diff --git a/lib/cpp/test/processor/EventLog.cpp b/lib/cpp/test/processor/EventLog.cpp
index c8e0d9b..c75955d 100644
--- a/lib/cpp/test/processor/EventLog.cpp
+++ b/lib/cpp/test/processor/EventLog.cpp
@@ -98,7 +98,7 @@
     while (events_.empty()) {
       monitor_.wait(timeout);
     }
-  } catch (TimedOutException ex) {
+  } catch (const TimedOutException &) {
     return Event(ET_LOG_END, 0, 0, "");
   }
 
@@ -119,7 +119,7 @@
       while (it == events_.end()) {
         monitor_.wait(timeout);
       }
-    } catch (TimedOutException ex) {
+    } catch (const TimedOutException &) {
       return Event(ET_LOG_END, 0, 0, "");
     }