diff --git a/src/spell.c b/src/spell.c
index dda81d9..83c232c 100644
--- a/src/spell.c
+++ b/src/spell.c
@@ -2073,6 +2073,8 @@
 
     if (len == -1)
 	p = word;
+    else if (len >= MAXWLEN)
+	return;
     else
     {
 	vim_strncpy(buf, word, len);