[INFO] cloning repository https://github.com/Undin/check-rustc-version
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Undin/check-rustc-version" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FUndin%2Fcheck-rustc-version", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FUndin%2Fcheck-rustc-version'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 654ef80d5b53f30f04d71016277543e87e898ef3
[INFO] checking Undin/check-rustc-version against master#e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682 for beta-170-4
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FUndin%2Fcheck-rustc-version" "/workspace/builds/worker-3-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Undin/check-rustc-version on toolchain e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Undin/check-rustc-version
[INFO] finished tweaking git repo https://github.com/Undin/check-rustc-version
[INFO] tweaked toml for git repo https://github.com/Undin/check-rustc-version written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/Undin/check-rustc-version 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" "+e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/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@sha256:19e73879b68f455e41552ea35293514db52ea292d993f571636dbffedb77a1ee" "/opt/rustwide/cargo-home/bin/cargo" "+e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8a8d677260ce7a0d6283812d332d219bbdfe9e6f64abd3d1bd1016ec5474ee28
[INFO] running `Command { std: "docker" "start" "-a" "8a8d677260ce7a0d6283812d332d219bbdfe9e6f64abd3d1bd1016ec5474ee28", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8a8d677260ce7a0d6283812d332d219bbdfe9e6f64abd3d1bd1016ec5474ee28", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8a8d677260ce7a0d6283812d332d219bbdfe9e6f64abd3d1bd1016ec5474ee28", kill_on_drop: false }`
[INFO] [stdout] 8a8d677260ce7a0d6283812d332d219bbdfe9e6f64abd3d1bd1016ec5474ee28
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/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" "RUSTDOCFLAGS=--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@sha256:19e73879b68f455e41552ea35293514db52ea292d993f571636dbffedb77a1ee" "/opt/rustwide/cargo-home/bin/cargo" "+e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 468f846816161ffa700b63175fd95ca921ec0f753755588af6c54bdecfb78464
[INFO] running `Command { std: "docker" "start" "-a" "468f846816161ffa700b63175fd95ca921ec0f753755588af6c54bdecfb78464", kill_on_drop: false }`
[INFO] [stderr]    Compiling check-rustc-version v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> build.rs:16:5
[INFO] [stdout]    |
[INFO] [stdout] 16 |     write!(&mut file, "RUSTC: {}\n", env::var_os("RUSTC").unwrap().to_string_lossy());
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this warning originates in the macro `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> build.rs:18:5
[INFO] [stdout]    |
[INFO] [stdout] 18 |     write!(&mut file, "rustc --version: {}\n", version);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: this warning originates in the macro `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: failed to run custom build command for `check-rustc-version v0.1.0 (/opt/rustwide/workdir)`
[INFO] [stderr] note: To improve backtraces for build dependencies, set the CARGO_PROFILE_DEV_BUILD_OVERRIDE_DEBUG=true environment variable to enable debug information generation.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `/opt/rustwide/target/debug/build/check-rustc-version-ac5380da3a792fd2/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:15:54
[INFO] [stderr]   stack backtrace:
[INFO] [stderr]      0:     0x563e4c025921 - std::backtrace_rs::backtrace::libunwind::trace::ha9d9de1bf4176bfa
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
[INFO] [stderr]      1:     0x563e4c025921 - std::backtrace_rs::backtrace::trace_unsynchronized::h165c36ef694ada1c
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
[INFO] [stderr]      2:     0x563e4c025921 - std::sys_common::backtrace::_print_fmt::h4d89c7ce1e89b43d
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/sys_common/backtrace.rs:65:5
[INFO] [stderr]      3:     0x563e4c025921 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hfc68e8a2f3b7b37c
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/sys_common/backtrace.rs:44:22
[INFO] [stderr]      4:     0x563e4c04490f - core::fmt::rt::Argument::fmt::hc7dd5538f3de21b7
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/core/src/fmt/rt.rs:138:9
[INFO] [stderr]      5:     0x563e4c04490f - core::fmt::write::hac9705ca9b43c249
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/core/src/fmt/mod.rs:1094:21
