diff --git a/C/attvar.c b/C/attvar.c
index d883ea86e..7d76840fa 100644
--- a/C/attvar.c
+++ b/C/attvar.c
@@ -111,16 +111,23 @@ CopyAttVar(CELL *orig, CELL ***to_visit_ptr, CELL *res)
     newv->Atts[2*j] = time;
     
     if (IsVarTerm(t)) {
-      RESET_VARIABLE(newv->Atts+(2*j+1));
-    } else if (IsAtomicTerm(t)) {
+      CELL *vt = VarOfTerm(t);
+      if (vt == attv->Atts+(2*j+1)) {
+	RESET_VARIABLE(newv->Atts+(2*j+1));
+      } else {
+	to_visit[0] = vt-1;
+	to_visit[1] = vt;
+	to_visit[2] = newv->Atts+2*j+1;
+	to_visit[3] = vt;
+	to_visit += 4;
+      }
+    } else if (IsVarTerm(t) && IsAtomicTerm(t)) {
       newv->Atts[2*j+1] = t;
     } else {
       to_visit[0] = attv->Atts+2*j;
       to_visit[1] = attv->Atts+2*j+1;
       to_visit[2] = newv->Atts+2*j+1;
       to_visit[3] = (CELL *)(attv->Atts[2*j]);
-      /* fool the system into thinking we had a variable there */
-      attv->Atts[2*j+1] = AbsAppl(H);
       to_visit += 4;
     }
   }
@@ -345,6 +352,8 @@ BuildNewAttVar(Term t, Int i, Term tatt)
     H -= 2;
     t = H[0];
     tatt = H[1];
+    printf("attv is %p\n", attv);
+    attv = (attvar_record *)Yap_ReadTimedVar(DelayedVars);
   }
   time = InitVarTime();
   RESET_VARIABLE(&(attv->Value));
@@ -352,7 +361,7 @@ BuildNewAttVar(Term t, Int i, Term tatt)
   attv->sus_id = attvars_ext;
   for (j = 0; j < NUM_OF_ATTS; j++) {
     attv->Atts[2*j] = time;
-    RESET_VARIABLE(attv->Atts+2*j+1);
+    RESET_VARIABLE(attv->Atts+(2*j+1));
   }
   attv->NS = Yap_UpdateTimedVar(AttsMutableList, (CELL)&(attv->Done));
   Bind((CELL *)t,(CELL)attv);
diff --git a/C/index.c b/C/index.c
index ff9986d87..a6b44539d 100644
--- a/C/index.c
+++ b/C/index.c
@@ -11,8 +11,11 @@
 * File:		index.c							 *
 * comments:	Indexing a Prolog predicate				 *
 *									 *
-* Last rev:     $Date: 2004-04-16 19:27:31 $,$Author: vsc $						 *
+* Last rev:     $Date: 2004-04-20 22:08:23 $,$Author: vsc $						 *
 * $Log: not supported by cvs2svn $
+* Revision 1.85  2004/04/16 19:27:31  vsc
+* more bug fixes
+*
 * Revision 1.84  2004/04/14 19:10:38  vsc
 * expand_clauses: keep a list of clauses to expand
 * fix new trail scheme for multi-assignment variables
@@ -81,6 +84,7 @@ UInt STATIC_PROTO(do_index, (ClauseDef *,ClauseDef *,struct intermediates *,UInt
 UInt STATIC_PROTO(do_compound_index, (ClauseDef *,ClauseDef *,Term *t,struct intermediates *,UInt,UInt,UInt,UInt,int,int,int,CELL *,int));
 UInt STATIC_PROTO(do_dbref_index, (ClauseDef *,ClauseDef *,Term,struct intermediates *,UInt,UInt,int,int,CELL *));
 UInt STATIC_PROTO(do_blob_index, (ClauseDef *,ClauseDef *,Term,struct intermediates *,UInt,UInt,int,int,CELL *));
+/*path_stack_entry *STATIC_PROTO(kill_unsafe_block, (path_stack_entry *,op_numbers,PredEntry *,int,int,ClauseDef *));*/
 
 static UInt labelno;
 
