DOCUMENT:Q196830 11-FEB-2002 [visualc] TITLE :FIX: MIDL2039 Warning with IFontDisp/IPictureDisp Parameter Type PRODUCT :Microsoft C Compiler PROD/VER::2.1,3.0,5.0,6.0 OPER/SYS: KEYWORDS:kberrmsg kbActiveX kbATL210bug kbAutomation kbVC500bug kbVC600bug kbATL300bug MSGRAPH k ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - The Microsoft Active Template Library (ATL), versions 2.1, 3.0, used with: - Microsoft Visual C++, 32-bit Enterprise Edition, versions 5.0, 6.0 - Microsoft Visual C++, 32-bit Professional Edition, versions 5.0, 6.0 - Microsoft Visual C++, 32-bit Learning Edition, version 6.0 ------------------------------------------------------------------------------- SYMPTOMS ======== When you compile an .idl file with IFontDisp or IPictureDisp as parameters of methods in Visual C++ 5.0 or Visual C++ 6.0, you get a MIDL2039 warning. CAUSE ===== This is due to a bug in Ocidl.idl source. You must add the dual attribute to the interface declarations for IFontDisp and IPictureDisp. RESOLUTION ========== To prevent the warning, add the dual attribute to the IFontDisp and IPictureDisp interface declarations in Ocidl.idl, as in the following example: [ object, dual, uuid(BEF6E003-A874-101A-8BBA-00AA00300CAB), pointer_default(unique) ] interface IFontDisp : IDispatch { typedef IFontDisp * LPFONTDISP; } [ object, dual, uuid(7BF80981-BF32-101A-8BBB-00AA00300CAB), pointer_default(unique) ] interface IPictureDisp : IDispatch { typedef IPictureDisp * LPPICTUREDISP; } STATUS ====== Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. This problem was corrected in Microsoft Visual C++ .NET. MORE INFORMATION ================ Steps to Reproduce Behavior --------------------------- 1. Create a new ATL COM AppWizard Project with DLL as the Server Type. 2. Insert a new ATL Control using the ATL Object Wizard, and add the Font stock property by selecting it from the Stock Properties tab of the wizard. 3. Build the .idl file generated by the wizard. You should receive the following warnings: warning MIDL2039 : interface does not conform to [oleautomation] attribute warning MIDL2039 : interface does not conform to [oleautomation] attribute warning MIDL2039 : interface does not conform to [oleautomation] attribute Additional query words: ====================================================================== Keywords : kberrmsg kbActiveX kbATL210bug kbAutomation kbVC500bug kbVC600bug kbATL300bug MSGRAPH kbGrpDSMFCATL kbIDL kbNoUpdate Technology : kbVCsearch kbAudDeveloper kbATLsearch Version : :2.1,3.0,5.0,6.0 Issue type : kbbug Solution Type : kbfix ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2002.