[INFO] fetching crate optimistic_lock_coupling 0.2.5...
[INFO] testing optimistic_lock_coupling-0.2.5 against 1.91.0 for beta-1.92-2
[INFO] extracting crate optimistic_lock_coupling 0.2.5 into /workspace/builds/worker-7-tc1/source
[INFO] started tweaking crates.io crate optimistic_lock_coupling 0.2.5
[INFO] finished tweaking crates.io crate optimistic_lock_coupling 0.2.5
[INFO] tweaked toml for crates.io crate optimistic_lock_coupling 0.2.5 written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate optimistic_lock_coupling 0.2.5 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] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.91.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 62 packages to latest compatible versions
[INFO] [stderr]       Adding criterion v0.3.6 (available: v0.7.0)
[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]  Downloading crates ...
[INFO] [stderr]   Downloaded criterion-plot v0.4.5
[INFO] [stderr]   Downloaded csv-core v0.1.13
[INFO] [stderr]   Downloaded criterion v0.3.6
[INFO] [stderr]   Downloaded csv v1.4.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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] 6e4ec709c61cf46866cd1de71c8acf7a7f502477848a4a23ccd94af992945e54
[INFO] running `Command { std: "docker" "start" "-a" "6e4ec709c61cf46866cd1de71c8acf7a7f502477848a4a23ccd94af992945e54", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6e4ec709c61cf46866cd1de71c8acf7a7f502477848a4a23ccd94af992945e54", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6e4ec709c61cf46866cd1de71c8acf7a7f502477848a4a23ccd94af992945e54", kill_on_drop: false }`
[INFO] [stdout] 6e4ec709c61cf46866cd1de71c8acf7a7f502477848a4a23ccd94af992945e54
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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] ca82f500832011967c966d7e7ea76fa78fccf3909e3f4f5725c55231cafb9c75
[INFO] running `Command { std: "docker" "start" "-a" "ca82f500832011967c966d7e7ea76fa78fccf3909e3f4f5725c55231cafb9c75", kill_on_drop: false }`
[INFO] [stderr]    Compiling optimistic_lock_coupling v0.2.5 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(negative_impls)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(unboxed_closures)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[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(stmt_expr_attributes)]
[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 `optimistic_lock_coupling` (lib) due to 3 previous errors
[INFO] running `Command { std: "docker" "inspect" "ca82f500832011967c966d7e7ea76fa78fccf3909e3f4f5725c55231cafb9c75", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ca82f500832011967c966d7e7ea76fa78fccf3909e3f4f5725c55231cafb9c75", kill_on_drop: false }`
[INFO] [stdout] ca82f500832011967c966d7e7ea76fa78fccf3909e3f4f5725c55231cafb9c75
