put chr back to life

git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@2265 b08c6af1-5177-4d33-ba66-4b1c6b8b522a

C/heapgc.c

@@ -3456,15 +3456,15 @@ marking_phase(tr_fr_ptr old_TR, CELL *current_env, yamop *curp, CELL *max)
   cont_top0 = (cont *)db_vec;
 #endif
   cont_top = (cont *)db_vec;
+#ifdef COROUTINING
+  mark_delays(max);
+#endif
   /* These two must be marked first so that our trail optimisation won't lose
      values */
   mark_regs(old_TR);		/* active registers & trail */
   /* active environments */
   mark_environments(current_env, EnvSize(curp), EnvBMap((CELL *)curp));
   mark_choicepoints(B, old_TR, is_gc_very_verbose());	/* choicepoints, and environs  */
-#ifdef COROUTINING
-  mark_delays(max);
-#endif
 #ifdef EASY_SHUNTING
   set_conditionals(sTR);
 #endif

C/tracer.c

@@ -164,8 +164,6 @@ low_level_trace(yap_low_level_port port, PredEntry *pred, CELL *args)
   LOCK(Yap_heap_regs->low_level_trace_lock);
   sc = Yap_heap_regs;
   vsc_count++;
-  if (vsc_count < 67689000LL)
-    return;
 #ifdef THREADS
   Yap_heap_regs->thread_handle[worker_id].thread_inst_count++;
 #endif  

library/rbtrees.yap

@@ -923,7 +923,7 @@ is_rbtree(t(_,T)) :-
 is_rbtree(X,_) :-
 	var(X), !, fail.
 is_rbtree(T,Goal) :-
-	catch(rbtree1(T), msg(S,Args), format(S,Args)).
+	catch(rbtree1(T), msg(S,Args), (once(Goal),format(S,Args))).
 
 %
 % This code checks if a tree is ordered and a rbtree