tdf#129993 broken tables opening LWP file

regression from
    commit e2080e70fe8b085f18e868e46340454720fa94ca
    new compilerplugin returnbyref

The parts that fix this specific bug are in lwprowlayout.cxx and
lwprowlayout.cxx, but fix the other parts I messed up but not
understanding the semantics of assigning to reference variables.

Change-Id: I064cdd108c5b05da6092da0297dc7bcf487c7702
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/87686
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
(cherry picked from commit 0b113d6ebbaf923e11ba576bed2691bb68e95ae6)
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/87717

6 files changed, 80 insertions, 80 deletions

diff --git a/lotuswordpro/source/filter/lwpfnlayout.cxx b/lotuswordpro/source/filter/lwpfnlayout.cxx
index 6dc167ff8dda..f95a1eddb622 100644
--- a/lotuswordpro/source/filter/lwpfnlayout.cxx
+++ b/lotuswordpro/source/filter/lwpfnlayout.cxx
@@ -114,15 +114,15 @@ void LwpFnRowLayout::Read()
 void LwpFnRowLayout::RegisterStyle()
 {
     // register cells' style
-    LwpObjectID& rCellID = GetChildHead();
-    LwpCellLayout * pCellLayout = dynamic_cast<LwpCellLayout *>(rCellID.obj().get());
+    LwpObjectID* pCellID = &GetChildHead();
+    LwpCellLayout * pCellLayout = dynamic_cast<LwpCellLayout *>(pCellID->obj().get());
 
     while(pCellLayout)
     {
         pCellLayout->SetFoundry(m_pFoundry);
         pCellLayout->RegisterStyle();
-        rCellID = pCellLayout->GetNext();
-        pCellLayout = dynamic_cast<LwpCellLayout *>(rCellID.obj().get());
+        pCellID = &pCellLayout->GetNext();
+        pCellLayout = dynamic_cast<LwpCellLayout *>(pCellID->obj().get());
     }
 }
 
@@ -194,15 +194,15 @@ void LwpEndnoteLayout::Read()
 void LwpEndnoteLayout::RegisterStyle()
 {
     // register style of rows
-    LwpObjectID& rRowID = GetChildHead();
-    LwpRowLayout * pRowLayout = dynamic_cast<LwpRowLayout *>(rRowID.obj().get());
+    LwpObjectID* pRowID = &GetChildHead();
+    LwpRowLayout * pRowLayout = dynamic_cast<LwpRowLayout *>(pRowID->obj().get());
     while (pRowLayout)
     {
         pRowLayout->SetFoundry(m_pFoundry);
         pRowLayout->RegisterStyle();
 
-        rRowID = pRowLayout->GetNext();
-        pRowLayout = dynamic_cast<LwpRowLayout *>(rRowID.obj().get());
+        pRowID = &pRowLayout->GetNext();
+        pRowLayout = dynamic_cast<LwpRowLayout *>(pRowID->obj().get());
     }
 }
 
@@ -254,12 +254,12 @@ void LwpEnSuperTableLayout::XFConvert(XFContentContainer * /*pCont*/)
  */
 LwpVirtualLayout* LwpEnSuperTableLayout::GetMainTableLayout()
 {
-    LwpObjectID& rID = GetChildTail();
+    LwpObjectID *pID = &GetChildTail();
 
     LwpVirtualLayout *pPrevLayout = nullptr;
-    while(!rID.IsNull())
+    while(!pID->IsNull())
     {
-        LwpVirtualLayout* pLayout = dynamic_cast<LwpVirtualLayout*>(rID.obj().get());
+        LwpVirtualLayout* pLayout = dynamic_cast<LwpVirtualLayout*>(pID->obj().get());
         if (!pLayout || pLayout == pPrevLayout)
         {
             break;
@@ -268,7 +268,7 @@ LwpVirtualLayout* LwpEnSuperTableLayout::GetMainTableLayout()
         {
             return pLayout;
         }
-        rID = pLayout->GetPrevious();
+        pID = &pLayout->GetPrevious();
         pPrevLayout = pLayout;
     }
 
@@ -312,11 +312,11 @@ void LwpFnSuperTableLayout::XFConvert(XFContentContainer * /*pCont*/)
  */
 LwpVirtualLayout* LwpFnSuperTableLayout::GetMainTableLayout()
 {
-    LwpObjectID& rID = GetChildTail();
+    LwpObjectID *pID = &GetChildTail();
 
