bpo-45434: Only exclude <stdlib.h> in Python 3.11 limited C API (GH-29027)

The Python 3.11 limited C API no longer includes stdlib.h, stdio.h,
string.h and errno.h.

* Exclude Py_MEMCPY() from Python 3.11 limited C API.
* xxlimited C extension is now built with Python 3.11 limited C API.

1 files changed, 6 insertions, 4 deletions

diff --git a/Include/Python.h b/Include/Python.h
index c0a621ad44a..6e3303ac9a3 100644
--- a/Include/Python.h
+++ b/Include/Python.h
@@ -16,12 +16,14 @@
 #  define _SGI_MP_SOURCE
 #endif
 
-#include <string.h>               // memcpy()
-#ifndef Py_LIMITED_API
+// stdlib.h, stdio.h, errno.h and string.h headers are not used by Python
+// headers, but kept for backward compatibility. They are excluded from the
+// limited C API of Python 3.11.
+#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
+#  include <stdlib.h>
 #  include <stdio.h>              // FILE*
-#endif
-#ifdef HAVE_ERRNO_H
 #  include <errno.h>              // errno
+#  include <string.h>             // memcpy()
 #endif
 #ifndef MS_WINDOWS
 #  include <unistd.h>