diff --git a/lib/libesp32/Berry-0.1.10/src/be_debuglib.c b/lib/libesp32/Berry-0.1.10/src/be_debuglib.c
index 97123916b..9989da064 100644
--- a/lib/libesp32/Berry-0.1.10/src/be_debuglib.c
+++ b/lib/libesp32/Berry-0.1.10/src/be_debuglib.c
@@ -40,7 +40,9 @@ static void dump_module(bmodule *module)
 
 static void dump_class(bclass *class)
 {
-    dump_map(class->members);
+    if (class->members) {
+        dump_map(class->members);
+    }
 }
 
 static void dump_instanse(binstance *ins)