-    while(!rID.IsNull())
+    while(pID && !pID->IsNull())
     {
-        LwpVirtualLayout * pLayout = dynamic_cast<LwpVirtualLayout *>(rID.obj().get());
+        LwpVirtualLayout * pLayout = dynamic_cast<LwpVirtualLayout *>(pID->obj().get());
         if(!pLayout)
         {
             break;
@@ -325,7 +325,7 @@ LwpVirtualLayout* LwpFnSuperTableLayout::GetMainTableLayout()
         {
             return pLayout;
         }
-        rID = pLayout->GetPrevious();
+        pID = &pLayout->GetPrevious();
     }
 
     return nullptr;
diff --git a/lotuswordpro/source/filter/lwpfoundry.cxx b/lotuswordpro/source/filter/lwpfoundry.cxx
index 40420d92244c..12226c95255c 100644
--- a/lotuswordpro/source/filter/lwpfoundry.cxx
+++ b/lotuswordpro/source/filter/lwpfoundry.cxx
@@ -216,15 +216,15 @@ LwpBookMark* LwpFoundry::GetBookMark(LwpObjectID objMarker)
     if (!pHeadHolder)
         return nullptr;
 
-    LwpObjectID& rObjID = pHeadHolder->GetHeadID();
-    LwpBookMark* pBookMark = dynamic_cast<LwpBookMark*>(rObjID.obj().get());
+    LwpObjectID* pObjID = &pHeadHolder->GetHeadID();
+    LwpBookMark* pBookMark = dynamic_cast<LwpBookMark*>(pObjID->obj().get());
 
     while (pBookMark)
     {
         if (pBookMark->IsRightMarker(objMarker))
             return pBookMark;
-        rObjID = pBookMark->GetNext();
-        pBookMark = dynamic_cast<LwpBookMark*>(rObjID.obj().get());
+        pObjID = &pBookMark->GetNext();
+        pBookMark = dynamic_cast<LwpBookMark*>(pObjID->obj().get());
     }
     return nullptr;
 }
diff --git a/lotuswordpro/source/filter/lwplayout.cxx b/lotuswordpro/source/filter/lwplayout.cxx
index d9b442268b04..b5c762a9203b 100644
--- a/lotuswordpro/source/filter/lwplayout.cxx
+++ b/lotuswordpro/source/filter/lwplayout.cxx
@@ -382,12 +382,12 @@ bool LwpVirtualLayout::IsStyleLayout()
 */
 LwpVirtualLayout* LwpVirtualLayout::FindChildByType(LWP_LAYOUT_TYPE eType)
 {
-    LwpObjectID& rID = GetChildHead();
+    LwpObjectID *pID = &GetChildHead();
     LwpVirtualLayout* pPrevLayout = nullptr;
 
-    while(!rID.IsNull())
+    while(pID && !pID->IsNull())
     {
-        LwpVirtualLayout * pLayout = dynamic_cast<LwpVirtualLayout *>(rID.obj().get());
+        LwpVirtualLayout * pLayout = dynamic_cast<LwpVirtualLayout *>(pID->obj().get());
         if (!pLayout)
             break;
 
@@ -402,7 +402,7 @@ LwpVirtualLayout* LwpVirtualLayout::FindChildByType(LWP_LAYOUT_TYPE eType)
         if (pLayout->GetLayoutType() == eType)
             return pLayout;
 
-        rID = pLayout->GetNext();
+        pID = &pLayout->GetNext();
     }
 
     return nullptr;
diff --git a/lotuswordpro/source/filter/lwprowlayout.cxx b/lotuswordpro/source/filter/lwprowlayout.cxx
index 4648d1ec00e4..287f8de65434 100644
--- a/lotuswordpro/source/filter/lwprowlayout.cxx
+++ b/lotuswordpro/source/filter/lwprowlayout.cxx
@@ -93,8 +93,8 @@ LwpRowLayout::~LwpRowLayout()
  */
 void LwpRowLayout::SetRowMap()
 {
-    LwpObjectID& rCellID= GetChildHead();
-    LwpCellLayout * pCellLayout = dynamic_cast<LwpCellLayout *>(rCellID.obj().get());
+    LwpObjectID *pCellID= &GetChildHead();
+    LwpCellLayout * pCellLayout = dynamic_cast<LwpCellLayout *>(pCellID->obj().get());
 
     std::set<LwpCellLayout*> aSeen;
     while(pCellLayout)
@@ -102,8 +102,8 @@ void LwpRowLayout::SetRowMap()
         aSeen.insert(pCellLayout);
         pCellLayout->SetCellMap();
 
