I’ve built Slicer and then SlicerRT from source several times in the past. I followed the online instructions. In the same computer, I recently updated (via git pull) the Slicer and SlicerRT repositories to master, and then rebuilt from scratch. The build of Slicer works fine, and I can start Slic…

I just checked quickly and it seems they changed the value of TypeDisplayName from char* to std::string, may be related.

Hmm could be also that before it was ‘inline’ in the header, and now it’s in the source file? So missing linking to the library?

It might also be some cache issue, I will try wiping out the build dir and rebuilding from scratch.

A full rebuild solved this linker error. I do still get the runtime crash concerning the MockPythonDoseEngine

Alright, with this diff: diff --git a/ExternalBeamPlanning/Widgets/Python/CMakeLists.txt b/ExternalBeamPlanning/Widgets/Python/CMakeLists.txt index 5ce02b92..e4603d84 100644 --- a/ExternalBeamPlanning/Widgets/Python/CMakeLists.txt +++ b/ExternalBeamPlanning/Widgets/Python/CMakeLists.txt @@ -7,7 +7,…

Thank you very much Fernando! Did you do anything other than commenting out the mock engine to fix the crash? Just to know exactly what worked in the end, because it seems strange that a tbb related crash is resolved by excluding a python script.

You are welcome. I did nothing else. In my case, I did not get any warning about tbb when running gdb. Maybe, that was an artefact related to the fact that the Slicer tbb: tbb-install/lib/intel64/gcc4.8/libtbb_debug.so.12 does not play well with a system onetbb installed. I do not have onetbb in…

Excluding the mock python engine fixes the crash for me as well. I don’t understand the reason though. I also don’t know why the orthovoltage engine is not loading, but it has not been maintained, and requires some special tools being installed and configured locally, so I am pretty sure nobody uses…

Sounds good to me! Thanks for checking.

Change pushed, see BUG: Exclude MockPythonDoseEngine to fix crash on startup · SlicerRt/SlicerRT@8088306 · GitHub

SlicerRT built from source cannot start

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cpinter (Csaba Pinter) August 7, 2025, 9:28am 36

Interesting. Thanks for further looking into it. Could this be related to the Python upgrade? The same thing that causes this problem. @lassoan @jcfr

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SlicerRT built from source cannot start

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