We should maintain the invariant that a zero `ob_tid` implies the
refcount fields are merged.
* Move the assignment in `_Py_MergeZeroLocalRefcount` to immediately
before the refcount merge.
* Update `_PyTrash_thread_destroy_chain` to set `ob_ref_shared` to
`_Py_REF_MERGED` when setting `ob_tid` to zero.
Also check this invariant with assertions in the GC in debug builds.
That uncovered a bug when running out of memory during GC.
Any cross-interpreter mechanism for passing objects between interpreters must be very careful to respect isolation, even when the object is effectively immutable (e.g. int, str). Here this especially relates to when an interpreter sends one of its objects, and then is destroyed while the inter-interpreter machinery (e.g. queue) still holds a reference to the object.
When I added interpreters.Queue, I dealt with that case (using an atexit hook) by silently removing all items from the queue that were added by the finalizing interpreter.
Later, while working on concurrent.futures.InterpreterPoolExecutor (gh-116430), I noticed it was somewhat surprising when items were silently removed from the queue when the originating interpreter was destroyed. (See my comment on that PR.)
It took me a little while to realize what was going on. I expect that users, which much less context than I have, would experience the same pain.
My approach, here, to improving the situation is to give users three options:
1. return a singleton (interpreters.queues.UNBOUND) from Queue.get() in place of each removed item
2. raise an exception (interpreters.queues.ItemInterpreterDestroyed) from Queue.get() in place of each removed item
3. existing behavior: silently remove each item (i.e. Queue.get() skips each one)
The default will now be (1), but users can still explicitly opt in any of them, including to the silent removal behavior.
The behavior for each item may be set with the corresponding Queue.put() call. and a queue-wide default may be set when the queue is created. (This is the same as I did for "synconly".)
They are alternate constructors which only accept numbers
(including objects with special methods __float__, __complex__
and __index__), but not strings.
It is our general practice to make new optional parameters keyword-only,
even if the existing parameters are all positional-or-keyword. Passing
this parameter as positional would look confusing and could be error-prone
if additional parameters are added in the future.
Performance improvement to `float.fromhex`: use a lookup table
for computing the hexadecimal value of a character, in place of the
previous switch-case construct. Patch by Bruno Lima.
* The result has type Py_ssize_t, not intptr_t.
* Type cast between unsigned and signdet integer types should be explicit.
* Downcasting should be explicit.
* Fix integer overflow check in sum().
On POSIX systems, excluding macOS framework installs, the lib directory
for the free-threaded build now includes a "t" suffix to avoid conflicts
with a co-located default build installation.
When builtin static types are initialized for a subinterpreter, various "tp" slots have already been inherited (for the main interpreter). This was interfering with the logic in add_operators() (in Objects/typeobject.c), causing a wrapper to get created when it shouldn't. This change fixes that by preserving the original data from the static type struct and checking that.
This makes select.poll() and kqueue() objects thread-safe in the
free-threaded build. Note that calling close() concurrently with other
functions is still not thread-safe due to races on file descriptors
(gh-121544).
Tian Gao
Sam Gross
Milan Oberkirch
Sergey B Kirpichev
Eric Snow
Ken Jin
Rodrigo Girão Serrão
Sebastian Rittau
Serhiy Storchaka
Dominic H
Kumar Aditya
Jelle Zijlstra
Sviatoslav Sydorenko (Святослав Сидоренко)
Samuel Thibault
sobolevn
Hood Chatham
Bruno Lima
Jan Musílek
Tomas R
Victor Stinner
Ulrik Södergren
Gregor
Bénédikt Tran
mirelagrigoras
Timon Viola
Pablo Galindo Salgado
Marta Gómez Macías
Bas Bloemsaat
Zachary Ware
Savannah Ostrowski