GeezerVison

@Fidget-Spinner who the issue is currently assigned to has helped me with this PR.

@devdanzin can we use your repro as a test case please?

Sure, in this case and any others, whenever you want.

@caje731 please add a test case to Lib/test/test_capi/test_opt.py by copying the script from here #141786 (comment). You can take a look at test_interpreter_finalization_with_generator_alive to see how to run a test in a subprocess easily.

I should note that the following simple diff in the test:

diff --git a/Lib/test/test_capi/test_opt.py b/Lib/test/test_capi/test_opt.py
index 0f67f19a115..9027be79254 100644
--- a/Lib/test/test_capi/test_opt.py
+++ b/Lib/test/test_capi/test_opt.py
@@ -2772,7 +2772,7 @@ def B(B):
                if rand.random() < 0.1:
                    C(B)

-            for D in range(200):
+            for D in range(350):
                try:
                    B(D)
                except:

produces a breakage in the test:

...
stderr:
---
Traceback (most recent call last):
  File "<string>", line 136, in <module>
    b()
    ~^^
  File "<string>", line 101, in b
    del B
        ^
UnboundLocalError: cannot access local variable 'B' where it is not associated with a value
---

At this point I'm unsure if this is related to JIT optimizations, but superficially seems to be just a side-effect of the symbol-conflicts (ab)used in the test.

@markshannon i would like to merge this still. Even with your proposed fix it's possible to invalidate an executor while tracing. This is a separate issue.