This PR sets up tagged pointers for CPython.
The general idea is to create a separate struct _PyStackRef for everything on the evaluation stack to store the bits. This forces the C compiler to warn us if we try to cast things or pull things out of the struct directly.
Only for free threading: We tag the low bit if something is deferred - that means we skip incref and decref operations on it. This behavior may change in the future if Mark's plans to defer all objects in the interpreter loop pans out.
This implies a strict stack reference discipline is required. ALL incref and decref operations on stackrefs must use the stackref variants. It is unsafe to untag something then do normal incref/decref ops on it.
The new incref and decref variants are called dup and close. They mimic a "handle" API operating on these stackrefs.
Please read Include/internal/pycore_stackref.h for more information!
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Co-authored-by: Mark Shannon <9448417+markshannon@users.noreply.github.com>
Remove the const qualifier of the argument of functions:
* _PyLong_IsCompact()
* _PyLong_CompactValue()
Py_TYPE() argument is not const.
Fix the compiler warning:
Include/cpython/longintrepr.h: In function ‘_PyLong_CompactValue’:
Include/pyport.h:19:31: error: cast discards ‘const’ qualifier from
pointer target type [-Werror=cast-qual]
(...)
Include/cpython/longintrepr.h:133:30: note: in expansion of macro
‘Py_TYPE’
assert(PyType_HasFeature(Py_TYPE(op), Py_TPFLAGS_LONG_SUBCLASS));
Add dedicated subsection for `pathlib.owner()`, `group()`, `chmod()` and
`lchmod()`.
Co-authored-by: Hugo van Kemenade <1324225+hugovk@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.
Moves the logic to update the type's dictionary to its own function in order
to make the lock scoping more clear.
Also, ensure that `name` is decref'd on the error path.
PyUnicode_FromFormat() no longer produces the ending \ufffd
character for truncated C string when use precision with %s and %V.
It now truncates the string before the start of truncated multibyte sequences.
The integer part of the timestamp can be rounded up, while the millisecond
calculation truncates, causing the log timestamp to be wrong by up to 999 ms
(affected roughly 1 in 8 million timestamps).
Add `pathlib.Path.copytree()` method, which recursively copies one
directory to another.
This differs from `shutil.copytree()` in the following respects:
1. Our method has a *follow_symlinks* argument, whereas shutil's has a
*symlinks* argument with an inverted meaning.
2. Our method lacks something like a *copy_function* argument. It always
uses `Path.copy()` to copy files.
3. Our method lacks something like a *ignore_dangling_symlinks* argument.
Instead, users can filter out danging symlinks with *ignore*, or
ignore exceptions with *on_error*
4. Our *ignore* argument is a callable that accepts a single path object,
whereas shutil's accepts a path and a list of child filenames.
5. We add an *on_error* argument, which is a callable that accepts
an `OSError` instance. (`Path.walk()` also accepts such a callable).
Co-authored-by: Nice Zombies <nineteendo19d0@gmail.com>