diff --git a/extensions/openpower-pels/src.cpp b/extensions/openpower-pels/src.cpp
index cac9bf1..43bf205 100644
--- a/extensions/openpower-pels/src.cpp
+++ b/extensions/openpower-pels/src.cpp
@@ -1212,8 +1212,9 @@
             }
             else
             {
-                std::string msg =
-                    "Invalid priority found in dev callout JSON: " +
+                auto msg =
+                    std::string{
+                        "Invalid priority found in dev callout JSON: "} +
                     callout.priority[0];
                 addDebugData(msg);
             }