@@ -6087,6 +6091,11 @@ add_to_index(struct intermediates *cint, int first, path_stack_entry *sp, Clause
     case _unlock_lu:
       ipc = NEXTOP(ipc,e);
       break;
+    case _op_fail:
+      while ((--sp)->flag != block_entry);
+      *sp->u.cle.entry_code = cls->Code;
+      ipc = pop_path(&sp, cls, ap);
+      break;
     default:
       sp = kill_unsafe_block(sp, op, ap, first, FALSE, cls);
       ipc = pop_path(&sp, cls, ap);
diff --git a/C/tracer.c b/C/tracer.c
index 09193e2cc..96ac6e6cd 100644
--- a/C/tracer.c
+++ b/C/tracer.c
@@ -130,7 +130,7 @@ low_level_trace(yap_low_level_port port, PredEntry *pred, CELL *args)
 #ifdef COMMENTED
   //  if (vsc_count == 218280)
   //    vsc_xstop = 1;
-  if (vsc_count < 218200) {
+  if (vsc_count < 1468068888) {
     UNLOCK(heap_regs->low_level_trace_lock);
     return;
   }
diff --git a/C/utilpreds.c b/C/utilpreds.c
index b691d82a7..6a51f3660 100644
--- a/C/utilpreds.c
+++ b/C/utilpreds.c
@@ -49,7 +49,7 @@ clean_tr(tr_fr_ptr TR0) {
   if (TR != TR0) {
     do {
       Term p = TrailTerm(--TR);
-	RESET_VARIABLE(p);
+      RESET_VARIABLE(p);
     } while (TR != TR0);
   }
 }
@@ -65,7 +65,6 @@ copy_complex_term(register CELL *pt0, register CELL *pt0_end, CELL *ptf, CELL *H
   CELL *dvars = NULL;
 #endif
   HB = HLow;
-
   to_visit0 = to_visit;
  loop:
   while (pt0 < pt0_end) {
@@ -120,7 +119,7 @@ copy_complex_term(register CELL *pt0, register CELL *pt0_end, CELL *ptf, CELL *H
 	register CELL *ap2;
 	/* store the terms to visit */
 	ap2 = RepAppl(d0);
-	if (ap2 >= HB && ap2 < H) {
+	if (ap2 >= HB && ap2 <= H) {
 	  /* If this is newer than the current term, just reuse */
 	  *ptf++ = d0;
 	  continue;
@@ -185,13 +184,16 @@ copy_complex_term(register CELL *pt0, register CELL *pt0_end, CELL *ptf, CELL *H
       if (IsAttachedTerm((CELL)ptd0)) {
 	/* if unbound, call the standard copy term routine */
 	CELL **bp[1];
-	
+
 	if (dvars == NULL) {
 	  dvars = (CELL *)Yap_ReadTimedVar(DelayedVars);
 	} 	
 	if (ptd0 >= dvars) {
 	  *ptf++ = (CELL) ptd0;
 	} else {
+	  tr_fr_ptr CurTR;
+
+	  CurTR = TR;
 	  bp[0] = to_visit;
 	  HB = HB0;
 	  if (!attas[ExtFromCell(ptd0)].copy_term_op(ptd0, bp, ptf)) {
@@ -199,6 +201,43 @@ copy_complex_term(register CELL *pt0, register CELL *pt0_end, CELL *ptf, CELL *H
 	  }
 	  to_visit = bp[0];
 	  HB = HLow;
+	  if (CurTR != TR) {
+	    /* Problem here is that the attached routine might
+	     *  have changed the list of suspended goals and stored
+	     *  new entries in the trail. This should be quite
+	     *  rare, so for simplicity we just swap cells from
+	     *  bottom and top of Trail, not nice but not worth
+	     *  complicating everything else.
+	     */
+	    CELL *pt1 = (CELL *)TR0;
+	    CELL *pt2 = (CELL *)CurTR;
+	    CELL *pt3 = (CELL *)TR;
+	    if (pt1 == pt2) {
+	      TR0 = TR;
+	    } else {
+	      /* make a backup copy */
+	      while (pt2 < pt3)
+		*((CELL *)TR)++ = *pt2++;
+	      /* reset pointers */
+	      TR = (tr_fr_ptr)pt3;
+	      pt2  = (CELL *)CurTR;
+	      /* now go to old trail */
+	      pt3 = pt1+(pt2-pt1);
+	      /* copy old trail above */
+	      if (pt3 != pt1) {
+		while (pt3 < pt2) {
+		  *pt3++ = *pt1++;
+		}
+	      }
+	      pt1 = (CELL *)TR0;
+	      pt2 = pt1 + (pt3-(CELL *)CurTR);
+	      /* copy new trail below */
+	      while (pt1 < pt2) {
+		*pt1++ = *pt3++;
+	      }
+	      TR0 = (tr_fr_ptr)pt1;
+	    }
+	  }
 	  ptf++;
 	  Bind_Global(ptd0, ptf[-1]);
 	}
diff --git a/pl/boot.yap b/pl/boot.yap
index 66d51ce5f..6370ed42c 100644
--- a/pl/boot.yap
+++ b/pl/boot.yap
@@ -224,7 +224,7 @@ repeat :- '$repeat'.
 '$execute_commands'(V,_,_) :- var(V), !,
 	'$do_error'(instantiation_error,meta_call(V)).
 '$execute_commands'([],_,_) :- !, fail.
-'$execute_commands'([C|_],VL,Con) :- !,
+'$execute_commands'([C|Cs],VL,Con) :- !,
 	(
 	  '$execute_command'(C,VL,Con)
 	;
diff --git a/pl/modules.yap b/pl/modules.yap
index 0944b8d75..4cb358d92 100644
--- a/pl/modules.yap
+++ b/pl/modules.yap
@@ -318,10 +318,12 @@ module(N) :-
 % a meta-call.
 %
 '$expand_goal'(G0, GoalMod, CurMod, G, NM) :-
-	'$meta_expansion'(GoalMod, CurMod, G0, GF, []), !,
-	'$expand_goal2'(GF,GoalMod,G,NM).
-'$expand_goal'(G, GoalMod, _, NG, NM) :-
-	'$expand_goal2'(G, GoalMod, NG, NM).
+	'$expand_goal2'(G0,GoalMod,G1,NM),
+	( '$meta_expansion'(GoalMod, CurMod, G1, GF, []) ->
+		G = GF
+	;
+	        G = G1
+	).
 
 '$expand_goal2'(G, M, NG, NM) :-
 	'$undefined'(G,M),