Probably relevant, when running the test "py_NeurosurgicalPlanningTutorial", the following errors are reported:

// ---------------------------
Errors:

[...]
565: ERROR: In /home/jchris/Projects/Slicer-AHM-Superbuild-Release/VTK/Filtering/vtkDemandDrivenPipeline.cxx, line 727
565: vtkStreamingDemandDrivenPipeline (0x957b600): Input port 0 of algorithm vtkExtractSelectedPolyDataIds(0x957b370) has 0 connections but is not optional.
565:
565:
565: ERROR: In /home/jchris/Projects/Slicer-AHM/Libs/vtkTeem/vtkDiffusionTensorGlyph.cxx, line 222
565: vtkDiffusionTensorGlyph (0xcd1db10): No data to glyph!
[...]
// ---------------------------

Besides running "py_NeurosurigicalPlanningTutorial", the error messages in notes 0009874 can also be reproduced as below:
1) Start a Slicer Debug build.
2) Download Sample Data -> Download DTIVolume.
3) Go to 'Volumes' module and set DTIVolume as Active Volume.
4) Go to 'Diffusion Tensor Scalar Measurements' module, in IO panel, set DTIVolume as "Input DTI Volume".
5) 'Output Scalar Volume' -> Select 'Create a new volume'-> Click 'Apply'
6) 'Output Scalar Volume' -> Select 'Create a new volume'
The error messages will be shown in the console output.

The 'create a new volume' action triggers a vtkMRMLScene::NodeAddedEvent event. During processing this event, vtkMRMLModelDisplayableManager::GetActiveScalarName is called. In the fix of bug 0002392, to assign the field data, the GetActiveScalarName triggers an Update on the pipeline (modelDisplayNode->GetOutputPolyData()). But at this point, some required field data for algorithm vtkDiffusionTensorGlyph, such Tensors, hasn't been filled. So the glyph pipeline complains and throw the error messages described in notes 0009874.

It is fixed here: https://github.com/yuzhengZ/Slicer/commit/0bff039803d512313562ae1eda3cde40537052d4

In the fix of 0002392 (r21000 http://viewvc.slicer.org/viewvc.cgi/Slicer4?view=revision&revision=21000 ), the Update() on the polydata in vtkMRMLModelDisplayableManager::::GetActiveScalarName() is redundant. The Update() on the polydata in vtkMRMLModelNode::SetActivePointScalars has fixed 0002392. And the ideal fix for 0002392 is the solution 4 mentions in 0002392: vtkMRMLModelNode::SetActivePointScalars should use vtkAssignAttribute to be able to set the active scalar in the "VTK pipeline" rather than on the intermediate vtkPolyData pointdata.

A DTI volume related Slicer crash was reported and fixed in bug 0003380. The crash mentioned in bug 0003323 cannot be reproduced (Linux 64-bit build or Mac 64-bit build) after reverts r22363 ( http://viewvc.slicer.org/viewvc.cgi/Slicer4?view=revision&revision=22363 ). I am wondering if the fix of bug 0003380 also fixes this one. If not, please input more information on how to reproduce the crash.

@Julien: Could let me know what you think of that issue ?

Commit r23690 re-organize the pipeline to fix the glyphing. There is now only a warning displayed and no more crash.

See http://viewvc.slicer.org/viewvc.cgi/Slicer4?view=revision&revision=23690