diff --git a/C/cdmgr.c b/C/cdmgr.c
index 7a175fdd7..8e50c251a 100644
--- a/C/cdmgr.c
+++ b/C/cdmgr.c
@@ -2908,36 +2908,8 @@ static Int p_clean_up_dead_clauses(USES_REGS1) {
 
 void Yap_HidePred(PredEntry *pe) {
   Prop p0 = AbsPredProp(pe);
-  if (pe->ArityOfPE == 0) {
-    Atom a = (Atom)pe->FunctorOfPred;
 
-    p0 = RepAtom(a)->PropsOfAE;
-    if (p0 == AbsPredProp(pe)) {
-      RepAtom(a)->PropsOfAE = pe->NextOfPE;
-    } else {
-      while (p0->NextOfPE != AbsPredProp(pe))
-        p0 = p0->NextOfPE;
-      if (p0 == NIL)
-        return;
-      p0->NextOfPE = pe->NextOfPE;
-    }
-  } else {
-    Functor funt = pe->FunctorOfPred;
-
-    p0 = funt->PropsOfFE;
-    if (p0 == AbsPredProp(pe)) {
-      funt->PropsOfFE = pe->NextOfPE;
-    } else {
-      while (p0->NextOfPE != AbsPredProp(pe))
-        p0 = p0->NextOfPE;
-      if (p0 == NIL)
-        return;
-      p0->NextOfPE = pe->NextOfPE;
-    }
-  }
-  pe->NextOfPE = HIDDEN_PREDICATES;
-  HIDDEN_PREDICATES = AbsPredProp(pe);
-  pe->PredFlags |= HiddenPredFlag;
+  pe->PredFlags |= (HiddenPredFlag | NoSpyPredFlag | NoTracePredFlag);
 }
 
 static Int /* $system_predicate(P) */
@@ -3022,7 +2994,7 @@ restart_system_pred:
     return false;
   if (EndOfPAEntr(pe))
     return false;
-  pe->PredFlags |= (HiddenPredFlag / NoSpyPredFlag | NoTracePredFlag);
+  pe->PredFlags |= (HiddenPredFlag | NoSpyPredFlag | NoTracePredFlag);
   return true;
 }
 
diff --git a/C/dbase.c b/C/dbase.c
index e7cc30b9e..32d35a09f 100644
--- a/C/dbase.c
+++ b/C/dbase.c
@@ -1876,6 +1876,7 @@ static LogUpdClause *new_lu_db_entry(Term t, PredEntry *pe) {
     cl->ClTimeStart = 0L;
   }
   cl->ClTimeEnd = TIMESTAMP_EOT;
+
 #if MULTIPLE_STACKS
   //  INIT_LOCK(cl->ClLock);
   INIT_CLREF_COUNT(cl);
@@ -2709,6 +2710,8 @@ static PredEntry *new_lu_entry(Term t) {
   }
   pe->ArityOfPE = 3;
   pe->OpcodeOfPred = Yap_opcode(_op_fail);
+  if (CurrentModule == PROLOG_MODULE)
+    pe->PredFlags |= StandardPredFlag;
   pe->cs.p_code.TrueCodeOfPred = pe->CodeOfPred = FAILCODE;
   return pe;
 }
@@ -5107,7 +5110,7 @@ static Int p_dequeue(USES_REGS1) {
   QueueEntry *cur_instance;
   Term Father = Deref(ARG1);
   Int rc;
-  
+
   if (IsVarTerm(Father)) {
     Yap_Error(INSTANTIATION_ERROR, Father, "dequeue");
     return FALSE;
diff --git a/C/stdpreds.c b/C/stdpreds.c
index 3d383ff68..841dbe14f 100755
--- a/C/stdpreds.c
+++ b/C/stdpreds.c
@@ -878,13 +878,20 @@ static Int
 }
 
