--- afdko/a4/runtime/src/atn/ProfilingATNSimulator.cpp
+++ afdko/a4/runtime/src/atn/ProfilingATNSimulator.cpp
@@ -11,6 +11,8 @@
 
 #include "atn/ProfilingATNSimulator.h"
 
+#include <chrono>
+
 using namespace antlr4;
 using namespace antlr4::atn;
 using namespace antlr4::dfa;