784316eadc
Remove many `#[macro_use] extern crate foo` items This requires the addition of more `use` items, which often make the code more verbose. But they also make the code easier to read, because `#[macro_use]` obscures where macros are defined. r? `@fee1-dead`
The driver crate is effectively the "main" function for the rust
compiler. It orchestrates the compilation process and "knits together"
the code from the other crates within rustc. This crate itself does
not contain any of the "main logic" of the compiler (though it does
have some code related to pretty printing or other minor compiler
options).
For more information about how the driver works, see the rustc dev guide.