From 2829696db793dd811ea9da69570e3880a2f8c6b6 Mon Sep 17 00:00:00 2001
From: Vitor Santos Costa <vsc@dcc.fc.up.pt>
Date: Thu, 8 Aug 2013 14:12:29 -0500
Subject: [PATCH] fix bug in term_variables/3 with difference lists

---
 C/utilpreds.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/C/utilpreds.c b/C/utilpreds.c
index 65d6bec55..577d2729b 100644
--- a/C/utilpreds.c
+++ b/C/utilpreds.c
@@ -1825,7 +1825,7 @@ static Term vars_in_complex_term(register CELL *pt0, register CELL *pt0_end, Ter
     Term t2 = Deref(inp);
     if (IsVarTerm(t2)) {
       RESET_VARIABLE(H-1);
-      Yap_unify((CELL)(H-1),ARG2);
+      Yap_unify((CELL)(H-1),inp);
     } else {
       H[-1] = t2;		/* don't need to trail */
     }
@@ -2140,7 +2140,7 @@ static Term attvars_in_complex_term(register CELL *pt0, register CELL *pt0_end,
     Term t2 = Deref(inp);
     if (IsVarTerm(t2)) {
       RESET_VARIABLE(H-1);
-      Yap_unify((CELL)(H-1),ARG2);
+      Yap_unify((CELL)(H-1), t2);
     } else {
       H[-1] = t2;		/* don't need to trail */
     }