diff --git a/src/syntax.c b/src/syntax.c
index fcd20c8..4f6ef92 100644
--- a/src/syntax.c
+++ b/src/syntax.c
@@ -6304,11 +6304,10 @@
 	curwin->w_s = (synblock_T *)alloc(sizeof(synblock_T));
 	memset(curwin->w_s, 0, sizeof(synblock_T));
 #ifdef FEAT_SPELL
+	/* TODO: keep the spell checking as it was. */
 	curwin->w_p_spell = FALSE;	/* No spell checking */
 	clear_string_option(&curwin->w_s->b_p_spc);
 	clear_string_option(&curwin->w_s->b_p_spf);
-	vim_regfree(curwin->w_s->b_cap_prog);
-	curwin->w_s->b_cap_prog = NULL;
 	clear_string_option(&curwin->w_s->b_p_spl);
 #endif
     }