[issue30876] SystemError on import

Brett Cannon added the comment: So this is very old semantics from the Python 2 days. I think Nick's idea of transforming the import to `import pkg.mod` when pkg isn't in sys.modules is probably the simplest, cleanest solution if we're going to change this. --

[issue30876] SystemError on import

Antoine Pitrou added the comment: I concur with Serhiy: SystemError is a smell that C code isn't taking appropriate precautions before dealing with user code or data. -- nosy: +pitrou ___ Python tracker

[issue30876] SystemError on import

Nick Coghlan added the comment: If there are intermittent concurrent problems associated with this behaviour, I think that may be a sign that the current management of the per-module import locks is inadequate, since it isn't adequately accounting for direct manipulation of sys.modules in

[issue30876] SystemError on import

Serhiy Storchaka added the comment: I don't know other way to provoke SystemError by Python code. Always if SystemError was leaked this considered a bug and was fixed. When unload package you need to remove its name and names of its submodules from sys.modules. This is a common case. If the

[issue30876] SystemError on import

Nick Coghlan added the comment: To summarise what the attached source archive is doing, module1.py is essentially: import sys del sys.modules(__package__) from . import module2 So the only way to trigger this is by corrupting the import state, which seems like an appropriate use

[issue30876] SystemError on import

Nick Coghlan added the comment: I don't think we're that strict with SystemError - once folks are messing about with deleting things from the sys module, they *are* writing their own system level code, and may end up provoking SystemError if they corrupt the interpreter state in the process.

[issue30876] SystemError on import

New submission from Serhiy Storchaka: It is possible to get SystemError on import (see attached archive). $ ./python -c 'import package.module1' Traceback (most recent call last): File "", line 1, in File "/home/serhiy/py/cpython/package/module1.py", line 3, in from . import module2