diff --git a/src/spell.c b/src/spell.c
index 5a7720f..2581a5e 100644
--- a/src/spell.c
+++ b/src/spell.c
@@ -3829,7 +3829,7 @@
 			    c = *ws;
 			if (strstr((char *)s, "^^") != NULL)
 			{
-			    if (c != NUL)
+			    if (c != NUL && reslen < MAXWLEN)
 				wres[reslen++] = c;
 			    mch_memmove(word, word + i + 1,
 				       sizeof(int) * (wordlen - (i + 1) + 1));