Description

sobolevn

opened on Jun 9, 2026

Issue body actions

Crash report

1. remove_unused_consts in Python/flowgraph.c

When PyMem_Malloc(nconsts * sizeof(Py_ssize_t)); fails, we need to set an exception.

cpython/Python/flowgraph.c

Lines 3267 to 3283 in 29a920e

	static int
	remove_unused_consts(basicblock *entryblock, PyObject *consts)
	{
	assert(PyList_CheckExact(consts));
	Py_ssize_t nconsts = PyList_GET_SIZE(consts);
	if (nconsts == 0) {
	return SUCCESS; /* nothing to do */
	}
	Py_ssize_t *index_map = NULL;
	Py_ssize_t *reverse_index_map = NULL;
	int err = ERROR;
	index_map = PyMem_Malloc(nconsts * sizeof(Py_ssize_t));
	if (index_map == NULL) {
	goto end;
	}

2. gethandlelist and getattributelist in _winapi.c

This place misses it:

cpython/Modules/_winapi.c

Lines 1196 to 1198 in 9fdbade

	ret = PyMem_Malloc(*size);
	if (ret == NULL)
	goto cleanup;

All other error paths set exceptions, except this if:

cpython/Modules/_winapi.c

Lines 1278 to 1282 in 9fdbade

	attribute_list->attribute_list = PyMem_Malloc(attribute_list_size);
	if (attribute_list->attribute_list == NULL) {
	ret = -1;
	goto cleanup;
	}

3. _channelends_new in Modules/_interpchannelsmodule.c

cpython/Modules/_interpchannelsmodule.c

Lines 920 to 926 in 3ca93ab

	static _channelends *
	_channelends_new(void)
	{
	_channelends *ends = GLOBAL_MALLOC(_channelends);
	if (ends== NULL) {
	return NULL;
	}

Later we check for errors in handle_channel_error, it requires either setting err to non -1 or to set Python exception. Both are false, it fails with the assertion failure.

