On 08/06/2010 09:16 PM, Van Snyder wrote:
> On Thu, 2010-08-05 at 19:14 -0700, Vivek Rao wrote:
>> Especially someone who has proposed many features in Fortran 2008
>> should be aware that several compiler vendors have decided not to
>> produce compilers beyond Fortran 95 (except for some TR's).

Well, the question is why? In any case there is a large number of 
Fortran compilers which have implemented some parts of Fortran 2003, add 
more Fortran 2003 support and plan to complete Fortran 2003/2008 support 
at some point.

With the same argument, one should not have started Fortran 90 or moved 
to 95 as a large number of compilers stayed with Fortran 77. And even 
today, many users only use Fortran compilers for old Fortran 77 programs 
or for Fortran 90/95 programs. The latter also because the developers 
restricted themselves to those features all compiler supported. However, 
I see a change: More and more Fortran 2003 features are used - some 
deliberately and some (like non-integer initialization expressions) more 
accidentally. I think that's driven in part by the market concentration 
in terms of hardware (thus effectively, fewer compilers need to be 
supported) but also by the availability of g95/gfortran which invalidate 
excuses such as that for one platform no newer compiler exists or that 
is to expensive.

>> [...]
>> Maybe someone can comment about Pathscale.

The latest Pathscale 3.3 beta contains some Fortran 2003 features, cf. 
http://www.pathscale.com/docs/3.2.99/release_notes.txt ; I think the 
IEEE TR is also supported and some other F2003 features which were added 
before 3.3. I think the new PathScale Inc. is now spending more work on 
their Fortran compiler - and I saw that they are looking for a Fortran 
developer ... (I wrote "new PathScale" as Cray bought Pathscale from 
SiCortex (in August 2009, [1]) - and it is now developed by 
NetSyncro.com with part of the old staff; parts of the PathScale 
compiler became opensource.)

>> The committee should restrict itself to maintenance mode until full
>> F2008 compilers are available.
> Why?

Actually, why not? ;-)  [see below]

> With the exception of coarrays, Fortran 2008 was essentially a
> maintenance project.

That actually also matches my impression - I have the feeling that 
gfortran will first complete the support for the newer F2008 features 
before finishing some of the remaining Fortran 2003 tasks.* The only 
larger Fortran 2008 task seems to be coarray support but that's already 
supported to some extend by Cray, g95, gfortran (well, only one image 
and incomplete), and seemingly by Intel's 11.1. The other tasks seem to 
be relatively minor - looking at the list of features and at what 
gfortran and other compilers currently support.

(Cf. http://fortranwiki.org/fortran/show/Fortran+2008+status and for 
gfortran also http://gcc.gnu.org/wiki/Fortran2008Status )

Thus, I would not be surprised if the first so-called "full Fortran 
2008" compiler would be available around the time the draft of the 
coarray TR is finished. [So called because it will take years to find 
all those cases where minor restrictions has been lifted at various 
places in the standard.]

In that sense, I think "restrict itself to maintenance mode" and TR work 
until the first Fortran 2008 compiler is available is compatible with 
the idea of doing for about a year only maintenance and TR development.

> A significant reason that Fortran fell into bad odor in the computer
> science community between 1966 and 1990 was that it had stagnated.

And one reason that it stagnated after a couple of years after 1990 was 
the lack of compilers ...

> If ANSI and ISO committees had taken Vivek's advice in 2004 (and there
> were others offering the same advice), Fortran 2008 wouldn't have
> co-arrays, which are an enormous leap forward compared to PVM or MPI or
> HPC or OpenMP.

While I do like coarrays, I do not see them as being "an enormous leap 
forward"; they make Fortran more attractive, they offer some nice 
features and integrate nicely into the language, but one has to do the 
same effort as with MPI to parallelize the code. (The coarray syntax 
seems to be easier, but the structure of the program is the same as with 
MPI.)

Bill Long wrote:
> Language standardization takes a long time. By its very nature, it is 
> always "ahead" of the average user of the language.

Surprisingly, it is usually also ahead of compiler implementation and 
ahead of advanced users ;-)

Tobias

[1] 
http://investors.cray.com/phoenix.zhtml?c=98390&p=irol-newsArticle&ID=1324995&highlight=

* GCC: The changes which are in the GCC development version (4.6.0) are 
listed at http://gcc.gnu.org/gcc-4.6/changes.html#Fortran  While the 
Fortran 2008 list is much longer, most of them are small items which 
could be implemented quickly - contrary to the on-going Fortran 2003 work.