diff --git a/Volume.h b/Volume.h
index f81afff..64cd7cb 100644
--- a/Volume.h
+++ b/Volume.h
@@ -51,6 +51,7 @@
     char *mMountpoint;
     VolumeManager *mVm;
     bool mDebug;
+    int mPartIdx;
 
     /*
      * The major/minor tuple of the currently mounted filesystem.