diff -r bd0a95bec96b -r 9042ffe5b7fe src/hotspot/share/jvmci/jvmciRuntime.hpp
--- a/src/hotspot/share/jvmci/jvmciRuntime.hpp	Fri May 04 09:29:14 2018 +0200
+++ b/src/hotspot/share/jvmci/jvmciRuntime.hpp	Fri May 04 11:41:35 2018 +0200
@@ -150,8 +150,10 @@
   // printed as a string, otherwise the type of the object is printed
   // followed by its address.
   static void log_object(JavaThread* thread, oopDesc* object, bool as_string, bool newline);
+#if INCLUDE_G1GC
   static void write_barrier_pre(JavaThread* thread, oopDesc* obj);
   static void write_barrier_post(JavaThread* thread, void* card);
+#endif
   static jboolean validate_object(JavaThread* thread, oopDesc* parent, oopDesc* child);
 
   // used to throw exceptions from compiled JVMCI code