rust/compiler/rustc_driver_impl
Nicholas Nethercote 781111ef35 Use Cow in {D,Subd}iagnosticMessage.
Each of `{D,Subd}iagnosticMessage::{Str,Eager}` has a comment:
```
// FIXME(davidtwco): can a `Cow<'static, str>` be used here?
```
This commit answers that question in the affirmative. It's not the most
compelling change ever, but it might be worth merging.

This requires changing the `impl<'a> From<&'a str>` impls to `impl
From<&'static str>`, which involves a bunch of knock-on changes that
require/result in call sites being a little more precise about exactly
what kind of string they use to create errors, and not just `&str`. This
will result in fewer unnecessary allocations, though this will not have
any notable perf effects given that these are error paths.

Note that I was lazy within Clippy, using `to_string` in a few places to
preserve the existing string imprecision. I could have used `impl
Into<{D,Subd}iagnosticMessage>` in various places as is done in the
compiler, but that would have required changes to *many* call sites
(mostly changing `&format("...")` to `format!("...")`) which didn't seem
worthwhile.
2023-05-29 09:23:43 +10:00
..
src Use Cow in {D,Subd}iagnosticMessage. 2023-05-29 09:23:43 +10:00
Cargo.toml bump windows crate 0.46 -> 0.48 in workspace 2023-05-09 18:20:13 +03:00
messages.ftl Ensure Fluent messages are in alphabetical order 2023-05-25 23:49:35 +00:00
README.md

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.