title: fstream does not function in Qt Creator
body: <p>I am new in Qt. I have my project coded in visual C++ 2010 express edition which works totally fine. Then, I want to use .cpp files that I already created in Qt console application (similar to my project in VC++2010). Compiling fails at "ofstream" and "ifstream" with this error:</p>
  
  <pre><code>"no matching function for call to 'std::basic_ofstream&lt;char&gt;::basic_ofstream(std::basic_strinstream&lt;char&gt;::_string_type)'"
  "no matching function for call to 'std::basic_ifstream&lt;char&gt;::basic_ofstream(std::string&amp;)'"
  </code></pre>
  
  <p>I have included fstream to the cpp file as:</p>
  
  <pre><code>#include &lt;QCoreApplication&gt;
  #include &lt;iostream&gt;
  #include &lt;vector&gt;
  #include &lt;string&gt;
  #include &lt;fstream&gt;
  #include &lt;sstream&gt;
  
  using namespace std;
  </code></pre>
  
  <p>and the piece of the code which fails is as follows:</p>
  
  <pre><code>stringstream s1; s1 &lt;&lt; "Estimated_NN_ThrMWh.csv";
  ofstream outF1(s1.str());
  </code></pre>
  
  <p>By the way, I am using "MinGW 4.9.1 32bit" as my compiler. What is the issue and how can I fix it? Thanks for your help.</p>