GH-113655: Use PyOS_CheckStack on those platforms that support it

Include/cpython/pystate.h

@@ -214,20 +214,39 @@ struct _ts {
 
 };
 
+#if defined(__has_feature)  /* Clang */
+#  if __has_feature(address_sanitizer) /* is ASAN enabled? */
+#    define HAS_ASAN 1
+#  endif
+#endif
+
 #ifdef Py_DEBUG
    // A debug build is likely built with low optimization level which implies
    // higher stack memory usage than a release build: use a lower limit.
-#  define Py_C_RECURSION_LIMIT 500
+
+#  if defined(USE_STACKCHECK)
+#    define Py_C_RECURSION_LIMIT 300
+#  else
+#    define Py_C_RECURSION_LIMIT 500
+#  endif
 #elif defined(__wasi__)
    // WASI has limited call stack. Python's recursion limit depends on code
    // layout, optimization, and WASI runtime. Wasmtime can handle about 700
    // recursions, sometimes less. 500 is a more conservative limit.
 #  define Py_C_RECURSION_LIMIT 500
 #elif defined(__s390x__)
 #  define Py_C_RECURSION_LIMIT 1200
+#elif defined(USE_STACKCHECK)
+#  define Py_C_RECURSION_LIMIT 4000
+#elif defined (HAS_ASAN)
+#  define Py_C_RECURSION_LIMIT 7000
 #else
    // This value is duplicated in Lib/test/support/__init__.py
-#  define Py_C_RECURSION_LIMIT 8000
+#  define Py_C_RECURSION_LIMIT 10000
+#endif
+
+#ifdef HAS_ASAN
+#  undef HAS_ASAN
 #endif
 
 

Include/internal/pycore_ceval.h

@@ -135,18 +135,9 @@ extern void _PyEval_DeactivateOpCache(void);
 
 /* --- _Py_EnterRecursiveCall() ----------------------------------------- */
 
-#ifdef USE_STACKCHECK
-/* With USE_STACKCHECK macro defined, trigger stack checks in
-   _Py_CheckRecursiveCall() on every 64th call to _Py_EnterRecursiveCall. */
-static inline int _Py_MakeRecCheck(PyThreadState *tstate)  {
-    return (tstate->c_recursion_remaining-- <= 0
-            || (tstate->c_recursion_remaining & 63) == 0);
-}
-#else
 static inline int _Py_MakeRecCheck(PyThreadState *tstate) {
     return tstate->c_recursion_remaining-- <= 0;
 }
-#endif
 
 // Export for '_json' shared extension, used via _Py_EnterRecursiveCall()
 // static inline function.

Include/pythonrun.h

@@ -17,16 +17,32 @@ PyAPI_FUNC(void) PyErr_Display(PyObject *, PyObject *, PyObject *);
 PyAPI_FUNC(void) PyErr_DisplayException(PyObject *);
 #endif
 
+/* C frame size approximations in "pointers".
+ * Note: These are for "typical" C frames, we expect PyEval_EvalDefault
+ * to use three times as much stack space.
+ * TO DO: We should determine the numbers more accurately at build time.
+ */
+#ifdef Py_DEBUG
+/* Debug frames are larger, very much so for Clang -O0. */
+#  ifdef __clang__
+#    define Py_C_FRAME_SIZE 500
+#  else
+#    define Py_C_FRAME_SIZE 200
+#  endif
+#else
+#    define Py_C_FRAME_SIZE 50
+#endif
+
 
 /* Stuff with no proper home (yet) */
 PyAPI_DATA(int) (*PyOS_InputHook)(void);
 
 /* Stack size, in "pointers" (so we get extra safety margins
    on 64-bit platforms).  On a 32-bit platform, this translates
-   to an 8k margin. */
-#define PYOS_STACK_MARGIN 2048
+   to an 40k margin. */
+#define PYOS_STACK_MARGIN 10000
 
-#if defined(WIN32) && !defined(MS_WIN64) && !defined(_M_ARM) && defined(_MSC_VER) && _MSC_VER >= 1300
+#if defined(WIN32) && !defined(_M_ARM) && defined(_MSC_VER) && _MSC_VER >= 1300
 /* Enable stack checking under Microsoft C */
 // When changing the platforms, ensure PyOS_CheckStack() docs are still correct
 #define USE_STACKCHECK

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()

Lib/test/test_dictviews.py

@@ -279,7 +279,7 @@ def test_recursive_repr(self):
 
     def test_deeply_nested_repr(self):
         d = {}
-        for i in range(Py_C_RECURSION_LIMIT//2 + 100):
+        for i in range(50_000):
             d = {42: d.values()}
         self.assertRaises(RecursionError, repr, d)
 

Lib/test/test_exception_group.py

@@ -460,7 +460,7 @@ def test_basics_split_by_predicate__match(self):
 class DeepRecursionInSplitAndSubgroup(unittest.TestCase):
     def make_deep_eg(self):
         e = TypeError(1)
-        for i in range(Py_C_RECURSION_LIMIT + 1):
+        for i in range(50_000):
             e = ExceptionGroup('eg', [e])
         return e
 

Misc/NEWS.d/next/Core and Builtins/2023-12-31-23-14-13.gh-issue-113655.1IIsob.rst

@@ -0,0 +1,2 @@
+Use the PyOS_CheckStack to dynamically check for C stack usage on platforms
+that support it (just Windows for now).

Python/ceval.c

@@ -279,13 +279,6 @@ Py_SetRecursionLimit(int new_limit)
 int
 _Py_CheckRecursiveCall(PyThreadState *tstate, const char *where)
 {
-#ifdef USE_STACKCHECK
-    if (PyOS_CheckStack()) {
-        ++tstate->c_recursion_remaining;
-        _PyErr_SetString(tstate, PyExc_MemoryError, "Stack overflow");
-        return -1;
-    }
-#endif
     if (tstate->recursion_headroom) {
         if (tstate->c_recursion_remaining < -50) {
             /* Overflowing while handling an overflow. Give up. */
@@ -294,6 +287,12 @@ _Py_CheckRecursiveCall(PyThreadState *tstate, const char *where)
     }
     else {
         if (tstate->c_recursion_remaining <= 0) {
+#ifdef USE_STACKCHECK
+            if (PyOS_CheckStack() == 0) {
+                tstate->c_recursion_remaining += (int)(PYOS_STACK_MARGIN/Py_C_FRAME_SIZE);
+                return 0;
+            }
+#endif
             tstate->recursion_headroom++;
             _PyErr_Format(tstate, PyExc_RecursionError,
                         "maximum recursion depth exceeded%s",

Python/pythonrun.c

@@ -1525,7 +1525,7 @@ _Py_SourceAsString(PyObject *cmd, const char *funcname, const char *what, PyComp
 #include <excpt.h>
 
 /*
- * Return non-zero when we run out of memory on the stack; zero otherwise.
+ * Return non-zero when we are low on memory on the stack; zero otherwise.
  */
 int
 PyOS_CheckStack(void)