remove warning from MSVC need another round of check

src/io/io.cpp

@@ -1,5 +1,6 @@
 #define _CRT_SECURE_NO_WARNINGS
 #define _CRT_SECURE_NO_DEPRECATE
+#define NOMINMAX
 #include <string>
 #include "./io.h"
 #include "../utils/io.h"

src/io/page_dmatrix-inl.hpp

@@ -165,7 +165,7 @@ class ThreadRowPageIterator: public utils::IIterator<RowBatch> {
   // loader factory for page
   struct Factory {
    public:
-    long file_begin_;
+    size_t file_begin_;
     utils::FileStream fi;
     Factory(void) {}
     inline void SetFile(const utils::FileStream &fi) {

src/io/page_fmatrix-inl.hpp

@@ -138,8 +138,8 @@ class CSCMatrixManager {
     fi_->Seek(col_ptr_[cidx] * sizeof(ColBatch::Entry) + begin_data_);
     utils::Check(fi_->Read(p_data, sizeof(ColBatch::Entry) * len) != 0,
                  "invalid column buffer format");
-    p_page->col_data.push_back(ColBatch::Inst(p_data, len));
-    p_page->col_index.push_back(cidx);
+    p_page->col_data.push_back(ColBatch::Inst(p_data, static_cast<bst_uint>(len)));
+    p_page->col_index.push_back(static_cast<bst_uint>(cidx));
     return true;
   }
   // the following are in memory auxiliary data structure