diff --git a/src/mrw/checkcxx11.hxx b/src/mrw/checkcxx11.hxx
index f4899c8..b61a785 100644
--- a/src/mrw/checkcxx11.hxx
+++ b/src/mrw/checkcxx11.hxx
@@ -8,6 +8,8 @@
 #ifndef __MRW__CHECKCXX11__
 #define __MRW__CHECKCXX11__
 
+#      include <memory>
+
 // check if code is compiled with a new C++11 compiler
 // otherwise there is a fallback wich makes everything much more compliacted
 #  ifndef MRW__OLD_PRE11_COMPILER