[INFO] fetching crate incremental-writer 0.1.2...
[INFO] testing incremental-writer-0.1.2 against 1.99.0-beta.8+cargoflags=--release for beta-release-1.100-2
[INFO] extracting crate incremental-writer 0.1.2 into /workspace/builds/worker-7-tc1/source
[INFO] started tweaking crates.io crate incremental-writer 0.1.2
[INFO] finished tweaking crates.io crate incremental-writer 0.1.2
[INFO] tweaked toml for crates.io crate incremental-writer 0.1.2 written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate incremental-writer 0.1.2 on toolchain 1.99.0-beta.8
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.99.0-beta.8" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate incremental-writer 0.1.2 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.99.0-beta.8" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded serde v1.0.115
[INFO] [stderr]   Downloaded proc-macro2 v1.0.19
[INFO] [stderr]   Downloaded serde_derive v1.0.115
[INFO] [stderr]   Downloaded serde_json v1.0.57
[INFO] [stderr]   Downloaded syn v1.0.38
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,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" "-m" "1610612736" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:77db811e55d90add9212f6832c23229e3de5f1c1f9905e8cb07319ea15df73ac" "sleep" "infinity", kill_on_drop: false }`
[INFO] [stdout] 3960ce888be34387f1aa6770f01973a21a4a4b8ab37f20b98bd0381eef6bf2b4
[INFO] running `Command { std: "docker" "start" "3960ce888be34387f1aa6770f01973a21a4a4b8ab37f20b98bd0381eef6bf2b4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3960ce888be34387f1aa6770f01973a21a4a4b8ab37f20b98bd0381eef6bf2b4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-w" "/opt/rustwide/workdir" "--user" "0:0" "3960ce888be34387f1aa6770f01973a21a4a4b8ab37f20b98bd0381eef6bf2b4" "/opt/rustwide/cargo-home/bin/cargo" "+1.99.0-beta.8" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3960ce888be34387f1aa6770f01973a21a4a4b8ab37f20b98bd0381eef6bf2b4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-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" "-w" "/opt/rustwide/workdir" "--user" "0:0" "3960ce888be34387f1aa6770f01973a21a4a4b8ab37f20b98bd0381eef6bf2b4" "/opt/rustwide/cargo-home/bin/cargo" "+1.99.0-beta.8" "build" "--frozen" "--message-format=json" "--release", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.19
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]    Compiling syn v1.0.38
[INFO] [stderr]    Compiling serde_derive v1.0.115
[INFO] [stderr]    Compiling serde v1.0.115
[INFO] [stderr]    Compiling serde_json v1.0.57
[INFO] [stderr]    Compiling itoa v0.4.6
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]    Compiling incremental-writer v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: struct `Record` is never constructed
[INFO] [stdout]    --> src/json/mod.rs:104:8
[INFO] [stdout]     |
[INFO] [stdout] 104 | struct Record { 
[INFO] [stdout]     |        ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `release` profile [optimized] target(s) in 11.69s
[INFO] running `Command { std: "docker" "inspect" "3960ce888be34387f1aa6770f01973a21a4a4b8ab37f20b98bd0381eef6bf2b4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-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" "-w" "/opt/rustwide/workdir" "--user" "0:0" "3960ce888be34387f1aa6770f01973a21a4a4b8ab37f20b98bd0381eef6bf2b4" "/opt/rustwide/cargo-home/bin/cargo" "+1.99.0-beta.8" "test" "--frozen" "--no-run" "--message-format=json" "--release", kill_on_drop: false }`
[INFO] [stderr]    Compiling incremental-writer v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: struct `Record` is never constructed
[INFO] [stdout]    --> src/json/mod.rs:104:8
[INFO] [stdout]     |
[INFO] [stdout] 104 | struct Record { 
[INFO] [stdout]     |        ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `release` profile [optimized] target(s) in 1.07s
[INFO] running `Command { std: "docker" "inspect" "3960ce888be34387f1aa6770f01973a21a4a4b8ab37f20b98bd0381eef6bf2b4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-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" "-w" "/opt/rustwide/workdir" "--user" "0:0" "3960ce888be34387f1aa6770f01973a21a4a4b8ab37f20b98bd0381eef6bf2b4" "/opt/rustwide/cargo-home/bin/cargo" "+1.99.0-beta.8" "test" "--frozen" "--release", kill_on_drop: false }`