-        rCellID = pCellLayout->GetNext();
-        pCellLayout = dynamic_cast<LwpCellLayout *>(rCellID.obj().get());
+        pCellID = &pCellLayout->GetNext();
+        pCellLayout = dynamic_cast<LwpCellLayout *>(pCellID->obj().get());
         if (aSeen.find(pCellLayout) != aSeen.end())
             throw std::runtime_error("loop in conversion");
     }
@@ -137,8 +137,8 @@ void LwpRowLayout::RegisterStyle()
         pTableLayout->GetTable();
     }
     // register cells' style
-    LwpObjectID& rCellID= GetChildHead();
-    LwpCellLayout * pCellLayout = dynamic_cast<LwpCellLayout *>(rCellID.obj().get());
+    LwpObjectID *pCellID= &GetChildHead();
+    LwpCellLayout * pCellLayout = dynamic_cast<LwpCellLayout *>(pCellID->obj().get());
 
     std::set<LwpCellLayout*> aSeen;
     while (pCellLayout)
@@ -147,8 +147,8 @@ void LwpRowLayout::RegisterStyle()
 
         pCellLayout->SetFoundry(m_pFoundry);
         pCellLayout->RegisterStyle();
-        rCellID = pCellLayout->GetNext();
-        pCellLayout = dynamic_cast<LwpCellLayout *>(rCellID.obj().get());
+        pCellID = &pCellLayout->GetNext();
+        pCellLayout = dynamic_cast<LwpCellLayout *>(pCellID->obj().get());
 
         if (aSeen.find(pCellLayout) != aSeen.end())
             throw std::runtime_error("loop in conversion");
@@ -387,8 +387,8 @@ void LwpRowLayout::ConvertCommonRow(rtl::Reference<XFTable> const & pXFTable, sa
     for (sal_uInt8 i = nStartCol; i < nEndCol ; i++)
     {
         // add row to table
-        LwpObjectID& rCellID= GetChildHead();
-        LwpCellLayout * pCellLayout = dynamic_cast<LwpCellLayout *>(rCellID.obj().get());
+        LwpObjectID *pCellID= &GetChildHead();
+        LwpCellLayout * pCellLayout = dynamic_cast<LwpCellLayout *>(pCellID->obj().get());
         nCellStartCol = i;//mark the begin position of cell
         nCellEndCol = i;//mark the end position of cell
         rtl::Reference<XFCell> xCell;
@@ -405,8 +405,8 @@ void LwpRowLayout::ConvertCommonRow(rtl::Reference<XFTable> const & pXFTable, sa
                 xCell = pCellLayout->DoConvertCell(pTable->GetObjectID(),crowid,i);
                 break;
             }
-            rCellID = pCellLayout->GetNext();
-            pCellLayout = dynamic_cast<LwpCellLayout *>(rCellID.obj().get());
+            pCellID = &pCellLayout->GetNext();
+            pCellLayout = dynamic_cast<LwpCellLayout *>(pCellID->obj().get());
         }
         if (!pCellLayout)
         {
@@ -436,8 +436,8 @@ void LwpRowLayout::ConvertCommonRow(rtl::Reference<XFTable> const & pXFTable, sa
  */
 void LwpRowLayout::CollectMergeInfo()
 {
-    LwpObjectID& rCellID= GetChildHead();
-    LwpCellLayout * pCellLayout = dynamic_cast<LwpCellLayout *>(rCellID.obj().get());
+    LwpObjectID *pCellID= &GetChildHead();
+    LwpCellLayout * pCellLayout = dynamic_cast<LwpCellLayout *>(pCellID->obj().get());
 
