atexit is a builtin module now, provide that on Windows.
diff --git a/PC/config.c b/PC/config.c
index 68fa84f..38d91de 100644
--- a/PC/config.c
+++ b/PC/config.c
@@ -60,6 +60,7 @@
extern void init_ast(void);
extern void init_types(void);
extern void init_fileio(void);
+extern void initatexit(void);
/* tools/freeze/makeconfig.py marker for additional "extern" */
/* -- ADDMODULE MARKER 1 -- */
@@ -147,6 +148,7 @@
{"_types", init_types},
{"_fileio", init_fileio},
+ {"atexit", initatexit},
/* Sentinel */
{0, 0}