gh-138886: Remove deprecated PySys_ResetWarnOptions C-API function

Doc/c-api/init.rst

@@ -41,7 +41,7 @@ The following functions can be safely called before Python is initialized:
   * :c:func:`PyObject_SetArenaAllocator`
   * :c:func:`Py_SetProgramName`
   * :c:func:`Py_SetPythonHome`
-  * :c:func:`PySys_ResetWarnOptions`
+  * :c:func:`!PySys_ResetWarnOptions`
   * the configuration functions covered in :ref:`init-config`
 
 * Informative functions:

Doc/c-api/sys.rst

@@ -316,14 +316,6 @@ accessible to C code.  They all work with the current interpreter thread's
    case *name* is deleted from the sys module. Returns ``0`` on success, ``-1``
    on error.
 
-.. c:function:: void PySys_ResetWarnOptions()
-
-   Reset :data:`sys.warnoptions` to an empty list. This function may be
-   called prior to :c:func:`Py_Initialize`.
-
-   .. deprecated-removed:: 3.13 3.15
-      Clear :data:`sys.warnoptions` and :data:`!warnings.filters` instead.
-
 .. c:function:: void PySys_WriteStdout(const char *format, ...)
 
    Write the output string described by *format* to :data:`sys.stdout`.  No

Doc/deprecations/c-api-pending-removal-in-3.15.rst

@@ -59,7 +59,7 @@ Pending removal in Python 3.15
     Set :c:member:`PyConfig.program_name` instead.
   * :c:func:`!Py_SetPythonHome()`:
     Set :c:member:`PyConfig.home` instead.
-  * :c:func:`PySys_ResetWarnOptions`:
+  * :c:func:`!PySys_ResetWarnOptions`:
     Clear :data:`sys.warnoptions` and :data:`!warnings.filters` instead.
 
   The :c:func:`Py_InitializeFromConfig` API should be used with

Doc/whatsnew/3.13.rst

@@ -2490,7 +2490,7 @@ Deprecated C APIs
 
 * Deprecate old Python initialization functions:
 
-  * :c:func:`PySys_ResetWarnOptions`:
+  * :c:func:`!PySys_ResetWarnOptions`:
     Clear :data:`sys.warnoptions` and :data:`!warnings.filters` instead.
   * :c:func:`!Py_GetExecPrefix`:
     Get :data:`sys.exec_prefix` instead.

Doc/whatsnew/3.15.rst

@@ -800,6 +800,11 @@ Removed C APIs
   of :c:func:`PyImport_ImportModule`.
   (Contributed by Bénédikt Tran in :gh:`133644`.)
 
+* Remove deprecated :c:func:`!PySys_ResetWarnOptions`.
+  Clear :data:`sys.warnoptions` and :data:`!warnings.filters` instead.
+
+  (Contributed by Nikita Sobolev in :gh:`138886`.)
+
 The following functions are removed in favor of :c:func:`PyConfig_Get`.
 The |pythoncapi_compat_project| can be used to get :c:func:`!PyConfig_Get`
 on Python 3.13 and older.

Include/sysmodule.h

@@ -23,8 +23,6 @@ PyAPI_FUNC(void) PySys_WriteStderr(const char *format, ...)
 PyAPI_FUNC(void) PySys_FormatStdout(const char *format, ...);
 PyAPI_FUNC(void) PySys_FormatStderr(const char *format, ...);
 
-Py_DEPRECATED(3.13) PyAPI_FUNC(void) PySys_ResetWarnOptions(void);
-
 PyAPI_FUNC(PyObject *) PySys_GetXOptions(void);
 
 #ifdef __cplusplus

Lib/test/test_embed.py

@@ -315,9 +315,9 @@ def test_pre_initialization_sys_options(self):
             print(out)
             print(err)
         expected_output = (
-            "sys.warnoptions: ['once', 'module', 'default']\n"
+            "sys.warnoptions: ['default', 'once', 'module']\n"
             "sys._xoptions: {'not_an_option': '1', 'also_not_an_option': '2'}\n"
-            "warnings.filters[:3]: ['default', 'module', 'once']\n"
+            "warnings.filters[:3]: ['module', 'once', 'default']\n"
         )
         self.assertIn(expected_output, out)
         self.assertEqual(err, '')

Misc/NEWS.d/3.13.0a1.rst

@@ -6592,7 +6592,7 @@ functions, deprecated in Python 3.9. Patch by Victor Stinner.
 
 Deprecate old Python initialization functions:
 
-* :c:func:`PySys_ResetWarnOptions`
+* :c:func:`!PySys_ResetWarnOptions`
 * :c:func:`!Py_GetExecPrefix`
 * :c:func:`!Py_GetPath`
 * :c:func:`!Py_GetPrefix`

Misc/NEWS.d/next/C_API/2025-09-14-13-09-47.gh-issue-138886.dlcTXL.rst

@@ -0,0 +1 @@
+Remove deprecated :c:func:`!PySys_ResetWarnOptions` C-API function.

Misc/stable_abi.toml

@@ -1335,6 +1335,7 @@
     abi_only = true
 [function.PySys_ResetWarnOptions]
     added = '3.2'
+    abi_only = true
 [function.PySys_SetArgv]
     added = '3.2'
 [function.PySys_SetArgvEx]

Programs/_testembed.c

@@ -343,12 +343,9 @@ static int test_pre_initialization_sys_options(void)
 
     _Py_EMBED_PREINIT_CHECK("Checking PySys_AddWarnOption\n");
     PySys_AddWarnOption(L"default");
-    _Py_EMBED_PREINIT_CHECK("Checking PySys_ResetWarnOptions\n");
-    PySys_ResetWarnOptions();
     _Py_EMBED_PREINIT_CHECK("Checking PySys_AddWarnOption linked list\n");
     PySys_AddWarnOption(dynamic_once_warnoption);
     PySys_AddWarnOption(L"module");
-    PySys_AddWarnOption(L"default");
     _Py_EMBED_PREINIT_CHECK("Checking PySys_AddXOption\n");
     PySys_AddXOption(L"not_an_option=1");
     PySys_AddXOption(dynamic_xoption);

Python/sysmodule.c

@@ -3045,7 +3045,7 @@ get_warnoptions(PyThreadState *tstate)
     return warnoptions;
 }
 
-void
+PyAPI_FUNC(void)
 PySys_ResetWarnOptions(void)
 {
     PyThreadState *tstate = _PyThreadState_GET();