there's nothing stopping someone from maintaining an egg file for something
they don't intend to package, and just building it with chicken-install
-no-install. could also use a custom build script to set the egg env vars too.
personally I just manage this stuff with my own build system tho,
set C_COMPILER in config.make and rebuild. I use this to do dev builds with
clang and just checked that it does make chicken-install use the same compiler
if you've already tried this and it didn't work, run `make spotless` and
`chicken-install -purge` and try again. the eggname.build.sh
