https://github.com/python/cpython/commit/a739f8061b5456643c1a65bab9813555c2612829 commit: a739f8061b5456643c1a65bab9813555c2612829 branch: 3.14 author: Serhiy Storchaka <[email protected]> committer: serhiy-storchaka <[email protected]> date: 2026-07-20T09:23:42Z summary:
[3.14] gh-154211: Skip C-stack exhaustion tests when the C stack is huge (GH-154212) (GH-154231) (cherry picked from commit 863b31268c3160af1febcee4c79ff6ed380f328f) Co-authored-by: Claude Fable 5 <[email protected]> files: A Misc/NEWS.d/next/Tests/2026-07-20-11-30-00.gh-issue-154211.hugestack.rst M Lib/test/list_tests.py M Lib/test/mapping_tests.py M Lib/test/support/__init__.py M Lib/test/test_ast/test_ast.py M Lib/test/test_call.py M Lib/test/test_class.py M Lib/test/test_compile.py M Lib/test/test_copy.py M Lib/test/test_ctypes/test_as_parameter.py M Lib/test/test_descr.py M Lib/test/test_dict.py M Lib/test/test_dictviews.py M Lib/test/test_exception_group.py M Lib/test/test_exceptions.py M Lib/test/test_functools.py M Lib/test/test_isinstance.py M Lib/test/test_json/test_recursion.py M Lib/test/test_pyexpat.py M Lib/test/test_xml_etree.py diff --git a/Lib/test/list_tests.py b/Lib/test/list_tests.py index e76f79c274e744a..ec2aa59f2cb8728 100644 --- a/Lib/test/list_tests.py +++ b/Lib/test/list_tests.py @@ -6,7 +6,7 @@ from functools import cmp_to_key from test import seq_tests -from test.support import ALWAYS_EQ, NEVER_EQ +from test.support import ALWAYS_EQ, NEVER_EQ, skip_if_huge_c_stack from test.support import skip_emscripten_stack_overflow, skip_wasi_stack_overflow @@ -60,6 +60,7 @@ def test_repr(self): self.assertEqual(str(a2), "[0, 1, 2, [...], 3]") self.assertEqual(repr(a2), "[0, 1, 2, [...], 3]") + @skip_if_huge_c_stack(200_000) @skip_wasi_stack_overflow() @skip_emscripten_stack_overflow() def test_repr_deep(self): diff --git a/Lib/test/mapping_tests.py b/Lib/test/mapping_tests.py index 20306e1526d7b84..b95affd9f78479b 100644 --- a/Lib/test/mapping_tests.py +++ b/Lib/test/mapping_tests.py @@ -622,6 +622,7 @@ def __repr__(self): d = self._full_mapping({1: BadRepr()}) self.assertRaises(Exc, repr, d) + @support.skip_if_huge_c_stack() @support.skip_wasi_stack_overflow() @support.skip_emscripten_stack_overflow() @support.skip_if_sanitizer("requires deep stack", ub=True) diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py index c401e18247e6017..005ab19a93d941c 100644 --- a/Lib/test/support/__init__.py +++ b/Lib/test/support/__init__.py @@ -44,7 +44,7 @@ "check__all__", "skip_if_buggy_ucrt_strfptime", "check_disallow_instantiation", "check_sanitizer", "skip_if_sanitizer", "requires_limited_api", "requires_specialization", "thread_unsafe", - "skip_if_unlimited_stack_size", + "skip_if_unlimited_stack_size", "skip_if_huge_c_stack", # sys "MS_WINDOWS", "is_jython", "is_android", "is_emscripten", "is_wasi", "is_apple_mobile", "check_impl_detail", "unix_shell", "setswitchinterval", @@ -2743,6 +2743,32 @@ def exceeds_recursion_limit(): return 150_000 +def skip_if_huge_c_stack(depth=150_000): + """Skip decorator for tests which cannot overflow the C stack. + + Tests exhausting the C stack with *depth* recursive calls cannot + trigger the recursion protection if the C stack is too large (e.g. + with a large or unlimited RLIMIT_STACK), and either fail, or run + for a very long time, or crash, or consume all memory. + """ + try: + from _testinternalcapi import get_c_recursion_remaining + except ImportError: + # Fall back to checking for an unlimited stack size. + huge = False + if not (is_emscripten