[INFO] fetching crate alloc-no-stdlib 2.0.1...
[INFO] documenting alloc-no-stdlib-2.0.1 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate alloc-no-stdlib 2.0.1 into /workspace/builds/worker-12/source
[INFO] validating manifest of crates.io crate alloc-no-stdlib 2.0.1 on toolchain beta-2020-08-29
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate alloc-no-stdlib 2.0.1
[INFO] finished tweaking crates.io crate alloc-no-stdlib 2.0.1
[INFO] tweaked toml for crates.io crate alloc-no-stdlib 2.0.1 written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "+beta-2020-08-29" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] fb7d192319d0581540c94d0db7dd703c434c705cd2ef94c2bf964675a41fb683
[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" "fb7d192319d0581540c94d0db7dd703c434c705cd2ef94c2bf964675a41fb683", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "fb7d192319d0581540c94d0db7dd703c434c705cd2ef94c2bf964675a41fb683", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fb7d192319d0581540c94d0db7dd703c434c705cd2ef94c2bf964675a41fb683", kill_on_drop: false }`
[INFO] [stdout] fb7d192319d0581540c94d0db7dd703c434c705cd2ef94c2bf964675a41fb683
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-08-29" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 647ed2aae7272976b0151f39ea62f5fdeb727ec09497e585b25f5090863b85cc
[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" "647ed2aae7272976b0151f39ea62f5fdeb727ec09497e585b25f5090863b85cc", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking alloc-no-stdlib v2.0.1 (/opt/rustwide/workdir)
[INFO] [stderr]  Documenting alloc-no-stdlib v2.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `core::mem::replace` that must be used
[INFO] [stdout]   --> src/stack_allocator.rs:66:17
[INFO] [stdout]    |
[INFO] [stdout] 66 | /                 core::mem::replace(&mut self.system_resources.slice_mut()[index],
[INFO] [stdout] 67 | |                                    farthest_free_list);
[INFO] [stdout]    | |_______________________________________________________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `core::mem::replace` that must be used
[INFO] [stdout]   --> src/stack_allocator.rs:74:13
[INFO] [stdout]    |
[INFO] [stdout] 74 |             core::mem::replace(&mut self.system_resources.slice_mut()[index], return_to_sender);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `core::mem::replace` that must be used
[INFO] [stdout]   --> src/stack_allocator.rs:85:13
[INFO] [stdout]    |
[INFO] [stdout] 85 | /             core::mem::replace(&mut self.system_resources.slice_mut()[self.free_list_start],
[INFO] [stdout] 86 | |                                val.mem);
[INFO] [stdout]    | |________________________________________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `core::mem::replace` that must be used
[INFO] [stdout]   --> src/stack_allocator.rs:93:20
[INFO] [stdout]    |
[INFO] [stdout] 93 | /                    core::mem::replace(&mut self.system_resources.slice_mut()[self.free_list_overflow_count],
[INFO] [stdout] 94 | |                                       val.mem);
[INFO] [stdout]    | |_______________________________________________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.40s
[INFO] running `Command { std: "docker" "inspect" "647ed2aae7272976b0151f39ea62f5fdeb727ec09497e585b25f5090863b85cc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "647ed2aae7272976b0151f39ea62f5fdeb727ec09497e585b25f5090863b85cc", kill_on_drop: false }`
[INFO] [stdout] 647ed2aae7272976b0151f39ea62f5fdeb727ec09497e585b25f5090863b85cc