Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

UBSan: Calling a function through pointer to incorrect function type is undefined behavior #111178

Open
chrstphrchvz opened this issue Oct 22, 2023 · 24 comments
Labels
topic-C-API type-bug An unexpected behavior, bug, or error

Comments

@chrstphrchvz
Copy link
Contributor

chrstphrchvz commented Oct 22, 2023

Bug report

Bug description:

UBSan (UndefinedBehaviorSanitizer) in LLVM.org Clang 17 makes -fsanitize=function available for C; previously, it was only for C++. (So it may also be made available in future Apple Xcode clang and GCC.) By default, it is implied by -fsanitize=undefined (which is what ./configure --with-undefined-behavior-sanitizer uses), but it can be disabled using -fno-sanitize=function.

For a project such as CPython, which has long relied on function pointers for callbacks, yet seems to have only required that callbacks behave as expected under typical ABI calling conventions, rather than more strictly be declared/defined as a type compatible with the function pointer they will be called as, this leads to numerous errors from UBSan.

Examples when starting Python REPL:
% ./python.exe           
Objects/object.c:2731:5: runtime error: call to function list_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
listobject.c:347: note: list_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/object.c:2731:5 in 
Objects/object.c:878:16: runtime error: call to function long_hash through pointer to incorrect function type 'long (*)(struct _object *)'
longobject.c:3295: note: long_hash defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/object.c:878:16 in 
Include/internal/pycore_object.h:365:43: runtime error: call to function type_is_gc through pointer to incorrect function type 'int (*)(struct _object *)'
typeobject.c:5347: note: type_is_gc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Include/internal/pycore_object.h:365:43 in 
Objects/abstract.c:157:26: runtime error: call to function dict_subscript through pointer to incorrect function type 'struct _object *(*)(struct _object *, struct _object *)'
dictobject.c:2511: note: dict_subscript defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/abstract.c:157:26 in 
Objects/abstract.c:2954:14: runtime error: call to function tupleiter_next through pointer to incorrect function type 'struct _object *(*)(struct _object *)'
tupleobject.c:999: note: tupleiter_next defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/abstract.c:2954:14 in 
Objects/abstract.c:236:19: runtime error: call to function dict_ass_sub through pointer to incorrect function type 'int (*)(struct _object *, struct _object *, struct _object *)'
dictobject.c:2546: note: dict_ass_sub defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/abstract.c:236:19 in 
Objects/call.c:242:18: runtime error: call to function type_call through pointer to incorrect function type 'struct _object *(*)(struct _object *, struct _object *, struct _object *)'
typeobject.c:1647: note: type_call defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/call.c:242:18 in 
Objects/typeobject.c:10309:24: runtime error: call to function classmethod_get through pointer to incorrect function type 'struct _object *(*)(struct _object *, struct _object *, struct _object *)'
descrobject.c:94: note: classmethod_get defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/typeobject.c:10309:24 in 
Modules/gcmodule.c:493:16: runtime error: call to function list_traverse through pointer to incorrect function type 'int (*)(struct _object *, int (*)(struct _object *, void *), void *)'
listobject.c:2704: note: list_traverse defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Modules/gcmodule.c:493:16 in 
Modules/gcmodule.c:605:20: runtime error: call to function list_traverse through pointer to incorrect function type 'int (*)(struct _object *, int (*)(struct _object *, void *), void *)'
listobject.c:2704: note: list_traverse defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Modules/gcmodule.c:605:20 in 
Objects/dictobject.c:3569:17: runtime error: call to function visit_reachable through pointer to incorrect function type 'int (*)(struct _object *, void *)'
gcmodule.c:502: note: visit_reachable defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/dictobject.c:3569:17 in 
Objects/descrobject.c:694:5: runtime error: call to function visit_reachable through pointer to incorrect function type 'int (*)(struct _object *, void *)'
gcmodule.c:502: note: visit_reachable defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/descrobject.c:694:5 in 
[…]
Objects/typeobject.c:4892:19: runtime error: call to function classmethod_get through pointer to incorrect function type 'struct _object *(*)(struct _object *, struct _object *, struct _object *)'
descrobject.c:94: note: classmethod_get defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/typeobject.c:4892:19 in 
Python/generated_cases.c.h:3859:17: runtime error: call to function func_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
funcobject.c:913: note: func_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:3859:17 in 
Objects/object.c:1442:19: runtime error: call to function member_get through pointer to incorrect function type 'struct _object *(*)(struct _object *, struct _object *, struct _object *)'
descrobject.c:160: note: member_get defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/object.c:1442:19 in 
Objects/object.c:1503:15: runtime error: call to function method_get through pointer to incorrect function type 'struct _object *(*)(struct _object *, struct _object *, struct _object *)'
descrobject.c:136: note: method_get defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/object.c:1503:15 in 
Python/generated_cases.c.h:3857:13: runtime error: call to function meth_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
methodobject.c:160: note: meth_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:3857:13 in 
Objects/typeobject.c:2212:19: runtime error: call to function method_get through pointer to incorrect function type 'struct _object *(*)(struct _object *, struct _object *, struct _object *)'
descrobject.c:136: note: method_get defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/typeobject.c:2212:19 in 
Objects/descrobject.c:188:16: runtime error: call to function func_get_name through pointer to incorrect function type 'struct _object *(*)(struct _object *, void *)'
funcobject.c:582: note: func_get_name defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/descrobject.c:188:16 in 
Python/generated_cases.c.h:3248:20: runtime error: call to function tupleiter_next through pointer to incorrect function type 'struct _object *(*)(struct _object *)'
tupleobject.c:999: note: tupleiter_next defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:3248:20 in 
Objects/object.c:1564:19: runtime error: call to function member_set through pointer to incorrect function type 'int (*)(struct _object *, struct _object *, struct _object *)'
descrobject.c:227: note: member_set defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/object.c:1564:19 in 
Objects/descrobject.c:241:16: runtime error: call to function func_set_name through pointer to incorrect function type 'int (*)(struct _object *, struct _object *, void *)'
funcobject.c:588: note: func_set_name defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/descrobject.c:241:16 in 
Python/generated_cases.c.h:3364:21: runtime error: call to function tupleiter_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
tupleobject.c:984: note: tupleiter_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:3364:21 in 
Python/ceval.c:591:5: runtime error: call to function func_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
funcobject.c:913: note: func_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/ceval.c:591:5 in 
Objects/object.c:1031:18: runtime error: call to function _Py_module_getattro through pointer to incorrect function type 'struct _object *(*)(struct _object *, struct _object *)'
moduleobject.c:877: note: _Py_module_getattro defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/object.c:1031:18 in 
Objects/abstract.c:2895:25: runtime error: call to function dictitems_iter through pointer to incorrect function type 'struct _object *(*)(struct _object *)'
