Encountered an issue with PowerPoint add-in integration. Reviewing the logs revealed the problem was due to the lack of CLSID lookup via the CurVer section and incorrect handling of the PARAMFLAG_NONE flag. A test was conducted in Windows to verify the handling of PARAMFLAG_NONE, PARAMFLAG_FIN, and PARAMFLAG_FOUT. Test class: ``` interface ITest : IDispatch { [id(1)] HRESULT TestMethod(BSTR* value); [id(2)] HRESULT TestMethodOut([out] BSTR* retVal); [id(3)] HRESULT TestMethodIn([in] BSTR* inVal); }; ``` Results in Windows: ``` --------TestMethod-------- Variant type: 0x0008 (VT_BSTR) [CTest::TestMethod] Hello from VT_BSTR Invoke returned: 0x00000000 -------TestMethodIn------- Variant type: 0x0008 (VT_BSTR) [CTest::TestMethodIn] Hello from VT_BSTR Invoke returned: 0x00000000 -------TestMethodOut------- Variant type: 0x0008 (VT_BSTR) [CTest::TestMethodOut] (null) Invoke returned: 0x00000000 ``` Results in Wine: ``` --------TestMethod-------- Variant type: 0x0008 (VT_BSTR) [CTest::TestMethod] (null) Invoke returned: 0x00000000 -------TestMethodIn------- Variant type: 0x0008 (VT_BSTR) [CTest::TestMethodIn] Hello from VT_BSTR Invoke returned: 0x00000000 -------TestMethodOut------- Variant type: 0x0008 (VT_BSTR) [CTest::TestMethodOut] (null) ``` Therefore, parameters with the PARAMFLAG_NONE flag are implied to be input parameters in Windows and are handled accordingly as PARAMFLAG_FIN. Added tests for the implemented changes. In the last two tests (their code is provided below), the CLSID is nullified in the guid_from_string function, which is why this test is left with a todo_wine tag. ``` clsid = CLSID_StdFont; hr = CLSIDFromString(L"MyApp.DocumentTest.3", &clsid); todo_wine ok(IsEqualCLSID(&clsid, &CLSID_StdFont), "Unexpected clsid %s.\n", wine_dbgstr_guid(&clsid)); clsid = CLSID_StdFont; hr = CLSIDFromString(L"MyApp.DocumentTest.5", &clsid); todo_wine ok(IsEqualCLSID(&clsid, &CLSID_StdFont), "Unexpected clsid %s.\n", wine_dbgstr_guid(&clsid)); ``` -- v5: combase: Implement CLSID lookup with CurVer fallback oleaut32: Fix parameter value loss in ITypeInfo_Invoke for byref parameters https://gitlab.winehq.org/wine/wine/-/merge_requests/9639