diff --git a/bt/includes/init_tr.php b/bt/includes/init_tr.php
index 87b49931..8311c40e 100644
--- a/bt/includes/init_tr.php
+++ b/bt/includes/init_tr.php
@@ -443,6 +443,7 @@ class sql_db
 	*/
 	function debug_find_source ($mode = '')
 	{
+		if (!SQL_PREPEND_SRC_COMM) return '';
 		foreach (debug_backtrace() as $trace)
 		{
 			if ($trace['file'] !== __FILE__)
diff --git a/library/includes/cache/common.php b/library/includes/cache/common.php
index 0320b667..d18c4633 100644
--- a/library/includes/cache/common.php
+++ b/library/includes/cache/common.php
@@ -74,6 +74,7 @@ class cache_common
 	*/
 	function debug_find_source ($mode = '')
 	{
+		if (!SQL_PREPEND_SRC_COMM) return '';
 		foreach (debug_backtrace() as $trace)
 		{
 			if ($trace['file'] !== __FILE__)
diff --git a/library/includes/core/mysql.php b/library/includes/core/mysql.php
index f3cb8cf9..2b67e2d4 100644
--- a/library/includes/core/mysql.php
+++ b/library/includes/core/mysql.php
@@ -829,6 +829,7 @@ class sql_db
 	*/
 	function debug_find_source ($mode = '')
 	{
+		if (!SQL_PREPEND_SRC_COMM) return '';
 		foreach (debug_backtrace() as $trace)
 		{
 			if ($trace['file'] !== __FILE__)
diff --git a/library/includes/datastore/common.php b/library/includes/datastore/common.php
index c0d2d212..249dcb94 100644
--- a/library/includes/datastore/common.php
+++ b/library/includes/datastore/common.php
@@ -165,6 +165,7 @@ class datastore_common
 	*/
 	function debug_find_source ($mode = '')
 	{
+		if (!SQL_PREPEND_SRC_COMM) return '';
 		foreach (debug_backtrace() as $trace)
 		{
 			if ($trace['file'] !== __FILE__)