[INFO] [stderr]      6:     0x563e4c0237e1 - std::io::Write::write_fmt::h7bc9466b47d6774b
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/io/mod.rs:1713:15
[INFO] [stderr]      7:     0x563e4c025735 - std::sys_common::backtrace::_print::h03072469d8150f3e
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/sys_common/backtrace.rs:47:5
[INFO] [stderr]      8:     0x563e4c025735 - std::sys_common::backtrace::print::hd0f67791f02b87ae
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/sys_common/backtrace.rs:34:9
[INFO] [stderr]      9:     0x563e4c026ab7 - std::panicking::default_hook::{{closure}}::h7c8ccb2c703d1528
[INFO] [stderr]     10:     0x563e4c0268a4 - std::panicking::default_hook::h770c31d58b53801e
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/panicking.rs:288:9
[INFO] [stderr]     11:     0x563e4c026f6c - std::panicking::rust_panic_with_hook::hb50e58c42f5187f2
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/panicking.rs:705:13
[INFO] [stderr]     12:     0x563e4c026e67 - std::panicking::begin_panic_handler::{{closure}}::h4d6093b91efbd52e
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/panicking.rs:597:13
[INFO] [stderr]     13:     0x563e4c025d56 - std::sys_common::backtrace::__rust_end_short_backtrace::h318963d1ef4510cb
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/sys_common/backtrace.rs:151:18
[INFO] [stderr]     14:     0x563e4c026bb2 - rust_begin_unwind
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/panicking.rs:593:5
[INFO] [stderr]     15:     0x563e4c003ef3 - core::panicking::panic_fmt::h6ce9f4b93775846b
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/core/src/panicking.rs:67:14
[INFO] [stderr]     16:     0x563e4c0042d3 - core::result::unwrap_failed::h45c53cbae19f42f6
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/core/src/result.rs:1651:5
[INFO] [stderr]     17:     0x563e4c006a74 - core::result::Result<T,E>::unwrap::hf0f933f86de2b5cd
[INFO] [stderr]     18:     0x563e4c006279 - build_script_build::extract_rustc_version::h0646c98f711cf6f4
[INFO] [stderr]     19:     0x563e4c006116 - build_script_build::main::hd2f3a3c5b3c41394
[INFO] [stderr]     20:     0x563e4c007bc3 - core::ops::function::FnOnce::call_once::h044b2e1b7d17618d
[INFO] [stderr]     21:     0x563e4c0065c6 - std::sys_common::backtrace::__rust_begin_short_backtrace::hd45a9e17dc00f83b
[INFO] [stderr]     22:     0x563e4c006009 - std::rt::lang_start::{{closure}}::h5449dac5ec6c1b22
[INFO] [stderr]     23:     0x563e4c020cb5 - core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once::hb332f02ff9fc81e2
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/core/src/ops/function.rs:284:13
[INFO] [stderr]     24:     0x563e4c020cb5 - std::panicking::try::do_call::hed879afea606d968
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/panicking.rs:500:40
[INFO] [stderr]     25:     0x563e4c020cb5 - std::panicking::try::h395a878f3e4bd2f0
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/panicking.rs:464:19
[INFO] [stderr]     26:     0x563e4c020cb5 - std::panic::catch_unwind::hb44b6ea043448d57
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/panic.rs:142:14
[INFO] [stderr]     27:     0x563e4c020cb5 - std::rt::lang_start_internal::{{closure}}::h6184ba9e5b3e5fbf
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/rt.rs:148:48
[INFO] [stderr]     28:     0x563e4c020cb5 - std::panicking::try::do_call::h8b2c97d4d3608274
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/panicking.rs:500:40
[INFO] [stderr]     29:     0x563e4c020cb5 - std::panicking::try::hfa4cc536e097f1fe
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/panicking.rs:464:19
[INFO] [stderr]     30:     0x563e4c020cb5 - std::panic::catch_unwind::ha3e2192625bb4844
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/panic.rs:142:14
[INFO] [stderr]     31:     0x563e4c020cb5 - std::rt::lang_start_internal::hbd6687884d030770
[INFO] [stderr]                                  at /rustc/e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682/library/std/src/rt.rs:148:20
[INFO] [stderr]     32:     0x563e4c005fe7 - std::rt::lang_start::hcc6aad2f4c1dde0c
[INFO] [stderr]     33:     0x563e4c0065b5 - main
[INFO] [stderr]     34:     0x7f2817d13d90 - <unknown>
[INFO] [stderr]     35:     0x7f2817d13e40 - __libc_start_main
[INFO] [stderr]     36:     0x563e4c004555 - _start
[INFO] [stderr]     37:                0x0 - <unknown>
[INFO] running `Command { std: "docker" "inspect" "468f846816161ffa700b63175fd95ca921ec0f753755588af6c54bdecfb78464", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "468f846816161ffa700b63175fd95ca921ec0f753755588af6c54bdecfb78464", kill_on_drop: false }`
[INFO] [stdout] 468f846816161ffa700b63175fd95ca921ec0f753755588af6c54bdecfb78464
