diff --git a/VariableAnalysis/Lib/Constants.php b/VariableAnalysis/Lib/Constants.php
index d69b1ba8..5dc51497 100644
--- a/VariableAnalysis/Lib/Constants.php
+++ b/VariableAnalysis/Lib/Constants.php
@@ -24,6 +24,9 @@ public static function getPassByReferenceFunctions() {
       'apc_dec' => [3],
       'apc_fetch' => [2],
       'apc_inc' => [3],
+      'apcu_dec' => [3],
+      'apcu_fetch' => [2],
+      'apcu_inc' => [3],
       'areConfusable' => [3],
       'array_multisort' => [1],
       'array_pop' => [1],