[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] building alexclear/rust-koans-answers against master#881c1ac408d93bb7adaa3a51dabab9266e82eee8 for issue-85264
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Falexclear%2Frust-koans-answers" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/alexclear/rust-koans-answers on toolchain 881c1ac408d93bb7adaa3a51dabab9266e82eee8
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+881c1ac408d93bb7adaa3a51dabab9266e82eee8" "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-6/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" "+881c1ac408d93bb7adaa3a51dabab9266e82eee8" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+881c1ac408d93bb7adaa3a51dabab9266e82eee8" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d51848dba2a8cd2596266607692128e3f7f3fd17be0c6f2d7887246091e5f972
[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" "d51848dba2a8cd2596266607692128e3f7f3fd17be0c6f2d7887246091e5f972", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d51848dba2a8cd2596266607692128e3f7f3fd17be0c6f2d7887246091e5f972", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d51848dba2a8cd2596266607692128e3f7f3fd17be0c6f2d7887246091e5f972", kill_on_drop: false }`
[INFO] [stdout] d51848dba2a8cd2596266607692128e3f7f3fd17be0c6f2d7887246091e5f972
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+881c1ac408d93bb7adaa3a51dabab9266e82eee8" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 074d02747d7e6b4a5f36dc4db1c3bc75397bea4353db5b4379f3b5be13d77fb4
[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" "074d02747d7e6b4a5f36dc4db1c3bc75397bea4353db5b4379f3b5be13d77fb4", 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-dd4c58307ba92316/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: Other, message: "Read-only file system" }', build.rs:7:10
[INFO] [stderr]   stack backtrace:
[INFO] [stderr]      0:     0x5606cad48100 - std::backtrace_rs::backtrace::libunwind::trace::hdcf4f90f85129e83
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/../../backtrace/src/backtrace/libunwind.rs:90:5
[INFO] [stderr]      1:     0x5606cad48100 - std::backtrace_rs::backtrace::trace_unsynchronized::h2669e30cb82f6732
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
[INFO] [stderr]      2:     0x5606cad48100 - std::sys_common::backtrace::_print_fmt::hfbda19e17f6db318
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/sys_common/backtrace.rs:67:5
[INFO] [stderr]      3:     0x5606cad48100 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h1a8751bf59281272
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/sys_common/backtrace.rs:46:22
[INFO] [stderr]      4:     0x5606cad6211f - core::fmt::write::h7aa6cd0067dca82a
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/core/src/fmt/mod.rs:1094:17
[INFO] [stderr]      5:     0x5606cad46a45 - std::io::Write::write_fmt::hd7dd3a1df9b6befb
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/io/mod.rs:1584:15
[INFO] [stderr]      6:     0x5606cad49d3b - std::sys_common::backtrace::_print::h551e9ec8a9fa8106
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/sys_common/backtrace.rs:49:5
[INFO] [stderr]      7:     0x5606cad49d3b - std::sys_common::backtrace::print::ha4b1c5e95fa040b3
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/sys_common/backtrace.rs:36:9
[INFO] [stderr]      8:     0x5606cad49d3b - std::panicking::default_hook::{{closure}}::h0b34c9ab7fb9f857
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/panicking.rs:208:50
[INFO] [stderr]      9:     0x5606cad4981d - std::panicking::default_hook::h3067e8318decd17a
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/panicking.rs:225:9
[INFO] [stderr]     10:     0x5606cad4a2ed - std::panicking::rust_panic_with_hook::h81b8facc50f34daa
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/panicking.rs:591:17
[INFO] [stderr]     11:     0x5606cad49ee7 - std::panicking::begin_panic_handler::{{closure}}::ha376ab85d95a000e
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/panicking.rs:497:13
[INFO] [stderr]     12:     0x5606cad485bc - std::sys_common::backtrace::__rust_end_short_backtrace::h6795c8afdd1a77e6
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/sys_common/backtrace.rs:141:18
[INFO] [stderr]     13:     0x5606cad49e49 - rust_begin_unwind
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/panicking.rs:493:5
[INFO] [stderr]     14:     0x5606cad38dc1 - core::panicking::panic_fmt::hbe99dddd3092ba3c
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/core/src/panicking.rs:92:14
[INFO] [stderr]     15:     0x5606cad38e53 - core::result::unwrap_failed::hf79563fef9d11ab8
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/core/src/result.rs:1355:5
[INFO] [stderr]     16:     0x5606cad39efa - core::result::Result<T,E>::unwrap::hd481895943b1bf1f
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/core/src/result.rs:1037:23
[INFO] [stderr]     17:     0x5606cad39d31 - build_script_build::main::h59632e704e81bd39
[INFO] [stderr]                                  at /opt/rustwide/workdir/build.rs:4:5
[INFO] [stderr]     18:     0x5606cad39afb - core::ops::function::FnOnce::call_once::hfaef590dca4e7c45
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/core/src/ops/function.rs:227:5
[INFO] [stderr]     19:     0x5606cad399de - std::sys_common::backtrace::__rust_begin_short_backtrace::h1a07b7f012b18aed
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/sys_common/backtrace.rs:125:18
[INFO] [stderr]     20:     0x5606cad39dc1 - std::rt::lang_start::{{closure}}::h23b86d01c11ef6b7
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/rt.rs:49:18
[INFO] [stderr]     21:     0x5606cad4a6ea - core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once::h3b8c329143d7638a
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/core/src/ops/function.rs:259:13
[INFO] [stderr]     22:     0x5606cad4a6ea - std::panicking::try::do_call::h4b72c261b4eefc1b
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/panicking.rs:379:40
[INFO] [stderr]     23:     0x5606cad4a6ea - std::panicking::try::h703d31b7896cbd49
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/panicking.rs:343:19
[INFO] [stderr]     24:     0x5606cad4a6ea - std::panic::catch_unwind::h37cad9b35388a915
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/panic.rs:431:14
[INFO] [stderr]     25:     0x5606cad4a6ea - std::rt::lang_start_internal::hab5a8a909af4f90e
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/rt.rs:34:21
[INFO] [stderr]     26:     0x5606cad39da0 - std::rt::lang_start::h030dca7db877b21d
[INFO] [stderr]                                  at /rustc/881c1ac408d93bb7adaa3a51dabab9266e82eee8/library/std/src/rt.rs:48:5
[INFO] [stderr]     27:     0x5606cad39d6c - main
[INFO] [stderr]     28:     0x7f162e7d90b3 - __libc_start_main
[INFO] [stderr]     29:     0x5606cad394be - _start
[INFO] [stderr]     30:                0x0 - <unknown>
[INFO] running `Command { std: "docker" "inspect" "074d02747d7e6b4a5f36dc4db1c3bc75397bea4353db5b4379f3b5be13d77fb4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "074d02747d7e6b4a5f36dc4db1c3bc75397bea4353db5b4379f3b5be13d77fb4", kill_on_drop: false }`
[INFO] [stdout] 074d02747d7e6b4a5f36dc4db1c3bc75397bea4353db5b4379f3b5be13d77fb4
