diff --git a/cmake/external/mklml.cmake b/cmake/external/mklml.cmake
index 51fafb94791dd81dd2833d89a426d23948fe7bde..74f3279831357c21038df133df0f5a432a6dfd20 100644
--- a/cmake/external/mklml.cmake
+++ b/cmake/external/mklml.cmake
@@ -54,7 +54,8 @@ ExternalProject_Add(
     ${EXTERNAL_PROJECT_LOG_ARGS}
     PREFIX                ${MKLML_SOURCE_DIR}
     DOWNLOAD_DIR          ${MKLML_DOWNLOAD_DIR}
-    DOWNLOAD_COMMAND      wget --no-check-certificate -qO- ${MKLML_URL} | tar xz -C ${MKLML_DOWNLOAD_DIR}
+    DOWNLOAD_COMMAND      wget --no-check-certificate ${MKLML_URL} -c -q -O ${MKLML_VER}.tgz 
+                          && tar zxf ${MKLML_VER}.tgz
     DOWNLOAD_NO_PROGRESS  1
     UPDATE_COMMAND        ""
     CMAKE_ARGS            -DCMAKE_INSTALL_PREFIX=${MKLML_INSTALL_ROOT}
diff --git a/paddle/gserver/layers/CostLayer.h b/paddle/gserver/layers/CostLayer.h
index 0ce72ef40a5ac23d20f485eb5b518186d1ec0686..0f655b48eea051c41ce17c0a41189b26188cc866 100644
--- a/paddle/gserver/layers/CostLayer.h
+++ b/paddle/gserver/layers/CostLayer.h
@@ -318,7 +318,9 @@ public:
 
   void forwardImp(Matrix& output, Argument& label, Matrix& cost) override;
 
-  void backwardImp(Matrix& outputValue, Argument& label, Matrix& outputGrad) {}
+  void backwardImp(Matrix& outputValue,
+                   Argument& label,
+                   Matrix& outputGrad) override {}
 };
 
 /**