diff --git a/ext/rbs_extension/location.h b/ext/rbs_extension/location.h
index 63b926e55d..a898eaea38 100644
--- a/ext/rbs_extension/location.h
+++ b/ext/rbs_extension/location.h
@@ -20,7 +20,7 @@ typedef struct {
   unsigned short len;
   unsigned short cap;
   rbs_loc_entry_bitmap required_p;
-  rbs_loc_entry entries[0];
+  rbs_loc_entry entries[];
 } rbs_loc_children;
 
 typedef struct {