Compile time error when second parameter of an overloaded procedure is null

***************************code***************************
create or replace
PACKAGE BODY MSG_DLM_PROCESS AS

  PROCEDURE p_process
    (p_espear_trade_no_in IN CHAR,
    p_ctxt_in            IN MSG_BE.t_gtx_ctxt
    ) AS

  BEGIN
      null;
  EXCEPTION
            WHEN others
            THEN
            dbms_output.put_line('error raised '||sqlerrm);
  END p_process;
/********************************overloaded p_process********************************/
  PROCEDURE p_process
  (
    p_espear_trade_no_in IN CHAR,
    p_ctxt_in            IN MSG_BE.t_atd_ctxt ) AS
  BEGIN
      null;
  EXCEPTION

            WHEN othres
            THEN
            dbms_output.put_line('error raised '||sqlerrm);
  END p_process;

END MSG_DLM_PROCESS;

=================================
My test case:p_test_case_3_gtx testing what happens when the second parameter is null
=================================

PROCEDURE p_test_case_3_gtx
IS
  v_part_key_ctxt MSG_DLM_CACHE.t_partition_key_context;
  v_part_key NUMBER;
BEGIN
  FOR v_BusinessEvent IN
  (SELECT
    /*+ index(GOOD_TRADES_XML_INDX_003)*/
    *
     FROM GOOD_TRADES_XML
    WHERE rownum<2
  )
  LOOP
      --passing second parameter as null to MSG_DLM_PROCESS.p_process. compilation error comes in this procedure.
      --I want a run time error that is handled by an exception handler of this procedure in the when others block.
    MSG_DLM_PROCESS.p_process(v_BusinessEvent.TRANS_TRADEID_TRADEIDVALUE,null);
  END LOOP;
EXCEPTION
WHEN OTHERS THEN
  dbms_output.put_line('Test Case 3 FAILED - ' || sqlcode ||' : '||sqlerrm);
END p_test_case_3_gtx;

i am just surprised and thinking as to why you want to call a procedure which has one arugment with two parameters ? what is the reason behind this ?

nav_kum_v:
I am preparing a test case. Just in case one parameter is passed and another one is not passed.

>I am preparing a test case. Just in case one parameter is passed and another one is not passed.

But, you've proven that can never happen because it won't compile.  

Now, if your test case is that two parameters are passed, but one of them is null, then you have a valid test case.  The solution is to pass two variables to the called procedure, setting either one or both to null first.  

Can you try the below to see if the below can work for you. We are basically passing null but casting it to a datatype which it can detect to avoid the error.

  MSG_DLM_PROCESS.p_process(v_BusinessEvent.TRANS_TRADEID_TRADEIDVALUE,
   cast(null as MSG_BE.t_gtx_ctxt) ); -- to call the first procedure

  MSG_DLM_PROCESS.p_process(v_BusinessEvent.TRANS_TRADEID_TRADEIDVALUE,
   cast(null as MSG_BE.t_atd_ctxt ) ); -- to call the second procedure

dgmg:
The solution is to pass two variables to the called procedure, setting either one or both to null first.  

If I initialize one of the variables to null and the set the variable as a parameter to the procedure, the program works why? Why does't oracle sense that the parameter is null now?

>Why does't oracle sense that the parameter is null now?

Because it's not an error to pass a null parameter.  The question is, what does the subroutine do when it receives the null?  If you want to that condition to raise an error, then test for null and raise the error.  But often, it's preferable to take some default action when you pass the null.

When the subroutine gets a null parameter, it raises an exception:
RAISE_APPLICATION_ERROR(..);

we can handle it accordingly in the exception section