dictobject.c:5180: note: dictitems_iter defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/abstract.c:2895:25 in 
Python/generated_cases.c.h:3193:13: runtime error: call to function dictview_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
dictobject.c:4587: note: dictview_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:3193:13 in 
Python/ceval.c:1929:13: runtime error: call to function tupleiter_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
tupleobject.c:984: note: tupleiter_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/ceval.c:1929:13 in 
Objects/abstract.c:2334:19: runtime error: call to function tuplecontains through pointer to incorrect function type 'int (*)(struct _object *, struct _object *)'
tupleobject.c:354: note: tuplecontains defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/abstract.c:2334:19 in 
Objects/typeobject.c:1698:19: runtime error: call to function AttributeError_init through pointer to incorrect function type 'int (*)(struct _object *, struct _object *, struct _object *)'
exceptions.c:2279: note: AttributeError_init defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/typeobject.c:1698:19 in 
Python/generated_cases.c.h:1351:13: runtime error: call to function AttributeError_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
exceptions.c:2315: note: AttributeError_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:1351:13 in 
Python/generated_cases.c.h:623:13: runtime error: call to function tupledealloc through pointer to incorrect function type 'void (*)(struct _object *)'
tupleobject.c:187: note: tupledealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:623:13 in 
Python/generated_cases.c.h:749:13: runtime error: call to function tupledealloc through pointer to incorrect function type 'void (*)(struct _object *)'
tupleobject.c:187: note: tupledealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:749:13 in 
Python/generated_cases.c.h:3809:17: runtime error: call to function method_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
classobject.c:236: note: method_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:3809:17 in 
Objects/descrobject.c:393:24: runtime error: call to function dict_pop through pointer to incorrect function type 'struct _object *(*)(struct _object *, struct _object *const *, long)'
dictobject.c.h:138: note: dict_pop defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/descrobject.c:393:24 in 
Python/generated_cases.c.h:3260:17: runtime error: call to function dictiter_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
dictobject.c:4047: note: dictiter_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:3260:17 in 
Objects/object.c:1699:15: runtime error: call to function long_bool through pointer to incorrect function type 'int (*)(struct _object *)'
longobject.c:4890: note: long_bool defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/object.c:1699:15 in 
Python/generated_cases.c.h:4816:13: runtime error: call to function dict_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
dictobject.c:2373: note: dict_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:4816:13 in 
Python/generated_cases.c.h:3896:17: runtime error: call to function method_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
classobject.c:236: note: method_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:3896:17 in 
Python/generated_cases.c.h:4625:19: runtime error: call to function dict_pop through pointer to incorrect function type 'struct _object *(*)(struct _object *, struct _object *const *, long)'
dictobject.c.h:138: note: dict_pop defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:4625:19 in 
Objects/descrobject.c:467:24: runtime error: call to function list_append through pointer to incorrect function type 'struct _object *(*)(struct _object *, struct _object *)'
listobject.c:842: note: list_append defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/descrobject.c:467:24 in 
Include/internal/pycore_object.h:142:9: runtime error: call to function PyObject_Free through pointer to incorrect function type 'void (*)(struct _object *)'
obmalloc.c:829: note: PyObject_Free defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Include/internal/pycore_object.h:142:9 in 
Objects/call.c:361:18: runtime error: call to function type_call through pointer to incorrect function type 'struct _object *(*)(struct _object *, struct _object *, struct _object *)'
typeobject.c:1647: note: type_call defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/call.c:361:18 in 
Python/generated_cases.c.h:2931:13: runtime error: call to function tupledealloc through pointer to incorrect function type 'void (*)(struct _object *)'
tupleobject.c:187: note: tupledealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:2931:13 in 
Python/generated_cases.c.h:3362:25: runtime error: call to function tupledealloc through pointer to incorrect function type 'void (*)(struct _object *)'
tupleobject.c:187: note: tupledealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:3362:25 in 
Python/generated_cases.c.h:928:13: runtime error: call to function list_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
listobject.c:347: note: list_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:928:13 in 
Python/ceval.c:1604:5: runtime error: call to function tupledealloc through pointer to incorrect function type 'void (*)(struct _object *)'
tupleobject.c:187: note: tupledealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/ceval.c:1604:5 in 
Python/bltinmodule.c:378:16: runtime error: call to function gen_iternext through pointer to incorrect function type 'struct _object *(*)(struct _object *)'
genobject.c:609: note: gen_iternext defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/bltinmodule.c:378:16 in 
Objects/object.c:1702:15: runtime error: call to function list_length through pointer to incorrect function type 'long (*)(struct _object *)'
listobject.c:438: note: list_length defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/object.c:1702:15 in 
Python/generated_cases.c.h:3519:13: runtime error: call to function method_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
classobject.c:236: note: method_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:3519:13 in 
Objects/methodobject.c:540:18: runtime error: call to function rlock_acquire through pointer to incorrect function type 'struct _object *(*)(struct _object *, struct _object *, struct _object *)'
_threadmodule.c:314: note: rlock_acquire defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/methodobject.c:540:18 in 
Python/generated_cases.c.h:2767:13: runtime error: call to function list_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
listobject.c:347: note: list_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:2767:13 in 
Objects/methodobject.c:551:18: runtime error: call to function rlock_release through pointer to incorrect function type 'struct _object *(*)(struct _object *, struct _object *)'
_threadmodule.c:364: note: rlock_release defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/methodobject.c:551:18 in 
Objects/typeobject.c:2096:5: runtime error: call to function list_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
listobject.c:347: note: list_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/typeobject.c:2096:5 in 
Python/generated_cases.c.h:130:13: runtime error: call to function method_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
classobject.c:236: note: method_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:130:13 in 
Objects/object.c:1181:15: runtime error: call to function type_setattro through pointer to incorrect function type 'int (*)(struct _object *, struct _object *, struct _object *)'
typeobject.c:4938: note: type_setattro defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/object.c:1181:15 in 
Python/generated_cases.c.h:1510:13: runtime error: call to function tupledealloc through pointer to incorrect function type 'void (*)(struct _object *)'
tupleobject.c:187: note: tupledealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:1510:13 in 
Python/generated_cases.c.h:164:13: runtime error: call to function listiter_dealloc through pointer to incorrect function type 'void (*)(struct _object *)'
listobject.c:3222: note: listiter_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:164:13 in 
[…]

