[Octave-bug-tracker] [bug #59602] incorrect "not a direct superclass" error

[Ray Zimmerman]

URL:
  <https://savannah.gnu.org/bugs/?59602>

                 Summary: incorrect "not a direct superclass" error
                 Project: GNU Octave
            Submitted by: rdzman
            Submitted on: Wed 02 Dec 2020 08:31:28 PM UTC
                Category: Interpreter
                Severity: 3 - Normal
                Priority: 5 - Normal
              Item Group: Unexpected Error or Warning
                  Status: None
             Assigned to: None
         Originator Name: 
        Originator Email: 
             Open/Closed: Open
                 Release: 6.0.90
         Discussion Lock: Any
        Operating System: Mac OS

    _______________________________________________________

Details:

Given the following two classes ...


classdef classA < classB
    properties
        a = @classB;
    end
    methods
        function obj = classA()
            obj@classB();
        end
    end
end



classdef classB < handle
end


... attempting to instantiate *classA* in a fresh Octave session results in
the following error:


octave:1> a = classA
error: 'classB' is not a direct superclass of 'classA'
error: called from
    classA at line 7 column 13


While it produces this error consistently in a fresh Octave session, the code
does sometimes work fine, depending on previous activity in the Octave
session. For example, the following is also repeatable for me in a fresh
Octave session:


octave:1> b = @classB
b = @classB
octave:2> a = classA
a =

  classA object with properties:

      a: [1x1 function_handle]


In my tests on previous versions (e.g. 5.2.0, 5.1.0, 4.4.1) I was not able to
reproduce the error. In 6.0.09 the error seems to be related to the
initialization of the property a in classA. Initializing it with a different
value also eliminates the error.

Very strange ... this bug was causing nondeterministic results from the test
suite for my own code, and it took me hours to boil it down to this MWE.




    _______________________________________________________

Reply to this item at:

  <https://savannah.gnu.org/bugs/?59602>

_______________________________________________
  Message sent via Savannah
  https://savannah.gnu.org/