[INFO] fetching crate fifo 0.2.0...
[INFO] testing fifo-0.2.0 against try#dec9417b8611e34e787a3e4c37686b5131f9e5c5 for pr-154210-1
[INFO] extracting crate fifo 0.2.0 into /workspace/builds/worker-6-tc2/source
[INFO] started tweaking crates.io crate fifo 0.2.0
[INFO] finished tweaking crates.io crate fifo 0.2.0
[INFO] tweaked toml for crates.io crate fifo 0.2.0 written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate fifo 0.2.0 on toolchain dec9417b8611e34e787a3e4c37686b5131f9e5c5
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+dec9417b8611e34e787a3e4c37686b5131f9e5c5" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+dec9417b8611e34e787a3e4c37686b5131f9e5c5" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+dec9417b8611e34e787a3e4c37686b5131f9e5c5" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: `package.edition` is unspecified, defaulting to `2015` while the latest is `2024`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+dec9417b8611e34e787a3e4c37686b5131f9e5c5" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e42e3948d9ff4f083a529ca1bd40deb0b4bcb943469d7c42a12b042b89e2617e
[INFO] running `Command { std: "docker" "start" "-a" "e42e3948d9ff4f083a529ca1bd40deb0b4bcb943469d7c42a12b042b89e2617e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e42e3948d9ff4f083a529ca1bd40deb0b4bcb943469d7c42a12b042b89e2617e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e42e3948d9ff4f083a529ca1bd40deb0b4bcb943469d7c42a12b042b89e2617e", kill_on_drop: false }`
[INFO] [stdout] e42e3948d9ff4f083a529ca1bd40deb0b4bcb943469d7c42a12b042b89e2617e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+dec9417b8611e34e787a3e4c37686b5131f9e5c5" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d55afc24b953bb7ddfcb318d20fffce874139c56e26876c3cde04d7651b33a48
[INFO] running `Command { std: "docker" "start" "-a" "d55afc24b953bb7ddfcb318d20fffce874139c56e26876c3cde04d7651b33a48", kill_on_drop: false }`
[INFO] [stderr] warning: `package.edition` is unspecified, defaulting to `2015` while the latest is `2024`
[INFO] [stderr]    Compiling fifo v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]   --> src/lib.rs:22:12
[INFO] [stdout]    |
[INFO] [stdout] 22 | #![feature(optin_builtin_traits)]
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^^^^^^ feature has been removed
[INFO] [stdout]    |
[INFO] [stdout]    = note: removed in 1.50.0; see <https://github.com/rust-lang/rust/pull/79336> for more information
[INFO] [stdout]    = note: renamed to `auto_traits`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0432]: unresolved import `alloc::heap`
[INFO] [stdout]   --> src/lib.rs:30:5
[INFO] [stdout]    |
[INFO] [stdout] 30 | use alloc::heap;
[INFO] [stdout]    |     ^^^^^^^^^^^ no `heap` in the root
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not fully implemented; use marker types for now
[INFO] [stdout]    --> src/lib.rs:118:6
[INFO] [stdout]     |
[INFO] [stdout] 118 | impl !Sync for Sender {}
[INFO] [stdout]     |      ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this compiler was built on 2026-03-22; consider upgrading it if it is out of date
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not fully implemented; use marker types for now
[INFO] [stdout]    --> src/lib.rs:119:6
[INFO] [stdout]     |
[INFO] [stdout] 119 | impl !Sync for Receiver {}
[INFO] [stdout]     |      ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this compiler was built on 2026-03-22; consider upgrading it if it is out of date
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `alloc` has been stable since 1.36.0 and no longer requires an attribute to enable
[INFO] [stdout]   --> src/lib.rs:21:12
[INFO] [stdout]    |
[INFO] [stdout] 21 | #![feature(alloc, heap_api)]
[INFO] [stdout]    |            ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0635]: unknown feature `heap_api`
[INFO] [stdout]   --> src/lib.rs:21:19
[INFO] [stdout]    |
[INFO] [stdout] 21 | #![feature(alloc, heap_api)]
[INFO] [stdout]    |                   ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0432, E0557, E0635, E0658.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0432`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `fifo` (lib) due to 5 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "d55afc24b953bb7ddfcb318d20fffce874139c56e26876c3cde04d7651b33a48", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d55afc24b953bb7ddfcb318d20fffce874139c56e26876c3cde04d7651b33a48", kill_on_drop: false }`
[INFO] [stdout] d55afc24b953bb7ddfcb318d20fffce874139c56e26876c3cde04d7651b33a48