diff --git a/test/DebugProtoTest_extras.cpp b/test/DebugProtoTest_extras.cpp
new file mode 100644
index 0000000..b1178a3
--- /dev/null
+++ b/test/DebugProtoTest_extras.cpp
@@ -0,0 +1,13 @@
+// Extra functions required for DebugProtoTest_types to work
+
+#include "gen-cpp/DebugProtoTest_types.h"
+
+
+namespace thrift { namespace test { namespace debug {
+
+bool Empty::operator<(Empty const& other) const {
+  // It is empty, so all are equal.
+  return false;
+}
+
+}}}
diff --git a/test/Makefile.am b/test/Makefile.am
index 5f2ce8d..cc92ce0 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -19,7 +19,8 @@
 	gen-cpp/ThriftTest_constants.cpp \
 	gen-cpp/ThriftTest.cpp \
 	gen-cpp/ThriftTest_types.cpp \
-	ThriftTest_extras.cpp
+	ThriftTest_extras.cpp \
+	DebugProtoTest_extras.cpp
 
 libtestgencpp_la_LIBADD = $(top_builddir)/lib/cpp/libthrift.la