Defining environment variables for visual studio 2010 to use during build?
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I am working on quite a large project that has to compile in Debug and Release for both 32 bit and 64 bit versions. It also has to be portable. The problem is, the linking dependencies (.lib) change since I have to link with either 32 bit or 64 bit libraries. To simplify matters, I have the following kind of setup for "additional library dependencies" for linker:
$(LIB_HOME)/core/bin;...

Where LIB_HOME points to the home of the correct version of the library. 

Now I currently set LIB_HOME in a batch file which then starts up visual studio 2010. With this method, unfortunately, I have to restart visual studio every time I want to switch from 32 or 64 bit. I saw the "environment" setting under the debugging options but those environment variables only seem to kick in at runtime. 

Is there any way, or any tool that I can use to set build-time environment variables for visual studio 2010 so that I can easily switch between debug and release in both 32 bit and 64 bit modes and the environment variables will be set correctly? How is this problem usually dealt with?

Thanks