PyType_HasFeature() now always calls PyType_GetFlags() to hide
implementation details. Previously, it accessed directly the
PyTypeObject.tp_flags member when the limited C API was not used.
Add fast inlined version _PyType_HasFeature() and _PyType_IS_GC()
for object.c and typeobject.c.
The PyObject_NEW() macro becomes an alias to the PyObject_New()
macro, and the PyObject_NEW_VAR() macro becomes an alias to the
PyObject_NewVar() macro, to hide implementation details. They no
longer access directly the PyTypeObject.tp_basicsize member.
Exclude _PyObject_SIZE() and _PyObject_VAR_SIZE() macros from
the limited C API.
Replace PyObject_NEW() with PyObject_New() and replace
PyObject_NEW_VAR() with PyObject_NewVar().
Convert the PyObject_GET_WEAKREFS_LISTPTR() macro to a function to
hide implementation details: the macro accessed directly to the
PyTypeObject.tp_weaklistoffset member.
Add _PyObject_GET_WEAKREFS_LISTPTR() static inline function to the
internal C API.
Py_TRASHCAN_BEGIN_CONDITION and Py_TRASHCAN_END macro no longer
access PyThreadState attributes, but call new private
_PyTrash_begin() and _PyTrash_end() functions which hide
implementation details.
Move the static inline function flavor of Py_EnterRecursiveCall() and
Py_LeaveRecursiveCall() to the internal C API: they access
PyThreadState attributes. The limited C API provides regular
functions which hide implementation details.
In the limited C API, PyObject_INIT() and PyObject_INIT_VAR() are now
defined as aliases to PyObject_Init() and PyObject_InitVar() to make
their implementation opaque. It avoids to leak implementation details
in the limited C API.
Exclude the following functions from the limited C API, move them
from object.h to cpython/object.h:
* _Py_NewReference()
* _Py_ForgetReference()
* _PyTraceMalloc_NewReference()
* _Py_GetRefTotal()
The macro is defined after Py_DECREF() and so is no longer used by
Py_DECREF().
Moving _Py_Dealloc() macro back from cpython/object.h to object.h
would require to move a lot of definitions as well: PyTypeObject and
many related types used by PyTypeObject.
Keep _Py_Dealloc() as an opaque function call to avoid leaking
implementation details in the limited C API (object.h): remove
_Py_Dealloc() macro from cpython/object.h.
_Py_NewReference() becomes a regular opaque function, rather than a
static inline function in the C API (object.h), to better hide
implementation details.
Move _Py_tracemalloc_config from public pymem.h to internal
pycore_pymem.h header.
Make _Py_AddToAllObjects() private.
* Remove _Py_INC_REFTOTAL and _Py_DEC_REFTOTAL macros: modify
directly _Py_RefTotal.
* _Py_ForgetReference() is no longer defined if the Py_TRACE_REFS
macro is not defined.
* Remove _Py_NewReference() implementation from object.c:
unify the two implementations in object.h inline function.
* Fix Py_TRACE_REFS build: _Py_INC_TPALLOCS() macro has been removed.
Rename init_slotdefs() to _PyTypes_InitSlotDefs() and add a return
value of type PyStatus. The function is now called exactly once from
_PyTypes_Init(). Replace calls to init_slotdefs() with an assertion
checking that slotdefs is initialized.
Replace Py_FatalError() with _PyObject_ASSERT_FAILED_MSG() in
object.c and typeobject.c to also dump the involved Python object on
a fatal error. It should ease debug when such fatal error occurs.
If the double linked list is inconsistent, _Py_ForgetReference() no
longer dumps previous and next objects in the fatal error, it now
only dumps the current object. It ensures that the error message
is displayed even if dumping the object does crash Python.
Enhance _Py_ForgetReference() error messages;
_PyObject_ASSERT_FAILED_MSG() logs the "_Py_ForgetReference" function
name.
Additional note: the `method_check_args` function in `Objects/descrobject.c` is written in such a way that it applies to all kinds of descriptors. In particular, a future re-implementation of `wrapper_descriptor` could use that code.
CC @vstinner @encukou
https://bugs.python.org/issue37645
Automerge-Triggered-By: @encukou
* Add _Py_EnterRecursiveCall() and _Py_LeaveRecursiveCall() which
require a tstate argument.
* Pass tstate to _Py_MakeRecCheck() and _Py_CheckRecursiveCall().
* Convert Py_EnterRecursiveCall() and Py_LeaveRecursiveCall() macros
to static inline functions.
_PyThreadState_GET() is the most efficient way to get the tstate, and
so using it with _Py_EnterRecursiveCall() and
_Py_LeaveRecursiveCall() should be a little bit more efficient than
using Py_EnterRecursiveCall() and Py_LeaveRecursiveCall() which use
the "slower" PyThreadState_GET().
Some objects like Py_None are not initialized with conventional means
that prepare the circular linked list pointers, leaving them unlinked
from the rest of the objects. For those objects, NULL pointers does
not mean that they are freed, so we need to skip the check in those
cases.
bpo-36389, bpo-38376: The _PyObject_CheckConsistency() function is
now also available in release mode. For example, it can be used to
debug a crash in the visit_decref() function of the GC.
Modify the following functions to also work in release mode:
* _PyDict_CheckConsistency()
* _PyObject_CheckConsistency()
* _PyType_CheckConsistency()
* _PyUnicode_CheckConsistency()
Other changes:
* _PyMem_IsPtrFreed(ptr) now also returns 1 if ptr is NULL
(equals to 0).
* _PyBytesWriter_CheckConsistency() now returns 1 and is only used
with assert().
* Reorder _PyObject_Dump() to write safe fields first, and only
attempt to render repr() at the end.
It is now allowed to add new fields at the end of the PyTypeObject struct without having to allocate a dedicated compatibility flag in tp_flags.
This will reduce the risk of running out of bits in the 32-bit tp_flags value.
* Add _PyInitError functions:
* _PyInitError_Ok()
* _PyInitError_Error()
* _PyInitError_NoMemory()
* _PyInitError_Exit()
* _PyInitError_IsError()
* _PyInitError_IsExit()
* _PyInitError_Failed()
* frozenmain.c and _testembed.c now use functions rather than macros.
* Move _Py_INIT_xxx() macros to the internal API.
* Move _PyWstrList_INIT macro to the internal API.
Add a new _PyObject_CheckConsistency() function which can be used to
help debugging. The function is available in release mode.
Add a 'check_content' parameter to _PyDict_CheckConsistency().
Modify CLEANBYTE, DEADDYTE and FORBIDDENBYTE constants: use 0xCD,
0xDD and 0xFD, rather than 0xCB, 0xBB and 0xFB, to use the same byte
patterns than Windows CRT debug malloc() and free().
Replace _PyMem_IsFreed() function with _PyMem_IsPtrFreed() inline
function. The function is now way more efficient, it became a simple
comparison on integers, rather than a short loop. It detects also
uninitialized bytes and "forbidden bytes" filled by debug hooks
on memory allocators.
Add unit tests on _PyObject_IsFreed().
Hai Shi
Victor Stinner
Andy Lester
MojoVampire
Jeroen Demeyer
Pablo Galindo
Victor Stinner
Min ho Kim
Inada Naoki
Jeroen Demeyer
Antoine Pitrou
Steve Dower
penguindustin
Zackery Spytz