[INFO] fetching crate istring 0.2.1...
[INFO] checking istring-0.2.1 against master#d902752866cbbdb331e3cf28ff6bba86ab0f6c62 for pr-77271
[INFO] extracting crate istring 0.2.1 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate istring 0.2.1 on toolchain d902752866cbbdb331e3cf28ff6bba86ab0f6c62
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d902752866cbbdb331e3cf28ff6bba86ab0f6c62" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate istring 0.2.1
[INFO] finished tweaking crates.io crate istring 0.2.1
[INFO] tweaked toml for crates.io crate istring 0.2.1 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d902752866cbbdb331e3cf28ff6bba86ab0f6c62" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d902752866cbbdb331e3cf28ff6bba86ab0f6c62" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "+d902752866cbbdb331e3cf28ff6bba86ab0f6c62" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] cbe3b4063487bdd535be7dff02480fd496c4da778c6d5d3bcf189de9f22b6389
[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" "cbe3b4063487bdd535be7dff02480fd496c4da778c6d5d3bcf189de9f22b6389", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cbe3b4063487bdd535be7dff02480fd496c4da778c6d5d3bcf189de9f22b6389", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cbe3b4063487bdd535be7dff02480fd496c4da778c6d5d3bcf189de9f22b6389", kill_on_drop: false }`
[INFO] [stdout] cbe3b4063487bdd535be7dff02480fd496c4da778c6d5d3bcf189de9f22b6389
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "+d902752866cbbdb331e3cf28ff6bba86ab0f6c62" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 159b52d9465840086cd7c61c0acaa5ffcaedb8b5d8d5192a4d9f7b6654c28bff
[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" "159b52d9465840086cd7c61c0acaa5ffcaedb8b5d8d5192a4d9f7b6654c28bff", kill_on_drop: false }`
[INFO] [stderr]     Checking istring v0.2.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/lib.rs:136:46
[INFO] [stdout]     |
[INFO] [stdout] 136 |     pub fn with_capacity_in(capacity: usize, mut alloc: A) -> IString<A> {
[INFO] [stdout]     |                                              ----^^^^^
[INFO] [stdout]     |                                              |
[INFO] [stdout]     |                                              help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/lib.rs:136:46
[INFO] [stdout]     |
[INFO] [stdout] 136 |     pub fn with_capacity_in(capacity: usize, mut alloc: A) -> IString<A> {
[INFO] [stdout]     |                                              ----^^^^^
[INFO] [stdout]     |                                              |
[INFO] [stdout]     |                                              help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[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 0.47s
[INFO] running `Command { std: "docker" "inspect" "159b52d9465840086cd7c61c0acaa5ffcaedb8b5d8d5192a4d9f7b6654c28bff", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "159b52d9465840086cd7c61c0acaa5ffcaedb8b5d8d5192a4d9f7b6654c28bff", kill_on_drop: false }`
[INFO] [stdout] 159b52d9465840086cd7c61c0acaa5ffcaedb8b5d8d5192a4d9f7b6654c28bff