diff --git a/src/hb-face.cc b/src/hb-face.cc
index 89901d202..83c932f32 100644
--- a/src/hb-face.cc
+++ b/src/hb-face.cc
@@ -636,7 +636,7 @@ hb_face_collect_variation_unicodes (hb_face_t *face,
 struct face_table_info_t
 {
   hb_blob_t* data;
-  unsigned order;
+  signed order;
 };
 
 struct hb_face_builder_data_t
@@ -793,7 +793,7 @@ hb_face_builder_add_table (hb_face_t *face, hb_tag_t tag, hb_blob_t *blob)
   hb_face_builder_data_t *data = (hb_face_builder_data_t *) face->user_data;
 
   hb_blob_t* previous = data->tables.get (tag).data;
-  if (!data->tables.set (tag, face_table_info_t {hb_blob_reference (blob), 0}))
+  if (!data->tables.set (tag, face_table_info_t {hb_blob_reference (blob), -1}))
   {
     hb_blob_destroy (blob);
     return false;
@@ -828,7 +828,7 @@ hb_face_builder_sort_tables (hb_face_t *face,
   for (auto& info : data->tables.values_ref())
     info.order = -1;
 
-  unsigned order = 0;
+  signed order = 0;
   for (const hb_tag_t* tag = tags;
        *tag;
        tag++)