It looks like RTIfedTime.cc defines methods whose declaration include `throw` of RTI::Exception types. Therefore, linker is looking for the typeinfo (as I read in https://gcc.gnu.org/wiki/Visibility) and doesn't find it as the RTI-> FedTime dependency is not explicitely made in the CMake file (I understood this was made on purpose to avoid a circular dependency).

As explained here (https://gcc.gnu.org/onlinedocs/gcc/Vague-Linkage.html), in GCC, the typeinfo object (for polymorphic classes) is written in the translation unit of the definition of the first non-inline virtual method. (which is the RTI::Exception destructor in this case (baseTypes.hh/line 31: virtual ~Exception();)

Since the definition of RTI::Exception destructor is in RTITypes.cc, I assume typeinfo objects are only in libRTI.so.

So we need to force the compiler to transfer the RTI::Exception typeinfo to libFedTime (if you want to keep those signatures as such).

2-character solution
Make RTI::Exception destructor purely virtual (This way, there is no non-inline virtual function and so GCC seems to copy the typeinfo object to libFedTime - as it does not assume it must be somewhere else -)

2-line solution
Copy the destructor definition to RTIfedTime.cc
RTI::Exception::~Exception()
{
    if (NULL!=_reason) {
        free(_reason);
    }
}

I tested with GCC only, they both work.

Attached are the two possible patchs I came up with.