During development of the limited API support for PySide,
we saw an error in a macro that accessed a type field.
This patch fixes the 7 errors in the Python headers.
Macros which were not written as capitals were implemented
as function.
To do the necessary analysis again, a script was included that
parses all headers and looks for "->tp_" in serctions which can
be reached with active limited API.
It is easily possible to call this script as a test.
Error listing:
../../Include/objimpl.h:243
#define PyObject_IS_GC(o) (PyType_IS_GC(Py_TYPE(o)) && \
(Py_TYPE(o)->tp_is_gc == NULL || Py_TYPE(o)->tp_is_gc(o)))
Action: commented only
../../Include/objimpl.h:362
#define PyType_SUPPORTS_WEAKREFS(t) ((t)->tp_weaklistoffset > 0)
Action: commented only
../../Include/objimpl.h:364
#define PyObject_GET_WEAKREFS_LISTPTR(o) \
((PyObject **) (((char *) (o)) + Py_TYPE(o)->tp_weaklistoffset))
Action: commented only
../../Include/pyerrors.h:143
#define PyExceptionClass_Name(x) \
((char *)(((PyTypeObject*)(x))->tp_name))
Action: implemented function
../../Include/abstract.h:593
#define PyIter_Check(obj) \
((obj)->ob_type->tp_iternext != NULL && \
(obj)->ob_type->tp_iternext != &_PyObject_NextNotImplemented)
Action: implemented function
../../Include/abstract.h:713
#define PyIndex_Check(obj) \
((obj)->ob_type->tp_as_number != NULL && \
(obj)->ob_type->tp_as_number->nb_index != NULL)
Action: implemented function
../../Include/abstract.h:924
#define PySequence_ITEM(o, i)\
( Py_TYPE(o)->tp_as_sequence->sq_item(o, i) )
Action: commented only
METH_NOARGS functions need only a single argument but they are cast
into a PyCFunction, which takes two arguments. This triggers an
invalid function cast warning in gcc8 due to the argument mismatch.
Fix this by adding a dummy unused argument.
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.
* Added new opcode END_ASYNC_FOR.
* Setting global StopAsyncIteration no longer breaks "async for" loops.
* Jumping into an "async for" loop is now disabled.
* Jumping out of an "async for" loop no longer corrupts the stack.
* Simplify the compiler.
Multi-phase initialized modules allow m_traverse to be called while the
module is still being initialized, so module authors may need to account
for that.
The commit removes one unnecessary "if" clause in genobject.c. That "if" clause was masking un-awaited coroutines warnings just to make writing unittests more convenient.
Better account for single-line compound statements and
semi-colon separated statements when suggesting
Py3 replacements for Py2 print statements.
Initial patch by Nitish Chandra.