diff --git a/ChangeLog b/ChangeLog
index 1841aa559a..9ce98258ea 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -92,6 +92,7 @@ phpMyAdmin - ChangeLog
 - issue #12625 Broken Edit links in query results of JOIN query
 - issue #12634 Drop DB error in import if DB doesn't exist
 - issue #12338 Designer reverts to first saved ER after EACH relation create or delete
+- issue #12639 'Show trace' in Console generates JS error for functions in query's trace called without any arguments
 
 4.6.4 (2016-08-16)
 - issue        [security] Weaknesses with cookie encryption, see PMASA-2016-29
diff --git a/js/console.js b/js/console.js
index 94f7c6cccd..6bdbb90f1e 100644
--- a/js/console.js
+++ b/js/console.js
@@ -1229,7 +1229,7 @@ PMA_consoleDebug = {
             functionName += dbgStep.type;
         }
         functionName += dbgStep.function;
-        if (dbgStep.args.length) {
+        if (dbgStep.args && dbgStep.args.length) {
             functionName += '(...)';
         } else {
             functionName += '()';
@@ -1297,7 +1297,7 @@ PMA_consoleDebug = {
                             .append(
                             $('<span class="file">').text(this._formatFileName(step))
                         );
-                    if (step.args.length) {
+                    if (step.args && step.args.length) {
                         $stepElem
                             .append(
                             $('<span class="args">').html(this._formatFunctionArgs(step))