Tucker Taft schrieb:
> The instantiations should be rejected.  A designated subtype
> is determined when an access type is declared, and is the
> same for all subtypes of the access type, even if the
> access subtypes impose constraints on the designated subtype.
> Hence, none of these match statically, because the designated
> subtype of the actual is unconstrained in each case, whereas
> the designated subtype of the formal is constrained in each case.
> RM paragraph 3.10(10) defines designated subtype, and it is
> determined completely by the subtype_indication given in the
> access type definition.  Constraints imposed on the access type
> do not change this definition.

So I do hope, Wesley, that you report this defect to Gnat because it (at
least in version 3.10p1) accepts the code.

Christoph Grein
Member of Ada Germany

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