diff --git a/src/gui_haiku.cc b/src/gui_haiku.cc
index a1c7e3e..644c2db 100644
--- a/src/gui_haiku.cc
+++ b/src/gui_haiku.cc
@@ -638,7 +638,7 @@
     {0,		    0, 0}
 };
 
-#define NUM_SPECIAL_KEYS    (sizeof(special_keys)/sizeof(special_keys[0]))
+#define NUM_SPECIAL_KEYS    ARRAY_LENGTH(special_keys)
 
 // ---------------- VimApp ----------------