or is_wasi) and os.name != "nt": + import resource + soft, hard = resource.getrlimit(resource.RLIMIT_STACK) + huge = soft == hard and soft in (-1, 0xFFFF_FFFF_FFFF_FFFF) + else: + remaining = get_c_recursion_remaining() + # A negative value means integer overflow in the estimate + # (e.g. with an unlimited RLIMIT_STACK). + huge = remaining >= depth or remaining < 0 + return unittest.skipIf( + huge, f"the C stack is large enough for {depth} recursive calls") + + # Windows doesn't have os.uname() but it doesn't support s390x. is_s390x = hasattr(os, 'uname') and os.uname().machine == 's390x' skip_on_s390x = unittest.skipIf(is_s390x, 'skipped on s390x') diff --git a/Lib/test/test_ast/test_ast.py b/Lib/test/test_ast/test_ast.py index ef12ce0ce37de8e..3f607a00d2508e0 100644 --- a/Lib/test/test_ast/test_ast.py +++ b/Lib/test/test_ast/test_ast.py @@ -24,7 +24,9 @@ from test import support from test.support import os_helper -from test.support import skip_emscripten_stack_overflow, skip_wasi_stack_overflow, skip_if_unlimited_stack_size +from test.support import (skip_emscripten_stack_overflow, + skip_wasi_stack_overflow, + skip_if_unlimited_stack_size, skip_if_huge_c_stack) from test.support.ast_helper import ASTTestMixin from test.support.import_helper import ensure_lazy_imports from test.test_ast.utils import to_tuple @@ -988,7 +990,7 @@ def next(self): enum._test_simple_enum(_Precedence, _ast_unparse._Precedence) @support.cpython_only - @skip_if_unlimited_stack_size + @support.skip_if_huge_c_stack(100_000 if sys.platform == "android" else 500_000) @skip_wasi_stack_overflow() @skip_emscripten_stack_overflow() def test_ast_recursion_limit(self): @@ -1960,7 +1962,7 @@ def test_level_as_none(self): exec(code, ns) self.assertIn('sleep', ns) - @skip_if_unlimited_stack_size + @skip_if_huge_c_stack() @skip_emscripten_stack_overflow() def test_recursion_direct(self): e = ast.UnaryOp(op=ast.Not(), lineno=0, col_offset=0, operand=ast.Constant(1)) @@ -1969,7 +1971,7 @@ def test_recursion_direct(self): with support.infinite_recursion(): compile(ast.Expression(e), "<test>", "eval") - @skip_if_unlimited_stack_size + @skip_if_huge_c_stack() @skip_emscripten_stack_overflow() def test_recursion_indirect(self): e = ast.UnaryOp(op=ast.Not(), lineno=0, col_offset=0, operand=ast.Constant(1)) diff --git a/Lib/test/test_call.py b/Lib/test/test_call.py index b18f16a6efcf84a..d3af0eed893874e 100644 --- a/Lib/test/test_call.py +++ b/Lib/test/test_call.py @@ -3,7 +3,7 @@ set_recursion_limit, skip_on_s390x, skip_emscripten_stack_overflow, skip_wasi_stack_overflow, skip_if_sanitizer, - import_helper) + skip_if_huge_c_stack, import_helper) try: import _testcapi except ImportError: @@ -1062,6 +1062,7 @@ def get_sp(): @unittest.skipIf(is_wasi and Py_DEBUG, "requires deep stack") @skip_if_sanitizer("requires deep stack", thread=True) @unittest.skipIf(_testcapi is None, "requires _testcapi") + @skip_if_huge_c_stack(90_000) @skip_emscripten_stack_overflow() @skip_wasi_stack_overflow() def test_super_deep(self): diff --git a/Lib/test/test_class.py b/Lib/test/test_class.py index 30e959189d68afc..df46c0de00d60aa 100644 --- a/Lib/test/test_class.py +++ b/Lib/test/test_class.py @@ -555,6 +555,7 @@ class Custom: self.assertFalse(hasattr(o, "__call__")) self.assertFalse(hasattr(c, "__call__")) + @support.skip_if_huge_c_stack() @support.skip_emscripten_stack_overflow() @support.skip_wasi_stack_overflow() def testSFBug532646(self): diff --git a/Lib/test/test_compile.py b/Lib/test/test_compile.py index a6542b396ccfcfa..db1b4c6aa95186d 