     while(pCellLayout)
     {
@@ -446,8 +446,8 @@ void LwpRowLayout::CollectMergeInfo()
             LwpConnectedCellLayout* pConnCell = static_cast<LwpConnectedCellLayout*>(pCellLayout);
             m_ConnCellList.push_back(pConnCell);
         }
-        rCellID = pCellLayout->GetNext();
-        pCellLayout = dynamic_cast<LwpCellLayout *>(rCellID.obj().get());
+        pCellID = &pCellLayout->GetNext();
+        pCellLayout = dynamic_cast<LwpCellLayout *>(pCellID->obj().get());
     }
 }
 /**
diff --git a/lotuswordpro/source/filter/lwptablelayout.cxx b/lotuswordpro/source/filter/lwptablelayout.cxx
index e1647dd34511..448599e5b2c5 100644
--- a/lotuswordpro/source/filter/lwptablelayout.cxx
+++ b/lotuswordpro/source/filter/lwptablelayout.cxx
@@ -109,11 +109,11 @@ void LwpSuperTableLayout::Read()
  */
 LwpTableLayout* LwpSuperTableLayout::GetTableLayout()
 {
-    LwpObjectID& rID = GetChildTail();
+    LwpObjectID *pID = &GetChildTail();
 
-    while(!rID.IsNull())
+    while(pID && !pID->IsNull())
     {
-        LwpLayout* pLayout = dynamic_cast<LwpLayout*>(rID.obj().get());
+        LwpLayout* pLayout = dynamic_cast<LwpLayout*>(pID->obj().get());
         if (!pLayout)
         {
             break;
@@ -122,7 +122,7 @@ LwpTableLayout* LwpSuperTableLayout::GetTableLayout()
         {
             return dynamic_cast<LwpTableLayout *>(pLayout);
         }
-        rID = pLayout->GetPrevious();
+        pID = &pLayout->GetPrevious();
     }
 
     return nullptr;
@@ -133,11 +133,11 @@ LwpTableLayout* LwpSuperTableLayout::GetTableLayout()
  */
 LwpTableHeadingLayout* LwpSuperTableLayout::GetTableHeadingLayout()
 {
-    LwpObjectID& rID = GetChildTail();
+    LwpObjectID *pID = &GetChildTail();
 
-    while(!rID.IsNull())
+    while(pID && !pID->IsNull())
     {
-        LwpLayout * pLayout = dynamic_cast<LwpLayout *>(rID.obj().get());
+        LwpLayout * pLayout = dynamic_cast<LwpLayout *>(pID->obj().get());
         if (!pLayout)
         {
             break;
@@ -147,7 +147,7 @@ LwpTableHeadingLayout* LwpSuperTableLayout::GetTableHeadingLayout()
         {
             return dynamic_cast<LwpTableHeadingLayout *>(pLayout);
         }
-        rID = pLayout->GetPrevious();
+        pID = &pLayout->GetPrevious();
     }
 
     return nullptr;
@@ -229,8 +229,8 @@ double LwpSuperTableLayout::GetTableWidth()
 
         for(sal_uInt16 i =0; i< nCol; i++)
         {
-            LwpObjectID& rColumnID = pTableLayout->GetColumnLayoutHead();
-            LwpColumnLayout * pColumnLayout = dynamic_cast<LwpColumnLayout *>(rColumnID.obj().get());
+            LwpObjectID *pColumnID = &pTableLayout->GetColumnLayoutHead();
+            LwpColumnLayout * pColumnLayout = dynamic_cast<LwpColumnLayout *>(pColumnID->obj().get());
             double dColumnWidth = dDefaultWidth;
             std::set<LwpColumnLayout*> aSeen;
             while (pColumnLayout)
@@ -241,8 +241,8 @@ double LwpSuperTableLayout::GetTableWidth()
                     dColumnWidth = pColumnLayout->GetWidth();
                     break;
                 }
-                rColumnID = pColumnLayout->GetNext();
-                pColumnLayout = dynamic_cast<LwpColumnLayout *>(rColumnID.obj().get());
+                pColumnID = &pColumnLayout->GetNext();
+                pColumnLayout = dynamic_cast<LwpColumnLayout *>(pColumnID->obj().get());
                 if (aSeen.find(pColumnLayout) != aSeen.end())
                     throw std::runtime_error("loop in conversion");
             }
@@ -450,8 +450,8 @@ void LwpTableLayout::TraverseTable()
     m_WordProCellsMap.insert(m_WordProCellsMap.end(), nCount, m_pDefaultCellLayout);
 
