fix correctly the bug in coroutining: Yap should join the two goals.

git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@1129 b08c6af1-5177-4d33-ba66-4b1c6b8b522a

C/tracer.c

@@ -120,10 +120,6 @@ low_level_trace(yap_low_level_port port, PredEntry *pred, CELL *args)
   /*  extern int gc_calls; */
 
   vsc_count++;
-  if (vsc_count < 845900)
-    return;
-  if (vsc_count == 845979)
-    jmp_deb(1);
 #ifdef COMMENTED
   //  if (vsc_count == 218280)
   //    vsc_xstop = 1;

pl/corout.yap

@@ -220,7 +220,8 @@ dif(_, _).
 %
 % check if the variable was really bound
 %
-'$redo_freeze'(Done, V, _) :- var(V), !.
+'$redo_freeze'(Done, V, G) :- var(V), !,
+	'$freeze'(V, '$redo_freeze'(Done,V,G)).
 %
 % I can't believe it: we're done and can actually execute our
 % goal. Notice we have to say we are done, otherwise someone else in