[INFO] cloning repository https://github.com/soson/aoc_rust_2022
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/soson/aoc_rust_2022" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsoson%2Faoc_rust_2022", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsoson%2Faoc_rust_2022'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] e375656bc49a4261e578a53742b4d2369bd4932f
[INFO] testing soson/aoc_rust_2022 against 1.77.0 for beta-1.78-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsoson%2Faoc_rust_2022" "/workspace/builds/worker-2-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/soson/aoc_rust_2022 on toolchain 1.77.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.77.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/soson/aoc_rust_2022
[INFO] finished tweaking git repo https://github.com/soson/aoc_rust_2022
[INFO] tweaked toml for git repo https://github.com/soson/aoc_rust_2022 written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/soson/aoc_rust_2022 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" "+1.77.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.77.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c3b53fb81879c098f5794244c0836cb00cb513afcd67ecf14d041228fe8cabbb
[INFO] running `Command { std: "docker" "start" "-a" "c3b53fb81879c098f5794244c0836cb00cb513afcd67ecf14d041228fe8cabbb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c3b53fb81879c098f5794244c0836cb00cb513afcd67ecf14d041228fe8cabbb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c3b53fb81879c098f5794244c0836cb00cb513afcd67ecf14d041228fe8cabbb", kill_on_drop: false }`
[INFO] [stdout] c3b53fb81879c098f5794244c0836cb00cb513afcd67ecf14d041228fe8cabbb
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/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" "RUSTDOCFLAGS=--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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.77.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 34320124ab43e101d6da5107f75618f0454f93b463a327ddc44066a1557ba56e
[INFO] running `Command { std: "docker" "start" "-a" "34320124ab43e101d6da5107f75618f0454f93b463a327ddc44066a1557ba56e", kill_on_drop: false }`
[INFO] [stderr]    Compiling memchr v2.5.0
[INFO] [stderr]    Compiling regex-syntax v0.6.28
[INFO] [stderr] LLVM ERROR: IO failure on output stream: No space left on device
[INFO] [stderr] error: could not compile `memchr` (build script)
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error: error writing dependencies to `/opt/rustwide/target/debug/deps/regex_syntax-407503bc357a7624.d`: No space left on device (os error 28)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `regex-syntax` (lib) due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "34320124ab43e101d6da5107f75618f0454f93b463a327ddc44066a1557ba56e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "34320124ab43e101d6da5107f75618f0454f93b463a327ddc44066a1557ba56e", kill_on_drop: false }`
[INFO] [stdout] 34320124ab43e101d6da5107f75618f0454f93b463a327ddc44066a1557ba56e
[INFO] testing soson/aoc_rust_2022 against beta-2024-03-24 for beta-1.78-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsoson%2Faoc_rust_2022" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/soson/aoc_rust_2022 on toolchain beta-2024-03-24
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2024-03-24" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/soson/aoc_rust_2022
[INFO] finished tweaking git repo https://github.com/soson/aoc_rust_2022
[INFO] tweaked toml for git repo https://github.com/soson/aoc_rust_2022 written to /workspace/builds/worker-2-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/soson/aoc_rust_2022 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" "+beta-2024-03-24" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2024-03-24" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4c7da9f4b83c676565f02f28f78e705ce723d4df95a072dfb5b6a6fda69d7fba
[INFO] running `Command { std: "docker" "start" "-a" "4c7da9f4b83c676565f02f28f78e705ce723d4df95a072dfb5b6a6fda69d7fba", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4c7da9f4b83c676565f02f28f78e705ce723d4df95a072dfb5b6a6fda69d7fba", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4c7da9f4b83c676565f02f28f78e705ce723d4df95a072dfb5b6a6fda69d7fba", kill_on_drop: false }`
[INFO] [stdout] 4c7da9f4b83c676565f02f28f78e705ce723d4df95a072dfb5b6a6fda69d7fba
[INFO] testing soson/aoc_rust_2022 against beta-2024-03-24 for beta-1.78-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsoson%2Faoc_rust_2022" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/soson/aoc_rust_2022 on toolchain beta-2024-03-24
