https://github.com/python/cpython/commit/17b73ab99ef12f89d41acec7500a244e68b1aaa4
commit: 17b73ab99ef12f89d41acec7500a244e68b1aaa4
branch: main
author: Mark Shannon <[email protected]>
committer: markshannon <[email protected]>
date: 2024-01-16T09:32:01Z
summary:
GH-113655: Lower the C recursion limit on various platforms (GH-113944)
files:
A Misc/NEWS.d/next/Core and
Builtins/2024-01-11-01-28-25.gh-issue-113655.Mfioxp.rst
M Include/cpython/pystate.h
M Lib/test/support/__init__.py
M Lib/test/test_ast.py
M Lib/test/test_compile.py
M Lib/test/test_functools.py
M Lib/test/test_sys_settrace.py
M Parser/asdl_c.py
M Python/Python-ast.c
M Python/ast.c
M Python/ast_opt.c
M Python/symtable.c
M Python/traceback.c
diff --git a/Include/cpython/pystate.h b/Include/cpython/pystate.h
index ed7dd829d4b6f0..10913943c1140d 100644
--- a/Include/cpython/pystate.h
+++ b/Include/cpython/pystate.h
@@ -224,10 +224,14 @@ struct _ts {
// recursions, sometimes less. 500 is a more conservative limit.
# define Py_C_RECURSION_LIMIT 500
#elif defined(__s390x__)
-# define Py_C_RECURSION_LIMIT 1200
+# define Py_C_RECURSION_LIMIT 800
+#elif defined(_WIN32)
+# define Py_C_RECURSION_LIMIT 4000
+#elif defined(_Py_ADDRESS_SANITIZER)
+# define Py_C_RECURSION_LIMIT 4000
#else
// This value is duplicated in Lib/test/support/__init__.py
-# define Py_C_RECURSION_LIMIT 8000
+# define Py_C_RECURSION_LIMIT 10000
#endif
diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py
index e5fb725a30b5b8..8344dd1849c61d 100644
--- a/Lib/test/support/__init__.py
+++ b/Lib/test/support/__init__.py
@@ -2377,7 +2377,10 @@ def _get_c_recursion_limit():
return _testcapi.Py_C_RECURSION_LIMIT
except (ImportError, AttributeError):
# Originally taken from Include/cpython/pystate.h .
- return 8000
+ if sys.platform == 'win32':
+ return 4000
+ else:
+ return 10000
# The default C recursion limit.
Py_C_RECURSION_LIMIT = _get_c_recursion_limit()
diff --git a/Lib/test/test_ast.py b/Lib/test/test_ast.py
index 64fcb02309de77..3789ac22e3899c 100644
--- a/Lib/test/test_ast.py
+++ b/Lib/test/test_ast.py
@@ -1126,7 +1126,7 @@ def next(self):
def test_ast_recursion_limit(self):
fail_depth = support.EXCEEDS_RECURSION_LIMIT
crash_depth = 100_000
- success_depth = 1200
+ success_depth = int(support.Py_C_RECURSION_LIMIT * 0.8)
if _testinternalcapi is not None:
remaining = _testinternalcapi.get_c_recursion_remaining()
success_depth = min(success_depth, remaining)
diff --git a/Lib/test/test_compile.py b/Lib/test/test_compile.py
index 50629b22822245..9c36f053314f9f 100644
--- a/Lib/test/test_compile.py
+++ b/Lib/test/test_compile.py
@@ -623,12 +623,10 @@ def test_yet_more_evil_still_undecodable(self):
@support.cpython_only
@unittest.skipIf(support.is_wasi, "exhausts limited stack on WASI")
def test_compiler_recursion_limit(self):
- # Expected limit is Py_C_RECURSION_LIMIT * 2
- # Duplicating the limit here is a little ugly.
- # Perhaps it should be exposed somewhere...
