Compile Error: Definition Provided for Explicit instantiation

When compiling software that includes vtkFloatArray.h with Qtcreator and gcc 9.3 as compiler on Ubuntu 20.04 I receive the following error:

/usr/local/include/vtk-8.2/vtkFloatArray.h:38:3: error: definition provided for explicit instantiation
   38 |   vtkTypeMacro(vtkFloatArray, vtkDataArray)
      |   ^~~~~~~~~~~~

The code highlighted is:

class VTKCOMMONCORE_EXPORT vtkFloatArray : public vtkDataArray
{ 
public:
  vtkTypeMacro(vtkFloatArray, vtkDataArray)

I also tried to compile this code on Windows with VisualStudio 2019 I didn’t receive this error.

Does somebody kindly have any idea what this error means?

@RobertMaynard @AllisonVacanti @allison.vacanti (not sure which one is the active account)

The master version of VTK builds ok with no errors with gcc 9.3 on Ubuntu 20.04. So this is most likely a vtk-8.2 issue.

Thank you for the confirmation, @Andrew. I will thus investigate a bit more and see whether there might be some setting on my system that cause the problem.

Thank you again @Andrew for your help. I realized this was a problem on my system. Thanks for your help and for checking.

Glad to help. I’m pleased you solved it.