title: android-ndk: stoi / stof / stod / to_string is not a member of 'std'
body: <p>I was compiling mxnet(v0.9.3) amalgamation with <strong>android NDK Standalone Toolchain</strong> on Ubuntu 14.04 64bit Desktop but met some errors.
  First error is:</p>
  
  <pre><code>arm-linux-androideabi-g++ -std=c++11 -Wall -O3 -msse2 -Wno-unknown-pragmas -funroll-loops -Iinclude -fPIC -M -MT nnvm.o \
      -I `pwd`/../ -I `pwd`/../include \
      -D__MIN__=0 nnvm.cc &gt; nnvm.d
  arm-linux-androideabi-g++: error: unrecognized command line option '-msse2'
  </code></pre>
  
  <p>When I deleted '-msse2' option and run<code>makefile</code>again, it can compile more but later I met new errors like those:</p>
  
  <pre><code>jni/../mxnet_predict-all.cc:2801:37: error: 'fopen64' was not declared in this scope
  jni/../mxnet_predict-all.cc:21495:14: error: 'stoi' is not a member of 'std'
  jni/../mxnet_predict-all.cc:30077:52: error: 'to_string' is not a member of 'std'
  jni/../mxnet_predict-all.cc:34298:29: error: 'stof' is not a member of 'std'
  jni/../mxnet_predict-all.cc:41383:56: error: 'stod' is not a member of 'std'
  ……
  </code></pre>
  
  <p>What should I do to solve those?</p>
  
  <p>BTW:
  My android-ndk version is android-ndk-r13b.
  To create Standalone Toolchain, I followed those steps:
  <code>
  $ python NDK/build/tools/make_standalone_toolchain.py --arch arm --api 21 --install-dir /tmp/my-android-toolchain</code></p>
  
  <pre><code>export PATH=$PATH:/tmp/my-android-toolchain/bin
  export CXX=arm-linux-androideabi-g++
  export CC=arm-linux-androideabi-gcc
  </code></pre>
  
  <p>More information:<a href="https://github.com/dmlc/mxnet/issues/4888" rel="nofollow noreferrer">https://github.com/dmlc/mxnet/issues/4888</a></p>
  
  <hr>
  
  <p>The #includes of my mxnet_predict-all.cc:</p>
  
  <pre><code>#if defined(__MACH__)
  #include &lt;mach/clock.h&gt;
  #include &lt;mach/mach.h&gt;
  #endif
  
  #if !defined(__WIN32__)
  #include &lt;sys/stat.h&gt;
  #include &lt;sys/types.h&gt;
  
  #if !defined(__ANDROID__) &amp;&amp; (!defined(MSHADOW_USE_SSE) || MSHADOW_USE_SSE == 1)
  #include &lt;emmintrin.h&gt;
  #endif
  
  #endif
  
  #include &lt;algorithm&gt;
  #include &lt;array&gt;
  #include &lt;assert.h&gt;
  #include &lt;atomic&gt;
  #include &lt;cblas.h&gt;
  #include &lt;cctype&gt;
  #include &lt;cfloat&gt;
  #include &lt;chrono&gt;
  #include &lt;climits&gt;
  #include &lt;cmath&gt;
  #include &lt;condition_variable&gt;
  #include &lt;cstddef&gt;
  #include &lt;cstdint&gt;
  #include &lt;cstdio&gt;
  #include &lt;cstdlib&gt;
  #include &lt;cstring&gt;
  #include &lt;ctime&gt;
  #include &lt;deque&gt;
  #include &lt;dirent.h&gt;
  #include &lt;errno.h&gt;
  #include &lt;fstream&gt;
  #include &lt;functional&gt;
  #include &lt;inttypes.h&gt;
  #include &lt;iostream&gt;
  #include &lt;istream&gt;
  #include &lt;limits&gt;
  #include &lt;list&gt;
  #include &lt;map&gt;
  #include &lt;memory&gt;
  #include &lt;mutex&gt;
  #include &lt;new&gt;
  #include &lt;ostream&gt;
  #include &lt;queue&gt;
  #include &lt;random&gt;
  #include &lt;regex&gt;
  #include &lt;sched.h&gt;
  #include &lt;set&gt;
  #include &lt;sstream&gt;
  #include &lt;stdbool.h&gt;
  #include &lt;stddef.h&gt;
  #include &lt;stdexcept&gt;
  #include &lt;stdint.h&gt;
  #include &lt;stdlib.h&gt;
  #include &lt;streambuf&gt;
  #include &lt;string&gt;
  #include &lt;thread&gt;
  #include &lt;time.h&gt;
  #include &lt;tuple&gt;
  #include &lt;type_traits&gt;
  #include &lt;typeindex&gt;
  #include &lt;typeinfo&gt;
  #include &lt;unordered_map&gt;
  #include &lt;unordered_set&gt;
  #include &lt;utility&gt;
  #include &lt;vector&gt;
  </code></pre>