valgrind it!

enable atom garbage collection.


git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@2055 b08c6af1-5177-4d33-ba66-4b1c6b8b522a

C/exec.c

@@ -1983,9 +1983,11 @@ Yap_InitYaamRegs(void)
   CreepFlag = CalculateStackGap();
   UNLOCK(SignalLock);
   EX = 0L;
-  init_stack(0, NULL, TRUE, NULL);
   /* for slots to work */
   Yap_StartSlots();
+  init_stack(0, NULL, TRUE, NULL);
+  /* the first real choice-point will also have AP=FAIL */ 
+  Yap_StartSlots();
   GlobalArena = TermNil;
   h0var = MkVarTerm();
 #if COROUTINING