diff --git a/src/eval.c b/src/eval.c
index 9f6db31..b2f4462 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -12786,7 +12786,7 @@
 	    dict_add_nr_str(dict, "group", 0L, syn_id2name(cur->hlg_id));
 	    dict_add_nr_str(dict, "priority", (long)cur->priority, NULL);
 	    dict_add_nr_str(dict, "id", (long)cur->id, NULL);
-# ifdef FEAT_CONCEAL
+# if defined(FEAT_CONCEAL) && defined(FEAT_MBYTE)
 	    if (cur->conceal_char)
 	    {
 		char_u buf[MB_MAXBYTES + 1];
diff --git a/src/version.c b/src/version.c
index 8d32e2a..3fa82ca 100644
--- a/src/version.c
+++ b/src/version.c
@@ -749,6 +749,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1690,
+/**/
     1689,
 /**/
     1688,
diff --git a/src/window.c b/src/window.c
index 9530ef5..c7905ae 100644
--- a/src/window.c
+++ b/src/window.c
@@ -6746,11 +6746,11 @@
     m->match.regprog = regprog;
     m->match.rmm_ic = FALSE;
     m->match.rmm_maxcol = 0;
-#ifdef FEAT_CONCEAL
+# if defined(FEAT_CONCEAL) && defined(FEAT_MBYTE)
     m->conceal_char = 0;
     if (conceal_char != NULL)
 	m->conceal_char = (*mb_ptr2char)(conceal_char);
-#endif
+# endif
 
     /* Set up position matches */
     if (pos_list != NULL)