diff --git a/src/hb-graphite2.cc b/src/hb-graphite2.cc
index 15d6ce80b..9d2252b84 100644
--- a/src/hb-graphite2.cc
+++ b/src/hb-graphite2.cc
@@ -223,7 +223,7 @@ struct hb_graphite2_cluster_t {
   unsigned int base_glyph;
   unsigned int num_glyphs;
   unsigned int cluster;
-  unsigned int advance;
+  int advance;
 };
 
 hb_bool_t