Modules/gcmodule.c:1033:24: runtime error: call to function _list_clear through pointer to incorrect function type 'int (*)(struct _object )'
listobject.c:597: note: _list_clear defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Modules/gcmodule.c:1033:24 in
Objects/abstract.c:62:26: runtime error: call to function list_length through pointer to incorrect function type 'long (
)(struct _object )'
listobject.c:438: note: list_length defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/abstract.c:62:26 in
Objects/abstract.c:270:19: runtime error: call to function dict_ass_sub through pointer to incorrect function type 'int (
)(struct _object *, struct _object *, struct _object *)'
dictobject.c:2546: note: dict_ass_sub defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/abstract.c:270:19 in
Python/bltinmodule.c:329:16: runtime error: call to function gen_iternext through pointer to incorrect function type 'struct _object ()(struct _object *)'
genobject.c:609: note: gen_iternext defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/bltinmodule.c:329:16 in
Objects/abstract.c:1141:18: runtime error: call to function tupleconcat through pointer to incorrect function type 'struct _object ()(struct _object *, struct _object )'
tupleobject.c:443: note: tupleconcat defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/abstract.c:1141:18 in
Objects/abstract.c:440:15: runtime error: call to function bytes_buffer_getbuffer through pointer to incorrect function type 'int (
)(struct _object *, Py_buffer *, int)'
bytesobject.c:1663: note: bytes_buffer_getbuffer defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/abstract.c:440:15 in
Objects/methodobject.c:441:24: runtime error: call to function int_from_bytes through pointer to incorrect function type 'struct _object ()(struct _object *, struct _object *const *, long, struct _object )'
longobject.c.h:396: note: int_from_bytes defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/methodobject.c:441:24 in
[…]
Python/generated_cases.c.h:4814:13: runtime error: call to function method_dealloc through pointer to incorrect function type 'void (
)(struct _object )'
classobject.c:236: note: method_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:4814:13 in
Python/generated_cases.c.h:4815:13: runtime error: call to function tupledealloc through pointer to incorrect function type 'void (
)(struct _object )'
tupleobject.c:187: note: tupledealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:4815:13 in
Python/generated_cases.c.h:1529:13: runtime error: call to function tupledealloc through pointer to incorrect function type 'void (
)(struct _object )'
tupleobject.c:187: note: tupledealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:1529:13 in
Python/generated_cases.c.h:648:17: runtime error: call to function slice_dealloc through pointer to incorrect function type 'void (
)(struct _object *)'
sliceobject.c:359: note: slice_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:648:17 in
Objects/abstract.c:953:13: runtime error: call to function long_add through pointer to incorrect function type 'struct _object ()(struct _object *, struct _object )'
longobject.c:3473: note: long_add defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/abstract.c:953:13 in
Python/generated_cases.c.h:3322:21: runtime error: call to function listiter_dealloc through pointer to incorrect function type 'void (
)(struct _object )'
listobject.c:3222: note: listiter_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:3322:21 in
Python/generated_cases.c.h:2821:13: runtime error: call to function PyObject_Free through pointer to incorrect function type 'void (
)(struct _object *)'
obmalloc.c:829: note: PyObject_Free defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:2821:13 in
Objects/listobject.c:946:26: runtime error: call to function gen_iternext through pointer to incorrect function type 'struct _object ()(struct _object *)'
genobject.c:609: note: gen_iternext defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/listobject.c:946:26 in
Python/generated_cases.c.h:4503:19: runtime error: call to function list_extend through pointer to incorrect function type 'struct _object ()(struct _object *, struct _object )'
listobject.c:861: note: list_extend defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:4503:19 in
Python/generated_cases.c.h:4507:13: runtime error: call to function gen_dealloc through pointer to incorrect function type 'void (
)(struct _object )'
genobject.c:128: note: gen_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:4507:13 in
Python/generated_cases.c.h:2378:17: runtime error: call to function structseq_dealloc through pointer to incorrect function type 'void (
)(struct _object )'
structseq.c:119: note: structseq_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:2378:17 in
Python/ceval.c:1605:5: runtime error: call to function dict_dealloc through pointer to incorrect function type 'void (
)(struct _object )'
dictobject.c:2373: note: dict_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/ceval.c:1605:5 in
Python/generated_cases.c.h:1548:13: runtime error: call to function tupledealloc through pointer to incorrect function type 'void (
)(struct _object *)'
tupleobject.c:187: note: tupledealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:1548:13 in
Objects/descrobject.c:439:24: runtime error: call to function _io_FileIO_isatty through pointer to incorrect function type 'struct _object ()(struct _object *, struct _object *)'
fileio.c.h:532: note: _io_FileIO_isatty defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/descrobject.c:439:24 in
Objects/methodobject.c:484:24: runtime error: call to function _io_FileIO_readall through pointer to incorrect function type 'struct _object ()(struct _object *, struct _object *)'
fileio.c.h:284: note: _io_FileIO_readall defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/methodobject.c:484:24 in
