Description
Affects: JuliaCall
Describe the bug
Related to #219. There's currently a scenario with no possible workaround other than forcing a downstream user to set up environment variables to avoid a segfault.
Say that I import a package which uses serial Julia code. That package runs
from juliacall import Main as jlto start Julia.
Then, I import a different package. That package calls multithreaded Julia code, and thus to avoid a segfault (https://juliapy.github.io/PythonCall.jl/stable/faq/#Is-PythonCall/JuliaCall-thread-safe?) instead performs the import instead as:
import os
os.environ["PYTHON_JULIACALL_HANDLE_SIGNALS"] = "yes"
from juliacall import Main as jlHowever, at this point, the Julia runtime has already started. So now when I run a multithreaded portion of code, I will get a segfault, even though I implemented special workarounds in the multithreaded package.
How could I avoid this scenario? Indeed the user could always set up the environment variables themselves. But managing to figure this out from a random bus error will only be ~5% of users.