Re: C array to ada record interface

[tmoran@acm.org]

> (PS. I have not tried to compile my example code, so there may be
> errors in it)

  Could you post a complete, running, example please?  I must have missed
something.  Here is my interpretation of such a thing, but, though it
compiles on two out of three Ada compilers I tried, it generates
(different) junk results on both.  (The third compiler objects to the
Unchecked_Conversion instantiation.)

with ada.text_io,
     Ada.Unchecked_Conversion,
     interfaces.c;
procedure testuc2 is

  type B is new integer;

  type B_Array is array(Interfaces.c.int range <>) of aliased B;

  type B_Ptr is access all B;
  pragma Convention (C, B_Ptr);

  function To_Ada_Array (Arr : in B_Ptr; Len : in Interfaces.C.int)
                        return B_Array is
    subtype Array_With_Known_Length is B_Array (1 .. Len);

    function To_Ada is new Ada.Unchecked_Conversion
       (Source => B_Ptr, Target => Array_With_Known_Length);

  begin
     return To_Ada (Arr);
  end To_Ada_Array;

  procedure show(ba : in b_array) is
  begin
    ada.text_io.put_line("ba(3)=");
    ada.text_io.put_line(b'image(ba(3)));
  end show;

  x : b_array(1 .. 5) := (others=>17);
begin

  show(to_ada_array(arr=>x(1)'access, len=>5));

end testuc2;