Function cargo::ops::fix_maybe_exec_rustc

pub fn fix_maybe_exec_rustc(config: &Config) -> CargoResult<bool>

Entry point for cargo running as a proxy for rustc.

This is called every time cargo is run to check if it is in proxy mode.

Returns false if fix is not being run (not in proxy mode). Returns true if in fix proxy mode, and the fix was complete without any warnings or errors. If there are warnings or errors, this does not return, and the process exits with the corresponding rustc exit code.