(j3.2006) Question about co-arrays

Aleksandar Donev donev1
Wed Feb 7 13:05:07 EST 2007

In addition to what John said, to address specifically:
> In light of Note 5.10 [91:8+1-3]
The difference between a co-array of a derived types with pointer components 
and of type C_PTR is that the user can do something useful with pointer 
components, specifically, they can have data-refs of the form:
and the compiler knows, from the reference, that this is remote data, and will 
do the magic to get it.
On the other hand, there is nothing useful that can be done with a C pointer 
x[i], since C does not understand co-arrays and cannot fetch data from remote 
images. We specifically disallow such co-indexed pointers in C_LOC and 
C_F_POINTER because it makes no sense to claim interop for something that is 
not even part of the C standard.

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