bpo-45743: Move __APPLE_USE_RFC_3542 into socketmodule.c (GH-29456)

Author: tiran

Modules/socketmodule.c

@@ -86,6 +86,8 @@ Local naming conventions:
 */
 
 #ifdef __APPLE__
+// Issue #35569: Expose RFC 3542 socket options.
+#define __APPLE_USE_RFC_3542 1
 #include <AvailabilityMacros.h>
 /* for getaddrinfo thread safety test on old versions of OS X */
 #ifndef MAC_OS_X_VERSION_10_5

setup.py

@@ -1222,13 +1222,7 @@ def detect_crypt(self):
         self.add(Extension('_crypt', ['_cryptmodule.c'], libraries=libs))
 
     def detect_socket(self):
-        # socket(2)
-        kwargs = {'depends': ['socketmodule.h']}
-        if MACOS:
-            # Issue #35569: Expose RFC 3542 socket options.
-            kwargs['extra_compile_args'] = ['-D__APPLE_USE_RFC_3542']
-
-        self.add(Extension('_socket', ['socketmodule.c'], **kwargs))
+        self.add(Extension('_socket', ['socketmodule.c'], depends=['socketmodule.h']))
 
     def detect_dbm_gdbm(self):
         # Modules that provide persistent dictionary-like semantics.  You will