Linked PRs

• gh-151126: Fix missing PyErr_NoMemory() in remove_unused_consts #151127
• [3.15] gh-151126: Fix missing PyErr_NoMemory() in remove_unused_consts (GH-151127) #151134
• [3.14] gh-151126: Fix missing PyErr_NoMemory() in remove_unused_consts (GH-151127) #151135
• [3.13] gh-151126: Fix missing PyErr_NoMemory() in remove_unused_consts (GH-151127) #151136
• gh-151126: Add PyErr_NoMemory() in strong_cache_node_new #151137
• gh-151126: Add missing PyErr_NoMemory in _winapi module #151154
• [3.15] gh-151126: Add missing PyErr_NoMemory in _winapi module (GH-151154) #151180
• [3.14] gh-151126: Add missing PyErr_NoMemory in _winapi module (GH-151154) #151181
• [3.13] gh-151126: Add missing PyErr_NoMemory in _winapi module (GH-151154) #151182
• gh-151126: Fix missing memory errors in _interpchannelsmodule.c #151239
• [3.15] gh-151126: Fix missing memory errors in _interpchannelsmodule.c (GH-151239) #151265
• [3.13] gh-151126: Fix missing memory errors in _interpchannelsmodule.c (GH-151239) #151266
• [3.14] gh-151126: Fix missing memory errors in _interpchannelsmodule.c (GH-151239) #151336
• [3.13] gh-151126: Fix missing memory errors in _interpchannelsmodule.c (GH-151239) #151338
• gh-151126: Fix missing memory error in os._path_splitroot #151339
• [3.15] gh-151126: Fix missing memory error in os._path_splitroot (GH-151339) #151360
• [3.14] gh-151126: Fix missing memory error in os._path_splitroot (GH-151339) #151361
• [3.13] gh-151126: Fix missing memory error in os._path_splitroot (GH-151339) #151362
• gh-151126: Fix crash on unset memory error in ctypes.get_errno #151382
• [3.15] gh-151126: Fix crash on unset memory error in ctypes.get_errno (GH-151382) #151398
• [3.14] gh-151126: Fix crash on unset memory error in ctypes.get_errno (GH-151382) #151399
• [3.13] gh-151126: Fix crash on unset memory error in ctypes.get_errno (GH-151382) #151400
• gh-151126: Fix missing PyErr_NoMemory in fileutils.c #151580
• gh-151126: Fix missing PyErr_NoMemory in typeobject.c #151582
• gh-151126: Add missing PyErr_NoMemory in _winapi.c #151588
• gh-151126: Fix missing PyErr_NoMemory in getpath.c #151590
• gh-151126:Fix missing memory errors in _interpretersmodule.c #151624
• gh-151126: Fix missing memory errors in _interpqueuesmodule.c #151639
• [3.13] gh-151126: Add missing PyErr_NoMemory() in type_from_slots_or_spec (GH-151582) #152014
• [3.14] gh-151126: Add missing PyErr_NoMemory() in type_from_slots_or_spec (GH-151582) #152015
• [3.15] gh-151126: Add missing PyErr_NoMemory() in type_from_slots_or_spec (GH-151582) #152016
• [3.15] gh-151126: Fix missing memory errors in _interpretersmodule.c (GH-151624) #152169
• [3.14] gh-151126: Fix missing memory errors in _interpretersmodule.c (GH-151624) #152170
• gh-151126: Fix missing PyErr_NoMemory in testinternalcapi.c #152177
• [3.15] gh-151126: Fix missing PyErr_NoMemory in testinternalcapi.c (GH-152177) #152179
• [3.14] gh-151126: Fix missing PyErr_NoMemory in testinternalcapi.c (GH-152177) #152180
• [3.13] gh-151126: Fix missing PyErr_NoMemory in testinternalcapi.c (GH-152177) #152181
• [3.15] gh-151126: Add missing PyErr_NoMemory in _winapi.c (GH-151588) #152182
• [3.14] gh-151126: Add missing PyErr_NoMemory in _winapi.c (GH-151588) #152183
• [3.13] gh-151126: Add missing PyErr_NoMemory in _winapi.c (GH-151588) #152184
• gh-151126: Sets missing exceptions in tkinter and socket modules initializations #152418
• [3.15] gh-151126: Sets missing exceptions in tkinter and socket modules initializations (GH-152418) #152420
• [3.14] gh-151126: Sets missing exceptions in tkinter and socket modules initializations (GH-152418) #152421
• [3.13] gh-151126: Sets missing exceptions in tkinter and socket modules initializations (GH-152418) #152422
• gh-151126: Fix a possible crash during the startup with no memory under Py_STACKREF_DEBUG #152478
• [3.15] gh-151126: Fix a possible crash during the startup with no memory under Py_STACKREF_DEBUG (GH-152478) #152677
• [3.14] gh-151126: Fix a possible crash during the startup with no memory under Py_STACKREF_DEBUG (GH-152478) #152678
• gh-151126: Fix PyErr_NoMemory errors in _ctypes.c  #152720
• gh-151126: Set MemoryError in test C API allocation failures #153215
• [3.13] gh-151126: Fix PyErr_NoMemory errors in _ctypes.c (GH-152720) #153708
• [3.14] gh-151126: Fix PyErr_NoMemory errors in _ctypes.c (GH-152720) #153709
• [3.15] gh-151126: Fix PyErr_NoMemory errors in _ctypes.c (GH-152720) #153710
• [3.13] gh-151126: Fix missing memory errors in _interpretersmodule.c  #153765
• gh-151126: set MemoryError on allocation failure in CJK codec macros #156292
• gh-151126: Check strdup result in readline on_completion #156299
• gh-151126: set MemoryError on alloc failure in _PyXIData_InitWithSize #156301
• [3.14] gh-151126: Set MemoryError on allocation failure in CJK codec macros (GH-156292) #160673
• [3.15] gh-151126: Set MemoryError on allocation failure in CJK codec macros (GH-156292) #160674
• [3.15] gh-151126: set MemoryError on alloc failure in _PyXIData_InitWithSize (GH-156301) #161905
• [3.14] gh-151126: set MemoryError on alloc failure in _PyXIData_InitWithSize (GH-156301) #161906

Activity

1. sobolevn

   self-assigned this

   on Jun 9, 2026
2. sobolevn

   added

   interpreter-core(Objects, Python, Grammar, and Parser dirs)(Objects, Python, Grammar, and Parser dirs)

   type-crashA hard crash of the interpreter, possibly with a core dumpA hard crash of the interpreter, possibly with a core dump

   on Jun 9, 2026
3. sobolevn commented on Jun 9, 2026

   

   sobolevn

   on Jun 9, 2026

   MemberAuthor

   More actions

   Well, actually a lot of places have the same problem. I will turn this issue into a meta one and will 1 PR per module, so it would be easier to review / backport.

