<br><tt><font size=2>j3-bounces@j3-fortran.org wrote on 09/22/2008 02:44:06
PM:<br>
<br>
> I understand the reasoning behind 08-267, but I'm not sure I understand<br>
> all the ramifications.<br>
> <br>
> If one can't reference a coindexed object that is polymorphic, or
that<br>
> has an allocatable ultimate component that is polymorphic or has a<br>
> length parameter, why allow such objects to have codimensions in the<br>
> first place?<br>
</font></tt>
<br>
<br><tt><font size=2>Back to 2007-08 London meeting, I've submitted a report
(Canadian National report, if I remember correctly) saying that coarrays
with OO and PDT is potentially a dangerous combination that may cause grief
in implementation and applications, and we should be looking at option
to forbid it. But back then without any concrete evidence, we simply
convinced ourselves that this was only fear, not reality.</font></tt>
<br>
<br>
<br><tt><font size=2>> <br>
> Shouldn't the restriction be on declaring such objects, not on<br>
> referencing them?<br>
> <br>
> If we can't declare or reference such objects, it seems that coarrays<br>
> are essentially built on Fortran 95, not Fortran 2003. Is this
the<br>
> intent?<br>
</font></tt>
<br>
<br><tt><font size=2>Coarrays are for performance, and polymorphism is,
in general, hurting performance (although I'm not against the OO features
in F2003). Don't know anything about PDT in real applications --
does anyone know? From this angle, why would anyone use coarrays
with OO polymorphism? Maybe Cray can provide good reasons.</font></tt>
<br>
<br><tt><font size=2>Cheers,</font></tt>
<br>
<br><font size=2 face="sans-serif">Jim Xia<br>
<br>
RL Fortran Compiler Test<br>
IBM Toronto Lab at 8200 Warden Ave, Markham, On, L6G 1C7<br>
Phone (905) 413-3444 Tie-line 313-3444<br>
email: jimxia@ca.ibm.com<br>
D2/YF7/8200 /MKM</font>
<br>