Objects/descrobject.c:372:24: runtime error: call to function _io_FileIO_close through pointer to incorrect function type 'struct _object ()(struct _object *, struct _typeobject *, struct _object *const *, unsigned long, struct _object *)'
fileio.c.h:29: note: _io_FileIO_close defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/descrobject.c:372:24 in
Objects/object.c:783:15: runtime error: call to function bytes_richcompare through pointer to incorrect function type 'struct _object ()(struct _object *, struct _object , int)'
bytesobject.c:1524: note: bytes_richcompare defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/object.c:783:15 in
Python/generated_cases.c.h:650:13: runtime error: call to function memory_dealloc through pointer to incorrect function type 'void (
)(struct _object )'
memoryobject.c:1141: note: memory_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:650:13 in
Objects/abstract.c:804:9: runtime error: call to function memory_releasebuf through pointer to incorrect function type 'void (
)(struct _object *, Py_buffer *)'
memoryobject.c:1593: note: memory_releasebuf defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/abstract.c:804:9 in
Objects/abstract.c:1950:25: runtime error: call to function list_item through pointer to incorrect function type 'struct _object ()(struct _object , long)'
listobject.c:460: note: list_item defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/abstract.c:1950:25 in
Modules/timemodule.c:2087:5: runtime error: call to function visit_reachable through pointer to incorrect function type 'int (
)(struct _object *, void )'
gcmodule.c:502: note: visit_reachable defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Modules/timemodule.c:2087:5 in
Python/generated_cases.c.h:2660:21: runtime error: call to function set_dealloc through pointer to incorrect function type 'void (
)(struct _object )'
setobject.c:489: note: set_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:2660:21 in
Python/generated_cases.c.h:4440:13: runtime error: call to function tupledealloc through pointer to incorrect function type 'void (
)(struct _object )'
tupleobject.c:187: note: tupledealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:4440:13 in
Python/generated_cases.c.h:2822:13: runtime error: call to function PyObject_Free through pointer to incorrect function type 'void (
)(struct _object )'
obmalloc.c:829: note: PyObject_Free defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:2822:13 in
Python/generated_cases.c.h:2157:13: runtime error: call to function dict_dealloc through pointer to incorrect function type 'void (
)(struct _object *)'
dictobject.c:2373: note: dict_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:2157:13 in
Objects/typeobject.c:4872:19: runtime error: call to function getset_get through pointer to incorrect function type 'struct _object ()(struct _object *, struct _object *, struct _object )'
descrobject.c:180: note: getset_get defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/typeobject.c:4872:19 in
Python/generated_cases.c.h:4730:17: runtime error: call to function func_dealloc through pointer to incorrect function type 'void (
)(struct _object *)'
funcobject.c:913: note: func_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:4730:17 in
Objects/typeobject.c:4905:15: runtime error: call to function method_get through pointer to incorrect function type 'struct _object ()(struct _object *, struct _object *, struct _object )'
descrobject.c:136: note: method_get defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/typeobject.c:4905:15 in
Objects/typeobject.c:1863:16: runtime error: call to function tupletraverse through pointer to incorrect function type 'int (
)(struct _object , int ()(struct _object *, void *), void *)'
tupleobject.c:606: note: tupletraverse defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Objects/typeobject.c:1863:16 in
[…]
Include/internal/pycore_call.h:187:11: runtime error: call to function range_vectorcall through pointer to incorrect function type 'struct _object ()(struct _object *, struct _object *const *, unsigned long, struct _object )'
rangeobject.c:148: note: range_vectorcall defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Include/internal/pycore_call.h:187:11 in
Python/generated_cases.c.h:2878:13: runtime error: call to function mappingproxy_dealloc through pointer to incorrect function type 'void (
)(struct _object )'
descrobject.c:1160: note: mappingproxy_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:2878:13 in
Python/generated_cases.c.h:3320:25: runtime error: call to function list_dealloc through pointer to incorrect function type 'void (
)(struct _object )'
listobject.c:347: note: list_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:3320:25 in
Python/generated_cases.c.h:2766:13: runtime error: call to function set_dealloc through pointer to incorrect function type 'void (
)(struct _object )'
setobject.c:489: note: set_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:2766:13 in
Modules/_abc.c:52:5: runtime error: call to function visit_reachable through pointer to incorrect function type 'int (
)(struct _object *, void *)'
gcmodule.c:502: note: visit_reachable defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Modules/_abc.c:52:5 in
Python/bltinmodule.c:1408:25: runtime error: call to function tupleiter_next through pointer to incorrect function type 'struct _object ()(struct _object )'
tupleobject.c:999: note: tupleiter_next defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/bltinmodule.c:1408:25 in
Python/generated_cases.c.h:673:17: runtime error: call to function slice_dealloc through pointer to incorrect function type 'void (
)(struct _object *)'
sliceobject.c:359: note: slice_dealloc defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:673:17 in


