Auto merge of #143613 - Enselic:panic-abort-uwtables, r=petrochenkov

Fix backtraces with `-C panic=abort` on linux; emit unwind tables by default

The linux backtrace unwinder relies on unwind tables to work properly, and generating and printing a backtrace is done by for example the default panic hook.

Begin emitting unwind tables by default again with `-C panic=abort` (see history below) so that backtraces work.

Closes https://github.com/rust-lang/rust/issues/81902 which is **regression-from-stable-to-stable**
Closes https://github.com/rust-lang/rust/issues/94815

### History

Backtraces with `-C panic=abort` used to work in Rust 1.22 but broke in Rust 1.23, because in 1.23 we stopped emitting unwind tables with `-C panic=abort` (see https://github.com/rust-lang/rust/pull/45031 and https://github.com/rust-lang/rust/issues/81902#issuecomment-3046487084).

In 1.45 a workaround in the form of `-C force-unwind-tables=yes` was added (see https://github.com/rust-lang/rust/pull/69984).

`-C panic=abort` was added in [Rust 1.10](https://blog.rust-lang.org/2016/07/07/Rust-1.10/#what-s-in-1-10-stable) and the motivation was binary size and compile time. But given how confusing that behavior has turned out to be, it is better to make binary size optimization opt-in with `-C force-unwind-tables=no` rather than default since the current default breaks backtraces.

Besides, if binary size is a primary concern, there are many other tricks that can be used that has a higher impact.

# Release Note Entry Draft:

## Compatibility Notes

* [Fix backtraces with `-C panic=abort` on Linux by generating unwind tables by default](https://github.com/rust-lang/rust/pull/143613). Build with `-C force-unwind-tables=no` to keep omitting unwind tables.

try-job: aarch64-apple
try-job: armhf-gnu
try-job: aarch64-msvc-1
tree: bde490f179aab112761586dcc4f5c0b0d7d2ce75
  1. .cargo/
  2. .github/
  3. .vscode/
  4. assets/
  5. bench_data/
  6. crates/
  7. docs/
  8. editors/
  9. lib/
  10. xtask/
  11. .editorconfig
  12. .git-blame-ignore-revs
  13. .gitattributes
  14. .gitignore
  15. .typos.toml
  16. Cargo.lock
  17. Cargo.toml
  18. clippy.toml
  19. CONTRIBUTING.md
  20. josh-sync.toml
  21. LICENSE-APACHE
  22. LICENSE-MIT
  23. PRIVACY.md
  24. README.md
  25. rust-version
  26. rustfmt.toml
  27. triagebot.toml
README.md

rust-analyzer is a language server that provides IDE functionality for writing Rust programs. You can use it with any editor that supports the Language Server Protocol (VS Code, Vim, Emacs, Zed, etc).

rust-analyzer features include go-to-definition, find-all-references, refactorings and code completion. rust-analyzer also supports integrated formatting (with rustfmt) and integrated diagnostics (with rustc and clippy).

Internally, rust-analyzer is structured as a set of libraries for analyzing Rust code. See Architecture in the manual.

Quick Start

https://rust-analyzer.github.io/book/installation.html

Documentation

If you want to contribute to rust-analyzer check out the CONTRIBUTING.md or if you are just curious about how things work under the hood, see the Contributing section of the manual.

If you want to use rust-analyzer's language server with your editor of choice, check the manual. It also contains some tips & tricks to help you be more productive when using rust-analyzer.

Security and Privacy

See the security and privacy sections of the manual.

Communication

For usage and troubleshooting requests, please use “IDEs and Editors” category of the Rust forum:

https://users.rust-lang.org/c/ide/14

For questions about development and implementation, join rust-analyzer working group on Zulip:

https://rust-lang.zulipchat.com/#narrow/stream/185405-t-compiler.2Frust-analyzer

Quick Links

License

rust-analyzer is primarily distributed under the terms of both the MIT license and the Apache License (Version 2.0).

See LICENSE-APACHE and LICENSE-MIT for details.