From 661b9c3b7dc9df4c86a20e774901bf4b500c9a87 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?V=C3=ADtor=20Santos=20Costa=20II?= <vsc@dcc.fc.up.pt>
Date: Tue, 13 Apr 2010 00:31:25 +0100
Subject: [PATCH] protect base choice-point from nasty cutting.

---
 C/c_interface.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/C/c_interface.c b/C/c_interface.c
index df5a6dfb4..63b5490e8 100644
--- a/C/c_interface.c
+++ b/C/c_interface.c
@@ -1943,7 +1943,7 @@ YAP_RestartGoal(void)
 {
   int out;
   BACKUP_MACHINE_REGS();
-  
+
   if (Yap_AllowRestart) {
     P = (yamop *)FAILCODE;
     do_putcf = myputc;
@@ -2023,7 +2023,9 @@ YAP_PruneGoal(void)
     B = B->cp_b;
   }
   Yap_TrimTrail();
-  B = B->cp_b;
+  /* make sure that we do not destroy the guard choice-point */
+  if (Yap_op_from_opcode(B->cp_ap->opc) != _Nstop)
+    B = B->cp_b;
 
   RECOVER_B();
 }
@@ -2619,6 +2621,7 @@ YAP_Reset(void)
   }
   /* reinitialise the engine */
   Yap_InitYaamRegs();
+  Yap_Initialised = TRUE;
 
   RECOVER_MACHINE_REGS();
   return(TRUE);