[INFO] fetching crate sav 0.2.0...
[INFO] testing sav-0.2.0 against 1.91.0 for beta-1.92-2
[INFO] extracting crate sav 0.2.0 into /workspace/builds/worker-5-tc1/source
[INFO] started tweaking crates.io crate sav 0.2.0
[INFO] finished tweaking crates.io crate sav 0.2.0
[INFO] tweaked toml for crates.io crate sav 0.2.0 written to /workspace/builds/worker-5-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate sav 0.2.0 on toolchain 1.91.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.91.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate sav 0.2.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.91.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded serde_cbor v0.11.2
[INFO] [stderr]   Downloaded winapi-util v0.1.9
[INFO] [stderr]   Downloaded atty v0.2.14
[INFO] [stderr]   Downloaded hermit-abi v0.1.19
[INFO] [stderr]   Downloaded plotters-svg v0.3.7
[INFO] [stderr]   Downloaded plotters-backend v0.3.7
[INFO] [stderr]   Downloaded criterion-plot v0.4.5
[INFO] [stderr]   Downloaded cast v0.3.0
[INFO] [stderr]   Downloaded wasm-bindgen-backend v0.2.100
[INFO] [stderr]   Downloaded csv-core v0.1.12
[INFO] [stderr]   Downloaded log v0.4.27
[INFO] [stderr]   Downloaded wasm-bindgen v0.2.100
[INFO] [stderr]   Downloaded half v1.8.3
[INFO] [stderr]   Downloaded serde_json v1.0.142
[INFO] [stderr]   Downloaded itertools v0.10.5
[INFO] [stderr]   Downloaded rayon-core v1.12.1
[INFO] [stderr]   Downloaded plotters v0.3.7
[INFO] [stderr]   Downloaded clap v2.34.0
[INFO] [stderr]   Downloaded rayon v1.10.0
[INFO] [stderr]   Downloaded proc-macro2 v1.0.95
[INFO] [stderr]   Downloaded regex v1.11.1
[INFO] [stderr]   Downloaded unicode-width v0.1.14
[INFO] [stderr]   Downloaded syn v2.0.104
[INFO] [stderr]   Downloaded unicode-ident v1.0.18
[INFO] [stderr]   Downloaded js-sys v0.3.77
[INFO] [stderr]   Downloaded wasm-bindgen-macro-support v0.2.100
[INFO] [stderr]   Downloaded criterion v0.3.6
[INFO] [stderr]   Downloaded regex-syntax v0.8.5
[INFO] [stderr]   Downloaded oorandom v11.1.5
[INFO] [stderr]   Downloaded wasm-bindgen-macro v0.2.100
[INFO] [stderr]   Downloaded tinytemplate v1.2.1
[INFO] [stderr]   Downloaded cfg-if v1.0.1
[INFO] [stderr]   Downloaded rustversion v1.0.21
[INFO] [stderr]   Downloaded wasm-bindgen-shared v0.2.100
[INFO] [stderr]   Downloaded crossbeam-deque v0.8.6
[INFO] [stderr]   Downloaded web-sys v0.3.77
[INFO] [stderr]   Downloaded regex-automata v0.4.9
[INFO] [stderr]   Downloaded libc v0.2.174
[INFO] [stderr]   Downloaded csv v1.3.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+1.91.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 28af30cc47e06bfe96965f3e6c5b5fa2674431755d29acb8749440ddde35b97f
[INFO] running `Command { std: "docker" "start" "-a" "28af30cc47e06bfe96965f3e6c5b5fa2674431755d29acb8749440ddde35b97f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "28af30cc47e06bfe96965f3e6c5b5fa2674431755d29acb8749440ddde35b97f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "28af30cc47e06bfe96965f3e6c5b5fa2674431755d29acb8749440ddde35b97f", kill_on_drop: false }`
[INFO] [stdout] 28af30cc47e06bfe96965f3e6c5b5fa2674431755d29acb8749440ddde35b97f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/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=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+1.91.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7d6d3ec799b79256c0f7ef16195e8a878c418df86f7e29570a1b586d878af42a
[INFO] running `Command { std: "docker" "start" "-a" "7d6d3ec799b79256c0f7ef16195e8a878c418df86f7e29570a1b586d878af42a", kill_on_drop: false }`
[INFO] [stderr]    Compiling sav v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(macro_metavar_expr)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `sav` (lib) due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "7d6d3ec799b79256c0f7ef16195e8a878c418df86f7e29570a1b586d878af42a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7d6d3ec799b79256c0f7ef16195e8a878c418df86f7e29570a1b586d878af42a", kill_on_drop: false }`
[INFO] [stdout] 7d6d3ec799b79256c0f7ef16195e8a878c418df86f7e29570a1b586d878af42a