWIN32__) >> 74 #ifdef KERNEL >> 75 typedef unsigned long u_long; >> 76 typedef unsigned int u_int; >> 77 typedef unsigned short u_short; >> 78 typedef u_long ino_t; >> 79 typedef u_long dev_t; >> 80 typedef void * caddr_t; >> 81 #ifdef DOS >> 82 typedef unsigned __int64 u_quad_t; >> 83 #else >> 84 typedef unsigned long long u_quad_t; >> 85 #endif >> 86 >> 87 #define inline >> 88 >> 89 struct timespec { >> 90 long ts_sec; >> 91 long ts_nsec; >> 92 }; >> 93 #else /* DJGPP but not KERNEL */ >> 94 #include >> 95 typedef unsigned long long u_quad_t; >> 96 #endif /* !KERNEL */ >> 97 #endif /* !DJGPP */ >> 98 >> 99 >> 100 #if defined(__linux__) >> 101 #include >> 102 #define cdev_t u_quad_t >> 103 #ifndef __KERNEL__ >> 104 #if !defined(_UQUAD_T_) && (!defined(__GLIBC__) || __GLIBC__ < 2) >> 105 #define _UQUAD_T_ 1 >> 106 typedef unsigned long long u_quad_t; >> 107 #endif >> 108 #endif /* __KERNEL__ */ >> 109 #else >> 110 #define cdev_t dev_t >> 111 #endif >> 112 >> >> -------------------------------code end--------------------------------- >> >> >> Thanks. >> > > -- Chen Gang -- 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/