diff --git a/mozilla/docshell/base/nsWebShell.cpp b/mozilla/docshell/base/nsWebShell.cpp
index 9a32b9c30ea..c7652c580e7 100644
--- a/mozilla/docshell/base/nsWebShell.cpp
+++ b/mozilla/docshell/base/nsWebShell.cpp
@@ -2566,7 +2566,7 @@ nsWebShell::GetURL(PRInt32 aHistoryIndex, const PRUnichar** aURLResult)
 void
 nsWebShell::ShowHistory()
 {
-#ifdef OLD_HISTORY
+#if defined(OLD_HISTORY) && defined(NS_DEBUG)
   if (WEB_LOG_TEST(gLogModule, WEB_TRACE_HISTORY)) {
     PRInt32 i, n = mHistory.Count();
     for (i = 0; i < n; i++) {
diff --git a/mozilla/webshell/src/nsWebShell.cpp b/mozilla/webshell/src/nsWebShell.cpp
index 9a32b9c30ea..c7652c580e7 100644
--- a/mozilla/webshell/src/nsWebShell.cpp
+++ b/mozilla/webshell/src/nsWebShell.cpp
@@ -2566,7 +2566,7 @@ nsWebShell::GetURL(PRInt32 aHistoryIndex, const PRUnichar** aURLResult)
 void
 nsWebShell::ShowHistory()
 {
-#ifdef OLD_HISTORY
+#if defined(OLD_HISTORY) && defined(NS_DEBUG)
   if (WEB_LOG_TEST(gLogModule, WEB_TRACE_HISTORY)) {
     PRInt32 i, n = mHistory.Count();
     for (i = 0; i < n; i++) {