diff --git a/simplecpp.cpp b/simplecpp.cpp
index 9c3f3a01..3cce780e 100755
--- a/simplecpp.cpp
+++ b/simplecpp.cpp
@@ -22,6 +22,7 @@
 #include <exception>
 #include <fstream>
 #include <iostream>
+#include <istream>
 #include <limits>
 #include <list>
 #include <map>
diff --git a/simplecpp.h b/simplecpp.h
index 398024d1..88a14014 100755
--- a/simplecpp.h
+++ b/simplecpp.h
@@ -8,7 +8,7 @@
 
 #include <cctype>
 #include <cstring>
-#include <istream>
+#include <iosfwd>
 #include <list>
 #include <map>
 #include <set>