```
diff --git a/core/src/main/java/org/jruby/runtime/callsite/CachingCallSite.java b/core/src/main/java/org/jruby/runtime/callsite/CachingCallSite.java
index ea576b37c9..0d05b5c29f 100644
--- a/core/src/main/java/org/jruby/runtime/callsite/CachingCallSite.java
+++ b/core/src/main/java/org/jruby/runtime/callsite/CachingCallSite.java
@@ -313,7 +313,10 @@ public abstract class CachingCallSite extends CallSite {
 
     private CacheEntry cacheAndGet(IRubyObject self, RubyClass selfType, String methodName) {
         CacheEntry entry = selfType.searchWithCache(methodName);
-        if (!entry.method.isUndefined()) entry = setCache(entry, self);
+        if (!entry.method.isUndefined()) {
+            entry = setCache(entry, self);
+            if (entry.method.isBuiltin()) builtinCache = entry;
+        }
         return entry;
     }
```