From c6e418d1744aed95a6f25d22565204649dde29c7 Mon Sep 17 00:00:00 2001
From: Victor Stinner <vstinner@python.org>
Date: Wed, 11 Feb 2026 18:38:23 +0100
Subject: [PATCH] gh-141563: Enable test_cppext internal C API tests on macOS
 (#144711)

Build the C API in C++11 mode on macOS.
---
 Lib/test/test_cppext/__init__.py   | 14 +++++++++++---
 Lib/test/test_cppext/extension.cpp |  5 ++---
 Lib/test/test_cppext/setup.py      |  2 +-
 3 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/Lib/test/test_cppext/__init__.py b/Lib/test/test_cppext/__init__.py
index 9013503995bd..1fd01702f640 100644
--- a/Lib/test/test_cppext/__init__.py
+++ b/Lib/test/test_cppext/__init__.py
@@ -4,6 +4,7 @@ import os.path
 import shlex
 import shutil
 import subprocess
+import sys
 import unittest
 from test import support
 
@@ -27,9 +28,6 @@ SETUP = os.path.join(os.path.dirname(__file__), 'setup.py')
 class BaseTests:
     TEST_INTERNAL_C_API = False
 
-    def test_build(self):
-        self.check_build('_testcppext')
-
     def check_build(self, extension_name, std=None, limited=False):
         venv_dir = 'env'
         with support.setup_venv_with_pip_setuptools(venv_dir) as python_exe:
@@ -91,6 +89,9 @@ class BaseTests:
 
 
 class TestPublicCAPI(BaseTests, unittest.TestCase):
+    def test_build(self):
+        self.check_build('_testcppext')
+
     @support.requires_gil_enabled('incompatible with Free Threading')
     def test_build_limited_cpp03(self):
         self.check_build('_test_limited_cpp03ext', std='c++03', limited=True)
@@ -119,6 +120,13 @@ class TestPublicCAPI(BaseTests, unittest.TestCase):
 class TestInteralCAPI(BaseTests, unittest.TestCase):
     TEST_INTERNAL_C_API = True
 
+    def test_build(self):
+        kwargs = {}
+        if sys.platform == 'darwin':
+            # Old Apple clang++ default C++ std is gnu++98
+            kwargs['std'] = 'c++11'
+        self.check_build('_testcppext_internal', **kwargs)
+
 
 if __name__ == "__main__":
     unittest.main()
diff --git a/Lib/test/test_cppext/extension.cpp b/Lib/test/test_cppext/extension.cpp
index 06ef997d57af..92c4645039a0 100644
--- a/Lib/test/test_cppext/extension.cpp
+++ b/Lib/test/test_cppext/extension.cpp
@@ -16,9 +16,8 @@
 #ifdef TEST_INTERNAL_C_API
    // gh-135906: Check for compiler warnings in the internal C API
 #  include "internal/pycore_frame.h"
-   // mimalloc emits compiler warnings when Python is built on Windows
-   // and macOS.
-#  if !defined(MS_WINDOWS) && !defined(__APPLE__)
+   // mimalloc emits compiler warnings on Windows.
+#  if !defined(MS_WINDOWS)
 #    include "internal/pycore_backoff.h"
 #    include "internal/pycore_cell.h"
 #  endif
diff --git a/Lib/test/test_cppext/setup.py b/Lib/test/test_cppext/setup.py
index a3eec1c67e15..2d9052a6b879 100644
--- a/Lib/test/test_cppext/setup.py
+++ b/Lib/test/test_cppext/setup.py
@@ -59,7 +59,7 @@ def main():
         else:
             cppflags.append(f'-std={std}')
 
-        if limited or (std != 'c++03'):
+        if limited or (std != 'c++03') and not internal:
             # See CPPFLAGS_PEDANTIC docstring
             cppflags.extend(CPPFLAGS_PEDANTIC)
 
-- 
2.47.3