diff --git a/src/Native/LdaNative/lda_engine.cpp b/src/Native/LdaNative/lda_engine.cpp
index e6e9838f86..005fe9f778 100644
--- a/src/Native/LdaNative/lda_engine.cpp
+++ b/src/Native/LdaNative/lda_engine.cpp
@@ -167,7 +167,7 @@ namespace lda {
         CTimer tmDebug(true);
         CheckFunction(0, tmDebug, "enter initializeBeforeTrain", false);
         //allocate model memory from the data preloaded
-        AllocateModelMemory(data_block_);
+        AllocateModelMemory(*data_block_);
         CheckFunction(0, tmDebug, "allocate model memory", false);
 
         double alloc_start = lda::get_time();
@@ -676,7 +676,7 @@ namespace lda {
         data_block_->Allocate(num_document, corpus_size);
     }
 
-    void LdaEngine::AllocateModelMemory(const LDADataBlock* data_block)
+    void LdaEngine::AllocateModelMemory(const LDADataBlock& data_block)
     {
         model_block_->InitFromDataBlock(data_block, V_, K_);
 
diff --git a/src/Native/LdaNative/lda_engine.hpp b/src/Native/LdaNative/lda_engine.hpp
index a87bcbed73..acda354941 100644
--- a/src/Native/LdaNative/lda_engine.hpp
+++ b/src/Native/LdaNative/lda_engine.hpp
@@ -52,7 +52,7 @@ namespace lda {
         void InitializeBeforeTest();
         bool InitializeBeforeTrain();
         void AllocateDataMemory(int num_document, int64_t corpus_size);
-        void AllocateModelMemory(const LDADataBlock* data_block); //in this case, model memory is allocated according to the datablock;
+        void AllocateModelMemory(const LDADataBlock& data_block); //in this case, model memory is allocated according to the datablock;
         void AllocateModelMemory(int num_vocabs, int num_topics, int64_t nonzero_num);
         void AllocateModelMemory(int num_vocabs, int num_topics, int64_t mem_block_size, int64_t alias_mem_block_size);
         void SetAlphaSum(float avgDocLength); //alphasum parameter is set by avgdoclength * alpha
diff --git a/src/Native/LdaNative/model_block.cpp b/src/Native/LdaNative/model_block.cpp
index 9a65317893..ce498a3860 100644
--- a/src/Native/LdaNative/model_block.cpp
+++ b/src/Native/LdaNative/model_block.cpp
@@ -353,12 +353,12 @@ namespace lda
         cout << "alias_mem_block_size = " << sizeof(alias_mem_block_size_) << endl;
     }
 
-    void LDAModelBlock::InitFromDataBlock(const LDADataBlock *data_block, int32_t num_vocabs, int32_t num_topics)
+    void LDAModelBlock::InitFromDataBlock(const LDADataBlock &data_block, int32_t num_vocabs, int32_t num_topics)
     {
         num_vocabs_ = num_vocabs;
         num_topics_ = num_topics;
 
-        int32_t doc_num = data_block->num_documents();
+        int32_t doc_num = data_block.num_documents();
         dict_ = new WordEntry[num_vocabs_];
         for (int i = 0; i < num_vocabs_; ++i)
         {
@@ -367,7 +367,7 @@ namespace lda
 
         for (int i = 0; i < doc_num; ++i)
         {
-            shared_ptr<LDADocument> doc = data_block->GetOneDoc(i);
+            shared_ptr<LDADocument> doc = data_block.GetOneDoc(i);
             int32_t doc_size = doc->size();
             for (int j = 0; j < doc_size; ++j)
             {
diff --git a/src/Native/LdaNative/model_block.h b/src/Native/LdaNative/model_block.h
index 850c32e70f..a555a42199 100644
--- a/src/Native/LdaNative/model_block.h
+++ b/src/Native/LdaNative/model_block.h
@@ -45,7 +45,7 @@ namespace lda
         void Init(int32_t num_vocabs, int32_t num_topics, int64_t nonzero_num);
         void Init(int32_t num_vocabs, int32_t num_topics, int64_t mem_block_size, int64_t alias_mem_block_size);
 
-        void InitFromDataBlock(const LDADataBlock *data_block, int32_t num_vocabs, int32_t num_topics);
+        void InitFromDataBlock(const LDADataBlock &data_block, int32_t num_vocabs, int32_t num_topics);
 
         void GetModelStat(int64_t &mem_block_size, int64_t &alias_mem_block_size);