Only depend on CFG_VERSION in rustc_interface This avoids having to rebuild the whole compiler on each commit when `omit-git-hash = false`. cc https://github.com/rust-lang/rust/issues/76720 - this won't fix it, and I'm not suggesting we turn this on by default, but it will make it less painful for people who do have `omit-git-hash` on as a workaround.