diff --git a/dexpreopt/config.go b/dexpreopt/config.go
index c24caac..13a14f4 100644
--- a/dexpreopt/config.go
+++ b/dexpreopt/config.go
@@ -32,7 +32,10 @@
 
 	DisableGenerateProfile bool // don't generate profiles
 
-	BootJars         []string // jars that form the boot image
+	PreoptBootClassPathDexFiles     []string // file paths of boot class path files
+	PreoptBootClassPathDexLocations []string // virtual locations of boot class path files
+
+	BootJars         []string // modules for jars that form the boot class path
 	SystemServerJars []string // jars that form the system server
 	SystemServerApps []string // apps that are loaded into system server
 	SpeedApps        []string // apps that should be speed optimized