[INFO] cloning repository https://github.com/JScearcy/Rust-Koans
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/JScearcy/Rust-Koans" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJScearcy%2FRust-Koans", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJScearcy%2FRust-Koans'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] cb4bceeb057657f833916c019f96605c7170382c
[INFO] checking JScearcy/Rust-Koans against try#9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c for pr-79472
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJScearcy%2FRust-Koans" "/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/JScearcy/Rust-Koans on toolchain 9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/JScearcy/Rust-Koans
[INFO] finished tweaking git repo https://github.com/JScearcy/Rust-Koans
[INFO] tweaked toml for git repo https://github.com/JScearcy/Rust-Koans written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] crate git repo https://github.com/JScearcy/Rust-Koans already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3dfa5627074f2778930ed42314f400bc3486eeb67be267a23e12251617c9f587
[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" "3dfa5627074f2778930ed42314f400bc3486eeb67be267a23e12251617c9f587", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3dfa5627074f2778930ed42314f400bc3486eeb67be267a23e12251617c9f587", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3dfa5627074f2778930ed42314f400bc3486eeb67be267a23e12251617c9f587", kill_on_drop: false }`
[INFO] [stdout] 3dfa5627074f2778930ed42314f400bc3486eeb67be267a23e12251617c9f587
[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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 12e5bd7ec0028759c92cc8e8f44dbf1afcdb4c59b132b2e4b16095b22dd2a5d8
[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" "12e5bd7ec0028759c92cc8e8f44dbf1afcdb4c59b132b2e4b16095b22dd2a5d8", 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-87891042a0e7e264/build-script-build` (exit code: 101)
[INFO] [stderr]   --- stderr
[INFO] [stderr]   thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: Os { code: 30, kind: Other, message: "Read-only file system" }', build.rs:7:10
[INFO] [stderr]   stack backtrace:
[INFO] [stderr]      0:     0x55642a0697a0 - std::backtrace_rs::backtrace::libunwind::trace::h746c3e9529d524bc
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/../../backtrace/src/backtrace/libunwind.rs:90:5
[INFO] [stderr]      1:     0x55642a0697a0 - std::backtrace_rs::backtrace::trace_unsynchronized::h86340908ff889faa
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
[INFO] [stderr]      2:     0x55642a0697a0 - std::sys_common::backtrace::_print_fmt::h43f85f9b18230404
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/sys_common/backtrace.rs:67:5
[INFO] [stderr]      3:     0x55642a0697a0 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hc132ae1a5b5aa7cd
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/sys_common/backtrace.rs:46:22
[INFO] [stderr]      4:     0x55642a083d1c - core::fmt::write::hdf023a0036d2a25f
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/core/src/fmt/mod.rs:1078:17
[INFO] [stderr]      5:     0x55642a067bf2 - std::io::Write::write_fmt::h8580846154bcb66a
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/io/mod.rs:1519:15
[INFO] [stderr]      6:     0x55642a06b4d5 - std::sys_common::backtrace::_print::h7ee55fed88d107a3
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/sys_common/backtrace.rs:49:5
[INFO] [stderr]      7:     0x55642a06b4d5 - std::sys_common::backtrace::print::h54a7d3e52a524177
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/sys_common/backtrace.rs:36:9
[INFO] [stderr]      8:     0x55642a06b4d5 - std::panicking::default_hook::{{closure}}::h60921e857bf55a40
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/panicking.rs:208:50
[INFO] [stderr]      9:     0x55642a06b02a - std::panicking::default_hook::hf0f9afb1017317fc
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/panicking.rs:225:9
[INFO] [stderr]     10:     0x55642a06bc71 - std::panicking::rust_panic_with_hook::h8d66bf42b407aaea
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/panicking.rs:591:17
[INFO] [stderr]     11:     0x55642a06b7b7 - std::panicking::begin_panic_handler::{{closure}}::hde71edcd925d0c5e
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/panicking.rs:497:13
[INFO] [stderr]     12:     0x55642a069c5c - std::sys_common::backtrace::__rust_end_short_backtrace::h8a3c7d6cea578919
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/sys_common/backtrace.rs:141:18
[INFO] [stderr]     13:     0x55642a06b719 - rust_begin_unwind
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/panicking.rs:493:5
[INFO] [stderr]     14:     0x55642a0830c1 - core::panicking::panic_fmt::h20225113c4a2f8fd
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/core/src/panicking.rs:92:14
[INFO] [stderr]     15:     0x55642a082ee3 - core::option::expect_none_failed::hc6d6d4cea4fdc285
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/core/src/option.rs:1268:5
[INFO] [stderr]     16:     0x55642a058bbb - core::result::Result<T,E>::unwrap::h8f56d13ca4abae59
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/core/src/result.rs:973:23
[INFO] [stderr]     17:     0x55642a058a57 - build_script_build::main::h2d5c5168c5a1a5a6
[INFO] [stderr]                                  at /opt/rustwide/workdir/build.rs:4:5
[INFO] [stderr]     18:     0x55642a05877b - core::ops::function::FnOnce::call_once::hde5baf7d4097ac32
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/core/src/ops/function.rs:227:5
[INFO] [stderr]     19:     0x55642a05863e - std::sys_common::backtrace::__rust_begin_short_backtrace::h188b31dc0305d79f
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/sys_common/backtrace.rs:125:18
[INFO] [stderr]     20:     0x55642a0589b1 - std::rt::lang_start::{{closure}}::h27bd22285a5ca98e
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/rt.rs:66:18
[INFO] [stderr]     21:     0x55642a06c097 - core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once::h54c39b9b8451875a
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/core/src/ops/function.rs:259:13
[INFO] [stderr]     22:     0x55642a06c097 - std::panicking::try::do_call::hcdfba51a06e21b42
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/panicking.rs:379:40
[INFO] [stderr]     23:     0x55642a06c097 - std::panicking::try::hb36953ccd24f930d
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/panicking.rs:343:19
[INFO] [stderr]     24:     0x55642a06c097 - std::panic::catch_unwind::hbb374cd03beb3824
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/panic.rs:396:14
[INFO] [stderr]     25:     0x55642a06c097 - std::rt::lang_start_internal::h97dca9624db2aa85
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/rt.rs:51:25
[INFO] [stderr]     26:     0x55642a058987 - std::rt::lang_start::h057e725eda069a20
[INFO] [stderr]                                  at /rustc/9b49d8c6c904f63eb486fe51b14bbe0aa2feda4c/library/std/src/rt.rs:65:5
[INFO] [stderr]     27:     0x55642a058a9a - main
[INFO] [stderr]     28:     0x7f90c35440b3 - __libc_start_main
[INFO] [stderr]     29:     0x55642a05809e - _start
[INFO] [stderr]     30:                0x0 - <unknown>
[INFO] running `Command { std: "docker" "inspect" "12e5bd7ec0028759c92cc8e8f44dbf1afcdb4c59b132b2e4b16095b22dd2a5d8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "12e5bd7ec0028759c92cc8e8f44dbf1afcdb4c59b132b2e4b16095b22dd2a5d8", kill_on_drop: false }`
[INFO] [stdout] 12e5bd7ec0028759c92cc8e8f44dbf1afcdb4c59b132b2e4b16095b22dd2a5d8