[Bug 47031] New: widl generates invalid typelib when an interface extends IAccessible

https://bugs.winehq.org/show_bug.cgi?id=47031

Bug ID: 47031
           Summary: widl generates invalid typelib when an interface
                    extends IAccessible
           Product: Wine
           Version: 4.5
          Hardware: x86
                OS: Linux
            Status: UNCONFIRMED
          Severity: major
          Priority: P2
         Component: tools
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Background:

We're attempting to add accessibility support to Firefox when building with the
mingw toolchain which requires implementing the IAccessibility2 interface.
However, the typelib (tlb) file that ends up getting generated is invalidated.
The generated tlb be partially loaded using oleview.exe but throws up several
TYPE_E_ELEMENTNOTFOUND  errors and the inherited interfaces are apparently not
defined. The interfaces with invalid/undefined inherited interfaces varies
depending on the order in which the child interfaces are defined in the source
IDL.

Reproduction:

I've created a min-repro here: https://github.com/pospeselr/mingw-widl-bug
(you'll need to update the Makefile to point to your local instance of widl)

I tested this with the latest mingw ( commit
c61763cc740f8f4986755eeafce832baa3655ee8 ) which uses widl version 4.5.

Links:

Mozilla bug tracking mingw accessibility issues:
https://bugzilla.mozilla.org/show_bug.cgi?id=1520177