Bumping syntax-ap crates fails due to reduced visiblities

[josephlr]

I'm trying to fix rust-osdev/uefi-rs#104 (comment). Rustfmt needs a new engough syntax to support "efiapi". I tired to do what #3870 did and bump rustc-ap-syntax to version 626.

This caused a very large number of compiler errors. Some of them are caused by small changes like: rust-lang/rust@742ec4b, which are easy enough to fix. However, others errors are caused by changes like rust-lang/rust@c189565 that make a bunch of libsyntax's functionality private.

What should I do here? Should the libsyntax commits be reverted in the main rust-lang/rust repo?

CC: @Centril

[calebcartwright]

This looks like it may be tricky. Do you know the first/earliest version of rustc-ap that supports efiapi?

IIRC rustfmt 1.4.9 is using 606 and the latest on master has been bumped to 610, but the visibility changes in 626 appear very problematic

[topecongiro]

@josephlr Thank you for the report. I am aware of the visibility issue, and was planning to fix the issue once he refactoring thing has settled. We need to re-export everything we need in the libsyntax, adding comments to make sure they won't become private or removed in the future.

[topecongiro]

cc rust-lang/rust#65324.

[mati865]

@topecongiro IIUC this will block updating currently broken RLS.
If I'm correct this should be prioritised.

[est31]

@josephlr @mati865 if it helps you, the latest version that doesn't have rust-lang/rust@c189565 yet is 615, and the latest version that doesn't have rust-lang/rust@742ec4b either is 612.

efiapi was merged much later in rust-lang/rust@2dd4e73 (earliest rustc-ap-syntax version is 626)

[topecongiro]

@mati865 I do not think this is blocking the broken RLS as AFAIK RLS does not directly depend on rustc-ap-* crates.

[topecongiro]

For anyone interested in tackling this issue, here are the instructions:

1. Fork & clone this repo.
2. Edit Cargo.toml and bump the version of rustc-ap-* crates to the latest version.
3. Run cargo check. You will see TONS of compiler errors. Fix them if possible. For unfixable ones, we need to update the rustc source code.
4. Fork & clone https://github.com/rust-lang/rust.
5. Update libsyntax so that rustfmt can access structs/functions and methods that it depends on. Add a comment on each one of them so that they won't get hidden in future development (e.g., // Keep this public for external tools like rustfmt.).
6. Send a PR to the rustc repo.
7. Wait for the PR to get merged & wait for the rustc-ap-* crates to be published. Note that regularly rustc-ap-* crates are published once a week (https://crates.io/crates/rustc-ap-syntax).
8. Come back to the rustfmt repo, bump the version of rustc-ap-* crates and see if everything works. If not, go back to 5 😞

[topecongiro]

This is blocked by alexcrichton/rustc-auto-publish#14. cc @calebcartwright.