Slicer builds nicely with VTK9 on Arch Linux with gcc 10.2.
MarkupsToModel fails to build on VTK_OVERRIDE and VTK_DELETE_FUNCTION. If all occurrences of these macros are removed, the build process completes. Can’t know if it’s the right fix.
I removed these macros in 3 header files. It was not a replacement by some other non-empty values. In particular, there is no VTK version testing. I can send the pull request as such, and just want to confirm that it’s what you expect.