The _socket extension uses _PyCapsule_SetTraverse() to visit and clear
the socket type in the garbage collector. So the _socket.socket type
can be cleared in some corner cases when it wasn't possible before.
Replace PyDict_GetItemWithError() with PyDict_GetItemRef() which
returns a strong reference.
Cleanup also the function: move variable definition to their first
assignation, rename variable names to use name longer than 1
character.
Replace _PyDict_GetItemStringWithError() calls with
PyDict_GetItemStringRef() which returns a strong reference to the
item.
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
Remove private _PyDict_GetItemStringWithError() function of the
public C API: the new PyDict_GetItemStringRef() can be used instead.
* Move private _PyDict_GetItemStringWithError() to the internal C API.
* _testcapi get_code_extra_index() uses PyDict_GetItemStringRef().
Avoid using private functions in _testcapi which tests the public C
API.
This finishes the work begun in gh-107760. When, while projecting a superblock, we encounter a call to a short, simple function, the superblock will now enter the function using `_PUSH_FRAME`, continue through it, and leave it using `_POP_FRAME`, and then continue through the original code. Multiple frame pushes and pops are even possible. It is also possible to stop appending to the superblock in the middle of a called function, when running out of space or encountering an unsupported bytecode.
The linked list of objects was a global variable, which broke isolation between interpreters, causing crashes. To solve this, we've moved the linked list to each interpreter.
It was possible for the trashcan to delay the deallocation of a
PyFrameObject until after its corresponding _PyInterpreterFrame has
already been freed. So frame_dealloc needs to avoid dereferencing the
f_frame pointer unless it first checks that the pointer still points
to the interpreter frame within the frame object.
Signed-off-by: Anders Kaseorg <andersk@mit.edu>
The _xxsubinterpreters module should not rely on internal API. Some of the functions it uses were recently moved there however. Here we move them back (and expose them properly).
We tried this before with a dict and for all interned strings. That ran into problems due to interpreter isolation. However, exclusively using a per-interpreter cache caused some inconsistency that can eliminate the benefit of interning. Here we circle back to using a global cache, but only for statically allocated strings. We also use a more-basic _Py_hashtable_t for that global cache instead of a dict.
Ideally we would only have the global cache, but the optional isolation of each interpreter's allocator means that a non-static string object must not outlive its interpreter. Thus we would have to store a copy of each such interned string in the global cache, tied to the main interpreter.
Move private _PyDict functions to the internal C API (pycore_dict.h):
* _PyDict_Contains_KnownHash()
* _PyDict_DebugMallocStats()
* _PyDict_DelItemIf()
* _PyDict_GetItemWithError()
* _PyDict_HasOnlyStringKeys()
* _PyDict_MaybeUntrack()
* _PyDict_MergeEx()
No longer export these functions.
Move private debug _PyObject functions to the internal C API
(pycore_object.h):
* _PyDebugAllocatorStats()
* _PyObject_CheckConsistency()
* _PyObject_DebugTypeStats()
* _PyObject_IsFreed()
No longer export most of these functions, except of
_PyObject_IsFreed().
Move test functions using _PyObject_IsFreed() from _testcapi to
_testinternalcapi. check_pyobject_is_freed() test no longer catch
_testcapi.error: the tested function cannot raise _testcapi.error.
Move the private _PyInterpreterID C API to the internal C API: add a
new pycore_interp_id.h header file.
Remove Include/interpreteridobject.h and
Include/cpython/interpreteridobject.h header files.
* Add PyDict_GetItemRef() and PyDict_GetItemStringRef() functions.
Add these functions to the stable ABI version 3.13.
* Add unit tests on the PyDict C API in test_capi.
There was a slight race in _Py_ClearFileSystemEncoding() (when called from _Py_SetFileSystemEncoding()), between freeing the value and setting the variable to NULL, which occasionally caused crashes when multiple isolated interpreters were used. (Notably, I saw at least 10 different, seemingly unrelated spooky-action-at-a-distance, ways this crashed. Yay, free threading!) We avoid the problem by only setting the global variables with the main interpreter (i.e. runtime init).
A static (process-global) str object must only have its "interned" state cleared when no longer interned in any interpreters. They are the only ones that can be shared by interpreters so we don't have to worry about any other str objects.
We trigger clearing the state with the main interpreter, since no other interpreters may exist at that point and _PyUnicode_ClearInterned() is only called during interpreter finalization.
We do not address here the fact that a string will only be interned in the first interpreter that interns it. In any subsequent interpreters str.state.interned is already set so _PyUnicode_InternInPlace() will skip it. That needs to be addressed separately from fixing the crasher.
Guido van Rossum
Victor Stinner
Irit Katriel
Dong-hee Na
Mark Shannon
Martin DeMello
Joon Hwan 김준환
Nikita Sobolev
Serhiy Storchaka
Marc Mueller
Brandt Bucher
Eric Snow
Anders Kaseorg
Illia Volochii
James Hilton-Balfe
Dennis Sweeney
Jelle Zijlstra