[INFO] cloning repository https://github.com/steffenhaug/freelist
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/steffenhaug/freelist" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsteffenhaug%2Ffreelist", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsteffenhaug%2Ffreelist'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 2e6f8cdbf15480ec39f7c8a8c8e80c100136e42a
[INFO] checking steffenhaug/freelist against try#f47dd4da3ae8c32c9e65d307bfe640b143e674df for pr-77526
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsteffenhaug%2Ffreelist" "/workspace/builds/worker-9/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-9/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/steffenhaug/freelist on toolchain f47dd4da3ae8c32c9e65d307bfe640b143e674df
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/steffenhaug/freelist
[INFO] finished tweaking git repo https://github.com/steffenhaug/freelist
[INFO] tweaked toml for git repo https://github.com/steffenhaug/freelist written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] crate git repo https://github.com/steffenhaug/freelist already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded failure_derive v0.1.4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 300f7d10cdaaed7340d7f065305ca65be9586fe8dcc0d0dfbf5c07fc78027db2
[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" "300f7d10cdaaed7340d7f065305ca65be9586fe8dcc0d0dfbf5c07fc78027db2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "300f7d10cdaaed7340d7f065305ca65be9586fe8dcc0d0dfbf5c07fc78027db2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "300f7d10cdaaed7340d7f065305ca65be9586fe8dcc0d0dfbf5c07fc78027db2", kill_on_drop: false }`
[INFO] [stdout] 300f7d10cdaaed7340d7f065305ca65be9586fe8dcc0d0dfbf5c07fc78027db2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2cd08c7145a817191a99fc58cf5762ac4cd3ed9622d72d1678d6ee8ce3baedbf
[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" "2cd08c7145a817191a99fc58cf5762ac4cd3ed9622d72d1678d6ee8ce3baedbf", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.45
[INFO] [stderr]    Compiling version_check v0.1.5
[INFO] [stderr]    Compiling serde v1.0.83
[INFO] [stderr]    Compiling autocfg v0.1.1
[INFO] [stderr]    Compiling unicode-xid v0.0.4
[INFO] [stderr]    Compiling failure_derive v0.1.4
[INFO] [stderr]     Checking ucd-util v0.1.3
[INFO] [stderr]     Checking rustc-demangle v0.1.11
[INFO] [stderr]    Compiling quote v0.3.15
[INFO] [stderr]    Compiling regex v1.1.0
[INFO] [stderr]     Checking utf8-ranges v1.0.2
[INFO] [stderr]     Checking same-file v1.0.4
[INFO] [stderr]     Checking vec_map v0.8.1
[INFO] [stderr]     Checking byteorder v1.2.7
[INFO] [stderr]     Checking bitflags v1.0.4
[INFO] [stderr]     Checking ansi_term v0.11.0
[INFO] [stderr]     Checking allocators v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]    Compiling synom v0.11.3
[INFO] [stderr]     Checking walkdir v2.2.7
[INFO] [stdout] warning: unused imports: `RefMut`, `Ref`
[INFO] [stdout]  --> src/pile.rs:2:26
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::cell::{RefCell, Ref, RefMut};
[INFO] [stdout]   |                          ^^^  ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::fmt`
[INFO] [stdout]  --> src/pile.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::fmt;
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking regex-syntax v0.6.4
[INFO] [stderr]    Compiling proc-macro2 v0.4.24
[INFO] [stdout] warning: field is never read: `data`
[INFO] [stdout]   --> src/slotmap.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 |     data:       Vec<Entry<T>>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `slots`
[INFO] [stdout]   --> src/slotmap.rs:11:5
[INFO] [stdout]    |
[INFO] [stdout] 11 |     slots:      Vec<Slot>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `free_data`
[INFO] [stdout]   --> src/slotmap.rs:12:5
[INFO] [stdout]    |
[INFO] [stdout] 12 |     free_data:  Option<usize>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `free_slots`
[INFO] [stdout]   --> src/slotmap.rs:13:5
[INFO] [stdout]    |
[INFO] [stdout] 13 |     free_slots: Option<usize>
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/pile.rs:83:9
[INFO] [stdout]    |
[INFO] [stdout] 83 | /         mem::replace(
[INFO] [stdout] 84 | |             &mut self.memory[address],
[INFO] [stdout] 85 | |             Entry::Free {
[INFO] [stdout] 86 | |                 next: self.free_head,
