是什么让这个头文件慢了 VS2005 的爬行?(IntelliSense 无罪?)

To Reproduce:
Using Visual Studio 2005, Create a new "Win32 Console Application" with the default settings (i.e: using precompiled headers). Add the following code to the cpp file. (Extract 'consthashmacro.h' into the source directory (available from the zip file at Chris Savoie's site)

#include "stdafx.h"

#define CONSTHASH(s) ((s)[0])
//#include "consthashmacro.h"

void Send(long hash, long value)
{
   printf("Sending %x %x
", hash, value);
}

#define QQuot_(x) #x
#define QQuote(x) QQuot_(x)
#define Debug_Print(s, v) (Send( CONSTHASH(QQuote(__LINE__)##s), *((long*)&(v))))
int _tmain(int argc, _TCHAR* argv[])
{
       int i = __LINE__;
       float f= 3.14f;
       Debug_Print("This is a test %d", i);

       i++;
       Debug_Print("This is a test %d", i);
       Debug_Print("This was test %f", f);

    return 0;
}

当我用它下面的包含行替换 #define CONSTHASH 时，性能会变慢.