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2024-03-24" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/soson/aoc_rust_2022
[INFO] finished tweaking git repo https://github.com/soson/aoc_rust_2022
[INFO] tweaked toml for git repo https://github.com/soson/aoc_rust_2022 written to /workspace/builds/worker-2-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/soson/aoc_rust_2022 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" "+beta-2024-03-24" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2024-03-24" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 222095c55409b8e02c7aa516bb5b322fe08b3a3d1983850fdcc2de941a1a007b
[INFO] running `Command { std: "docker" "start" "-a" "222095c55409b8e02c7aa516bb5b322fe08b3a3d1983850fdcc2de941a1a007b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "222095c55409b8e02c7aa516bb5b322fe08b3a3d1983850fdcc2de941a1a007b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "222095c55409b8e02c7aa516bb5b322fe08b3a3d1983850fdcc2de941a1a007b", kill_on_drop: false }`
[INFO] [stdout] 222095c55409b8e02c7aa516bb5b322fe08b3a3d1983850fdcc2de941a1a007b
[INFO] testing soson/aoc_rust_2022 against beta-2024-03-24 for beta-1.78-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsoson%2Faoc_rust_2022" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/soson/aoc_rust_2022 on toolchain beta-2024-03-24
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2024-03-24" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/soson/aoc_rust_2022
[INFO] finished tweaking git repo https://github.com/soson/aoc_rust_2022
[INFO] tweaked toml for git repo https://github.com/soson/aoc_rust_2022 written to /workspace/builds/worker-2-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/soson/aoc_rust_2022 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" "+beta-2024-03-24" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2024-03-24" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b4e060404ab01c6e4345d05acaa4952f468f4b43fb920cd2a2ebc08f4e6802ed
[INFO] running `Command { std: "docker" "start" "-a" "b4e060404ab01c6e4345d05acaa4952f468f4b43fb920cd2a2ebc08f4e6802ed", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b4e060404ab01c6e4345d05acaa4952f468f4b43fb920cd2a2ebc08f4e6802ed", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b4e060404ab01c6e4345d05acaa4952f468f4b43fb920cd2a2ebc08f4e6802ed", kill_on_drop: false }`
[INFO] [stdout] b4e060404ab01c6e4345d05acaa4952f468f4b43fb920cd2a2ebc08f4e6802ed
[INFO] testing soson/aoc_rust_2022 against beta-2024-03-24 for beta-1.78-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsoson%2Faoc_rust_2022" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/soson/aoc_rust_2022 on toolchain beta-2024-03-24
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2024-03-24" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/soson/aoc_rust_2022
[INFO] finished tweaking git repo https://github.com/soson/aoc_rust_2022
[INFO] tweaked toml for git repo https://github.com/soson/aoc_rust_2022 written to /workspace/builds/worker-2-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/soson/aoc_rust_2022 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" "+beta-2024-03-24" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2024-03-24" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] Error response from daemon: mkdir /var/lib/docker/overlay2/f71732ea1ede2e40304bb9761eb0c72c76fb4df42fed855ffc24347061e3f38e/merged/opt/rustwide/workdir: no space left on device
[INFO] testing soson/aoc_rust_2022 against beta-2024-03-24 for beta-1.78-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsoson%2Faoc_rust_2022" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/soson/aoc_rust_2022 on toolchain beta-2024-03-24
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2024-03-24" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/soson/aoc_rust_2022
[INFO] finished tweaking git repo https://github.com/soson/aoc_rust_2022
[INFO] tweaked toml for git repo https://github.com/soson/aoc_rust_2022 written to /workspace/builds/worker-2-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/soson/aoc_rust_2022 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" "+beta-2024-03-24" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2024-03-24" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] Error response from daemon: mkdir /var/lib/docker/overlay2/13a135be254e8a154d6d33082781d2bf7dc6aa74727af7cfa2e29ee1cbd5e98a/merged/opt/rustwide: no space left on device
[ERROR] this task or one of its parent failed!
[ERROR] command failed: exit status: 1
[ERROR] note: run with `RUST_BACKTRACE=1` to display a backtrace.