(Omitting remaining errors due to GitHub comment length limit.)


Python 3.13.0a1+ (heads/patch-103194-dirty:0a6e69f9a2, Oct 21 2023, 14:45:09) [Clang 17.0.3 ] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>

Example workaround for the first error and likely many others, where instead of casting functions to incompatible pointers, the functions use compatible signatures and cast their parameter(s):

--- a/Objects/listobject.c
+++ b/Objects/listobject.c
@@ -343,8 +343,9 @@ PyList_Append(PyObject *op, PyObject *newitem)
 /* Methods */
 
 static void
-list_dealloc(PyListObject *op)
+list_dealloc(PyObject *self)
 {
+    PyListObject *op = (PyListObject *)self;
     Py_ssize_t i;
     PyObject_GC_UnTrack(op);
     Py_TRASHCAN_BEGIN(op, list_dealloc)
@@ -3104,7 +3105,7 @@ PyTypeObject PyList_Type = {
     "list",
     sizeof(PyListObject),
     0,
-    (destructor)list_dealloc,                   /* tp_dealloc */
+    list_dealloc,                               /* tp_dealloc */
     0,                                          /* tp_vectorcall_offset */
     0,                                          /* tp_getattr */
     0,                                          /* tp_setattr */

In other cases, it may be less disruptive to introduce a wrapper function with the correct signature:

@@ -615,6 +617,13 @@ _list_clear(PyListObject *a)
     return 0;
 }
 
+static int
+_list_clear_wrap(PyObject *self)
+{
+    PyListObject *a = (PyListObject *)self;
+    return _list_clear(a);
+}
+
 /* a[ilow:ihigh] = v if v != NULL.
  * del a[ilow:ihigh] if v == NULL.
  *
@@ -3123,7 +3133,7 @@ PyTypeObject PyList_Type = {
         _Py_TPFLAGS_MATCH_SELF | Py_TPFLAGS_SEQUENCE,  /* tp_flags */
     list___init____doc__,                       /* tp_doc */
     (traverseproc)list_traverse,                /* tp_traverse */
-    (inquiry)_list_clear,                       /* tp_clear */
+    _list_clear_wrap,                           /* tp_clear */
     list_richcompare,                           /* tp_richcompare */
     0,                                          /* tp_weaklistoffset */
     list_iter,                                  /* tp_iter */

Likely instances of this can be found at compile time using e.g. -Wcast-function-type (although this emits false positives for when the function pointer is cast back to the correct type before called, and this warning is suppressed by intermediate casts through (void *)):

Objects/listobject.c:3162:5: warning: cast from 'void (*)(PyListObject *)' to 'destructor' (aka 'void (*)(struct _object *)') converts to incompatible function type [-Wcast-function-type-strict]
 3162 |     (destructor)list_dealloc,                   /* tp_dealloc */
      |     ^~~~~~~~~~~~~~~~~~~~~~~~

I would be interested in combing through and replacing similar instances. But I would not be surprised if sooner or later I encounter an instance that is won’t-fix because it involves a stable API, or if I am told that this problem should be ignored because fixing it is too disruptive or requires disproportionate review effort. I am not aware how immediate any danger is from optimizing compilers exploiting this type of undefined behavior.

CPython versions tested on:

CPython main branch

Operating systems tested on:

macOS


Written by @picnixz:

For detecting the UBSan failures, contributors may configure Python with:

./configure                                                 \
    --with-pydebug                                          \
    --prefix="$(pwd)/build"                                 \
    CC=clang LD=clang                                       \
    CFLAGS="-fsanitize=function     -fsanitize-recover"     \
    LDFLAGS="-fsanitize=function    -fsanitize-recover"

The complete list of failures can be retrieved as follows:

PAT='runtime error: call to function (\w+) through pointer' && \
make -j12 2>&1 >/dev/null | \
    grep -E "$PAT" | \
    sed -r "s#^(.+): $PAT.+#\1@\2#g" | \
    sort -k1,2 -t@ -u | \
    awk 'BEGIN {
            PROCINFO["sorted_in"]="@ind_num_asc";
            FS=SUBSEP="@"
        } {
            A[$1][length(A[$1])+1]=$2
        } END {
            for (m in A) {
                for (i in A[m]) {
                    if (i == 1) printf "%s\n", m;
                    print "#", A[m][i]
                }
                print ""
            }
        }' | \
    sed -r "s#"$(pwd)"/?(\./)?(.+)#\2#g"

Note that different builds should be configured in order to hunt all UBSan failures (e.g., --with-trace-refs or --disable-gil to expose conditional compiled code guarded by macros).


Linked PRs

@thesamesam
Copy link
Contributor

See also http://maskray.me/blog/2022-12-18-control-flow-integrity#fsanitizefunction by @MaskRay for more background.

@gpshead
Copy link
Member

gpshead commented Nov 5, 2023

This is one example where the recent trend of thinking we should use specific types on our C API is not compatible with parts of our design. Things like your proposed change are likely good. I'd like to avoid gaining new -f flags to the compiler if possible. ABI considerations are something that could force the compiler flag issue.

