Attempting a rebuild of vtk-dicom (using gcc 15.3.0 with vtk 9.6) got this build
error:

[ 54%] Generating Python wrapper sources for vtkDICOMWriter
/usr/bin/vtkWrapPython-9.6 -MF //build/vtk-dicom-0.8.17/obj-x86_64-linux-gnu/CMakeFiles/vtkDICOMPython/vtkDICOMWriterPython.cxx.d @/build/vtk-dicom-0.8.17/obj-x86_64
-linux-gnu/CMakeFiles/vtkDICOMPython/vtkDICOM-python.None.args -o /build/vtk-dicom-0.8.17/obj-x86_64-linux-gnu/CMakeFiles/vtkDICOMPython/vtkDICOMWriterPython.cxx /b
uild/vtk-dicom-0.8.17/Source/vtkDICOMWriter.h
/usr/bin/vtkWrapPython-9.6 -MF /build/vtk-dicom-0.8.17/obj-x86_64-linux-gnu/CMakeFiles/vtkDICOMPython/vtkDICOMVRPython.cxx.d @/build/vtk-dicom-0.8.17/obj-x86_64-lin
ux-gnu/CMakeFiles/vtkDICOMPython/vtkDICOM-python.None.args -o /build/vtk-dicom-0.8.17/obj-x86_64-linux-gnu/CMakeFiles/vtkDICOMPython/vtkDICOMVRPython.cxx /build/vtk
-dicom-0.8.17/Source/vtkDICOMVR.h
/build/vtk-dicom-0.8.17/DicomCli/progress.cxx: In member function ‘virtual void ProgressObserver::Execute(vtkObject*, long unsigned int, void*)’:
/build/vtk-dicom-0.8.17/DicomCli/progress.cxx:40:14: error: ‘cout’ is not a member of ‘std’
   40 |         std::cout << "\r                                   ";
      |              ^~~~
/build/vtk-dicom-0.8.17/DicomCli/progress.cxx:18:1: note: ‘std::cout’ is defined in header ‘<iostream>’; this is probably fixable by adding ‘#include <iostream>’
   17 | #include "vtkDICOMUtilities.h"
  +++ |+#include <iostream>
   18 |


Evidently gcc 15.3 has tightened up C++ conditions (-std=gnu++17 is
now default), so the code now needs an explicit #include <iostream>

Incidently the std::cout errors reported here are triggered by vtk 9.6.
Previously vtk had been including the headers and declaring use of std::cout etc.
It stoppe doing that in MR#11993
https://gitlab.kitware.com/vtk/vtk/-/merge_requests/11993

So this bug had been present earlier, but was hidden by
previous versions of vtk.

Files which are using std:: objects must #include their respective headers.

Dear maintainer,

I've prepared an NMU for vtk-dicom (versioned as 0.8.17-2.1) and
uploaded it to DELAYED/2. Please feel free to tell me if I should
cancel it.

cu
Adrian

Hello,

Bug #1140906 in vtk-dicom reported by you has been fixed in the
Git repository and is awaiting an upload. You can see the commit
message below and you can check the diff of the fix at:

https://salsa.debian.org/med-team/vtk-dicom/-/commit/e01e4b0b997925ee19cdef393d7d15d525dee108

(this message was generated automatically)
-- 
Greetings

https://bugs.debian.org/1140906

We believe that the bug you reported is fixed in the latest version of
vtk-dicom, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1140906@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Santiago Vila <sanvila@debian.org> (supplier of updated vtk-dicom package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Fri, 17 Jul 2026 18:45:00 +0200
Source: vtk-dicom
Architecture: source
Version: 0.8.17-3
Distribution: unstable
Urgency: medium
Maintainer: Debian Med Packaging Team <debian-med-packaging@lists.alioth.debian.org>
Changed-By: Santiago Vila <sanvila@debian.org>
Closes: 1140906
Changes:
 vtk-dicom (0.8.17-3) unstable; urgency=medium
 .
   * Team upload.
 .
   [ Adrian Bunk ]
   * Fix FTBFS with VTK 9.6. Closes: #1140906.
 .
   [ Santiago Vila ]
   * Drop "Priority: optional" (default).
   * Update standards-version.
   * Add debian/salsa-ci.yml.
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