Set XEUS_CPP_OMP to -fopenmp (don't require openmp to be available to build time to set)

[mcbarton]

No description provided.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 73.51%. Comparing base (978c52c) to head (aeef2d6).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #475   +/-   ##
=======================================
  Coverage   73.51%   73.51%           
=======================================
  Files          23       23           
  Lines        1193     1193           
  Branches      111      111           
=======================================
  Hits          877      877           
  Misses        316      316           

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[vgvassilev]

LGTM! Do we have OMP tests in tree?

[mcbarton]

LGTM! Do we have OMP tests in tree?

We currently have a single test here

xeus-cpp/test/test_xcpp_kernel.py

Line 246 in 978c52c

class BaseXCppOpenMPTests(jupyter_kernel_test.KernelTests):

. It creates 2 threads, and gets them to output their thread number in descending order. It was added just to test basic openmp functionality. I will work on adding more tests in a future PR.