diff --git a/cpdftruetype.ml b/cpdftruetype.ml
index 31ed9a8..080883c 100644
--- a/cpdftruetype.ml
+++ b/cpdftruetype.ml
@@ -499,8 +499,11 @@ let parse ?(subset=[]) data encoding =
             | (_, _, o, l)::_ -> o, l
             | [] -> raise (Pdf.PDFError "No loca table found in TrueType font")
           in
+            let subset_1 = if subset = [] then [] else tl subset in
+            let subset_2 = if subset = [] then [] else [hd subset] in
             let flags = calculate_flags italicangle in
-            let firstchar, lastchar = calculate_limits subset in
+            let firstchar_1, lastchar_1 = calculate_limits subset_1 in
+            let firstchar_2, lastchar_2 = calculate_limits subset_2 in
             let numOfLongHorMetrics =
               match keep (function (t, _, _, _) -> string_of_tag t = "hhea") !tables with
               | (_, _, o, l)::_ -> let b = mk_b (i32toi o) in read_hhea_table b
@@ -511,7 +514,8 @@ let parse ?(subset=[]) data encoding =
               | (_, _, o, _)::_ -> read_hmtx_table numOfLongHorMetrics (mk_b (i32toi o))
               | [] -> raise (Pdf.PDFError "No hmtx table found in TrueType font")
             in
-            let widths = calculate_widths unitsPerEm encoding firstchar lastchar subset !glyphcodes hmtxdata in
+            let widths_1 = calculate_widths unitsPerEm encoding firstchar_1 lastchar_1 subset_1 !glyphcodes hmtxdata in
+            let widths_2 = calculate_widths unitsPerEm encoding firstchar_2 lastchar_2 subset_2 !glyphcodes hmtxdata in
             let maxwidth = calculate_maxwidth unitsPerEm hmtxdata in
             let stemv = calculate_stemv () in
             let b = mk_b (i32toi locaoffset) in
@@ -522,11 +526,11 @@ let parse ?(subset=[]) data encoding =
               | [] -> raise (Pdf.PDFError "No glyf table found in TrueType font")
             in
             let main_subset =
-              subset_font major minor !tables indexToLocFormat (if subset = [] then [] else tl subset)
+              subset_font major minor !tables indexToLocFormat subset_1
               encoding !glyphcodes loca mk_b glyfoffset data
             in
             let second_subset =
-              subset_font major minor !tables indexToLocFormat (if subset = [] then [] else [hd subset])
+              subset_font major minor !tables indexToLocFormat subset_2
               encoding !glyphcodes loca mk_b glyfoffset data
             in
               let second_tounicode =
@@ -536,9 +540,9 @@ let parse ?(subset=[]) data encoding =
                     Some h
               in
               [{flags; minx; miny; maxx; maxy; italicangle; ascent; descent;
-                capheight; stemv; xheight; avgwidth; maxwidth; firstchar; lastchar;
-                widths; subset_fontfile = main_subset; subset = if subset = [] then [] else tl subset; tounicode = None};
+                capheight; stemv; xheight; avgwidth; maxwidth; firstchar = firstchar_1; lastchar = lastchar_1;
+                widths = widths_1; subset_fontfile = main_subset; subset = subset_1; tounicode = None};
                {flags; minx; miny; maxx; maxy; italicangle; ascent; descent;
-                capheight; stemv; xheight; avgwidth; maxwidth; firstchar; lastchar;
-                widths; subset_fontfile = second_subset; subset = if subset = [] then [] else [hd subset];
+                capheight; stemv; xheight; avgwidth; maxwidth; firstchar = firstchar_2; lastchar = lastchar_2;
+                widths = widths_2; subset_fontfile = second_subset; subset = subset_2;
                 tounicode = second_tounicode}]