diff --git a/Dockerfile b/Dockerfile
index 82a08b3a2764841b13a1380647efadb3399fc3ec..8f54b870d594ece33d9c93ea40908668d3ad2f0e 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -28,6 +28,6 @@ RUN apt-get autoremove -y && apt-get clean
 RUN pip install --upgrade pip
 RUN pip install wheel && pip install pre-commit
 RUN ln -s clang-format-5.0 /usr/bin/clang-format
-# RUN cd /tmp && curl -O http://mirrors.neusoft.edu.cn/android/repository/android-ndk-r17b-linux-x86_64.zip
-# RUN cd /opt && unzip /tmp/android-ndk-r17b-linux-x86_64.zip
-# ENV NDK_ROOT /opt/android-ndk-r17b
+RUN cd /tmp && curl -O http://mirrors.neusoft.edu.cn/android/repository/android-ndk-r17b-linux-x86_64.zip
+RUN cd /opt && unzip /tmp/android-ndk-r17b-linux-x86_64.zip
+ENV NDK_ROOT /opt/android-ndk-r17b
diff --git a/src/operators/kernel/central-arm-func/batchnorm_arm_func.h b/src/operators/kernel/central-arm-func/batchnorm_arm_func.h
index 7f02d768b790b5f496ab0eac369fa3a4100ee733..2086265ec6d9d36c5b3a334fad7a5cf66fc01f2b 100644
--- a/src/operators/kernel/central-arm-func/batchnorm_arm_func.h
+++ b/src/operators/kernel/central-arm-func/batchnorm_arm_func.h
@@ -16,6 +16,7 @@ limitations under the License. */
 
 #pragma once
 
+#include <cmath>
 #include "operators/op_param.h"
 
 namespace paddle_mobile {
diff --git a/tools/android-cmake/android.toolchain.cmake b/tools/android-cmake/android.toolchain.cmake
index 4db5cd41b46246f92882f1548290fb87fc915aae..a57d9c102ff65d4c10cc9bd3773ffa4c87e482fa 100644
--- a/tools/android-cmake/android.toolchain.cmake
+++ b/tools/android-cmake/android.toolchain.cmake
@@ -37,7 +37,7 @@
 # ANDROID_DISABLE_FORMAT_STRING_CHECKS
 # ANDROID_CCACHE
 
-cmake_minimum_required(VERSION 3.6.0)
+# cmake_minimum_required(VERSION 3.6.0)
 
 # Inhibit all of CMake's own NDK handling code.
 set(CMAKE_SYSTEM_VERSION 1)