diff --git a/src/ca/cacIO.h b/src/ca/cacIO.h
index ce8f39d22..45a8f76a1 100644
--- a/src/ca/cacIO.h
+++ b/src/ca/cacIO.h
@@ -45,6 +45,7 @@
 //
 //
 
+#include <new>
 #include <stdarg.h>
 
 #ifdef epicsExportSharedSymbols