   Reacted by Victor Stinner and Arseniy Terekhin
4. sobolevn

   changed the title [-]`remove_unused_consts` is missing `PyErr_NoMemory()` call[/-] [+]Many places have missing `PyErr_NoMemory()` call after failing memory allocation[/+] on Jun 9, 2026
5. StanFromIreland

   added this to Date and time issues 🕰️on Jun 9, 2026
6. serhiy-storchaka commented on Jun 9, 2026

   

   serhiy-storchaka

   on Jun 9, 2026

   Member

   More actions

   This is probably a new code. Such errors were fixed in old code years ago.
7. sobolevn

   added 8 commits that reference this issue on Jun 9, 2026

   gh-151126: Fix missing `PyErr_NoMemory()` in `remove_unused_consts` (#…

   3186547

   pythongh-151126: Add `PyErr_NoMemory()` in `strong_cache_node_new`

   65eebcf

   [3.13] gh-151126: Fix missing `PyErr_NoMemory()` in `remove_unused_co…

   140af0f

   [3.15] gh-151126: Fix missing `PyErr_NoMemory()` in `remove_unused_co…

   8a2bf2a

   [3.14] gh-151126: Fix missing `PyErr_NoMemory()` in `remove_unused_co…

   5c6402e

   gh-151126: Add missing `PyErr_NoMemory` in `_winapi` module (#151154)

   8d94fa7

   [3.14] gh-151126: Add missing `PyErr_NoMemory` in `_winapi` module (G…

   a33c6a1

   [3.13] gh-151126: Add missing `PyErr_NoMemory` in `_winapi` module (G…

   0488451
8. 44 remaining items
9. pyctrl

   added a commit that references this issue on Jul 5, 2026

   pythongh-151126: Add missing `PyErr_NoMemory()` in `type_from_slots_o…

   0b25972
10. kumaraditya303

    added a commit that references this issue on Jul 14, 2026

    gh-151126: Fix `PyErr_NoMemory` errors in `_ctypes.c` (#152720)

    d807210
11. sobolevn

    added a commit that references this issue on Jul 15, 2026

    [3.13] gh-151126: Fix missing memory errors in `_interpretersmodule.c` (

    8010bf0
12. Yhg1s

    added a commit that references this issue on Aug 4, 2026

    [3.13] gh-151126: Fix `PyErr_NoMemory` errors in `_ctypes.c` (GH-152720…

    3c431d5
13. KowalskiThomas

    added 3 commits that reference this issue on Aug 23, 2026

    pythongh-151126: Set MemoryError on alloc failure in CJK codec macros

    6ae41c8

    pythongh-151126: Check strdup result in readline on_completion

    7c08f01

    pythongh-151126: Set MemoryError on alloc failure in _PyXIData_InitWi…

    8cf9517
14. encukou

    added a commit that references this issue on Oct 9, 2026

    [3.15] gh-151126: Fix `PyErr_NoMemory` errors in `_ctypes.c` (GH-152720…

    bb5ff8c
15. StanFromIreland

    added 3 commits that reference this issue on Oct 25, 2026

    gh-151126: Set `MemoryError` on allocation failure in CJK codec macros (

    d441a11

    [3.14] gh-151126: Set `MemoryError` on allocation failure in CJK code…

    a5892db

    [3.15] gh-151126: Set `MemoryError` on allocation failure in CJK code…

    c6e7431
16. sobolevn

    added a commit that references this issue on Nov 11, 2026

    [3.14] gh-151126: Fix `PyErr_NoMemory` errors in `_ctypes.c` (GH-152720…

    0df6b24
17. cmaloney

    added 3 commits that reference this issue on Nov 12, 2026

    gh-151126: set `MemoryError` on alloc failure in `_PyXIData_InitWithS…

    a6018c5

    [3.15] gh-151126: set `MemoryError` on alloc failure in `_PyXIData_In…

    ef6437e

    [3.14] gh-151126: set `MemoryError` on alloc failure in `_PyXIData_In…

    5dedab8

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