(j3.2006) 07-276r1

[Bill Long]

Malcolm Cohen wrote:
> On Sat, 29 Sep 2007 06:25:33 +0900, Aleksandar Donev <donev1 at llnl.gov>  
> wrote:
>   
>> Apparently Malcolm rejected the edit in 07-267r1:
>>     
>
> And with good reason.
>
>
>   
....

> Just what C variable is
>
>    REAL,BIND(C,NAME='fred') :: x[10,*]
>
> meant to interoperate with?
>
> i.e. the problem is not limited to dummies, it is completely analogous
> to ALLOCATABLEs, and we solved it for ALLOCATABLEs by not making them
> interoperable too.
>
>   

I think this example helps explain Malcolm's objection to the original 
edit.   A co-array might have some storage constraints, and they might 
be incompatible with the way C stores globals. They might be in 
different data segments, for example.  Until we get more experience with 
a range of co-array implementations, it is safer to just make co-arrays 
not interoperable.  If it turns out to be a non-issue,  we can relax the 
constraint in the future.

Cheers,
Bill

-- 
Bill Long                                   longb at cray.com
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