From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 11388 invoked by alias); 23 May 2012 07:56:52 -0000 Received: (qmail 11369 invoked by uid 22791); 23 May 2012 07:56:50 -0000 X-SWARE-Spam-Status: No, hits=-1.6 required=5.0 tests=AWL,BAYES_00,KHOP_RCVD_UNTRUST,KHOP_THREADED,RCVD_IN_DNSWL_LOW,RCVD_IN_HOSTKARMA_NO X-Spam-Check-By: sourceware.org Received: from service87.mimecast.com (HELO service87.mimecast.com) (91.220.42.44) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 23 May 2012 07:56:36 +0000 Received: from cam-owa2.Emea.Arm.com (fw-tnat.cambridge.arm.com [217.140.96.21]) by service87.mimecast.com; Wed, 23 May 2012 08:56:33 +0100 Received: from [10.1.69.67] ([10.1.255.212]) by cam-owa2.Emea.Arm.com with Microsoft SMTPSVC(6.0.3790.3959); Wed, 23 May 2012 08:56:40 +0100 Message-ID: <4FBC982F.7040403@arm.com> Date: Wed, 23 May 2012 07:56:00 -0000 From: Richard Earnshaw User-Agent: Mozilla/5.0 (X11; Linux i686 on x86_64; rv:11.0) Gecko/20120327 Thunderbird/11.0.1 MIME-Version: 1.0 To: Andreas Jaeger CC: Michael Hope , "cross-distro@lists.linaro.org" , Carlos O'Donell , GCC Patches , "libc-ports@sourceware.org" , Richard Guenther Subject: Re: [PATCH v2] ARM: Use different linker path for hardfloat ABI References: <4F9576DE.9070608@arm.com> <4F9EAE9D.3040509@arm.com> <4F9FA448.6090509@arm.com> <4FBC8DCB.6020006@suse.com> In-Reply-To: <4FBC8DCB.6020006@suse.com> X-MC-Unique: 112052308563308201 Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Mailing-List: contact libc-ports-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: libc-ports-owner@sourceware.org X-SW-Source: 2012-05/txt/msg00134.txt.bz2 On 23/05/12 08:12, Andreas Jaeger wrote: > On 05/01/2012 10:52 AM, Richard Earnshaw wrote: >> On 30/04/12 22:47, Michael Hope wrote: >>> On 1 May 2012 03:24, Richard Earnshaw wrote: >>>> On 27/04/12 00:27, Michael Hope wrote: >>>>> On 27 April 2012 08:20, Carlos O'Donell wro= te: >>>>>> On Mon, Apr 23, 2012 at 5:36 PM, Michael Hope wrote: >>>>>>> 2012-04-24 Michael Hope >>>>>>> Richard Earnshaw >>>>>>> >>>>>>> * config/arm/linux-eabi.h (GLIBC_DYNAMIC_LINKER_SOFT_FLOAT)= : Define. >>>>>>> (GLIBC_DYNAMIC_LINKER_HARD_FLOAT): Define. >>>>>>> (GLIBC_DYNAMIC_LINKER_DEFAULT): Define. >>>>>>> (GLIBC_DYNAMIC_LINKER): Redefine to use the hard float path. >>>>>>> >>>>>>> diff --git a/gcc/config/arm/linux-eabi.h b/gcc/config/arm/linux-eab= i.h >>>>>>> index 80bd825..2ace6f0 100644 >>>>>>> --- a/gcc/config/arm/linux-eabi.h >>>>>>> +++ b/gcc/config/arm/linux-eabi.h >>>>>>> @@ -62,7 +62,17 @@ >>>>>>> /* Use ld-linux.so.3 so that it will be possible to run "classic" >>>>>>> GNU/Linux binaries on an EABI system. */ >>>>>>> #undef GLIBC_DYNAMIC_LINKER >>>>>>> -#define GLIBC_DYNAMIC_LINKER "/lib/ld-linux.so.3" >>>>>>> +#define GLIBC_DYNAMIC_LINKER_SOFT_FLOAT "/lib/ld-linux.so.3" >>>>>>> +#define GLIBC_DYNAMIC_LINKER_HARD_FLOAT "/lib/ld-linux-armhf.so.3" >>>>>>> +#if TARGET_DEFAULT_FLOAT_ABI =3D=3D ARM_FLOAT_ABI_HARD >>>>>>> +#define GLIBC_DYNAMIC_LINKER_DEFAULT GLIBC_DYNAMIC_LINKER_HARD_FLO= AT >>>>>>> +#else >>>>>>> +#define GLIBC_DYNAMIC_LINKER_DEFAULT