Make `warnings.catch_warnings()` use a context variable for holding
the warning filtering state if the `sys.flags.context_aware_warnings`
flag is set to true. This makes using the context manager thread-safe in
multi-threaded programs.
Add the `sys.flags.thread_inherit_context` flag. If true, starting a new
thread with `threading.Thread` will use a copy of the context
from the caller of `Thread.start()`.
Both these flags are set to true by default for the free-threaded build
and false for the default build.
Move the Python implementation of warnings.py into _py_warnings.py.
Make _contextvars a builtin module.
Co-authored-by: Kumar Aditya <kumaraditya@python.org>
* Remove getopt and optparse deprecation notices
* Add new docs sections for command line app helper libraries
* Add guidance on choosing a CLI parsing library to the optparse docs
* Link to the new guidance from the argparse and getopt docs
* Reword intro in docs section for superseded stdlib modules
* Reframe the optparse->argparse guide as a migration guide
rather than as an upgrade guide
---------
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
* Replace uses of `PyCell_GET` and `PyCell_SET`. These macros are not
safe to use in the free-threaded build. Use `PyCell_GetRef()` and
`PyCell_SetTakeRef()` instead.
* Since `PyCell_GetRef()` returns a strong rather than borrowed ref, some
code restructuring was required, e.g. `frame_get_var()` returns a strong
ref now.
* Add critical sections to `PyCell_GET` and `PyCell_SET`.
* Move critical_section.h earlier in the Python.h file.
* Add `PyCell_GET` to the free-threading howto table of APIs that return
borrowed refs.
* Add additional unit tests for free-threading.
Docs: Remove the logging howto potential promise of multiprocessing support in the future.
Stick to the facts and suggestions, don't provide hope where we're not going to
implement complexity that we'd rather the user implement themselves when
needed.
* gh-124370: Add "howto" for free-threaded Python
This is a guide aimed at people writing Python code, as oppposed to the
existing guide for C API extension authors.
* Add missing new line
* Update Doc/howto/free-threading-python.rst
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
* interned -> immortalized
* Apply suggestions from code review
Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>
* Update Doc/howto/free-threading-python.rst
Co-authored-by: mpage <mpage@cs.stanford.edu>
* Update docs
* Apply suggestions from code review
Co-authored-by: Carol Willing <carolcode@willingconsulting.com>
* A few more updates
* Additional comment on immortal objects
* Mention specializing adaptive interpreter
* Remove trailing whitespace
* Remove mention of C macro
---------
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>
Co-authored-by: mpage <mpage@cs.stanford.edu>
Co-authored-by: Carol Willing <carolcode@willingconsulting.com>
Corrected some grammar and spelling issues in documentation.
Co-authored-by: Russell Keith-Magee <russell@keith-magee.com>
Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
PyDict_Next no longer locks the dictionary in the free-threaded build. Locking
around individual PyDict_Next calls is not sufficient because the function
returns borrowed references and because it allows concurrent modifications
during the iteraiton loop.
The internal locking also interferes with correct external synchronization
because it may suspend outer critical sections created by the caller.
Charles Machalow