diff --git a/compiler/optimizing/instruction_builder.cc b/compiler/optimizing/instruction_builder.cc
index ca3b191..6532ec1 100644
--- a/compiler/optimizing/instruction_builder.cc
+++ b/compiler/optimizing/instruction_builder.cc
@@ -25,6 +25,7 @@
 #include "quicken_info.h"
 #include "scoped_thread_state_change-inl.h"
 #include "sharpening.h"
+#include "well_known_classes.h"
 
 namespace art {