 static bool valid_prop(Prop p, Term task) {
-  if (RepPredProp(p)->OpcodeOfPred == UNDEF_OPCODE)
+  if ((RepPredProp(p)->PredFlags & HiddenPredFlag) ||
+      (RepPredProp(p)->OpcodeOfPred == UNDEF_OPCODE) ){
     return false;
-  if ((RepPredProp(p)->PredFlags & (HiddenPredFlag | StandardPredFlag))) {
-    return (task == SYSTEM_MODULE || task == TermTrue || IsVarTerm(task));
-  } else {
-    return (task == USER_MODULE || task == TermTrue || IsVarTerm(task));
   }
+  if(task == TermSystem || task == TermProlog)  {
+    return RepPredProp(p)->PredFlags & StandardPredFlag;
+  }
+  if(task == TermUser)  {
+    return !(RepPredProp(p)->PredFlags & StandardPredFlag);
+  }
+  if (IsVarTerm(task)) {
+    return true;
+  }
+  return false;
 }
 
 static PropEntry *followLinkedListOfProps(PropEntry *p, Term task) {
diff --git a/pl/absf.yap b/pl/absf.yap
index aa12815ce..5dc87d98a 100755
--- a/pl/absf.yap
+++ b/pl/absf.yap
@@ -13,7 +13,15 @@
 
 %% @{
 
-/** @defgroup absolute_file_name File Name Resolution
+:- system_module( absf, [absolute_file_name/2,
+        absolute_file_name/3,
+        add_to_path/1,
+        add_to_path/2,
+        path/1,
+        remove_from_path/1], ['$full_filename'/3,
+        '$system_library_directories'/2]).
+
+/** @defgroup absf File Name Resolution
 
    @ingroup builtins
 
@@ -24,14 +32,6 @@
   variables and registry information to search for files.
 
   **/
-:- system_module( absolute_file_name, [absolute_file_name/2,
-        absolute_file_name/3,
-        add_to_path/1,
-        add_to_path/2,
-        path/1,
-        remove_from_path/1], ['$full_filename'/3,
-        '$system_library_directories'/2]).
-
 :- use_system_module( '$_boot', ['$system_catch'/4]).
 
 :- use_system_module( '$_errors', ['$do_error'/2]).
diff --git a/pl/protect.yap b/pl/protect.yap
index 5b890cb65..cdba357d5 100755
--- a/pl/protect.yap
+++ b/pl/protect.yap
@@ -20,14 +20,11 @@ xc/*************************************************************************
 % This protects all code from further changes
 % and also makes it impossible from some predicates to be seen
 '$protect' :-
-    current_atom(Name),
-    '$current_predicate'(Name,M,P,_),
+    '$current_predicate'(Name,M,P,_),riteln(P),
     M \= user,
     functor(P,Name,Arity),
     '$new_system_predicate'(Name,Arity,M),
     sub_atom(Name,0,1,_, '$'),
-    \+ '$visible'(Name),
-    hide_predicate(M:P),
     fail.
 '$protect' :-
     current_atom(Name),
@@ -44,15 +41,15 @@ xc/*************************************************************************
 '$visible'('$dbref').			/* not stream position */
 '$visible'('$stream').			/* not $STREAM */
 '$visible'('$stream_position').		/* not stream position */
-'$visible'('$hacks').			
-'$visible'('$source_location').			
-'$visible'('$messages').		
-'$visible'('$push_input_context').		
-'$visible'('$pop_input_context').		
-'$visible'('$set_source_module').		
-'$visible'('$declare_module').		
-'$visible'('$store_clause').		
-'$visible'('$skip_list').		
+'$visible'('$hacks').
+'$visible'('$source_location').
+'$visible'('$messages').
+'$visible'('$push_input_context').
+'$visible'('$pop_input_context').
+'$visible'('$set_source_module').
+'$visible'('$declare_module').
+'$visible'('$store_clause').
+'$visible'('$skip_list').
 '$visible'('$win_insert_menu_item').
 '$visible'('$set_predicate_attribute').
 '$visible'('$parse_quasi_quotations').
@@ -60,4 +57,3 @@ xc/*************************************************************************
 '$visible'('$qq_open').
 '$visible'('$live').
 '$visible'('$init_prolog').
-