diff --git a/src/one-body-sample.cc b/src/one-body-sample.cc
index 75a802f986a139211758bcd1f37b5ecd5a003def..6eaaaf133ca8073e7ade79e05ccb726d2c7c7d4f 100644
--- a/src/one-body-sample.cc
+++ b/src/one-body-sample.cc
@@ -4,6 +4,10 @@
 #include "config.h"
 #endif
 
+#ifdef HAVE_IPOPT
+#undef HAVE_IPOPT
+#endif
+
 #include <exception>
 #include <iostream>