- fail_depth = Py_C_RECURSION_LIMIT * 2 + 1
+ # Expected limit is Py_C_RECURSION_LIMIT
+ fail_depth = Py_C_RECURSION_LIMIT + 1
crash_depth = Py_C_RECURSION_LIMIT * 100
- success_depth = int(Py_C_RECURSION_LIMIT * 1.8)
+ success_depth = int(Py_C_RECURSION_LIMIT * 0.8)
def check_limit(prefix, repeated, mode="single"):
expect_ok = prefix + repeated * success_depth
diff --git a/Lib/test/test_functools.py b/Lib/test/test_functools.py
index 0ef45d3c670e85..7c66b906d308ba 100644
--- a/Lib/test/test_functools.py
+++ b/Lib/test/test_functools.py
@@ -1875,8 +1875,14 @@ def fib(n):
return fib(n-1) + fib(n-2)
if not support.Py_DEBUG:
+ depth = support.Py_C_RECURSION_LIMIT*2//7
with support.infinite_recursion():
- fib(2500)
+ fib(depth)
+ if self.module == c_functools:
+ fib.cache_clear()
+ with support.infinite_recursion():
+ with self.assertRaises(RecursionError):
+ fib(10000)
@py_functools.lru_cache()
diff --git a/Lib/test/test_sys_settrace.py b/Lib/test/test_sys_settrace.py
index fc5ca72236b1fb..ae6e192a7ab6ef 100644
--- a/Lib/test/test_sys_settrace.py
+++ b/Lib/test/test_sys_settrace.py
@@ -3037,10 +3037,8 @@ def test_trace_unpack_long_sequence(self):
self.assertEqual(counts, {'call': 1, 'line': 301, 'return': 1})
def test_trace_lots_of_globals(self):
- count = 1000
- if _testinternalcapi is not None:
- remaining = _testinternalcapi.get_c_recursion_remaining()
- count = min(count, remaining)
+
+ count = min(1000, int(support.Py_C_RECURSION_LIMIT * 0.8))
code = """if 1:
def f():
diff --git a/Misc/NEWS.d/next/Core and
Builtins/2024-01-11-01-28-25.gh-issue-113655.Mfioxp.rst b/Misc/NEWS.d/next/Core
and Builtins/2024-01-11-01-28-25.gh-issue-113655.Mfioxp.rst
new file mode 100644
index 00000000000000..30f1b0a76612db
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and
Builtins/2024-01-11-01-28-25.gh-issue-113655.Mfioxp.rst
@@ -0,0 +1,3 @@
+Set the C recursion limit to 4000 on Windows, and 10000 on Linux/OSX. This
+seems to be near the sweet spot to maintain safety, but not compromise
+backwards compatibility.
diff --git a/Parser/asdl_c.py b/Parser/asdl_c.py
index 4bb337349748cf..ce92672bf00776 100755
--- a/Parser/asdl_c.py
+++ b/Parser/asdl_c.py
@@ -1388,15 +1388,14 @@ class PartingShots(StaticVisitor):
int starting_recursion_depth;
/* Be careful here to prevent overflow. */
- int COMPILER_STACK_FRAME_SCALE = 2;
PyThreadState *tstate = _PyThreadState_GET();
if (!tstate) {
return NULL;
}
struct validator vstate;
- vstate.recursion_limit = Py_C_RECURSION_LIMIT * COMPILER_STACK_FRAME_SCALE;
+ vstate.recursion_limit = Py_C_RECURSION_LIMIT;
int recursion_depth = Py_C_RECURSION_LIMIT - tstate->c_recursion_remaining;
- starting_recursion_depth = recursion_depth * COMPILER_STACK_FRAME_SCALE;
+ starting_recursion_depth = recursion_depth;
vstate.recursion_depth = starting_recursion_depth;
PyObject *result = ast2obj_mod(state, &vstate, t);
diff --git a/Python/Python-ast.c b/Python/Python-ast.c
index 699e1c157c591c..d77e986ba067a3 100644
--- a/Python/Python-ast.c
+++ b/Python/Python-ast.c
@@ -13149,15 +13149,14 @@ PyObject* PyAST_mod2obj(mod_ty t)
int starting_recursion_depth;
/* Be careful here to prevent overflow. */
- int COMPILER_STACK_FRAME_SCALE = 2;
PyThreadState *tstate = _PyThreadState_GET();
if (!tstate) {
return NULL;
}
struct validator vstate;
- vstate.recursion_limit = Py_C_RECURSION_LIMIT * COMPILER_STACK_FRAME_SCALE;
+ vstate.recursion_limit = Py_C_RECURSION_LIMIT;
int recursion_depth = Py_C_RECURSION_LIMIT - tstate->c_recursion_remaining;
- starting_recursion_depth = recursion_depth * COMPILER_STACK_FRAME_SCALE;
+ starting_recursion_depth = recursion_depth;
vstate.recursion_depth = starting_recursion_depth;
