c++ – Cannot find function implementation in the code


In OpenVDB C++ repository, there is this condition inside VolumeToMesh.h:

if (ijk(0) > origin(0) && ijk(1) > origin(1) && ijk(2) > origin(2)) {
    constructPolygons(invertSurfaceOrientation,
        flags, refFlags, offsets, ijk, *signleafPt, *idxLeafPt, mesher); // 1st function: implementation not found
} else {
    constructPolygons(invertSurfaceOrientation,
        flags, refFlags, offsets, ijk, signAcc, idxAcc, mesher); // 2nd function: implementation is found
}

I see the implementation for the 2nd function at line #2512:

template<typename SignAccT, typename IdxAccT, typename PrimBuilder>
inline void
constructPolygons(
    bool invertSurfaceOrientation,
    Int16 flags,
    Int16 refFlags,
    const Vec3i& offsets,
    const Coord& ijk,
    const SignAccT& signAcc,
    const IdxAccT& idxAcc,
    PrimBuilder& mesher)
{
    // ...
}

However, the implementation for the 1st function is not found. To my surprise, in Visual Studio 2019 community edition, when I Ctrl-click on 1st function, VS editor navigates to line #2512 which implements 2nd function!

What am I missing?