In this case it's odd that this counts as undefined behavior. Reality: A pointer is always going to be a pointer regardless of what type it points to - one machine word. The standard is deficient.

@ArsenArsen
Copy link

A pointer is always going to be a pointer regardless of what type it points to - one machine word. The standard is deficient.

note that the standard requires that all pointers are of the same finite size, including FPs

@encukou
Copy link
Member

encukou commented Nov 5, 2023

the recent trend of thinking we should use specific types on our C API

That trend, as I understand it, is unrelated, or only tangentially related. It doesn't involve casting function types; and the discussions around it didn't involve type definition. Please don't conflate it with this issue.

@gpshead
Copy link
Member

gpshead commented Nov 5, 2023

My comment is more about seeing a function using the specific type. I didn't go looking to see if it has always been that way or was a recent change. Per the source history, this one has always been defined using PyListObject.

That it causes UBSAN issues is just something to be aware of if we do want to use specific types in more places.

@gpshead
Copy link
Member

gpshead commented Nov 5, 2023

A pointer is always going to be a pointer regardless of what type it points to - one machine word. The standard is deficient.

note that the standard requires that all pointers are of the same finite size, including FPs

Regardless of pointers all being the same size, the compiler behavior concern might be more to do with the structure aliasing concept rather than the pointer itself. I'd have to ask llvm folks. The answer likely wouldn't change what we need to deal with.

@gpshead
Copy link
Member

gpshead commented Nov 5, 2023

Poking around, we've got quite a few of these PyTypeObject function pointers that are cast in order to construct the structures with functions taking more specific types. The cleanup for clang-17's new UBSAN check will touch many files. (but is otherwise a pretty mechanical change - in most cases we can just change the parameter type to be generic and add a casting assignment to a local variable of the original name within the function to "launder" the type).

@encukou
Copy link
Member

encukou commented Nov 5, 2023

Struct casting & aliasing rules say that you can safely cast PyListObject * to PyObject * and back, and that you can safely mutate the object using both resulting pointers.
But when calling a function through an incompatible function pointer, there is no cast. PyListObject * and PyObject * are simply not “compatible”.

When compilers start punishing this, it'll be bad news. Pretty much all types defined in C use this pattern – not just in CPython core, but in third-party extensions as well. It's even in the tutorial: https://docs.python.org/3/extending/newtypes_tutorial.html#adding-data-and-methods-to-the-basic-example

I would not be surprised if sooner or later I encounter an instance that is won’t-fix because it involves a stable API, or if I am told that this problem should be ignored because fixing it is too disruptive or requires disproportionate review effort

The overwhelming majority of the fixes should be simple. It's the sheer number of them that will require disproportionate review effort.

@gpshead
Copy link
Member

gpshead commented Dec 6, 2023

I updated our Clang UBSAN buildbot last night, clang-17. So it fails the build on this issue now. =) https://buildbot.python.org/all/#/workers/2

@vstinner
Copy link
Member

vstinner commented Dec 6, 2023

See also http://maskray.me/blog/2022-12-18-control-flow-integrity#fsanitizefunction by @MaskRay for more background.

Oh no, this issue is related to Control Flow Integrity (CFI). I think that this problem should be treated seriously, more and more companies are enforcing CFI. It's better if Python can be adapted to respect CFI as soon as possible. CFI even started to be implemented at the hardware (CPU) level. The Linux kernel does its best to implement CFI to harden the kernel.

Recently, I added the _PyCFunction_CAST() macro with a long comment:

// Cast an function to the PyCFunction type to use it with PyMethodDef.
//
// This macro can be used to prevent compiler warnings if the first parameter
// uses a different pointer type than PyObject* (ex: METH_VARARGS and METH_O
// calling conventions).
//
// The macro can also be used for METH_FASTCALL and METH_VARARGS|METH_KEYWORDS
// calling conventions to avoid compiler warnings because the function has more
// than 2 parameters. The macro first casts the function to the
// "void func(void)" type to prevent compiler warnings.
//
// If a function is declared with the METH_NOARGS calling convention, it must
// have 2 parameters. Since the second parameter is unused, Py_UNUSED() can be
// used to prevent a compiler warning. If the function has a single parameter,
// it triggers an undefined behavior when Python calls it with 2 parameters
// (bpo-33012).
#define _PyCFunction_CAST(func) \
    _Py_CAST(PyCFunction, _Py_CAST(void(*)(void), (func)))

The problem is that PyMethodDef.ml_meth member type is:

typedef PyObject *(*PyCFunction)(PyObject *, PyObject *);

whereas Python uses calling convention with more or less parameters than PyCFunction or with other parameter types :-(

I think that we should decide a global strategy for this problem, rather than trying the whack-a-mole game with various strategies. It's a problem as bad a Python 2 PyObject structure inheritance which was not compatible with strict aliasing. This problem was solved with a new API, especially this macro:

#define PyObject_HEAD PyObject ob_base;

@vstinner
Copy link
Member

vstinner commented Dec 6, 2023

@encukou:

Struct casting & aliasing rules say that you can safely cast PyListObject * to PyObject * and back, and that you can safely mutate the object using both resulting pointers.

I have a different experience with casting from/to PyObject*. I discovered "type punning" issue the hard way in #98724

@chrstphrchvz
Copy link
Contributor Author

I have opened a couple of PRs for a few examples of this issue. I intended to separate them by codeowner(s), if that is helpful.

Some instances of this issue lead to far more errors than others; visit_reachable() seems to be the most common.