GLIBC_DYNAMIC_LINKER_SOFT_FLO= AT >>>>>>> +#endif >>>>>>> +#define GLIBC_DYNAMIC_LINKER \ >>>>>>> + "%{mfloat-abi=3Dhard:" GLIBC_DYNAMIC_LINKER_HARD_FLOAT "} \ >>>>>>> + %{mfloat-abi=3Dsoft*:" GLIBC_DYNAMIC_LINKER_SOFT_FLOAT "} \ >>>>>>> + %{!mfloat-abi=3D*:" GLIBC_DYNAMIC_LINKER_DEFAULT "}" >>>>>>> >>>>>>> /* At this point, bpabi.h will have clobbered LINK_SPEC. We want= to >>>>>>> use the GNU/Linux version, not the generic BPABI version. */ >>>>>> >>>>>> This patch is broken. Please fix this. >>>>>> >>>>>> You can't use a named enumeration in cpp equality. >>>>>> >>>>>> The type ARM_FLOAT_ABI_HARD is a named enumeration and evaluates to 0 >>>>>> as an unknown identifier. >>>>>> >>>>>> Therefore "#if TARGET_DEFAULT_FLOAT_ABI =3D=3D ARM_FLOAT_ABI_HARD" >>>>>> evaluates to "#if 0 =3D=3D 0" and is always true. >>>>>> >>>>>> Watch out that "#define ARM_FLOAT_ABI_HARD ARM_FLOAT_ABI_HARD" for >>>>>> such enums is not conforming C99/C11. >>>>>> >>>>>> I suggest you define the types as macros and then set the named enum >>>>>> to those values, then use the macros in the header equality checks. >>>>>> >>>>>> e.g. >>>>>> #define VAL1 0 then enum FOO { RVAL1 =3D VAL1, ... } >>>>>> >>>>>> Look at arm.h for the enum definition. >>>>> >>>>> I've looked further into this and I think the original pre-#if version >>>>> is correct. >>>>> >>>>> The float ABI comes from these places: >>>>> * The -mfloat-abi=3D command line argument, else >>>>> * The --with-float=3D configure time argument, else >>>>> * TARGET_DEFAULT_FLOAT_ABI from linux-eabi.h >>>>> >>>>> In the first case the ABI is explicit. In the second >>>>> OPTION_DEFAULT_SPECS turns the configure time argument into an explict >>>>> -mfloat-abi=3D. >>>>> >>>>> The patch below covers all cases, keeps the logic in the spec file, >>>>> and adds a comment linking the two #defines. >>>>> >>>>> Tested by building with no configure flags, --wtih-float=3Dsoftfp, >>>>> --with-float=3Dhard, and then running with all combinations of >>>>> {,-mfloat-abi=3Dsoftfp,-mfloat-abi=3Dhard} {,-mglibc,-muclibc,-mbioni= c}. >>>>> >>>>> OK? >>>>> >>>>> -- Michael >>>>> >>>>> 2012-04-27 Michael Hope >>>>> >>>>> * config/arm/linux-eabi.h (GLIBC_DYNAMIC_LINKER): Pick the loa= der >>>>> using a spec rule. >>>>> >>>> >>>> Michael, >>>> >>>> can you try this patch please. It should make it possible to then >>>> create linux-eabihf.h containing just >>>> >>>> #undef TARGET_DEFAULT_FLOAT_ABI >>>> #define TARGET_DEFAULT_FLOAT_ABI ARM_FLOAT_ABI_HARD >>>> #undef GLIBC_DYNAMIC_LINKER_DEFAULT >>>> #define GLIBC_DYNAMIC_LINKER_DEFAULT GLIBC_DYNAMIC_LINKER_HARD_FLOAT >>>> >>>> Which is not quite as simple as leaving out the second re-define, but >>>> pretty close. >>> >>> Hi Richard. Your patch tests just fine. I like it. You could change >>> the spec rule to the newer if-elseif-else form but that's a nit. >>> >>> -- Michael >>> >> >> Great, thanks! I've committed it as is. >=20 > I suggest to add this also to the gcc 4.7 branch. Richard (Earnshaw),=20 > could you do take care of this, please? This is a behaviour change. It would need RM approval for a release branch. R.