diff --git a/src/hb-open-file-private.hh b/src/hb-open-file-private.hh
index f7e80a3..de76a96 100644
--- a/src/hb-open-file-private.hh
+++ b/src/hb-open-file-private.hh
@@ -110,9 +110,9 @@
   protected:
   Tag		sfnt_version;	/* '\0\001\0\00' if TrueType / 'OTTO' if CFF */
   USHORT	numTables;	/* Number of tables. */
-  USHORT	searchRange;	/* (Maximum power of 2 <= numTables) x 16 */
-  USHORT	entrySelector;	/* Log2(maximum power of 2 <= numTables). */
-  USHORT	rangeShift;	/* NumTables x 16-searchRange. */
+  USHORT	searchRangeZ;	/* (Maximum power of 2 <= numTables) x 16 */
+  USHORT	entrySelectorZ;	/* Log2(maximum power of 2 <= numTables). */
+  USHORT	rangeShiftZ;	/* NumTables x 16-searchRange. */
   TableRecord	tables[VAR];	/* TableRecord entries. numTables items */
   public:
   DEFINE_SIZE_ARRAY (12, tables);