100644 --- a/Lib/test/test_compile.py +++ b/Lib/test/test_compile.py @@ -724,6 +724,7 @@ def test_yet_more_evil_still_undecodable(self): @support.cpython_only @unittest.skipIf(support.is_wasi, "exhausts limited stack on WASI") + @support.skip_if_huge_c_stack(100_000 if sys.platform == "android" else 500_000) @support.skip_emscripten_stack_overflow() def test_compiler_recursion_limit(self): # Compiler frames are small diff --git a/Lib/test/test_copy.py b/Lib/test/test_copy.py index cfef24727e8c82e..b452ddbef5ccbee 100644 --- a/Lib/test/test_copy.py +++ b/Lib/test/test_copy.py @@ -371,6 +371,7 @@ def test_deepcopy_list(self): self.assertIsNot(x, y) self.assertIsNot(x[0], y[0]) + @support.skip_if_huge_c_stack() @support.skip_emscripten_stack_overflow() @support.skip_wasi_stack_overflow() def test_deepcopy_reflexive_list(self): @@ -400,6 +401,7 @@ def test_deepcopy_tuple_of_immutables(self): y = copy.deepcopy(x) self.assertIs(x, y) + @support.skip_if_huge_c_stack() @support.skip_emscripten_stack_overflow() @support.skip_wasi_stack_overflow() def test_deepcopy_reflexive_tuple(self): @@ -419,6 +421,7 @@ def test_deepcopy_dict(self): self.assertIsNot(x, y) self.assertIsNot(x["foo"], y["foo"]) + @support.skip_if_huge_c_stack() @support.skip_emscripten_stack_overflow() @support.skip_wasi_stack_overflow() def test_deepcopy_reflexive_dict(self): @@ -579,6 +582,7 @@ def __eq__(self, other): self.assertIsNot(y, x) self.assertIsNot(y.foo, x.foo) + @support.skip_if_huge_c_stack() def test_deepcopy_reflexive_inst(self): class C: pass @@ -641,6 +645,7 @@ def __eq__(self, other): self.assertEqual(y, x) self.assertIsNot(y.foo, x.foo) + @support.skip_if_huge_c_stack() def test_reconstruct_reflexive(self): class C(object): pass diff --git a/Lib/test/test_ctypes/test_as_parameter.py b/Lib/test/test_ctypes/test_as_parameter.py index c9d728e9ae2f9cb..abbfb6efdcea55b 100644 --- a/Lib/test/test_ctypes/test_as_parameter.py +++ b/Lib/test/test_ctypes/test_as_parameter.py @@ -5,7 +5,8 @@ c_short, c_int, c_long, c_longlong, c_byte, c_wchar, c_float, c_double, ArgumentError) -from test.support import import_helper, skip_if_sanitizer, skip_emscripten_stack_overflow +from test.support import (import_helper, skip_if_sanitizer, + skip_emscripten_stack_overflow, skip_if_huge_c_stack) _ctypes_test = import_helper.import_module("_ctypes_test") @@ -193,6 +194,7 @@ class S8I(Structure): (9*2, 8*3, 7*4, 6*5, 5*6, 4*7, 3*8, 2*9)) @skip_if_sanitizer('requires deep stack', thread=True) + @skip_if_huge_c_stack() @skip_emscripten_stack_overflow() def test_recursive_as_param(self): class A: diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py index 626e05f4a085235..00e5386b1d56b98 100644 --- a/Lib/test/test_descr.py +++ b/Lib/test/test_descr.py @@ -3692,6 +3692,7 @@ def f(a): return a encoding='latin1', errors='replace') self.assertEqual(ba, b'abc\xbd?') + @support.skip_if_huge_c_stack() @support.skip_wasi_stack_overflow() @support.skip_emscripten_stack_overflow() def test_recursive_call(self): @@ -4899,6 +4900,7 @@ class Thing: # CALL_METHOD_DESCRIPTOR_O deque.append(thing, thing) + @support.skip_if_huge_c_stack() @support.skip_emscripten_stack_overflow() @support.skip_wasi_stack_overflow() def test_repr_as_str(self): diff --git a/Lib/test/test_dict.py b/Lib/test/test_dict.py index c1e64a5d99b9e95..7cc6dc7715e2fdf 100644 --- a/Lib/test/test_dict.py +++ b/Lib/test/test_dict.py @@ -678,6 +678,7 @@ def __repr__(self): d = {1: