bpo-42688: Fix ffi alloc/free when using external libffi on macos (GH-23868)

Automerge-Triggered-By: GH:ronaldoussoren

Author: erykoff

Modules/_ctypes/malloc_closure.c

@@ -91,11 +91,15 @@ static void more_core(void)
 /* put the item back into the free list */
 void Py_ffi_closure_free(void *p)
 {
-#if USING_APPLE_OS_LIBFFI && HAVE_FFI_CLOSURE_ALLOC
+#if HAVE_FFI_CLOSURE_ALLOC
+#if USING_APPLE_OS_LIBFFI
     if (__builtin_available(macos 10.15, ios 13, watchos 6, tvos 13, *)) {
+#endif
         ffi_closure_free(p);
         return;
+#if USING_APPLE_OS_LIBFFI
     }
+#endif
 #endif
     ITEM *item = (ITEM *)p;
     item->next = free_list;
@@ -105,10 +109,14 @@ void Py_ffi_closure_free(void *p)
 /* return one item from the free list, allocating more if needed */
 void *Py_ffi_closure_alloc(size_t size, void** codeloc)
 {
-#if USING_APPLE_OS_LIBFFI && HAVE_FFI_CLOSURE_ALLOC
+#if HAVE_FFI_CLOSURE_ALLOC
+#if USING_APPLE_OS_LIBFFI
     if (__builtin_available(macos 10.15, ios 13, watchos 6, tvos 13, *)) {
+#endif
         return ffi_closure_alloc(size, codeloc);
+#if USING_APPLE_OS_LIBFFI
     }
+#endif
 #endif
     ITEM *item;
     if (!free_list)