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Linkage problem with class in a cluster

This problem is illustrated at 1:30 of this video.


If the output of a VI is a cluster containing a class, a linking problem occurs.


I tried to reproduce the problem in the simplest way. I uploaded 3 files (LabVIEW 2016 format) with this post:


Class 1.lvclass




So Class 1 is simply an empty class.

"Output" creates a cluster containing Class 1 and outputs it as an indicator.


"Use" uses the output of "Output".


So, if you open any of the two VIs, no problem.


If you import "Output" in a blank VI that is not in a project, the VI breaks. The reported error is blank. As shown in the video, you can create a project, add the calling VI to the project when prompted, then create a cluster constant, and the problem is fixed. You can also close the VI, reopen it, force a re-compile and it should be fixed. A simple force recompile does not work.


If you import "Output" into a blank VI that is already part of a project, the calling VI breaks and the only way I found to fix it is close the project and reopen it.


I reproduced the problem with LabVIEW 2016, 2017, and 2018.


Am I the only one having that problem? Is there a simpler way to fix the linkage? Is there a way to permanently fix the linkage in "Output"?


Any information about that problem would be appreciated.


Marc Dubois
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I'd say most VIs are created in a project nowadays. So either nobody noticed it, or if they did created a project and let it go...

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Using a project helps but until you save and reopen the project (and possibly force a recompile), the calling VI is broken and the block diagram looks like this:



Marc Dubois
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