Question Exception with Ada.Containers.Generic_Constrained_Array_Sort

[awdorrin <awdorrin@gmail.com>]

I had this code working, but today I started getting 'length check failed' exceptions.

I'm trying to implement a Generic_Constrained_Array_Sort to sort a slice of a constrained array.

Now I'm not sure if it is possible to pass a slice of the array into the constrained generic sort procedure.

Its possible I broke something somewhere else in the code that was related to this, but I haven't been able to track it down yet.

Here is what I'm trying to do:

procedure DXSort is new Ada.Containers.Generic_Constrained_Array_Sort(
  Index_Type   => Device_Index_Type,
  Element_Type => Device_Object_Type,
  Array_Type   => Device_Array_Type,
  "<"          => DevName_Less_Than);

With the following declarations:

  type Node_Rec_Type is private;
  type Node_Ptr_Type is access Node_Rec_Type;
  subtype Device_Object_Type is Node_Ptr_Type;
  subtype Device_Index_Type is Int32 range 1 .. 128;
  type Device_Array_Type is array(Device_Index_Type) of Device_Object_Type;

The comparison function is:

  function DevName_Less_Than( L,R : Device_Object_Type) return Boolean is
  begin
    if GetDeviceName(L) < GetDeviceName(R)
    then
      return TRUE;
    else
      return FALSE;
    end if;
  end DevName_Less_Than;

I make the call to the DXSort procedure with the following call:

  DXSort( DevList.DeviceList(1..DevList.Num_Devices) );
 
Num_Devices is always less than 128.

DevList is a record defined as:

  type DevListType is record
    Num_Devices : Int32;
    DeviceList  : Device_Array_Type;
  end record;

I thought that the issue might have to do with having 'Num_Devices' of type 'Int32' in the record, but defining the 'Device_Index_Type' subtype, but experimenting with changing the type still left me with 'length check failed'.

Any suggestions would be greatly appreciated! :)

-Al