Free the SSL context after unloading the provider libs

[dprandle]

Otherwise crashes on linux in dtor

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This is the fix for SSL context/provider destruction order

[ceztko]

It makes sense to me. Just a question: have you ever had a crash related to this?

[dprandle]

It makes sense to me. Just a question: have you ever had a crash related to this?

Yes - its how I found it.

It does not crash on Mac, but it does crash on Linux (Ubuntu 22.04.3 LTS) every time. My guess is the difference between the way the two OSs handle memory - it likely happens to work on Mac (and perhaps windows or other OSs).

[ceztko]

Ok, I asked because we have CI with tests on linux and it doesn't crash. Still, it makes sense to me to have resource disposal in the opposite order of creation, hence I don't need to see a reproduction with my eyes.

[dprandle]

This doesn't surprise me - those types of tests in my experience can only catch so much. We have several different SSL contexts being created and used by several different libraries, each of which utilize several threads. Its unlikely CL tests would catch the issues that may arise in this situation.