Build script does not respect RUSTC_WRAPPER #3772
Description
This came up in rust-lang/rust#127682: the build scripts invokes RUSTC without wrapping it in RUSTC_WRAPPER. Bypassing wrappers isn't great, so the build script should be fixed. See cuviper/autocfg#56, djc/rustc-version-rs#46 for similar changes in other crates, and rust-lang/cargo#13659 for the change in cargo.