Undefined OLE references in external library even when linking with libole32

Using MINGW, I'm trying to link my C code with a static C++ library that performs some OLE operations:

mingw32-gcc main.o resources.o -o mbcom.exe -L../../Lib/Iup -liup -liupole -lole32 -lcomctl32 -lstdc++ -mwindows

Unfortunately, I get this:

../../Lib/Iup/libiupole.a(tOleHandler.o):tOleHandler.cpp:(.text+0x341): undefined reference to `IID_IOleControl'
../../Lib/Iup/libiupole.a(tOleHandler.o):tOleHandler.cpp:(.text+0x9b0): undefined reference to `IID_IViewObject2'
../../Lib/Iup/libiupole.a(tOleHandler.o):tOleHandler.cpp:(.text+0xcb5): undefined reference to `IID_IUnknown'
../../Lib/Iup/libiupole.a(tOleHandler.o):tOleHandler.cpp:(.text+0xce8): undefined reference to `IID_IPersistStorage'
../../Lib/Iup/libiupole.a(tOleHandler.o):tOleHandler.cpp:(.text+0xd1b): undefined reference to `IID_IOleObject'
../../Lib/Iup/libiupole.a(tOleHandler.o):tOleHandler.cpp:(.text+0xd9d): undefined reference to `IID_IUnknown'
../../Lib/Iup/libiupole.a(tOleHandler.o):tOleHandler.cpp:(.text+0xdbf): undefined reference to `IID_IOleClientSite'
../../Lib/Iup/libiupole.a(tOleHandler.o):tOleHandler.cpp:(.text+0xde1): undefined reference开发者_运维问答 to `IID_IOleWindow'
../../Lib/Iup/libiupole.a(tOleHandler.o):tOleHandler.cpp:(.text+0xe03): undefined reference to `IID_IOleControlSite'
../../Lib/Iup/libiupole.a(tOleHandler.o):tOleHandler.cpp:(.text+0xe25): undefined reference to `IID_IDispatch'
../../Lib/Iup/libiupole.a(tOleHandler.o):tOleHandler.cpp:(.text+0xe51): undefined reference to `IID_IOleInPlaceSite'
../../Lib/Iup/libiupole.a(tOleHandler.o):tOleHandler.cpp:(.text+0x1129): undefined reference to `GUID_NULL'
../../Lib/Iup/libiupole.a(tOleHandler.o):tOleHandler.cpp:(.text+0x124d): undefined reference to `GUID_NULL'
../../Lib/Iup/libiupole.a(tOleInPlaceSite.o):tOleInPlaceSite.cpp:(.text+0xc8): undefined reference to `IID_IOleInPlaceObject'
../../Lib/Iup/libiupole.a(tDispatch.o):tDispatch.cpp:(.text+0x108): undefined reference to `GUID_NULL'
../../Lib/Iup/libiupole.a(tDispatch.o):tDispatch.cpp:(.text+0x137): undefined reference to `VariantInit@4'
../../Lib/Iup/libiupole.a(tOleInPlaceFrame.o):tOleInPlaceFrame.cpp:(.text+0x1d9): undefined reference to `IID_IUnknown'
../../Lib/Iup/libiupole.a(tOleInPlaceFrame.o):tOleInPlaceFrame.cpp:(.text+0x211): undefined reference to `IID_IOleInPlaceUIWindow'
../../Lib/Iup/libiupole.a(tOleInPlaceFrame.o):tOleInPlaceFrame.cpp:(.text+0x22b): undefined reference to `IID_IOleWindow'
../../Lib/Iup/libiupole.a(tOleInPlaceFrame.o):tOleInPlaceFrame.cpp:(.text+0x245): undefined reference to `IID_IOleInPlaceFrame'
collect2: ld returned 1 exit status
mingw32-make: *** [mbcom.exe] Error 1

The only solution I can find is to link with libole32, but as you can see, I'm already doing that.

Any other ideas?

---

libuuid is where these things should be found.

Except VariantInit, which is in liboleaut32.