Ok, this is a duplicate of this one from June last year (macOS 10.15.5):
Cause and solution completely unknown, all debugging attempts failed.
What i would recommend is for your studen to upgrade to the latest macOS 10.15.7 with all Apple updates, then retry. That’s what i’m running on my test machine with R2020b and no known problems, and this is definitely a macOS operating system bug, also reported by other users on forums on the internet, of other software completely unrelated to neuroscience. Nothing we could really do about it. The tell-tale is if you see the abort() detected in the stacktrace, and this snippet:
`` [ 20] 0x00007fff6b61fd8a /usr/lib/system/libdyld.dylib+00023946 dlopen+00000171
[ 21] 0x0000000190a5d3d3 /Applications/Psychtoolbox/PsychBasic/Screen.mexmaci64+00811987 PsychLoadTextRendererPlugin+00000339``
Ie. a call to dlopen(), and before that, a call to PsychLoadTextRendererPlugin.
All crashes you see with this stack trace are the same unfixable root cause - a macOS bug.
Two other potential workarounds:
-
As explained in
help DrawTextPlugin, rename or delete/Applications/MATLAB_R2020b.app/bin/maci64/libfreetype.6.dylib. Restart Matlab. Unlikely to help, but who knows? -
If text rendering quality/exact text formatting is not important, as i understand this is just for a basic teaching course, not actual data collection, you could also ignore the DownloadPsychtoolbox crash as all important setup steps have completed at time of the crash. PTB should be fully functional apart from the high quality text renderer, which crashes:
delete([PsychtoolboxRoot 'PsychBasic/PsychPlugins/libptbdrawtext_ftgl64.dylib'])
If the plugin is deleted, it can’t be loaded and the load can’t fail with a Matlab crash. Screen() will print some warning message each time a script tries to draw text, and fall back to the old legacy Apple text renderer, which is slower, lower quality, inconsistent in its text layout wrt. the normal case, but probably good enough for pure teaching purposes.
Work time used up on this license: 42 minutes. 18 minutes left for further support incidents.
-mario