I am not aware how instances involving generated code should be handled:

cpython/Objects/listobject.c

Lines 1013 to 1017 in d384813

[clinic start generated code]*/
static PyObject *
py_list_extend(PyListObject *self, PyObject *iterable)
/*[clinic end generated code: output=b8e0bff0ceae2abd input=9a8376a8633ed3ba]*/

Objects/listobject.c:2911:5: warning: cast from 'PyObject *(*)(PyListObject *, PyObject *)' (aka 'struct _object *(*)(PyListObject *, struct _object *)') to 'PyCFunction' (aka 'struct _object *(*)(struct _object *, struct _object *)') converts to incompatible function type [-Wcast-function-type-strict]
 2911 |     PY_LIST_EXTEND_METHODDEF
      |     ^~~~~~~~~~~~~~~~~~~~~~~~
Objects/clinic/listobject.c.h:105:16: note: expanded from macro 'PY_LIST_EXTEND_METHODDEF'
  105 |     {"extend", (PyCFunction)py_list_extend, METH_O, py_list_extend__doc__},
      |                ^~~~~~~~~~~~~~~~~~~~~~~~~~~
Python/generated_cases.c.h:1626:19: runtime error: call to function py_list_extend through pointer to incorrect function type 'struct _object *(*)(struct _object *, struct _object *)'
listobject.c:1025: note: py_list_extend defined here
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior Python/generated_cases.c.h:1626:19 in 

@chrstphrchvz
Copy link
Contributor Author

I think that we should decide a global strategy for this problem, rather than trying the whack-a-mole game with various strategies.

Related to this point: how likely is it that instances of this issue will keep being introduced or reintroduced, at least without greater awareness and acceptance of the relevant C rules? How much does having CI run with -fsanitize=function or even -Werror=cast-function-type help prevent this?

@gpshead
Copy link
Member

gpshead commented Dec 6, 2023

how likely is it that instances of this issue will keep being introduced or reintroduced, at least without greater awareness and acceptance of the relevant C rules? How much does having CI run with -fsanitize=function or even -Werror=cast-function-type help prevent this?

It helps. Particularly once we've gotten to a stable point so that the ubsan build is not Red again. As people notice when things start failing after a change.

I believe a lot of what we do within our C code for these design patterns is cargo cult from other existing examples. So if we've cleaned things up in a consistent manner, including the code generators, to do something in a "right" way, that'll naturally become what gets done in new code.

encukou pushed a commit that referenced this issue Dec 6, 2023
…meters in slot typedefs table (GH-112742)

In the slot typedefs table, the parameter of `destructor`
and the first parameter of `traverseproc` should both be
`PyObject *` rather than `void *`.
Same for `inquiry`.
miss-islington pushed a commit to miss-islington/cpython that referenced this issue Dec 6, 2023
…` parameters in slot typedefs table (pythonGH-112742)

In the slot typedefs table, the parameter of `destructor`
and the first parameter of `traverseproc` should both be
`PyObject *` rather than `void *`.
Same for `inquiry`.
(cherry picked from commit 00cce0f)

Co-authored-by: Christopher Chavez <[email protected]>
miss-islington pushed a commit to miss-islington/cpython that referenced this issue Dec 6, 2023
…` parameters in slot typedefs table (pythonGH-112742)

In the slot typedefs table, the parameter of `destructor`
and the first parameter of `traverseproc` should both be
`PyObject *` rather than `void *`.
Same for `inquiry`.
(cherry picked from commit 00cce0f)

Co-authored-by: Christopher Chavez <[email protected]>
encukou pushed a commit that referenced this issue Dec 6, 2023
…r` parameters in slot typedefs table (GH-112742) (GH-112792)

gh-111178: Docs: fix `traverseproc`, `inquiry`, and `destructor` parameters in slot typedefs table (GH-112742)

In the slot typedefs table, the parameter of `destructor`
and the first parameter of `traverseproc` should both be
`PyObject *` rather than `void *`.
Same for `inquiry`.
(cherry picked from commit 00cce0f)

Co-authored-by: Christopher Chavez <[email protected]>
encukou pushed a commit that referenced this issue Dec 6, 2023
…r` parameters in slot typedefs table (GH-112742) (GH-112793)

gh-111178: Docs: fix `traverseproc`, `inquiry`, and `destructor` parameters in slot typedefs table (GH-112742)

In the slot typedefs table, the parameter of `destructor`
and the first parameter of `traverseproc` should both be
`PyObject *` rather than `void *`.
Same for `inquiry`.
(cherry picked from commit 00cce0f)

Co-authored-by: Christopher Chavez <[email protected]>
vstinner added a commit to vstinner/cpython that referenced this issue Oct 4, 2024
Rename also parameters/variables "o" to "ags" or "agw".
vstinner added a commit to vstinner/cpython that referenced this issue Oct 4, 2024
Rename also parameters/variables "o" to "ags" or "agw".
vstinner added a commit to vstinner/cpython that referenced this issue Oct 4, 2024
Rename also parameters/variables "o" to "ags" or "agw".
vstinner added a commit to vstinner/cpython that referenced this issue Oct 4, 2024
* Add "CAST" macros.
* Rename parameters/variables "o" to "ags", "agw" or "agt" in some
  functions.
vstinner added a commit to vstinner/cpython that referenced this issue Oct 4, 2024
* Add "CAST" macros.
* Rename parameters/variables "o" to "ags", "agw" or "agt" in some
  functions.
vstinner added a commit to vstinner/cpython that referenced this issue Oct 4, 2024
* Add "CAST" macros.
* Rename parameters/variables "o" to "ag", "ags", "agw" or "agt"
  in some functions.
@vstinner
Copy link
Member

vstinner commented Oct 4, 2024

I pushed a serie of changes to reduce the number of undefined behavior: fix the function signatures.