BadRepr()} self.assertRaises(Exc, repr, d) + @support.skip_if_huge_c_stack() @support.skip_wasi_stack_overflow() @support.skip_emscripten_stack_overflow() def test_repr_deep(self): diff --git a/Lib/test/test_dictviews.py b/Lib/test/test_dictviews.py index 691fc5dfb5e8ab9..9816ae6c033ec74 100644 --- a/Lib/test/test_dictviews.py +++ b/Lib/test/test_dictviews.py @@ -2,7 +2,9 @@ import copy import pickle import unittest -from test.support import skip_emscripten_stack_overflow, skip_wasi_stack_overflow, exceeds_recursion_limit +from test.support import (skip_emscripten_stack_overflow, + skip_wasi_stack_overflow, skip_if_huge_c_stack, + exceeds_recursion_limit) class DictSetTest(unittest.TestCase): @@ -277,6 +279,7 @@ def test_recursive_repr(self): # Again. self.assertIsInstance(r, str) + @skip_if_huge_c_stack() @skip_wasi_stack_overflow() @skip_emscripten_stack_overflow() def test_deeply_nested_repr(self): diff --git a/Lib/test/test_exception_group.py b/Lib/test/test_exception_group.py index db6ff9d33b44aa9..7d690ca59738ebb 100644 --- a/Lib/test/test_exception_group.py +++ b/Lib/test/test_exception_group.py @@ -1,7 +1,9 @@ import collections import types import unittest -from test.support import skip_emscripten_stack_overflow, skip_wasi_stack_overflow, exceeds_recursion_limit +from test.support import (skip_emscripten_stack_overflow, + skip_wasi_stack_overflow, skip_if_huge_c_stack, + exceeds_recursion_limit) class TestExceptionGroupTypeHierarchy(unittest.TestCase): def test_exception_group_types(self): @@ -535,6 +537,7 @@ def make_deep_eg(self): e = ExceptionGroup('eg', [e]) return e + @skip_if_huge_c_stack() @skip_emscripten_stack_overflow() @skip_wasi_stack_overflow() def test_deep_split(self): @@ -542,6 +545,7 @@ def test_deep_split(self): with self.assertRaises(RecursionError): e.split(TypeError) + @skip_if_huge_c_stack() @skip_emscripten_stack_overflow() @skip_wasi_stack_overflow() def test_deep_subgroup(self): diff --git a/Lib/test/test_exceptions.py b/Lib/test/test_exceptions.py index 3a0f94e44f292f1..e79e52911f66aba 100644 --- a/Lib/test/test_exceptions.py +++ b/Lib/test/test_exceptions.py @@ -1509,6 +1509,7 @@ def gen(): @cpython_only @unittest.skipIf(_testcapi is None, "requires _testcapi") @force_not_colorized + @support.skip_if_huge_c_stack() def test_recursion_normalizing_infinite_exception(self): # Issue #30697. Test that a RecursionError is raised when # maximum recursion depth has been exceeded when creating diff --git a/Lib/test/test_functools.py b/Lib/test/test_functools.py index 16adb8dad7d8bc3..6531bd2bca33c70 100644 --- a/Lib/test/test_functools.py +++ b/Lib/test/test_functools.py @@ -438,7 +438,7 @@ def test_setstate_subclasses(self): self.assertIs(type(r[0]), tuple) @support.skip_if_sanitizer("thread sanitizer crashes in __tsan::FuncEntry", thread=True) - @support.skip_if_unlimited_stack_size + @support.skip_if_huge_c_stack() @support.skip_emscripten_stack_overflow() def test_recursive_pickle(self): with replaced_module('functools', self.module): diff --git a/Lib/test/test_isinstance.py b/Lib/test/test_isinstance.py index d97535ba46e677f..16d879a3831bc65 100644 --- a/Lib/test/test_isinstance.py +++ b/Lib/test/test_isinstance.py @@ -263,6 +263,7 @@ def test_subclass_tuple(self): self.assertEqual(True, issubclass(int, (int, (float, int)))) self.assertEqual(True, issubclass(str, (str, (Child, str)))) + @support.skip_if_huge_c_stack() @support.skip_wasi_stack_overflow() @support.skip_emscripten_stack_overflow() def test_subclass_recursion_limit(self): @@ -270,6 +271,7 @@ def test_subclass_recursion_limit(self): # blown