Re: [Patch, Fortran] PR fortran/83522 – reject array-valued substrings

Re: [Patch, Fortran] PR fortran/83522 – reject array-valued substrings

[Thomas Koenig]

Hi Tobias,

nice to hear from you again!

> Build and regtested on x86_64-linux.
> OK for the trunk?

OK. Thanks for the patch!

Regards

	Thomas

Re: [Patch, Fortran] PR fortran/83522 – reject array-valued substrings

[Paul Richard Thomas]

This seems to have caused errors in the testsuite. I guess that the
problem is that the testcases are invalid :-(

From David Edelsohn:
Error: Substring reference of nonscalar not permitted at (1)

arrayio_11.f90
arrayio_12.f90
associate_23.f90
data_char_1.f90
deferred_character_2.f90
deferred_character_22.f90
deferred_character_23.f90
deferred_character_8.f90
deferred_type_component_3.f90

Cheers

Paul

On Mon, 8 Oct 2018 at 23:16, Thomas Koenig <tkoenig@netcologne.de> wrote:
>
> Hi Tobias,
>
> nice to hear from you again!
>
> > Build and regtested on x86_64-linux.
> > OK for the trunk?
>
> OK. Thanks for the patch!
>
> Regards
>
>         Thomas



--
"If you can't explain it simply, you don't understand it well enough"
- Albert Einstein

Re: [Patch, Fortran] PR fortran/83522 – reject array-valued substrings

[David Edelsohn]

Apparently this change also breaks CPU SPEC (465.tonto?).

Is this really a correct change?  Even if the testcases really are
wrong, it seems that this change is going to break a lot of code in
the wild.  This seems like a very bad choice, even if it pedantically
is correct.

Thanks, David

On Wed, Oct 10, 2018 at 7:12 PM Paul Richard Thomas
<paul.richard.thomas@gmail.com> wrote:
>
> This seems to have caused errors in the testsuite. I guess that the
> problem is that the testcases are invalid :-(
>
> From David Edelsohn:
> Error: Substring reference of nonscalar not permitted at (1)
>
> arrayio_11.f90
> arrayio_12.f90
> associate_23.f90
> data_char_1.f90
> deferred_character_2.f90
> deferred_character_22.f90
> deferred_character_23.f90
> deferred_character_8.f90
> deferred_type_component_3.f90
>
> Cheers
>
> Paul
>
> On Mon, 8 Oct 2018 at 23:16, Thomas Koenig <tkoenig@netcologne.de> wrote:
> >
> > Hi Tobias,
> >
> > nice to hear from you again!
> >
> > > Build and regtested on x86_64-linux.
> > > OK for the trunk?
> >
> > OK. Thanks for the patch!
> >
> > Regards
> >
> >         Thomas
>
>
>
> --
> "If you can't explain it simply, you don't understand it well enough"
> - Albert Einstein

Re: [Patch, Fortran] PR fortran/83522 – reject array-valued substrings

[David Edelsohn]

Another data point: I tried some of the testcases with IBM XL Fortran
compiler and it didn't complain or fail.  I have no idea if this
behavior is an IBM extension or how other Fortran compilers behave.

GNU Fortran probably should be compatible with other Fortran
compilers, even if the behavior is not pedantically conformant with
the standard.

Thanks, David

On Wed, Oct 10, 2018 at 7:12 PM Paul Richard Thomas
<paul.richard.thomas@gmail.com> wrote:
>
> This seems to have caused errors in the testsuite. I guess that the
> problem is that the testcases are invalid :-(
>
> From David Edelsohn:
> Error: Substring reference of nonscalar not permitted at (1)
>
> arrayio_11.f90
> arrayio_12.f90
> associate_23.f90
> data_char_1.f90
> deferred_character_2.f90
> deferred_character_22.f90
> deferred_character_23.f90
> deferred_character_8.f90
> deferred_type_component_3.f90
>
> Cheers
>
> Paul
>
> On Mon, 8 Oct 2018 at 23:16, Thomas Koenig <tkoenig@netcologne.de> wrote:
> >
> > Hi Tobias,
> >
> > nice to hear from you again!
> >
> > > Build and regtested on x86_64-linux.
> > > OK for the trunk?
> >
> > OK. Thanks for the patch!
> >
> > Regards
> >
> >         Thomas
>
>
>
> --
> "If you can't explain it simply, you don't understand it well enough"
> - Albert Einstein

Re: [Patch, Fortran] PR fortran/83522 – reject array-valued substrings

[Paul Richard Thomas]

The section from the standard in comment #2 is being misinterpreted.
R609 and R610 concern substrings in the context of section 6.4, which
concerns SCALARS!

Section 6.5 concerns arrays and you will find there:

R618 array-section is data-ref [ ( substring-range ) ] or
complex-part-designator

C624 (R618) Exactly one part-ref shall have nonzero rank, and either
the final part-ref shall have a section-
subscript-list with nonzero rank, another part-ref shall have nonzero
rank, or the complex-part-designator
shall be an array.

Further lines appear later in which in which substrings of array
sections are explicitly mentioned: eg.
If a substring-range appears in an array-section, each element is the
designated substring of the corresponding element of the array
section. The value of a subscript in an array element shall be within
the bounds for its dimension.

Thus the patch is contrary to the standard and must be removed as soon
as possible.

Paul


On Thu, 11 Oct 2018 at 15:20, David Edelsohn <dje.gcc@gmail.com> wrote:
>
> Another data point: I tried some of the testcases with IBM XL Fortran
> compiler and it didn't complain or fail.  I have no idea if this
> behavior is an IBM extension or how other Fortran compilers behave.
>
> GNU Fortran probably should be compatible with other Fortran
> compilers, even if the behavior is not pedantically conformant with
> the standard.
>
> Thanks, David
>
> On Wed, Oct 10, 2018 at 7:12 PM Paul Richard Thomas
> <paul.richard.thomas@gmail.com> wrote:
> >
> > This seems to have caused errors in the testsuite. I guess that the
> > problem is that the testcases are invalid :-(
> >
> > From David Edelsohn:
> > Error: Substring reference of nonscalar not permitted at (1)
> >
> > arrayio_11.f90
> > arrayio_12.f90
> > associate_23.f90
> > data_char_1.f90
> > deferred_character_2.f90
> > deferred_character_22.f90
> > deferred_character_23.f90
> > deferred_character_8.f90
> > deferred_type_component_3.f90
> >
> > Cheers
> >
> > Paul
> >
> > On Mon, 8 Oct 2018 at 23:16, Thomas Koenig <tkoenig@netcologne.de> wrote:
> > >
> > > Hi Tobias,
> > >
> > > nice to hear from you again!
> > >
> > > > Build and regtested on x86_64-linux.
> > > > OK for the trunk?
> > >
> > > OK. Thanks for the patch!
> > >
> > > Regards
> > >
> > >         Thomas
> >
> >
> >
> > --
> > "If you can't explain it simply, you don't understand it well enough"
> > - Albert Einstein



-- 
"If you can't explain it simply, you don't understand it well enough"
- Albert Einstein