Re: Why does this happen?

[tmoran@acm.org]

> > Gnat 3.14 on my Windows system compiles those lines without complaint.
>
> ... but not on my Gnat 3.14, Windows NT.
> I get the same error message as OP.
  Interesting.  The declarations compile OK.  An assignment to T.M
in the body causes the error message to appear in the spec.  Dropping
Func, the body:

package body test is

   junk:mtr_type(1 .. 2, 1 .. 2);

   procedure Proc(T : in out T_Typ) is
--   junk : mtr_type := T.M;
   begin
     T.M := junk;
   end Proc;
end test;

causes the error message, but if you switch which "junk" is commented out,
Gnat gives its "I crashed" message.  Clearly a confused compiler.