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On Jun 7, 2004, at 5:11 PM, Richard Maine wrote: > --On Monday, June 7, 2004 4:01 PM +0200 Drew McCormack > <[log in to unmask]> wrote: > >> We have a compiler that is causing trouble when a pointer to an array >> is passed to a f77-like implicit function. It seems it is probably >> just >> passing the memory address of the pointer object, rather than doing a >> copy-in/copy-out, or something like that. > > I'll repeat one of my most common statements about requests for > debugging > help - I need data, not conclusions. I can't really comment on the > above, > as it pretty much has no data - just conclusions, with no way for me to > verify them. That's why I provided a concrete example. That said, my example omitted the most important thing, the pointer :-( It should be like this: real, target :: vertices(3, 3) real, pointer :: vpoint(:,:) real :: area, calcArea ... vpoint => vertices(1:2,:) area = calcArea( vpoint ) ... ! In another file, with an implicit interface real function calcArea( a ) real :: a(2, 3) ... end function I think that is right now. When I think about it, it is a little bit more involved, because the target array is actually a member of a user-defined type, which has the target attribute. Ie type ( SomeType ), target :: parent vpoint => parent % vertices(1:2, :) > > I see nothing wrong with the above code. I also see no pointers in it, > which leads me to be even more dubious of drawing any conclusions based > on the first para. Do you actually mean pointers or something else > that > you'd expect to be implemented sort of like pointers? Well, that's > just > a rhetorical question that I don't really expect an answer to; just > trying to illustrate how little the first para tells me. I did mean pointers, I just wrote down the wrong example basically. > > By the way, the standard doesn't require copy-in/copy-out; it is just > that > that's by far the simplest way to implement some things. When I read > the > first para, my initial thought was that you expected copy-in/copy-out > to > happen and had code that depended on that, perhaps even for contiguous > actual arguments, where many compilers optimize the copies away. But > the > code sample has a noncontiguous actual, so perhaps that wasn't the > issue. I realize it doesn't require copy-in/copy-out, that's why I included the text "...or something like that..." ;-) Sorry my original example was so wrong. Drew ======================================== Dr. Drew McCormack (Kmr. R153) Afd. Theoretische Chemie Faculteit Exacte Wetenschappen Vrije Universiteit Amsterdam De Boelelaan 1083 1081 HV Amsterdam The Netherlands Email [log in to unmask] Web www.maniacalextent.com Telephone +31 20 44 47623 Mobile +31 6 483 21307 Fax +31 20 44 47629