Minor optimization
diff --git a/Lib/fontTools/ttLib/tables/_c_m_a_p.py b/Lib/fontTools/ttLib/tables/_c_m_a_p.py
index a9f388b..a356c3c 100644
--- a/Lib/fontTools/ttLib/tables/_c_m_a_p.py
+++ b/Lib/fontTools/ttLib/tables/_c_m_a_p.py
@@ -673,7 +673,7 @@
glyphID = charCode + idDelta[i]
else:
# *someone* needs to get killed.
- index = idRangeOffset[i] // 2 + (charCode - startCode[i]) + i - len(idRangeOffset)
+ index = rangeOffset // 2 + (charCode - startCode[i]) + i - len(idRangeOffset)
assert (index < lenGIArray), "In format 4 cmap, range (%d), the calculated index (%d) into the glyph index array is not less than the length of the array (%d) !" % (i, index, lenGIArray)
if glyphIndexArray[index] != 0: # if not missing glyph
glyphID = glyphIndexArray[index] + idDelta[i]