     // set value
-    LwpObjectID& rRowID = GetChildHead();
-    LwpRowLayout * pRowLayout = dynamic_cast<LwpRowLayout *>(rRowID.obj().get());
+    LwpObjectID* pRowID = &GetChildHead();
+    LwpRowLayout * pRowLayout = dynamic_cast<LwpRowLayout *>(pRowID->obj().get());
     std::set<LwpRowLayout*> aSeen;
     while (pRowLayout)
     {
@@ -464,8 +464,8 @@ void LwpTableLayout::TraverseTable()
         pRowLayout->CollectMergeInfo();
         // end for 's analysis
 
-        rRowID = pRowLayout->GetNext();
-        pRowLayout = dynamic_cast<LwpRowLayout *>(rRowID.obj().get());
+        pRowID = &pRowLayout->GetNext();
+        pRowLayout = dynamic_cast<LwpRowLayout *>(pRowID->obj().get());
         if (aSeen.find(pRowLayout) != aSeen.end())
             throw std::runtime_error("loop in conversion");
     }
@@ -569,8 +569,8 @@ void LwpTableLayout::RegisterColumns()
 
     // Get total width of justifiable columns
     // NOTICE: all default columns are regarded as justifiable columns
-    LwpObjectID& rColumnID = GetColumnLayoutHead();
-    LwpColumnLayout * pColumnLayout = dynamic_cast<LwpColumnLayout *>(rColumnID.obj().get());
+    LwpObjectID* pColumnID = &GetColumnLayoutHead();
+    LwpColumnLayout * pColumnLayout = dynamic_cast<LwpColumnLayout *>(pColumnID->obj().get());
     std::set<LwpColumnLayout*> aSeen;
     while (pColumnLayout)
     {
@@ -589,8 +589,8 @@ void LwpTableLayout::RegisterColumns()
             nJustifiableColumn --;
         }
 
-        rColumnID = pColumnLayout->GetNext();
-        pColumnLayout = dynamic_cast<LwpColumnLayout *>(rColumnID.obj().get());
+        pColumnID = &pColumnLayout->GetNext();
+        pColumnLayout = dynamic_cast<LwpColumnLayout *>(pColumnID->obj().get());
 
         if (aSeen.find(pColumnLayout) != aSeen.end())
             throw std::runtime_error("loop in conversion");
@@ -670,15 +670,15 @@ void LwpTableLayout::RegisterRows()
     m_DefaultRowStyleName =  pXFStyleManager->AddStyle(std::move(xRowStyle)).m_pStyle->GetStyleName();
 
     // register style of rows
-    LwpObjectID& rRowID = GetChildHead();
-    LwpRowLayout * pRowLayout = dynamic_cast<LwpRowLayout *>(rRowID.obj().get());
+    LwpObjectID * pRowID = &GetChildHead();
+    LwpRowLayout * pRowLayout = dynamic_cast<LwpRowLayout *>(pRowID->obj().get());
     while (pRowLayout)
     {
         pRowLayout->SetFoundry(m_pFoundry);
         pRowLayout->RegisterStyle();
 
-        rRowID = pRowLayout->GetNext();
-        pRowLayout = dynamic_cast<LwpRowLayout *>(rRowID.obj().get());
+        pRowID = &pRowLayout->GetNext();
+        pRowLayout = dynamic_cast<LwpRowLayout *>(pRowID->obj().get());
     }
 }
 /**
@@ -1274,8 +1274,8 @@ void LwpTableLayout::ConvertColumn(rtl::Reference<XFTable> const & pXFTable, sal
     for (sal_uInt32 iLoop = 0; iLoop < static_cast<sal_uInt32>(nEndCol)-nStartCol; ++iLoop)
     {
         // add row to table
-        LwpObjectID& rColID = GetColumnLayoutHead();
-        LwpColumnLayout * pColumnLayout = dynamic_cast<LwpColumnLayout *>(rColID.obj().get());
+        LwpObjectID *pColID = &GetColumnLayoutHead();
+        LwpColumnLayout * pColumnLayout = dynamic_cast<LwpColumnLayout *>(pColID->obj().get());
         while (pColumnLayout)
         {
             if (pColumnLayout->GetColumnID() == (iLoop+nStartCol))
@@ -1283,8 +1283,8 @@ void LwpTableLayout::ConvertColumn(rtl::Reference<XFTable> const & pXFTable, sal
                 pXFTable->SetColumnStyle(iLoop+1,  pColumnLayout->GetStyleName());
                 break;
             }
-            rColID = pColumnLayout->GetNext();
-            pColumnLayout = dynamic_cast<LwpColumnLayout *>(rColID.obj().get());
+            pColID = &pColumnLayout->GetNext();
+            pColumnLayout = dynamic_cast<LwpColumnLayout *>(pColID->obj().get());
         }
         if (!pColumnLayout)
         {
@@ -1417,15 +1417,15 @@ XFCell* LwpTableLayout::GetCellsMap(sal_uInt16 nRow,sal_uInt8 nCol)
  */
  LwpRowLayout* LwpTableLayout::GetRowLayout(sal_uInt16 nRow)
 {
-    LwpObjectID& rRowID = GetChildHead();
-    LwpRowLayout * pRowLayout = dynamic_cast<LwpRowLayout *>(rRowID.obj().get());
+    LwpObjectID *pRowID = &GetChildHead();
+    LwpRowLayout * pRowLayout = dynamic_cast<LwpRowLayout *>(pRowID->obj().get());
     while (pRowLayout)
     {
         if(pRowLayout->GetRowID() == nRow)
             return pRowLayout;
 
