diff --git a/pdbApp/pvalink_link.cpp b/pdbApp/pvalink_link.cpp
index cf15966..62e6f5b 100644
--- a/pdbApp/pvalink_link.cpp
+++ b/pdbApp/pvalink_link.cpp
@@ -89,7 +89,9 @@ pvd::PVField::const_shared_pointer pvaLink::getSubField(const char *name)
         } else {
             // we access a sub-struct
             ret = lchan->op_mon.root->getSubField(fieldName);
-            if(ret->getField()->getType()!=pvd::structure) {
+            if(!ret) {
+                // noop
+            } else if(ret->getField()->getType()!=pvd::structure) {
                 // addressed sub-field isn't a sub-structure
                 if(strcmp(name, "value")!=0) {
                     // unless we are trying to fetch the "value", we fail here