[vtk-developers] vtk-8.2.0-rc2 problem building wheels

[Ben Boeckel]

On Tue, Nov 27, 2018 at 19:02:14 -0500, Jean-Christophe Fillion-Robin wrote:
> > Should I just ignore the libvtkPythonInterpreter and leave the
> > PYTHON_LIBRARY field blank?

It being blank will cause `find_library` to try and find it itself. I
think the error is that now an empty linker script is not valid, but I'm
not sure. Is it possible to use an older compiler/linker to make the
wheels?

> It looks like introducing an option to conditionally build
> vtkPythonInterpreter would address the issue here.
> 
> @Ben: What do you think ?

How would this work? If it is disabled, `vtkWrappingPythonCore` (a
dependency of all wrapped Python modules) and `vtkRenderingMatplotlib`
can't be built.

For the record, the new module system's way of doing this is here:

    https://gitlab.kitware.com/ben.boeckel/vtk/blob/new-cmake-module/Utilities/Python/CMakeLists.txt#L118

Basically, the `VTK::Python` module contains the library for
executables, but is just the magic flags to ignore the missing symbols
when linking libraries. So, it should "just work", but it does require
3.13+ for `target_link_options` (without it, direct linking is used). It
can't really be backported because the old module system is quite
allergic to CMake's target stuff (since it was designed basically as the
same thing, but predate's CMake's logic).

--Ben