diff --git a/src/vim.h b/src/vim.h
index d9bd51b..bff49be 100644
--- a/src/vim.h
+++ b/src/vim.h
@@ -1571,6 +1571,9 @@
  */
 #define MAXMAPLEN   50
 
+// maximum length of a function name, including SID and NUL
+#define MAX_FUNC_NAME_LEN   200
+
 // Size in bytes of the hash used in the undo file.
 #define UNDO_HASH_SIZE 32