[split]The reason GCC doesn't work for us

[DCoder]

I'm afraid that doesn't help:

D:\bin\gcc3\bin>mingw32-g++ a.cpp -fdump-class-hierarchy --save-temps -DWIN32 -D_WINDOWS -DUNICODE -D_REFGUID_DEFINED
a.cpp:4: warning: 'com_interface' is obsolete; g++ vtables are now COM-compatible by default

D:\bin\gcc4\bin>mingw32-g++ a.cpp -fdump-class-hierarchy --save-temps -DWIN32 -D_WINDOWS -DUNICODE -D_REFGUID_DEFINED
a.cpp:4: warning: 'com_interface' is obsolete; g++ vtables are now COM-compatible by default

The produced code is completely identical to the old version, and gcc documentation says:
/*
__attribute__((com_interface)) is obsolete in __GNUC__ >= 3
g++ vtables are now COM-compatible by default
*/

Thanks for your efforts, though