diff --git a/test/boost_no_std_wstreambuf.ipp b/test/boost_no_std_wstreambuf.ipp
index ee19b570..308094bf 100644
--- a/test/boost_no_std_wstreambuf.ipp
+++ b/test/boost_no_std_wstreambuf.ipp
@@ -8,6 +8,8 @@
 //  DESCRIPTION:   The standard library lacks std::basic_streambuf<wchar_t>.
 
 #include <iostream>
+#include <streambuf>
+#include <string>
 
 namespace boost_no_std_wstreambuf{