title: C++: ifstream getline issue crosscompiling into an OpenWRT distro
body: <p><br>
  I'm trying to compile a simple C++ code inside my customized OpenWRT distro, but I have an error with the <strong>getline</strong> instruction.<br>
  Here it is a snapshot of my code:</p>
  
  <pre><code>#include &lt;stdio.h&gt;                                                                                                                                                                                                                    
  #include &lt;string.h&gt;
  #include &lt;unistd.h&gt;
  #include &lt;string&gt;
  #include &lt;iostream&gt;
  #include &lt;sstream&gt;
  #include &lt;fstream&gt;
  #include &lt;algorithm&gt;
  #include &lt;sys/stat.h&gt;
  ...
  
  ifstream infile(MODEL);
  if (infile.fail())
      return;
  getline(infile, model);
  
  ...
  </code></pre>
  
  <p><strong>I receive this kind of warning (I am compiling with -Werror flag)</strong></p>
  
  <pre><code>In file included from /home/nino/workspace/fmrepo/fm-mt762x/buildroot/staging_dir/target-mipsel_1004kc+dsp_uClibc-0.9.33.2/usr/include/uClibc++/iostream:30:0,
                   from fmsnmpwalk.cpp:5:
  /home/nino/workspace/fmrepo/fm-mt762x/buildroot/staging_dir/target-mipsel_1004kc+dsp_uClibc-0.9.33.2/usr/include/uClibc++/string_iostream: In instantiation of 'std::basic_istream&lt;charT, traits&gt;&amp; std::getline(std::basic_istream&lt;charT, traits&gt;&amp;, std::basic_string&lt;Ch, Tr, A&gt;&amp;, charT) [with charT = char; traits = std::char_traits&lt;char&gt;; Allocator = std::allocator&lt;char&gt;]':
  /home/nino/workspace/fmrepo/fm-mt762x/buildroot/staging_dir/target-mipsel_1004kc+dsp_uClibc-0.9.33.2/usr/include/uClibc++/string_iostream:114:16:   required from 'std::basic_istream&lt;charT, traits&gt;&amp; std::getline(std::basic_istream&lt;charT, traits&gt;&amp;, std::basic_string&lt;Ch, Tr, A&gt;&amp;) [with charT = char; traits = std::char_traits&lt;char&gt;; Allocator = std::allocator&lt;char&gt;]'
  fmsnmpwalk.cpp:47:23:   required from here
  /home/nino/workspace/fmrepo/fm-mt762x/buildroot/staging_dir/target-mipsel_1004kc+dsp_uClibc-0.9.33.2/usr/include/uClibc++/string_iostream:97:11: error: comparison between signed and unsigned integer expressions [-Werror=sign-compare]
    for(i=0;i&lt;n;++i){
             ^
  cc1plus: all warnings being treated as errors
  </code></pre>
  
  <p>I can't understand what is the problem.<br>
  On my OpenWRT distro I am using <strong>gcc 5.x</strong> and <strong>uClibc-0.9.33.2</strong>.<br>
  Any help is appreciated. Thanks!</p>