[Python-checkins] [3.11] gh-90473: Reduce recursion limit on WASI even further (GH-94333) (GH-94334)

[tiran]

https://github.com/python/cpython/commit/56f5f904968b3796dad942e87e971e7b87c571f3
commit: 56f5f904968b3796dad942e87e971e7b87c571f3
branch: 3.11
author: Christian Heimes <christian at python.org>
committer: tiran <christian at python.org>
date: 2022-06-27T18:33:01+02:00
summary:

[3.11] gh-90473: Reduce recursion limit on WASI even further (GH-94333) (GH-94334)

Co-authored-by: Christian Heimes <christian at python.org>

files:
M Include/internal/pycore_ceval.h
M Lib/test/test_tomllib/test_misc.py

diff --git a/Include/internal/pycore_ceval.h b/Include/internal/pycore_ceval.h
index d969a5e6eb99b..8d18d200aa4bf 100644
--- a/Include/internal/pycore_ceval.h
+++ b/Include/internal/pycore_ceval.h
@@ -12,11 +12,12 @@ extern "C" {
 struct pyruntimestate;
 struct _ceval_runtime_state;
 
-/* WASI has limited call stack. wasmtime 0.36 can handle sufficient amount of
-   C stack frames for little more than 750 recursions. */
+/* WASI has limited call stack. Python's recursion limit depends on code
+   layout, optimization, and WASI runtime. Wasmtime can handle about 700-750
+   recursions, sometimes less. 600 is a more conservative limit. */
 #ifndef Py_DEFAULT_RECURSION_LIMIT
 #  ifdef __wasi__
-#    define Py_DEFAULT_RECURSION_LIMIT 750
+#    define Py_DEFAULT_RECURSION_LIMIT 600
 #  else
 #    define Py_DEFAULT_RECURSION_LIMIT 1000
 #  endif
diff --git a/Lib/test/test_tomllib/test_misc.py b/Lib/test/test_tomllib/test_misc.py
index 378db58f25594..a477a219fd9eb 100644
--- a/Lib/test/test_tomllib/test_misc.py
+++ b/Lib/test/test_tomllib/test_misc.py
@@ -92,8 +92,8 @@ def test_deepcopy(self):
         self.assertEqual(obj_copy, expected_obj)
 
     def test_inline_array_recursion_limit(self):
-        # 470 with default recursion limit
-        nest_count = int(sys.getrecursionlimit() * 0.47)
+        # 465 with default recursion limit
+        nest_count = int(sys.getrecursionlimit() * 0.465)
         recursive_array_toml = "arr = " + nest_count * "[" + nest_count * "]"
         tomllib.loads(recursive_array_toml)