diff --git a/Source/JavaScriptCore/offlineasm/self_hash.rb b/Source/JavaScriptCore/offlineasm/self_hash.rb
index 2c300fc..b910573 100644
--- a/Source/JavaScriptCore/offlineasm/self_hash.rb
+++ b/Source/JavaScriptCore/offlineasm/self_hash.rb
@@ -21,6 +21,7 @@
 # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 # THE POSSIBILITY OF SUCH DAMAGE.
 
+require "config"
 require "digest/sha1"
 require "pathname"