How to use VC_EXTRALEAN and WIN32_LEAN_AND_MEAN to enhance the build process in Visual C++

To speed the build process, Visual C++ and the Windows Headers provide the following new defines: You can use them to reduce the size of the Win32 header files.

VC_EXTRALEAN and WIN32_LEAN_AND_MEAN are used to exclude rarely-used services from Windows headers. VC_EXTRALEAN can only be used in MFC projects, but WIN32_LEAN_AND_MEAN can be used in any project.

VC_EXTRALEAN defines the following in AFXV_W32.h: WIN32_EXTRA_LEAN does not do anything. Please refer to Windows.h for information concerning the NOxxx symbols that are being defined.

Newly-generated Visual C++ 5.0 and later AppWizard applications automatically benefit from VC_EXTRALEAN. You can also manually define VC_EXTRALEAN to speed the build process of many older MFC applications.

WIN32_LEAN_AND_MEAN: Windows Headers use this symbol to exclude rarely-used header files. Please refer to Windows.H to determine the files that will be excluded when this symbol is defined. Since MFC defines WIN32_LEAN_AND_MEAN, all MFC projects automatically use it.

Non-MFC C++ and C applications can define WIN32_LEAN_AND_MEAN and any applicable NOservice defines, such as NOSOUND (see DevStudio\Vc\include\Windows.h), to reduce their build times.

To add these defines, from the Project menu, choose Settings. The Projects settings dialog box appears. Click the C/C++ tab. In the Category list, select Preprocessor. Add the desired definitions to the Preprocessor Definitions box.