Boolean type not correctly generated for generic session functions

[senier]

The following spec

package Test is

   type Reserved_7 is mod 2 ** 7;
   type M is
      message
         F1 : Boolean;
         F2 : Reserved_7;
      end message;
   generic
      with function Func (Arg : Boolean) return Boolean;                                                               
   session S with
      Initial => S1,
      Final   => Done
   is
   begin
      state S1 is
         Message : M;
         Value   : Boolean;
      begin
         Value := Func (True);
         Message := M'(F1 => Value, F2 => 0);                                                                          
      transition
         goto Done
      exception
         goto Done
      end S1;
      state Done is null state;
   end S;
end Test;

results in this session code:

generic
   with procedure Func (Func : out RFLX.__BUILTINS__.Boolean; Arg : RFLX.__BUILTINS__.Boolean);
package RFLX.Test.S with
  SPARK_Mode,
  Initial_Condition =>
    Uninitialized
is
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