[INFO] cloning repository https://github.com/alexclear/rust-koans-answers
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/alexclear/rust-koans-answers" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Falexclear%2Frust-koans-answers", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Falexclear%2Frust-koans-answers'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 89e124c056c315e10c6d5ab8548902c0cfc64be5
[INFO] testing alexclear/rust-koans-answers against beta-2021-08-01 for beta-1.55-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Falexclear%2Frust-koans-answers" "/workspace/builds/worker-54/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-54/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/alexclear/rust-koans-answers on toolchain beta-2021-08-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/alexclear/rust-koans-answers
[INFO] finished tweaking git repo https://github.com/alexclear/rust-koans-answers
[INFO] tweaked toml for git repo https://github.com/alexclear/rust-koans-answers written to /workspace/builds/worker-54/source/Cargo.toml
[INFO] crate git repo https://github.com/alexclear/rust-koans-answers already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-54/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-54/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d5ec287184c7243f01520795eb005dfd1c68071130d4f920c297216439dbc8e8
[INFO] running `Command { std: "docker" "start" "-a" "d5ec287184c7243f01520795eb005dfd1c68071130d4f920c297216439dbc8e8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d5ec287184c7243f01520795eb005dfd1c68071130d4f920c297216439dbc8e8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d5ec287184c7243f01520795eb005dfd1c68071130d4f920c297216439dbc8e8", kill_on_drop: false }`
[INFO] [stdout] d5ec287184c7243f01520795eb005dfd1c68071130d4f920c297216439dbc8e8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-54/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-54/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=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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0c35ddf037705837be80c26cba20236d8f633cd5e59d6f9e58af3c5b41454e0a
[INFO] running `Command { std: "docker" "start" "-a" "0c35ddf037705837be80c26cba20236d8f633cd5e59d6f9e58af3c5b41454e0a", kill_on_drop: false }`
[INFO] [stderr]    Compiling koans v0.2.0 (/opt/rustwide/workdir)
[INFO] [stderr] error: failed to run custom build command for `koans v0.2.0 (/opt/rustwide/workdir)`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `/opt/rustwide/target/debug/build/koans-1d5e31a9e1d4d467/build-script-build` (exit status: 101)
[INFO] [stderr]   --- stderr
[INFO] [stderr]   thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: Os { code: 30, kind: ReadOnlyFilesystem, message: "Read-only file system" }', build.rs:7:10
[INFO] [stderr]   stack backtrace:
[INFO] [stderr]      0:     0x555b297b20e0 - std::backtrace_rs::backtrace::libunwind::trace::hff4d1766e93f64f1
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/../../backtrace/src/backtrace/libunwind.rs:90:5
[INFO] [stderr]      1:     0x555b297b20e0 - std::backtrace_rs::backtrace::trace_unsynchronized::h56bbc8eb78770bcb
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
[INFO] [stderr]      2:     0x555b297b20e0 - std::sys_common::backtrace::_print_fmt::h5c8e75464faca780
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/sys_common/backtrace.rs:67:5
[INFO] [stderr]      3:     0x555b297b20e0 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h48b88277def8b362
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/sys_common/backtrace.rs:46:22
[INFO] [stderr]      4:     0x555b297cb9bc - core::fmt::write::h3381b3176fe2b3d3
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/core/src/fmt/mod.rs:1115:17
[INFO] [stderr]      5:     0x555b297b0b75 - std::io::Write::write_fmt::hd42607e5d8e44db0
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/io/mod.rs:1665:15
[INFO] [stderr]      6:     0x555b297b3d1b - std::sys_common::backtrace::_print::ha537687d6c17dd0d
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/sys_common/backtrace.rs:49:5
[INFO] [stderr]      7:     0x555b297b3d1b - std::sys_common::backtrace::print::h61376ae57d131d72
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/sys_common/backtrace.rs:36:9
[INFO] [stderr]      8:     0x555b297b3d1b - std::panicking::default_hook::{{closure}}::h0f7208c0b9644a54
