Don't enable anyhow's backtrace feature in opt-dist

[Zalathar]

As of the stabilization of std::backtrace in Rust 1.65, this package flag has no effect other than to enable an unused dependency on the backtrace crate.

(See https://github.com/dtolnay/anyhow/blob/af0937ef72fbaf9784a6c991e029738728d025e2/Cargo.toml#L18-L23.)

While the presence of this feature in opt-dist doesn't cause other tools (which use anyhow) to actually build backtrace, it does affect the global crate graph used for dependency version resolution. After removing this feature, we can use cargo tree --invert --package backtrace to see that the only remaining reverse-dependency of backtrace is color-eyre, which is used by ui_test.

[rustbot]

r? @Mark-Simulacrum

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[rustbot]

Some changes occurred in src/tools/opt-dist

cc @Kobzol

These commits modify the Cargo.lock file. Unintentional changes to Cargo.lock can be introduced when switching branches and rebasing PRs.

If this was unintentional then you should revert the changes before this PR is merged.
Otherwise, you can ignore this comment.

[Zalathar]

I noticed this while looking into why we use 3 different versions of gimli, via #135115 (comment).

[Zalathar]

(I'm not familiar with opt-dist, so it's possible that this is important for some reason that I'm not aware of, but I doubt it.)

[lqd]

How does an opt-dist error look with this PR?

[Zalathar]

As far as I can tell, the stack traces printed by opt-dist look identical with and without this PR, right down to the first line of the backtrace being this in both cases:

   0: std::backtrace_rs::backtrace::libunwind::trace

Here's the full stderr of an erroneous invocation of opt-dist. It's identical (other than timestamps) to the same invocation without this PR.

[2025-01-06T07:03:16.926Z INFO  opt_dist::utils::io] Resetting directory opt-artifacts
[2025-01-06T07:03:17.403Z INFO  opt_dist::utils::io] Copying directory ./src/tools/rustc-perf to opt-artifacts/rustc-perf
[2025-01-06T07:03:18.722Z INFO  opt_dist::exec] Executing `RUSTC=./build/bogus/stage0/bin/rustc RUSTC_BOOTSTRAP=1 ./build/bogus/stage0/bin/cargo build -p collector [at opt-artifacts/rustc-perf]`
[2025-01-06T07:03:18.723Z INFO  opt_dist] Timer results
    -----------------------------------------
    
    Total duration:                        0s
    -----------------------------------------
    
[2025-01-06T07:03:18.752Z INFO  opt_dist::utils] Free disk space: 994.42 GiB out of total 1.81 TiB (46.33% used)
Error: Optimized build pipeline has failed

Caused by:
    No such file or directory (os error 2)

Stack backtrace:
   0: std::backtrace_rs::backtrace::libunwind::trace
             at /rustc/b4297a573b4eefacd62e7ea1ba071536282d3254/library/std/src/../../backtrace/src/backtrace/libunwind.rs:116:5
   1: std::backtrace_rs::backtrace::trace_unsynchronized
             at /rustc/b4297a573b4eefacd62e7ea1ba071536282d3254/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2: std::backtrace::Backtrace::create
             at /rustc/b4297a573b4eefacd62e7ea1ba071536282d3254/library/std/src/backtrace.rs:331:13
   3: from<std::io::error::Error>
             at /Users/stuart/.cargo/registry/src/index.crates.io-6f17d22bba15001f/anyhow-1.0.95/src/backtrace.rs:27:14
   4: from_residual<(), std::io::error::Error, anyhow::Error>
             at /rustc/b4297a573b4eefacd62e7ea1ba071536282d3254/library/core/src/result.rs:2009:27
   5: run
             at ./src/tools/opt-dist/src/exec.rs:78:27
   6: build_rustc_perf
             at ./src/tools/opt-dist/src/main.rs:422:5
   7: copy_rustc_perf
             at ./src/tools/opt-dist/src/main.rs:418:5
   8: {closure#0}
             at ./src/tools/opt-dist/src/main.rs:205:9
   9: execute_pipeline
             at ./src/tools/opt-dist/src/main.rs:200:5
  10: main
             at ./src/tools/opt-dist/src/main.rs:401:18
  11: call_once<fn() -> core::result::Result<(), anyhow::Error>, ()>
             at /rustc/b4297a573b4eefacd62e7ea1ba071536282d3254/library/core/src/ops/function.rs:250:5
  12: __rust_begin_short_backtrace<fn() -> core::result::Result<(), anyhow::Error>, core::result::Result<(), anyhow::Error>>
             at /rustc/b4297a573b4eefacd62e7ea1ba071536282d3254/library/std/src/sys/backtrace.rs:154:18
  13: std::rt::lang_start::<core::result::Result<(), anyhow::Error>>::{closure#0}
  14: core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once
             at /rustc/b4297a573b4eefacd62e7ea1ba071536282d3254/library/core/src/ops/function.rs:284:13
  15: std::panicking::try::do_call
             at /rustc/b4297a573b4eefacd62e7ea1ba071536282d3254/library/std/src/panicking.rs:557:40
  16: std::panicking::try
             at /rustc/b4297a573b4eefacd62e7ea1ba071536282d3254/library/std/src/panicking.rs:520:19
  17: std::panic::catch_unwind
             at /rustc/b4297a573b4eefacd62e7ea1ba071536282d3254/library/std/src/panic.rs:358:14
  18: std::rt::lang_start_internal::{{closure}}
             at /rustc/b4297a573b4eefacd62e7ea1ba071536282d3254/library/std/src/rt.rs:174:48
  19: std::panicking::try::do_call
             at /rustc/b4297a573b4eefacd62e7ea1ba071536282d3254/library/std/src/panicking.rs:557:40
  20: std::panicking::try
             at /rustc/b4297a573b4eefacd62e7ea1ba071536282d3254/library/std/src/panicking.rs:520:19
  21: std::panic::catch_unwind
             at /rustc/b4297a573b4eefacd62e7ea1ba071536282d3254/library/std/src/panic.rs:358:14
  22: std::rt::lang_start_internal
             at /rustc/b4297a573b4eefacd62e7ea1ba071536282d3254/library/std/src/rt.rs:174:20
  23: _main

[jieyouxu]

Thanks

[jieyouxu]

r? jieyouxu @bors r+ rollup

[bors]

📌 Commit 85e0d42 has been approved by jieyouxu

It is now in the queue for this repository.