run setup script before M-x compile

[Brendan Miller]

For a project I'm working on, I have to run a somewhat slow 
environmental setup script before running the makefile.

I'd like to take advantage of compilation mode. Is there some way to get 
M-x compile, or the like, to reuse an inferior shell that I've already 
executed my setup script in?

To be clear, the setup script changes the shell's environment, so it 
won't work to run the script in a separate shell.

Thanks