BUG: Changing Implemented Class Does Not Give Compatibility Erro

ID: Q190967

The information in this article applies to:

Microsoft Visual Basic Professional and Enterprise Editions for Windows, versions 5.0, 6.0

SYMPTOMS

If a Visual Basic Class implements an interface of a referenced dll, then the implemented dll is removed and replaced with a different dll which contains the same interface names as the first reference, an incompatibility error is not generated when recompiling the dll with Binary Compatibility set.

For example, if Project1.dll implements Class1 in MyFirst.dll, then the reference to MyFirst.dll is removed and replaced with a reference to MySecond.dll (which also contains a Class1), recompiling Project1 does not generate a compatibility error.

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. We are researching this bug and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

Steps to Reproduce

1. Create a new ActiveX DLL Project in Microsoft Visual Basic. Class1 will

   be created by default.

2. Select Project Properties from the Project menu.

3. Change the Project Name to "Ref1."

4. Paste the following code into Class1's code window.

      Public Sub Test()
      End Sub

5. Compile Ref1.Dll by selecting Make Ref1.Dll from the File menu.

6. Return to the Project Properties and change the Project name to "Ref2."

7. In the Project Properties dialog, click on the Component Tab and select

   No Compatibility.

8. Make Ref2.dll by selecting Make Ref1 from the File menu.

   NOTE: You will need to manually change the dll name from Ref1.dll to
   Ref2.dll.

9. Create a new ActiveX dll project in Visual Basic.

10. Rename Class1 to "ClassX."

11. Select References from the Project menu, and add a reference to Ref1.

12. Paste the following into ClassX's code window:

      Implements Class1

      Private Sub Class1_Test()
      End Sub

13. Compile Project1.dll by selecting Make Project1 from the File menu.

14. Select Project Properties from the Project Menu, and then select the

   component tab. Set Binary Compatibility with Project1.dll.

15. Select References from the Project menu, remove the reference to Ref1,

   and add a reference to Ref2.

16. Compile as Project2.dll. Note that the project compiles fine, whereas

   there should be an incompatibility error.

Additional query words: kbDSupport kbVBp600bug kbVBp500bug kbCompiler kbdss kbDSupport kbVBp

Platform          : WINDOWS
Issue type        : kbbug

Last Reviewed: August 7, 1998