title: error C2732: linkage specification contradicts earlier specification for 'log'
body: <p>I wrote some functions,and complied it to a dll module .In my header file as followed:</p>
  
  <pre><code>#ifndef GET_DATAFEED_FORKDB_H
  #define GET_DATAFEED_FORKDB_H
  
  #include "..\include\stdafx.h"
  #include &lt;windows.h&gt;
  
  #include "..\include\TDFAPI.h"
  #include "..\include\TDFAPIStruct.h"
  #include "..\include\PathHelper.h"
  #include "..\include\ConfigSettings.h"
  
  // some helper functions
  // ....
  
  extern "C" void openConnect();
  extern "C" void closeConnect();
  
  #endif 
  </code></pre>
  
  <p>However,when I used Visual Studio 2013 Professional to compile it, i got some errors:</p>
  
  <pre><code>F:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\math.h(501) :
    error C2732: linkage specification contradicts earlier specification for  'log'
  F:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\math.h(501) : 
   see declaration of 'log'
  F:\Program Files (x86)\Microsoft Visual Studio12.0\VC\INCLUDE\xtgmath.h(104)
    :error C2732: linkage specification 
    contradicts earlier specification for 'log'
  F:\Program Files (x86)\Microsoft Visual Studio12.0\VC\INCLUDE\xtgmath.h(104)
    : see declaration of 'log'
  F:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\xlocale(337)
    : warning C4530: C++ exception handler used, but unwind semantics are not 
     enabled. Specify /EHsc
  </code></pre>
  
  <p>I have not use math method. so I tried to use <a href="https://msdn.microsoft.com/en-us/library/726yhbsw.aspx" rel="nofollow">this method</a> to solve it, but it did not work. The included head files can't not modified, I also tried use this method:</p>
  
  <pre><code> extern "C" {
      #include "..\include\TDFAPI.h"
      #include "..\include\TDFAPIStruct.h"
      #include "..\include\k.h"
      #include "..\include\PathHelper.h"
      #include "..\include\ConfigSettings.h"
    }
  </code></pre>
  
  <p>,what's worse, it occurred more errors.</p>