• Fails only with numpy and py::array_t and "single" py::scoped_interpreter
  (~> branch main)
• Does not fail, when having only single py::scoped_interpreter
  (~> branch works_when_having_only_single_scoped_interpreter -> see diff): why?
• Does not fail, when changing to py::list
  (~> branch works_when_removing_numpy -> see diff): why?

mkdir build/
cd    build/
cmake ..              # will clone https://github.com/pybind/pybind11.git (stable)
cmake --build . -j    # will also copy mysum.py into the build/ directory
./go                  # run (need a python with numpy)

The result is:

Sum is: 15
double free or corruption (out)
Aborted (core dumped)

It fails in this line, but only the 2nd time through the loop!!!

So if I simply change the following line
constexpr int NUM_LOOPS = 2;
to this
constexpr int NUM_LOOPS = 1;
then it will not fail.

Why does it fail with NUM_LOOPS = 2?
How can one fix it?

Thanks