From 61321e47393ca0586c28c683ed1104dc748ba2d3 Mon Sep 17 00:00:00 2001
From: Przemyslaw Czerpak <druzus@priv.onet.pl>
Date: Tue, 11 Jul 2006 12:21:22 +0000
Subject: [PATCH] 2006-07-11 14:20 UTC+0200 Przemyslaw Czerpak
 (druzus/at/priv.onet.pl)   * harbour/source/vm/estack.c     * minor
 optimizations

  * harbour/source/vm/itemapi.c
    * make hb_itemClear() safe for not allocated stack items
---
 harbour/ChangeLog           |  7 +++++++
 harbour/source/vm/estack.c  | 13 +++++++++++--
 harbour/source/vm/itemapi.c | 12 ++++++++++--
 3 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/harbour/ChangeLog b/harbour/ChangeLog
index c154be38c8..4e0417c383 100644
--- a/harbour/ChangeLog
+++ b/harbour/ChangeLog
@@ -8,6 +8,13 @@
    2002-12-01 13:30 UTC+0100 Foo Bar <foo.bar@foobar.org>
 */
 
+   * doc/en/rddmisc.txt
+   * doc/en/rdddb.txt
+     ! Fix the sample for AFIELDS()
+     * Mark AFIELDS() as obsolete
+
+2006-07-11 14:20 UTC+0200 Przemyslaw Czerpak (druzus/at/priv.onet.pl)
+  * harbour/source/vm/estack.c
     * minor optimizations
 
   * harbour/source/vm/itemapi.c
diff --git a/harbour/source/vm/estack.c b/harbour/source/vm/estack.c
index 667a868a77..d14026136c 100644
--- a/harbour/source/vm/estack.c
+++ b/harbour/source/vm/estack.c
@@ -221,8 +221,13 @@ void hb_stackInit( void )
 void hb_stackRemove( LONG lUntilPos )
 {
    HB_ITEM_PTR * pEnd = hb_stack.pItems + lUntilPos;
+
    while( hb_stack.pPos > pEnd )
-      hb_stackPop();
+   {
+      --hb_stack.pPos;
+      if( HB_IS_COMPLEX( * hb_stack.pPos ) )
+         hb_itemClear( * hb_stack.pPos );
+   }
 }
 
 HB_ITEM_PTR hb_stackNewFrame( HB_STACK_STATE * pStack, USHORT uiParams )
@@ -251,7 +256,11 @@ HB_ITEM_PTR hb_stackNewFrame( HB_STACK_STATE * pStack, USHORT uiParams )
 void hb_stackOldFrame( HB_STACK_STATE * pStack )
 {
    while( hb_stack.pPos > hb_stack.pBase )
-      hb_stackPop();
+   {
+      --hb_stack.pPos;
+      if( HB_IS_COMPLEX( * hb_stack.pPos ) )
+         hb_itemClear( * hb_stack.pPos );
+   }
 
    hb_stack.pBase = hb_stack.pItems + pStack->lBaseItem;
    hb_stack.iStatics = pStack->iStatics;
diff --git a/harbour/source/vm/itemapi.c b/harbour/source/vm/itemapi.c
index 2fb17a961a..93fa9d2e8a 100644
--- a/harbour/source/vm/itemapi.c
+++ b/harbour/source/vm/itemapi.c
@@ -1274,9 +1274,17 @@ HB_EXPORT void hb_itemClear( PHB_ITEM pItem )
    }
    else if( HB_IS_ENUM( pItem ) ) /* FOR EACH control variable */
    {
+      /*
+       * pItem->item.asEnum.valuePtr is intentionally assigned to pValue to
+       * avoid possible problems when pItem is stack item just freed which
+       * can be overwritten if hb_itemRelease( pItem->item.asEnum.basePtr )
+       * activate .prg destructor [druzus]
+       */
+      PHB_ITEM pValue = pItem->item.asEnum.valuePtr;
+
       hb_itemRelease( pItem->item.asEnum.basePtr );
-      if( pItem->item.asEnum.valuePtr )
-         hb_itemRelease( pItem->item.asEnum.valuePtr );
+      if( pValue )
+         hb_itemRelease( pValue );
    }
 
 #if defined( HB_FM_STATISTICS ) && defined( HB_PARANOID_MEM_CHECK )