Which version of the icl are you using?
The latest production release is: w_cproc_p_11.1.065
If you're using anything earlier, please try the latest. If still link error, please let us know.
when ipo is used the .obj contains an intermediate info that are not real .obj data. so link.exe from MSVC does not understand it.
but as long as you're building the program within MSVC, or using "xilink" to link, the program should link ok.
So there is a bug in the icl compiler.
Let's concentrate on the 1st error msg: "ipo_29285obj3.obj : error LNK2001: unresolved external symbol unwind.?updateRTT@RTO@RVProtocol@@QAEXABVTimeVal@EngineInfrastruct@@_N@Z.0.3".
the symbol: ?updateRTT@RTO@RVProtocol@@QAEXABVTimeVal@EngineInfrastruct@@_N@Z
is: public: void __thiscall RVProtocol::RTO::updateRTT(class EngineInfrastruct::TimeVal const &,bool)
so can you build only the .cpp containing above class implementation with /Qipo and others with no /Qipo? see if you still get the error.