A compilation problem with Dec compiler?

[contr47@nosc-tecr.UUCP ("CONTR47")]

Here is a compilation problem reported by Greg Saunders.
The following is a simplied instance of the problem. The
following code compiled ok on Data General and NYU Ada/Ed-C.
 Note it is a warning, not a hard error but I suspect the result
is useless anyway.
Any idea what is going on here? Should it be added to
validation suite?
regards, sam harbaugh
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A                                                               16-Nov-1986 12:38:53    VAX Ada V1.2-15                     Page   1
01                                                              16-Nov-1986 12:38:37    DRB2:[CONTR47]GREGTEST.ADA;6             (1)

    1 	Package A is 
    2 	 procedure B;
    3 	  generic 
    4 	    type Y is digits <>; 
    5 	  Package D is 
    6 	     z:integer;
    7 	  end D;
    8 	  type Q is digits 6;
    9 	  Package DD is new D(Q);
..........1
%ADAC-W-INSTINCOMPL, (1) Instantiation incomplete because template for generic package declaration D at line 3 is not 
        available

   10 	end A;
%ADAC-I-CL_ADDED, Package specification A added to library
    Replaces older version compiled 16-Nov-1986 12:36

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