Fix clang ubsan (undefined behavior sanitizer) warnings in dictobject.c by
adjusting how the internal struct _dictkeysobject shared keys structure is
declared.
This remains ABI compatible. We get rid of the union at the end of the
struct being used for conveinence to avoid typecasting in favor of char[]
variable length array at the end of a struct. This is known to clang to be
used for variable sized objects and will not cause an undefined behavior
problem. Similarly, char arrays do not have strict aliasing undefined
behavior when cast.
PEP-007 does not currently list variable length arrays (VLAs) as allowed
in our subset of C99. If this turns out to be a problem, the fix to this is
to change the char `dk_indices[]` into `dk_indices[1]` and restore the
three size computation subtractions this change removes:
`- Py_MEMBER_SIZE(PyDictKeysObject, dk_indices)`
If this works as is I'll make a separate PR to update PEP-007.
dictview_repr(): Use a Py_ReprEnter() / Py_ReprLeave() pair to check
for recursion, and produce "..." if so.
test_recursive_repr(): Check for the string rather than a
RecursionError. (Test cannot be any tighter as contents are
implementation-dependent.)
test_deeply_nested_repr(): Add new test, replacing the original
test_recursive_repr(). It checks that a RecursionError is raised in
the case of a non-recursive but deeply nested structure. (Very
similar to what test_repr_deep() in test/test_dict.py does for a
normal dict.)
OrderedDictTests: Add new test case, to test behavior on OrderedDict
instances containing their own values() or items().
* Add Py_UNREACHABLE() as an alias to abort().
* Use Py_UNREACHABLE() instead of assert(0)
* Convert more unreachable code to use Py_UNREACHABLE()
* Document Py_UNREACHABLE() and a few other macros.
* group the (stateful) runtime globals into various topical structs
* consolidate the topical structs under a single top-level _PyRuntimeState struct
* add a check-c-globals.py script that helps identify runtime globals
Other globals are excluded (see globals.txt and check-c-globals.py).
Make a non-Py_DEBUG, asserts-enabled build of CPython possible. This means
making sure helper functions are defined when NDEBUG is not defined, not
just when Py_DEBUG is defined.
Also fix a division-by-zero in obmalloc.c that went unnoticed because in Py_DEBUG mode, elsize is never zero.
Issue #29311: dict.get() and dict.setdefault() methods now use Argument Clinic
to parse arguments. Their calling convention changes from METH_VARARGS to
METH_FASTCALL which avoids the creation of a temporary tuple.
The signature of docstrings is also enhanced. For example,
get(...)
becomes:
get(self, key, default=None, /)
Issue #28858: The change b9c9691c72c5 introduced a regression. It seems like
_PyObject_CallArg1() uses more stack memory than
PyObject_CallFunctionObjArgs().
* PyObject_CallFunctionObjArgs(func, NULL) => _PyObject_CallNoArg(func)
* PyObject_CallFunctionObjArgs(func, arg, NULL) => _PyObject_CallArg1(func, arg)
PyObject_CallFunctionObjArgs() allocates 40 bytes on the C stack and requires
extra work to "parse" C arguments to build a C array of PyObject*.
_PyObject_CallNoArg() and _PyObject_CallArg1() are simpler and don't allocate
memory on the C stack.
This change is part of the fastcall project. The change on listsort() is
related to the issue #23507.
Issue #28127: Add a function to check that a dictionary remains consistent
after any change.
By default, tables are not checked, only basic attributes. Define DEBUG_PYDICT
(ex: gcc -D DEBUG_PYDICT) to also check dictionary "content".
Issue #28040: Fix _PyDict_DelItem_KnownHash() and _PyDict_Pop(): convert
splitted table to combined table to be able to delete the item.
Write an unit test for the issue.
Patch by INADA Naoki.
Issue #26058: Add a new private version to the builtin dict type, incremented
at each dictionary creation and at each dictionary change.
Implementation of the PEP 509.
Issue #27350: `dict` implementation is changed like PyPy. It is more compact
and preserves insertion order.
_PyDict_Dummy() function has been removed.
Disable test_gdb: python-gdb.py is not updated yet to the new structure of
compact dictionaries (issue #28023).
Patch written by INADA Naoki.
Issue #26154: Add a new private _PyThreadState_UncheckedGet() function which
gets the current thread state, but don't call Py_FatalError() if it is NULL.
Python 3.5.1 removed the _PyThreadState_Current symbol from the Python C API to
no more expose complex and private atomic types. Atomic types depends on the
compiler or can even depend on compiler options. The new function
_PyThreadState_UncheckedGet() allows to get the variable value without having
to care of the exact implementation of atomic types.
Changes:
* Replace direct usage of the _PyThreadState_Current variable with a call to
_PyThreadState_UncheckedGet().
* In pystate.c, replace direct usage of the _PyThreadState_Current variable
with the PyThreadState_GET() macro for readability.
* Document also PyThreadState_Get() in pystate.h
Ville Skyttä
Gregory P. Smith
INADA Naoki
bennorth
Serhiy Storchaka
Yury Selivanov
luzpaz
Barry Warsaw
Eric Snow
T. Wouters
Victor Stinner
Antoine Pitrou
INADA Naoki
Raymond Hettinger
doko@ubuntu.com
Berker Peksag
Benjamin Peterson
R David Murray