diff --git a/src/conf/storage_conf.c b/src/conf/storage_conf.c
index 4ccb791986d7eef5fe556575a53acb40a46f33c2..d21625735755f2d264d101408981436812891692 100644
--- a/src/conf/storage_conf.c
+++ b/src/conf/storage_conf.c
@@ -1484,7 +1484,7 @@ virStorageVolDefFormat(virStoragePoolDefPtr pool,
 
     virBufferAddLit(&buf, "<volume>\n");
     virBufferAsprintf(&buf,"  <name>%s</name>\n", def->name);
-    virBufferAsprintf(&buf,"  <key>%s</key>\n", def->key ? def->key : "(null)");
+    virBufferAsprintf(&buf,"  <key>%s</key>\n", NULLSTR(def->key));
     virBufferAddLit(&buf, "  <source>\n");
 
     if (def->source.nextent) {