Make some private symbols static.
diff --git a/Python/compile.c b/Python/compile.c
index 1fb85e7..0939f05 100644
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -374,7 +374,8 @@
         PyFutureFeatures *c_future; /* pointer to module's __future__ */
 };
 
-int is_free(int v)
+static int
+is_free(int v)
 {
 	if ((v & (USE | DEF_FREE))
 	    && !(v & (DEF_LOCAL | DEF_PARAM | DEF_GLOBAL)))