PyObject *result = ast2obj_mod(state, &vstate, t);
diff --git a/Python/ast.c b/Python/ast.c
index 5f46d4149c2ed0..71b09d889f17c1 100644
--- a/Python/ast.c
+++ b/Python/ast.c
@@ -1037,10 +1037,6 @@ validate_type_params(struct validator *state,
asdl_type_param_seq *tps)
return 1;
}
-
-/* See comments in symtable.c. */
-#define COMPILER_STACK_FRAME_SCALE 2
-
int
_PyAST_Validate(mod_ty mod)
{
@@ -1057,9 +1053,9 @@ _PyAST_Validate(mod_ty mod)
}
/* Be careful here to prevent overflow. */
int recursion_depth = Py_C_RECURSION_LIMIT - tstate->c_recursion_remaining;
- starting_recursion_depth = recursion_depth * COMPILER_STACK_FRAME_SCALE;
+ starting_recursion_depth = recursion_depth;
state.recursion_depth = starting_recursion_depth;
- state.recursion_limit = Py_C_RECURSION_LIMIT * COMPILER_STACK_FRAME_SCALE;
+ state.recursion_limit = Py_C_RECURSION_LIMIT;
switch (mod->kind) {
case Module_kind:
diff --git a/Python/ast_opt.c b/Python/ast_opt.c
index 04d7ae6eaafbc0..41e906c66e8eec 100644
--- a/Python/ast_opt.c
+++ b/Python/ast_opt.c
@@ -1100,9 +1100,6 @@ astfold_type_param(type_param_ty node_, PyArena *ctx_,
_PyASTOptimizeState *stat
#undef CALL_OPT
#undef CALL_SEQ
-/* See comments in symtable.c. */
-#define COMPILER_STACK_FRAME_SCALE 2
-
int
_PyAST_Optimize(mod_ty mod, PyArena *arena, int optimize, int ff_features)
{
@@ -1120,9 +1117,9 @@ _PyAST_Optimize(mod_ty mod, PyArena *arena, int optimize,
int ff_features)
}
/* Be careful here to prevent overflow. */
int recursion_depth = Py_C_RECURSION_LIMIT - tstate->c_recursion_remaining;
- starting_recursion_depth = recursion_depth * COMPILER_STACK_FRAME_SCALE;
+ starting_recursion_depth = recursion_depth;
state.recursion_depth = starting_recursion_depth;
- state.recursion_limit = Py_C_RECURSION_LIMIT * COMPILER_STACK_FRAME_SCALE;
+ state.recursion_limit = Py_C_RECURSION_LIMIT;
int ret = astfold_mod(mod, arena, &state);
assert(ret || PyErr_Occurred());
diff --git a/Python/symtable.c b/Python/symtable.c
index 83137b491f282c..743029956e32fa 100644
--- a/Python/symtable.c
+++ b/Python/symtable.c
@@ -386,11 +386,6 @@ symtable_new(void)
return NULL;
}
-/* Using a scaling factor means this should automatically adjust when
- the recursion limit is adjusted for small or large C stack allocations.
-*/
-#define COMPILER_STACK_FRAME_SCALE 2
-
struct symtable *
_PySymtable_Build(mod_ty mod, PyObject *filename, PyFutureFeatures *future)
{
@@ -417,9 +412,9 @@ _PySymtable_Build(mod_ty mod, PyObject *filename,
PyFutureFeatures *future)
}
/* Be careful here to prevent overflow. */
int recursion_depth = Py_C_RECURSION_LIMIT - tstate->c_recursion_remaining;
- starting_recursion_depth = recursion_depth * COMPILER_STACK_FRAME_SCALE;
+ starting_recursion_depth = recursion_depth;
st->recursion_depth = starting_recursion_depth;
- st->recursion_limit = Py_C_RECURSION_LIMIT * COMPILER_STACK_FRAME_SCALE;
+ st->recursion_limit = Py_C_RECURSION_LIMIT;
/* Make the initial symbol information gathering pass */
if (!symtable_enter_block(st, &_Py_ID(top), ModuleBlock, (void *)mod, 0,
0, 0, 0)) {
diff --git a/Python/traceback.c b/Python/traceback.c
index abd429ac6c1f71..7a188e56c939c0 100644
--- a/Python/traceback.c
+++ b/Python/traceback.c
@@ -965,7 +965,11 @@ dump_traceback(int fd, PyThreadState *tstate, int
write_header)
unsigned int depth = 0;
while (1) {
if (MAX_FRAME_DEPTH <= depth) {
- PUTS(fd, " ...\n");
+ if (MAX_FRAME_DEPTH < depth) {
+ PUTS(fd, "plus ");
+ _Py_DumpDecimal(fd, depth);
+ PUTS(fd, " frames\n");
+ }
break;
}
dump_frame(fd, frame);
_______________________________________________
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]
