[INFO] fetching crate lark-string 0.1.0...
[INFO] checking lark-string-0.1.0 against master#0d37dca25a51fb900a402c94c8818ad1c2789e30 for pr-77526
[INFO] extracting crate lark-string 0.1.0 into /workspace/builds/worker-8/source
[INFO] validating manifest of crates.io crate lark-string 0.1.0 on toolchain 0d37dca25a51fb900a402c94c8818ad1c2789e30
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+0d37dca25a51fb900a402c94c8818ad1c2789e30" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate lark-string 0.1.0
[INFO] finished tweaking crates.io crate lark-string 0.1.0
[INFO] tweaked toml for crates.io crate lark-string 0.1.0 written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+0d37dca25a51fb900a402c94c8818ad1c2789e30" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+0d37dca25a51fb900a402c94c8818ad1c2789e30" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+0d37dca25a51fb900a402c94c8818ad1c2789e30" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] efbce0f02c51b8b47686d5bbecb566d2745d3dc411bb371e5d66a327d645b2bd
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "efbce0f02c51b8b47686d5bbecb566d2745d3dc411bb371e5d66a327d645b2bd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "efbce0f02c51b8b47686d5bbecb566d2745d3dc411bb371e5d66a327d645b2bd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "efbce0f02c51b8b47686d5bbecb566d2745d3dc411bb371e5d66a327d645b2bd", kill_on_drop: false }`
[INFO] [stdout] efbce0f02c51b8b47686d5bbecb566d2745d3dc411bb371e5d66a327d645b2bd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+0d37dca25a51fb900a402c94c8818ad1c2789e30" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 81dc4d757fee00ed42a8873a665be67bd0bc7b2fc43b9d6466e66d1f926ad628
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "81dc4d757fee00ed42a8873a665be67bd0bc7b2fc43b9d6466e66d1f926ad628", kill_on_drop: false }`
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]     Checking hashbrown v0.9.1
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr]    Compiling indexmap v1.6.0
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking smallvec v0.6.13
[INFO] [stderr]     Checking rand_chacha v0.1.1
[INFO] [stderr]     Checking rand_xorshift v0.1.1
[INFO] [stderr]     Checking rand_isaac v0.1.1
[INFO] [stderr]     Checking rand_hc v0.1.0
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]     Checking rand v0.6.5
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]    Compiling parking_lot_core v0.4.0
[INFO] [stderr]     Checking lark-debug-with v0.1.0
[INFO] [stderr]     Checking lark-collections v0.1.0
[INFO] [stderr]     Checking parking_lot v0.7.1
[INFO] [stderr]     Checking lark-intern v0.1.0
[INFO] [stderr]     Checking lark-string v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]  --> src/lib.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(specialization)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]  --> src/lib.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(specialization)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 10.75s
[INFO] running `Command { std: "docker" "inspect" "81dc4d757fee00ed42a8873a665be67bd0bc7b2fc43b9d6466e66d1f926ad628", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "81dc4d757fee00ed42a8873a665be67bd0bc7b2fc43b9d6466e66d1f926ad628", kill_on_drop: false }`
[INFO] [stdout] 81dc4d757fee00ed42a8873a665be67bd0bc7b2fc43b9d6466e66d1f926ad628