Move fstar assignment outside loop

[DanielDoehring]

See #3156 (comment)

[github-actions]

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[JoshuaLampert]

Wait...doesn't Threads.threadid() depend on the thread in the loop? Does this work?

[DanielDoehring]

Ah never mind, I forgot that there are some functions which are already being called from a threaded environment

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.96%. Comparing base (44f4289) to head (23ed8a3).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3205   +/-   ##
=======================================
  Coverage   96.96%   96.96%           
=======================================
  Files         673      673           
  Lines       52134    52134           
=======================================
  Hits        50547    50547           
  Misses       1587     1587           

Flag	Coverage Δ
unittests	96.96% <100.00%> (ø)

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