Tidy up a bit

Author: markshannon

Doc/c-api/exceptions.rst

@@ -921,11 +921,7 @@ because the :ref:`call protocol <call>` takes care of recursion handling.
 
    Marks a point where a recursive C-level call is about to be performed.
 
-   If :c:macro:`!USE_STACKCHECK` is defined, this function checks if the OS
-   stack overflowed using :c:func:`PyOS_CheckStack`.  If this is the case, it
-   sets a :exc:`MemoryError` and returns a nonzero value.
-
-   The function then checks if the recursion limit is reached.  If this is the
+   The function then checks if the stack limit is reached.  If this is the
    case, a :exc:`RecursionError` is set and a nonzero value is returned.
    Otherwise, zero is returned.
 

Include/pythonrun.h

@@ -33,8 +33,6 @@ PyAPI_DATA(int) (*PyOS_InputHook)(void);
 #define PYOS_STACK_MARGIN_BYTES (PYOS_STACK_MARGIN * sizeof(void *))
 
 #if defined(WIN32)
-/* Enable stack checking under Microsoft C */
-// When changing the platforms, ensure PyOS_CheckStack() docs are still correct
 #define USE_STACKCHECK
 #endif
 

Python/ceval.c

@@ -337,13 +337,11 @@ _Py_EnterRecursiveCallUnchecked(PyThreadState *tstate)
 #elif defined(__ANDROID__)
 #  define Py_C_STACK_SIZE 1200000
 #elif defined(__sparc__)
-   // test_descr crashed on sparc64 with >7000 but let's keep a margin of error.
 #  define Py_C_STACK_SIZE 1600000
 #elif defined(__wasi__)
    /* Web assembly has two stacks, so this isn't really the stack depth */
 #  define Py_C_STACK_SIZE 100000
 #elif defined(__hppa__) || defined(__powerpc64__)
-   // test_descr crashed with >8000 but let's keep a margin of error.
 #  define Py_C_STACK_SIZE 2000000
 #else
 #  define Py_C_STACK_SIZE 5000000

Python/pythonrun.c

@@ -1528,37 +1528,21 @@ _Py_SourceAsString(PyObject *cmd, const char *funcname, const char *what, PyComp
 }
 
 #if defined(USE_STACKCHECK)
-#if defined(WIN32) && defined(_MSC_VER)
 
-/* Stack checking for Microsoft C */
-
-#include <malloc.h>
-#include <excpt.h>
+/* Stack checking */
 
 /*
  * Return non-zero when we run out of memory on the stack; zero otherwise.
  */
 int PyOS_CheckStack(void)
 {
-    char here;
-    uintptr_t here_addr = (uintptr_t)&here;
     PyThreadState *tstate = _PyThreadState_GET();
-    _PyThreadStateImpl *_tstate = (_PyThreadStateImpl *)tstate;
-    if (_tstate->c_stack_hard_limit == 0) {
-        _Py_InitializeRecursionLimits(tstate);
-    }
-    if (here_addr >= _tstate->c_stack_soft_limit) {
-        return 0;
-    }
-    else {
+    if (_Py_ReachedRecursionLimit(tstate)) {
         return -1;
     }
+    return 0;
 }
 
-#endif /* WIN32 && _MSC_VER */
-
-/* Alternate implementations can be added here... */
-
 #endif /* USE_STACKCHECK */
 
 /* Deprecated C API functions still provided for binary compatibility */