self.assertRaises(RecursionError, blowstack, issubclass, str, str) + @support.skip_if_huge_c_stack() @support.skip_wasi_stack_overflow() @support.skip_emscripten_stack_overflow() def test_isinstance_recursion_limit(self): @@ -317,7 +319,7 @@ def __bases__(self): self.assertRaises(RecursionError, issubclass, int, X()) self.assertRaises(RecursionError, isinstance, 1, X()) - @support.skip_if_unlimited_stack_size + @support.skip_if_huge_c_stack() @support.skip_emscripten_stack_overflow() @support.skip_wasi_stack_overflow() def test_infinite_recursion_via_bases_tuple(self): @@ -329,7 +331,7 @@ def __getattr__(self, attr): with self.assertRaises(RecursionError): issubclass(Failure(), int) - @support.skip_if_unlimited_stack_size + @support.skip_if_huge_c_stack() @support.skip_emscripten_stack_overflow() @support.skip_wasi_stack_overflow() def test_infinite_cycle_in_bases(self): diff --git a/Lib/test/test_json/test_recursion.py b/Lib/test/test_json/test_recursion.py index d732fc80cf1cf30..cbae9fbb4d624ba 100644 --- a/Lib/test/test_json/test_recursion.py +++ b/Lib/test/test_json/test_recursion.py @@ -69,7 +69,7 @@ def default(self, o): @support.skip_if_pgo_task # fails during PGO training w/ some stack sizes - @support.skip_if_unlimited_stack_size + @support.skip_if_huge_c_stack(500_000) @support.skip_emscripten_stack_overflow() @support.skip_wasi_stack_overflow() def test_highly_nested_objects_decoding(self): @@ -102,7 +102,7 @@ def test_highly_nested_objects_encoding(self): with support.infinite_recursion(5000): self.dumps(d) - @support.skip_if_unlimited_stack_size + @support.skip_if_huge_c_stack() @support.skip_emscripten_stack_overflow() @support.skip_wasi_stack_overflow() def test_endless_recursion(self): diff --git a/Lib/test/test_pyexpat.py b/Lib/test/test_pyexpat.py index 37dbb313b014e85..10e2e5f79908b0b 100644 --- a/Lib/test/test_pyexpat.py +++ b/Lib/test/test_pyexpat.py @@ -815,7 +815,7 @@ def test_trigger_leak(self): parser.ElementDeclHandler = lambda _1, _2: None self.assertRaises(TypeError, parser.Parse, data, True) - @support.skip_if_unlimited_stack_size + @support.skip_if_huge_c_stack(800_000) @support.skip_emscripten_stack_overflow() @support.skip_wasi_stack_overflow() def test_deeply_nested_content_model(self): diff --git a/Lib/test/test_xml_etree.py b/Lib/test/test_xml_etree.py index 8c693bfbdb39d92..e268ed7f1ebef3d 100644 --- a/Lib/test/test_xml_etree.py +++ b/Lib/test/test_xml_etree.py @@ -3123,7 +3123,7 @@ def __deepcopy__(self, memo): self.assertEqual([c.tag for c in children[3:]], [a.tag, b.tag, a.tag, b.tag]) - @support.skip_if_unlimited_stack_size + @support.skip_if_huge_c_stack(500_000) @support.skip_emscripten_stack_overflow() @support.skip_wasi_stack_overflow() def test_deeply_nested_deepcopy(self): diff --git a/Misc/NEWS.d/next/Tests/2026-07-20-11-30-00.gh-issue-154211.hugestack.rst b/Misc/NEWS.d/next/Tests/2026-07-20-11-30-00.gh-issue-154211.hugestack.rst new file mode 100644 index 000000000000000..8030db869c7ba6e --- /dev/null +++ b/Misc/NEWS.d/next/Tests/2026-07-20-11-30-00.gh-issue-154211.hugestack.rst @@ -0,0 +1,3 @@ +Add ``test.support.skip_if_huge_c_stack()`` and use it to skip tests +that exhaust the C stack if the stack limit is very large +(e.g. on DragonFly BSD or with ``ulimit -s unlimited``). _______________________________________________ Python-checkins mailing list -- [email protected] To unsubscribe send an email to [email protected] https://mail.python.org/mailman3//lists/python-checkins.python.org Member address: [email protected]