-        rRowID = pRowLayout->GetNext();
-        pRowLayout = dynamic_cast<LwpRowLayout *>(rRowID.obj().get());
+        pRowID = &pRowLayout->GetNext();
+        pRowLayout = dynamic_cast<LwpRowLayout *>(pRowID->obj().get());
     }
     return nullptr;
 }
diff --git a/lotuswordpro/source/filter/lwptoc.cxx b/lotuswordpro/source/filter/lwptoc.cxx
index 89ab770e4726..56d47abffc93 100644
--- a/lotuswordpro/source/filter/lwptoc.cxx
+++ b/lotuswordpro/source/filter/lwptoc.cxx
@@ -393,8 +393,8 @@ sal_uInt16 LwpTocSuperLayout::GetSeparatorType(sal_uInt16 index)
  */
 LwpTocLevelData * LwpTocSuperLayout::GetSearchLevelPtr(sal_uInt16 index)
 {
-    LwpObjectID& rID = m_SearchItems.GetHead();
-    LwpTocLevelData * pObj = dynamic_cast<LwpTocLevelData *>(rID.obj().get());
+    LwpObjectID * pID = &m_SearchItems.GetHead(); // not necessary to check pID NULL or not
+    LwpTocLevelData * pObj = dynamic_cast<LwpTocLevelData *>(pID->obj().get());
 
     while(pObj)
     {
@@ -403,8 +403,8 @@ LwpTocLevelData * LwpTocSuperLayout::GetSearchLevelPtr(sal_uInt16 index)
             return pObj;
         }
 
-        rID = pObj->GetNext();
-        pObj = dynamic_cast<LwpTocLevelData *>(rID.obj().get());
+        pID = &pObj->GetNext(); // not necessary to check pID NULL or not
+        pObj = dynamic_cast<LwpTocLevelData *>(pID->obj().get());
     }
 
     return nullptr;
@@ -417,8 +417,8 @@ LwpTocLevelData * LwpTocSuperLayout::GetSearchLevelPtr(sal_uInt16 index)
  */
 LwpTocLevelData * LwpTocSuperLayout::GetNextSearchLevelPtr(sal_uInt16 index, LwpTocLevelData * pCurData)
 {
-    LwpObjectID& rID = pCurData->GetNext();
-    LwpTocLevelData * pObj = dynamic_cast<LwpTocLevelData *>(rID.obj().get());
+    LwpObjectID * pID = &pCurData->GetNext();
+    LwpTocLevelData * pObj = dynamic_cast<LwpTocLevelData *>(pID->obj().get());
 
     while(pObj)
     {
@@ -427,8 +427,8 @@ LwpTocLevelData * LwpTocSuperLayout::GetNextSearchLevelPtr(sal_uInt16 index, Lwp
             return pObj;
         }
 
-        rID = pObj->GetNext();
-        pObj = dynamic_cast<LwpTocLevelData *>(rID.obj().get());
+        pID = &pObj->GetNext(); // not necessary to check pID NULL or not
+        pObj = dynamic_cast<LwpTocLevelData *>(pID->obj().get());
     }
 
     return nullptr;