diff --git a/src/hb-font.cc b/src/hb-font.cc
index d27961db9..cce4359ce 100644
--- a/src/hb-font.cc
+++ b/src/hb-font.cc
@@ -1556,6 +1556,10 @@ hb_font_set_var_coords_normalized (hb_font_t *font,
   if (font->immutable)
     return;
 
+  /* Skip tail zero entries. */
+  while (coords_length && !coords[coords_length - 1])
+    coords_length--;
+
   int *copy = (int *) calloc (coords_length, sizeof (coords[0]));
   if (unlikely (!copy))
     return;