diff --git a/lib/cpp/test/Makefile.am b/lib/cpp/test/Makefile.am
index 012d226..751b0b3 100755
--- a/lib/cpp/test/Makefile.am
+++ b/lib/cpp/test/Makefile.am
@@ -268,7 +268,7 @@
 
 AM_CPPFLAGS = $(BOOST_CPPFLAGS) -I$(top_srcdir)/lib/cpp/src
 AM_LDFLAGS = $(BOOST_LDFLAGS)
-AM_CXXFLAGS = -Wall
+AM_CXXFLAGS = -Wall -Wextra
 
 clean-local:
 	$(RM) -r gen-cpp