[INFO] [stderr] warning: struct `Record` is never constructed
[INFO] [stderr]    --> src/json/mod.rs:104:8
[INFO] [stderr]     |
[INFO] [stderr] 104 | struct Record { 
[INFO] [stderr]     |        ^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `incremental-writer` (lib) generated 1 warning
[INFO] [stderr]     Finished `release` profile [optimized] target(s) in 0.03s
[INFO] [stderr]      Running unittests src/lib.rs (/opt/rustwide/target/release/deps/incremental_writer-05ba78a27440b42d)
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stdout] test json::writer_writes_square_brackets_to_buffer ... FAILED
[INFO] [stderr] error: test failed, to rerun pass `--lib`
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout] 
[INFO] [stdout] ---- json::writer_writes_square_brackets_to_buffer stdout ----
[INFO] [stdout] 
[INFO] [stdout] thread 'json::writer_writes_square_brackets_to_buffer' (477) panicked at src/json/mod.rs:81:46:
[INFO] [stdout] called `Result::unwrap()` on an `Err` value: Os { code: 30, kind: ReadOnlyFilesystem, message: "Read-only file system" }
[INFO] [stdout] stack backtrace:
[INFO] [stdout]    0:     0x61afbed16a51 - <<std[70759c8f55707aa4]::sys::backtrace::BacktraceLock>::print::DisplayBacktrace as core[df12db4294e9bfd3]::fmt::Display>::fmt
[INFO] [stdout]    1:     0x61afbed2acca - core[df12db4294e9bfd3]::fmt::write
[INFO] [stdout]    2:     0x61afbed1af8c - <alloc[2182bb758b4b3781]::vec::Vec<u8> as core[df12db4294e9bfd3]::io::write::Write>::write_fmt
[INFO] [stdout]    3:     0x61afbecf2fd6 - std[70759c8f55707aa4]::panicking::default_hook::{closure#0}
[INFO] [stdout]    4:     0x61afbed0f149 - std[70759c8f55707aa4]::panicking::default_hook
[INFO] [stdout]    5:     0x61afbecab5d0 - test[9d35eded1c95d3be]::test_main_inner::<test[9d35eded1c95d3be]::test_main_static::{closure#0}>::{closure#0}
[INFO] [stdout]    6:     0x61afbed0f302 - std[70759c8f55707aa4]::panicking::panic_with_hook
[INFO] [stdout]    7:     0x61afbecf3082 - std[70759c8f55707aa4]::panicking::panic_handler::{closure#0}
[INFO] [stdout]    8:     0x61afbecebe09 - std[70759c8f55707aa4]::sys::backtrace::__rust_end_short_backtrace::<std[70759c8f55707aa4]::panicking::panic_handler::{closure#0}, !>
[INFO] [stdout]    9:     0x61afbecf3c7d - __rustc[8fa7c3cbc660c2b3]::rust_begin_unwind
[INFO] [stdout]   10:     0x61afbed2b3fc - core[df12db4294e9bfd3]::panicking::panic_fmt
[INFO] [stdout]   11:     0x61afbed2b1d2 - core[df12db4294e9bfd3]::result::unwrap_failed
[INFO] [stdout]   12:     0x61afbec9d9f9 - <incremental_writer[e7c82ef5012cea0b]::json::writer_writes_square_brackets_to_buffer::{closure#0} as core[df12db4294e9bfd3]::ops::function::FnOnce<()>>::call_once
[INFO] [stdout]   13:     0x61afbec9e8bb - test[9d35eded1c95d3be]::__rust_begin_short_backtrace::<core[df12db4294e9bfd3]::result::Result<(), alloc[2182bb758b4b3781]::string::String>, fn() -> core[df12db4294e9bfd3]::result::Result<(), alloc[2182bb758b4b3781]::string::String>>
[INFO] [stdout]   14:     0x61afbecabf25 - test[9d35eded1c95d3be]::run_test::{closure#0}
[INFO] [stdout]   15:     0x61afbeca57e4 - std[70759c8f55707aa4]::sys::backtrace::__rust_begin_short_backtrace::<test[9d35eded1c95d3be]::run_test::{closure#1}, ()>
[INFO] [stdout]   16:     0x61afbecaf082 - <std[70759c8f55707aa4]::thread::lifecycle::spawn_unchecked<test[9d35eded1c95d3be]::run_test::{closure#1}, ()>::{closure#1} as core[df12db4294e9bfd3]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
[INFO] [stdout]   17:     0x61afbed162b9 - <std[70759c8f55707aa4]::sys::thread::unix::Thread>::new::thread_start
[INFO] [stdout]   18:     0x785b6de67dfa - <unknown>
[INFO] [stdout]   19:     0x785b6defb3d4 - clone
[INFO] [stdout]   20:                0x0 - <unknown>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout]     json::writer_writes_square_brackets_to_buffer
[INFO] [stdout] 
[INFO] [stdout] test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "3960ce888be34387f1aa6770f01973a21a4a4b8ab37f20b98bd0381eef6bf2b4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3960ce888be34387f1aa6770f01973a21a4a4b8ab37f20b98bd0381eef6bf2b4", kill_on_drop: false }`
[INFO] [stdout] 3960ce888be34387f1aa6770f01973a21a4a4b8ab37f20b98bd0381eef6bf2b4
