Since Slicer commit 997de030a6cd340b9f389c5bf54e8cacb55ddced, SlicerMarkupsToModel fails to build on Linux with missing curveGenerator->SetInputPoints and curveGenerator->GetOutputPoints. These are indeed discarded in this commit.
FYI.
Hopefully, SlicerMarkupsToModel update may follow.
Thanks for reporting this. We have made the curve generator a real VTK filter and it seems that we were not careful enough to keep the API fully backward compatible. We’ll fix this soon. @Sunderlandkyl can you have a look?