diff --git a/src/haiku_font_support.cc b/src/haiku_font_support.cc
index 3930cd965f6..549c54d8649 100644
--- a/src/haiku_font_support.cc
+++ b/src/haiku_font_support.cc
@@ -68,7 +68,11 @@ estimate_font_ascii (BFont *font, int *max_width,
 
   *min_width = min;
   *max_width = max;
-  *avg_width = total / count;
+
+  if (count)
+    *avg_width = total / count;
+  else
+    *avg_width = 0;
 }
 
 void