Re: Type based aliasing

[Toon Moene <toon at moene dot indiv dot nluug dot nl>]

Robert Dewar wrote:

> <<Fortran rules don't allow arguments (which are references in g77) to
> overlap at all, so in this case, g77 would just assume (without
> checking) that *ip and *fp wouldn't overlap.
> Is that really true? I thought the rule was that if there is any aliasing
> then assignment by any alias path is forbidden (this certainly was the
> original rule in Fortran, it might have changed, but that would surprise me).
The rule is that you can't `define' a dummy argument that's 
argument-associated with another dummy argument.

`Define' in Fortran-speak is to `have a value assigned to it and all of 
the entities that are associated with it'.

Assignment is one way to cause problems here, but not the only one.

--
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