On the current main branch, running make and python -c pass warns about 39 function calls:

AttributeError_init
builtin_id
bytes_decode
cell_clear
code_hash
del_extensions_cache_value
deque_len
dict_fromkeys
dict_items
dict_pop
generic_init_subclass
gen_iternext
get_blksize
get_closed
ImportError_dealloc
inst_seq_traverse
int_from_bytes
_io_FileIO_close
_io_FileIO_readall
list_append
list_extend
local_traverse
lru_cache_call
match_group
namespace_traverse
partial_call
partial_vectorcall
pickle_free
PyObject_Free
range_subscript
reversed_next
set_done
set_pop
tb_traverse
tupleiter_dealloc
type_set_abstractmethods
type_set_annotations
typevar_typing_prepare_subst
unicode_ascii_iter_next

@vstinner
Copy link
Member

vstinner commented Oct 4, 2024

PyObject_Free

The problem comes from types using .tp_dealloc = (destructor)PyObject_Free: tp_dealloc prototype is:

typedef void (*destructor)(PyObject *);

whereas PyObject_Free() uses:

void PyObject_Free(void *ptr)

Having to add a wrapper function to cast PyObject* to void* sounds unconvenient and slow :-(


list_append

PyCFunction expects PyObject*:

typedef PyObject *(*PyCFunction)(PyObject *, PyObject *);

whereas list_append() in Objects/clinic/listobject.c.h expects PyListObject*:

static PyObject* list_append(PyListObject *self, PyObject *object)

This code is generated by Argument Clinic.

@picnixz
Copy link
Contributor

picnixz commented Oct 4, 2024

Here are the locations of all errors (on latest main):

Include/internal/pycore_call.h:167:11
# partial_vectorcall

Include/internal/pycore_object.h:231:9
# PyObject_Free

Objects/abstract.c:158:26
# range_subscript

Objects/abstract.c:2874:18
# gen_iternext

Objects/abstract.c:63:26
# deque_len

Objects/call.c:242:18
# partial_call

Objects/call.c:361:18
# lru_cache_call

Objects/descrobject.c:193:16
# get_blksize

Objects/descrobject.c:249:16
# type_set_abstractmethods

Objects/descrobject.c:324:24
# match_group

Objects/descrobject.c:380:24
# _io_FileIO_close

Objects/descrobject.c:401:24
# dict_pop

Objects/descrobject.c:420:24
# bytes_decode

Objects/descrobject.c:447:24
# dict_items

Objects/descrobject.c:475:24
# list_append

Objects/listobject.c:1194:26
# gen_iternext

Objects/methodobject.c:436:24
# dict_fromkeys

Objects/methodobject.c:452:24
# int_from_bytes

Objects/methodobject.c:495:24
# _io_FileIO_readall

Objects/methodobject.c:523:24
# _io_TextIOWrapper_write
# type___subclasscheck__

Objects/methodobject.c:551:18
# generic_init_subclass

Objects/moduleobject.c:784:9
# pickle_free

Objects/object.c:1066:16
# code_hash

Objects/object.c:1857:15
# deque_len

Objects/object.c:2888:5
# tupleiter_dealloc

Objects/typeobject.c:2184:19
# AttributeError_init

Objects/typeobject.c:2353:16
# local_traverse

Objects/typeobject.c:2575:5
# ImportError_dealloc

Python/bltinmodule.c:1434:25
# unicode_ascii_iter_next

Python/bltinmodule.c:1547:11
# gen_iternext

Python/bltinmodule.c:2979:20
# reversed_next

Python/bltinmodule.c:3002:20
# reversed_next

Python/bltinmodule.c:323:16
# gen_iternext

Python/bltinmodule.c:372:16
# gen_iternext

Python/gc.c:1126:24
# cell_clear

Python/gc.c:1408:16
# namespace_traverse

Python/gc.c:2023:11
# inst_seq_traverse
# tb_traverse

Python/gc.c:568:16
# namespace_traverse

Python/gc.c:685:20
# namespace_traverse

Python/generated_cases.c.h:1366:35
# typevar_typing_prepare_subst

Python/generated_cases.c.h:1514:35
# list_append

Python/generated_cases.c.h:2268:35
# dict_pop

Python/generated_cases.c.h:2349:35
# bytes_decode

Python/generated_cases.c.h:2420:35
# set_pop

Python/generated_cases.c.h:2488:35
# list_extend

Python/generated_cases.c.h:3628:36
# unicode_ascii_iter_next

Python/hashtable.c:385:9
# del_extensions_cache_value

Python/lock.c:330:23
# set_done

vstinner added a commit that referenced this issue Oct 5, 2024
* Add "CAST" macros.
* Rename parameters/variables "o" to "ag", "ags", "agw" or "agt"
  in some functions.
vstinner added a commit to vstinner/cpython that referenced this issue Oct 7, 2024
vstinner added a commit to vstinner/cpython that referenced this issue Oct 7, 2024
* Add "fileio_" prefix to getter functions.
* Small refactoring.
vstinner added a commit that referenced this issue Oct 7, 2024
* Add "fileio_" prefix to getter functions.
* Small refactoring.
cmaloney added a commit to cmaloney/cpython that referenced this issue Oct 7, 2024
vstinner added a commit to vstinner/cpython that referenced this issue Oct 9, 2024
vstinner added a commit to vstinner/cpython that referenced this issue Oct 9, 2024
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
topic-C-API type-bug An unexpected behavior, bug, or error
Projects
None yet
Development

No branches or pull requests

7 participants