diff --git a/src/cas/generic/casAsyncExIOI.cc b/src/cas/generic/casAsyncExIOI.cc
index 3ee210bff..cd53f30b1 100644
--- a/src/cas/generic/casAsyncExIOI.cc
+++ b/src/cas/generic/casAsyncExIOI.cc
@@ -29,6 +29,9 @@
  *
  * History
  * $Log$
+ * Revision 1.5  1997/08/05 00:46:58  jhill
+ * fixed warnings
+ *
  * Revision 1.4  1997/06/13 09:15:53  jhill
  * connect proto changes
  *
@@ -78,7 +81,7 @@ casAsyncExIOI::~casAsyncExIOI()
 //
 // casAsyncExIOI::postIOCompletion()
 //
-epicsShareFunc caStatus casAsyncExIOI::postIOCompletion(const pvExistReturn retValIn)
+epicsShareFunc caStatus casAsyncExIOI::postIOCompletion(const pvExistReturn &retValIn)
 {
 	this->retVal = retValIn; 
 	return this->postIOCompletionI();
diff --git a/src/cas/generic/casdef.h b/src/cas/generic/casdef.h
index 880b262bd..3cc996a3d 100644
--- a/src/cas/generic/casdef.h
+++ b/src/cas/generic/casdef.h
@@ -868,7 +868,7 @@ public:
 	// (this function does not delete the casAsyncIO object). 
 	// Only the first call to this function has any effect.
 	//
-	epicsShareFunc caStatus postIOCompletion(const pvExistReturn retValIn)
+	epicsShareFunc caStatus postIOCompletion(const pvExistReturn &retValIn)
 	{
 		return this->casAsyncExIOI::postIOCompletion (retValIn);
 	}