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/panicking.rs:208:50
[INFO] [stderr]      9:     0x555b297b37f1 - std::panicking::default_hook::hdac7fc06578c14ce
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/panicking.rs:225:9
[INFO] [stderr]     10:     0x555b297b43e4 - std::panicking::rust_panic_with_hook::h72b21c283da3d1ef
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/panicking.rs:622:17
[INFO] [stderr]     11:     0x555b297b3ec7 - std::panicking::begin_panic_handler::{{closure}}::he5778f1729cff84a
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/panicking.rs:519:13
[INFO] [stderr]     12:     0x555b297b25bc - std::sys_common::backtrace::__rust_end_short_backtrace::h2d11ca8b453b4b1d
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/sys_common/backtrace.rs:141:18
[INFO] [stderr]     13:     0x555b297b3e29 - rust_begin_unwind
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/panicking.rs:515:5
[INFO] [stderr]     14:     0x555b297a2e11 - core::panicking::panic_fmt::hf9de31d4acbce4db
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/core/src/panicking.rs:92:14
[INFO] [stderr]     15:     0x555b297a2ea3 - core::result::unwrap_failed::ha0c84e81219e5878
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/core/src/result.rs:1599:5
[INFO] [stderr]     16:     0x555b297a3fde - core::result::Result<T,E>::unwrap::h2a412e841455b2b8
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/core/src/result.rs:1281:23
[INFO] [stderr]     17:     0x555b297a3c51 - build_script_build::main::h3fe3646cd59b5f49
[INFO] [stderr]                                  at /opt/rustwide/workdir/build.rs:4:5
[INFO] [stderr]     18:     0x555b297a3dcb - core::ops::function::FnOnce::call_once::hc7ec624096499c41
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/core/src/ops/function.rs:227:5
[INFO] [stderr]     19:     0x555b297a3b4e - std::sys_common::backtrace::__rust_begin_short_backtrace::hbd641a838ce64066
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/sys_common/backtrace.rs:125:18
[INFO] [stderr]     20:     0x555b297a3d81 - std::rt::lang_start::{{closure}}::h84ac1024665fb34d
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/rt.rs:63:18
[INFO] [stderr]     21:     0x555b297b48ea - core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once::ha88a7d1a4d24e549
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/core/src/ops/function.rs:259:13
[INFO] [stderr]     22:     0x555b297b48ea - std::panicking::try::do_call::hd3b1d7740607ccc7
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/panicking.rs:401:40
[INFO] [stderr]     23:     0x555b297b48ea - std::panicking::try::h0ee8c65ac7461507
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/panicking.rs:365:19
[INFO] [stderr]     24:     0x555b297b48ea - std::panic::catch_unwind::head47f0de4ccd838
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/panic.rs:434:14
[INFO] [stderr]     25:     0x555b297b48ea - std::rt::lang_start_internal::{{closure}}::hbc7de8ec820ac085
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/rt.rs:45:48
[INFO] [stderr]     26:     0x555b297b48ea - std::panicking::try::do_call::h2609e52e8bad4a7b
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/panicking.rs:401:40
[INFO] [stderr]     27:     0x555b297b48ea - std::panicking::try::hd0929f0b603e0389
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/panicking.rs:365:19
[INFO] [stderr]     28:     0x555b297b48ea - std::panic::catch_unwind::h27902b81c3e47571
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/panic.rs:434:14
[INFO] [stderr]     29:     0x555b297b48ea - std::rt::lang_start_internal::h3fb2d794dd391e3e
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/rt.rs:45:20
[INFO] [stderr]     30:     0x555b297a3d50 - std::rt::lang_start::h73a4bd46b2412487
[INFO] [stderr]                                  at /rustc/53fd98ca776cb875bc9e5514f56b52eb74f9e7a9/library/std/src/rt.rs:62:5
[INFO] [stderr]     31:     0x555b297a3c8c - main
[INFO] [stderr]     32:     0x7f0226ab40b3 - __libc_start_main
[INFO] [stderr]     33:     0x555b297a356e - _start
[INFO] [stderr]     34:                0x0 - <unknown>
[INFO] running `Command { std: "docker" "inspect" "0c35ddf037705837be80c26cba20236d8f633cd5e59d6f9e58af3c5b41454e0a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0c35ddf037705837be80c26cba20236d8f633cd5e59d6f9e58af3c5b41454e0a", kill_on_drop: false }`
[INFO] [stdout] 0c35ddf037705837be80c26cba20236d8f633cd5e59d6f9e58af3c5b41454e0a
