Re: [PATCH PR Fortran/89286] Intrinsic sign and GNU Extension

[Jeff Law <law@redhat.com>]

On 7/11/19 6:16 AM, Mark Eggleston wrote:
> 
> On 10/07/2019 17:20, Bernhard Reutner-Fischer wrote:
>> On 10 July 2019 17:52:40 CEST, Steve Kargl
>> <sgk@troutmask.apl.washington.edu> wrote:
>>> On Wed, Jul 10, 2019 at 02:50:47PM +0100, Mark Eggleston wrote:
>>>> The attached patch treats the intrinsic SIGN in the same way as MOD
>>> and
>>>> DIM as it has the same arguments.
>>>>
>>>> Tested using make -j 8 check-fortran on x86_64
>>>>
>>>> Conditional compilation using #ifdef __GFC_REAL_16__ has been
>>> employed
>>>> where appropriate in the test cases so should be OK on platforms
>>> without
>>>> REAL(16).
>>>>
>>>> Change logs:
>>>>
>>>> gcc/fortran
>>>>
>>>>       Mark Eggleston  <mark.eggleston@codethink.com>
>>>>
>>>>       PR fortran/89286
>>>>           * check.c (gfc_check_sign): Deleted.
>> ChangeLog has to be in present tense per convention.
>>
>>>>       * intrinsic.c (add_functions): Call add_sym_2 with gfc_check_a_p
>>>>       instead of gfc_check_sign for "sign".
>>>>       * intrinsic.h: Remove declaration of gfc_check_sign.
>>>>       * iresolve.c (gfc_resolve_sign): Check for largest kind of the
>>> actual
>>>>       arguments and convert the smaller. Set return kind to be the
>>> largest.
>>>>       * simplify.c (gfc_simplify_sign): Use the largest kind of the
>>> actual
>>>>       arguments for return
>>>>       * intrinsic.texi: Add GNU extension notes for return value to
>>> SIGN.
>>>> gcc/testsuite
>>>>
>>>>       Mark Eggleston <mark.eggleston@codethink.com>
>>>>
>>>>       PR fortran/89240
>>>>       * gfortran.dg/sign_gnu_extension_1.f90: New test.
>>>>       * gfortran.dg/sign_gnu_extension_2.f90: New test.
>>>>       * gfortran.dg/pr78619.f90: Check for "must have" instead of
>>> "must be".
>>>> If OK please can someone commit as I do not have the privileges.
>>>>
>>> We really need to get you commit access to the tree.
>>>
>>> I also am not a fan of this type of change.  Having spent the
>>> last few days working on fixing BOZ to conform to F2018, I'm
>>> finding all sorts of undocumented "extensions".  Personally,
>>> I think gfortran should be moving towards the standard by
>>> deprecating of these types of extensions.
> 
> I agree.
> 
> I think that -std=gnu should not be the default, if gnu extensions are
> required you have to ask for them.
> 
>> At least make them explicit under explicit extension or at least
>> -legacy or whatever its called.
>>
>> thanks,
> 
> I agree, at the moment the GNU extension is silently supported by DIM
> and MOD
So if Mark was to put this behavior behind the -fdec or whatever the
appropriate switch is, could this move forward?

jeff