1ae3cff1eb
In #49289, rustc was changed to emit metadata for binaries, which made it so that the librustc.rmeta file created when compiling librustc was overwritten by the rustc-main compilation. This commit renames the rustc-main binary to avoid this problem. https://github.com/rust-lang/cargo/issues/5524 has also been filed to see if Cargo can learn to warn on this situation instead of leaving it for the user to debug.