diff --git a/android/apex.go b/android/apex.go
index a93baf6..bf11ba2 100644
--- a/android/apex.go
+++ b/android/apex.go
@@ -139,6 +139,7 @@
 
 var apexData OncePer
 var apexNamesMapMutex sync.Mutex
+var apexNamesKey = NewOnceKey("apexNames")
 
 // This structure maintains the global mapping in between modules and APEXes.
 // Examples:
@@ -147,7 +148,7 @@
 // apexNamesMap()["foo"]["bar"] == false: module foo is indirectly depended on by APEX bar
 // apexNamesMap()["foo"]["bar"] doesn't exist: foo is not built for APEX bar
 func apexNamesMap() map[string]map[string]bool {
-	return apexData.Once("apexNames", func() interface{} {
+	return apexData.Once(apexNamesKey, func() interface{} {
 		return make(map[string]map[string]bool)
 	}).(map[string]map[string]bool)
 }