diff --git a/src/libCom/test/cvtFastPerform.cpp b/src/libCom/test/cvtFastPerform.cpp
index 404fd63ae..a8338c688 100644
--- a/src/libCom/test/cvtFastPerform.cpp
+++ b/src/libCom/test/cvtFastPerform.cpp
@@ -11,6 +11,7 @@
 #include "epicsTime.h"
 #include "testMain.h"
 
+using namespace std;
 
 typedef void ( * PTestFunc ) ( const double &, char * pBug, size_t bufSize );