When rebuilding an package from an updated repository, is there a way to skip compilation on files that haven't changed?

I know this is a bit of a shot in the dark, but when I update a repository (c, c++, and so forth) and know that only a few files have changed, it's aggrivating to have to have everything recompile on larger projects. Is there a way to skip these? For example, is there a checksum that can be done against the built object and source that will be checked upon a rebuild?