[INFO] [stdout] 87 | |             },
[INFO] [stdout] 88 | |         );
[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: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]   --> src/main.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let t = fl.remove(x);
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `u`
[INFO] [stdout]   --> src/main.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let u = fl.insert(42);
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_u`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]   --> src/main.rs:18:9
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let v = fl.insert(69);
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling memchr v2.1.2
[INFO] [stderr]    Compiling lazy_static v1.1.0
[INFO] [stderr]    Compiling pest_derive v1.0.8
[INFO] [stderr]    Compiling backtrace v0.3.13
[INFO] [stderr]     Checking thread_local v0.3.6
[INFO] [stderr]    Compiling quote v0.6.10
[INFO] [stderr]    Compiling syn v0.15.23
[INFO] [stderr]     Checking backtrace-sys v0.1.28
[INFO] [stderr]     Checking rand v0.4.3
[INFO] [stderr]     Checking num_cpus v1.9.0
[INFO] [stderr]     Checking atty v0.2.11
[INFO] [stderr]     Checking clap v2.32.0
[INFO] [stderr]     Checking aho-corasick v0.6.9
[INFO] [stderr]     Checking csv-core v0.1.5
[INFO] [stderr]     Checking criterion-stats v0.3.0
[INFO] [stderr]    Compiling synstructure v0.10.1
[INFO] [stderr]    Compiling serde_derive v1.0.83
[INFO] [stderr]     Checking serde_json v1.0.33
[INFO] [stderr]     Checking csv v1.0.5
[INFO] [stderr]     Checking failure v0.1.4
[INFO] [stderr]     Checking criterion-plot v0.2.7
[INFO] [stderr]     Checking handlebars v1.0.5
[INFO] [stderr]     Checking criterion v0.2.7
[INFO] [stdout] warning: unused imports: `RefMut`, `Ref`
[INFO] [stdout]  --> src/pile.rs:2:26
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::cell::{RefCell, Ref, RefMut};
[INFO] [stdout]   |                          ^^^  ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::fmt`
[INFO] [stdout]  --> src/pile.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::fmt;
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `t`
[INFO] [stdout]   --> src/main.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 11 |     let t = fl.remove(x);
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_t`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `u`
[INFO] [stdout]   --> src/main.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let u = fl.insert(42);
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_u`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]   --> src/main.rs:18:9
[INFO] [stdout]    |
[INFO] [stdout] 18 |     let v = fl.insert(69);
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `#[macro_use]` import
[INFO] [stdout]  --> benches/alloc_bench.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #[macro_use]
[INFO] [stdout]   | ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `data`
[INFO] [stdout]   --> src/slotmap.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 |     data:       Vec<Entry<T>>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `slots`
[INFO] [stdout]   --> src/slotmap.rs:11:5
[INFO] [stdout]    |
[INFO] [stdout] 11 |     slots:      Vec<Slot>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `free_data`
[INFO] [stdout]   --> src/slotmap.rs:12:5
[INFO] [stdout]    |
[INFO] [stdout] 12 |     free_data:  Option<usize>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `free_slots`
[INFO] [stdout]   --> src/slotmap.rs:13:5
[INFO] [stdout]    |
[INFO] [stdout] 13 |     free_slots: Option<usize>
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/pile.rs:83:9
[INFO] [stdout]    |
[INFO] [stdout] 83 | /         mem::replace(
[INFO] [stdout] 84 | |             &mut self.memory[address],
[INFO] [stdout] 85 | |             Entry::Free {
[INFO] [stdout] 86 | |                 next: self.free_head,
[INFO] [stdout] 87 | |             },
[INFO] [stdout] 88 | |         );
[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: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 56.40s
[INFO] running `Command { std: "docker" "inspect" "2cd08c7145a817191a99fc58cf5762ac4cd3ed9622d72d1678d6ee8ce3baedbf", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2cd08c7145a817191a99fc58cf5762ac4cd3ed9622d72d1678d6ee8ce3baedbf", kill_on_drop: false }`
[INFO] [stdout] 2cd08c7145a817191a99fc58cf5762ac4cd3ed9622d72d1678d6ee8ce3baedbf