diff --git a/src/ca/comQueSend.cpp b/src/ca/comQueSend.cpp
index 0bf89e68e..4a29b4db5 100644
--- a/src/ca/comQueSend.cpp
+++ b/src/ca/comQueSend.cpp
@@ -371,7 +371,7 @@ void comQueSend::insertRequestWithPayLoad (
         // the above checks verify that the total size
         // is lest that 0xffffffff
         size = static_cast < ca_uint32_t > 
-            ( dbr_size_n ( dataType, nElem ) );
+            ( dbr_size_n ( dataType, nElem ) ); // X aCC 392
         payloadSize = CA_MESSAGE_ALIGN ( size );
         this->insertRequestHeader ( request, payloadSize, 
             static_cast <ca_uint16_t> ( dataType ), 
diff --git a/src/ca/netSubscription.cpp b/src/ca/netSubscription.cpp
index 04003cae3..5c315834c 100644
--- a/src/ca/netSubscription.cpp
+++ b/src/ca/netSubscription.cpp
@@ -79,7 +79,7 @@ void netSubscription::show (
 }
 
 void netSubscription::completion ( 
-    epicsGuard < epicsMutex > & guard, cacRecycle & )
+    epicsGuard < epicsMutex > &, cacRecycle & )
 {
     errlogPrintf ( "subscription update w/o data ?\n" );
 }
diff --git a/src/ca/noopiiu.cpp b/src/ca/noopiiu.cpp
index 86aeaca0e..9c98447d9 100644
--- a/src/ca/noopiiu.cpp
+++ b/src/ca/noopiiu.cpp
@@ -142,7 +142,7 @@ double noopiiu::receiveWatchdogDelay (
 }
 
 void noopiiu::uninstallChan ( 
-    epicsGuard < epicsMutex > & guard, nciu & chan )
+    epicsGuard < epicsMutex > &, nciu & )
 {
     // intentionally does not call default in netiiu
 }
diff --git a/src/ca/syncGroupReadNotify.cpp b/src/ca/syncGroupReadNotify.cpp
index 075de038f..f84b52b85 100644
--- a/src/ca/syncGroupReadNotify.cpp
+++ b/src/ca/syncGroupReadNotify.cpp
@@ -115,7 +115,7 @@ void syncGroupReadNotify::exception (
 }
 
 void syncGroupReadNotify::show ( 
-    epicsGuard < epicsMutex > & guard, unsigned level ) const
+    epicsGuard < epicsMutex > &, unsigned level ) const
 {
     ::printf ( "pending sg read op: pVal=%p\n", this->pValue );
     if ( level > 0u ) {
diff --git a/src/ca/syncGroupWriteNotify.cpp b/src/ca/syncGroupWriteNotify.cpp
index 4b94294aa..267694662 100644
--- a/src/ca/syncGroupWriteNotify.cpp
+++ b/src/ca/syncGroupWriteNotify.cpp
@@ -105,7 +105,7 @@ void syncGroupWriteNotify::exception (
 }
 
 void syncGroupWriteNotify::show ( 
-    epicsGuard < epicsMutex > & guard, unsigned level ) const
+    epicsGuard < epicsMutex > &, unsigned level ) const
 {
     ::printf ( "pending write sg op\n" );
     if ( level > 0u ) {