[INFO] cloning repository https://github.com/ryanmr/actix-web-playground [INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ryanmr/actix-web-playground" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fryanmr%2Factix-web-playground", kill_on_drop: false }` [INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fryanmr%2Factix-web-playground'... [INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }` [INFO] [stdout] 04805e41ad2042064a5fe7db0fda7e568a619028 [INFO] checking ryanmr/actix-web-playground against master#83dcdb3a5dad0ed1e3e1fadc848d3f7727b41aa5 for pr-128425 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fryanmr%2Factix-web-playground" "/workspace/builds/worker-0-tc1/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc1/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/ryanmr/actix-web-playground on toolchain 83dcdb3a5dad0ed1e3e1fadc848d3f7727b41aa5 [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+83dcdb3a5dad0ed1e3e1fadc848d3f7727b41aa5" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/ryanmr/actix-web-playground [INFO] finished tweaking git repo https://github.com/ryanmr/actix-web-playground [INFO] tweaked toml for git repo https://github.com/ryanmr/actix-web-playground written to /workspace/builds/worker-0-tc1/source/Cargo.toml [INFO] crate git repo https://github.com/ryanmr/actix-web-playground 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" "+83dcdb3a5dad0ed1e3e1fadc848d3f7727b41aa5" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+83dcdb3a5dad0ed1e3e1fadc848d3f7727b41aa5" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }` [INFO] [stdout] 68d5f2d243f69762e8f4e2140deefb7a6c4b68215911622f5adf48dcab7a6600 [INFO] running `Command { std: "docker" "start" "-a" "68d5f2d243f69762e8f4e2140deefb7a6c4b68215911622f5adf48dcab7a6600", kill_on_drop: false }` [INFO] running `Command { std: "docker" "inspect" "68d5f2d243f69762e8f4e2140deefb7a6c4b68215911622f5adf48dcab7a6600", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "68d5f2d243f69762e8f4e2140deefb7a6c4b68215911622f5adf48dcab7a6600", kill_on_drop: false }` [INFO] [stdout] 68d5f2d243f69762e8f4e2140deefb7a6c4b68215911622f5adf48dcab7a6600 [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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=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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+83dcdb3a5dad0ed1e3e1fadc848d3f7727b41aa5" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }` [INFO] [stdout] 9120dcde1e7a0d38c4fe0f122218c88421ee6f2608d909df7778cdd39221ba9a [INFO] running `Command { std: "docker" "start" "-a" "9120dcde1e7a0d38c4fe0f122218c88421ee6f2608d909df7778cdd39221ba9a", kill_on_drop: false }` [INFO] [stderr] error: failed to create directory `/opt/rustwide/target/debug/build/proc-macro2-beffb875393f6475/out` [INFO] [stderr] [INFO] [stderr] Caused by: [INFO] [stderr] No space left on device (os error 28) [INFO] running `Command { std: "docker" "inspect" "9120dcde1e7a0d38c4fe0f122218c88421ee6f2608d909df7778cdd39221ba9a", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "9120dcde1e7a0d38c4fe0f122218c88421ee6f2608d909df7778cdd39221ba9a", kill_on_drop: false }` [INFO] [stdout] 9120dcde1e7a0d38c4fe0f122218c88421ee6f2608d909df7778cdd39221ba9a [INFO] checking ryanmr/actix-web-playground against try#063c08dd8db6ff113bb809c130456f1781abe72c for pr-128425 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fryanmr%2Factix-web-playground" "/workspace/builds/worker-0-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/ryanmr/actix-web-playground on toolchain 063c08dd8db6ff113bb809c130456f1781abe72c [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+063c08dd8db6ff113bb809c130456f1781abe72c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/ryanmr/actix-web-playground [INFO] finished tweaking git repo https://github.com/ryanmr/actix-web-playground [INFO] tweaked toml for git repo https://github.com/ryanmr/actix-web-playground written to /workspace/builds/worker-0-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/ryanmr/actix-web-playground 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" "+063c08dd8db6ff113bb809c130456f1781abe72c" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+063c08dd8db6ff113bb809c130456f1781abe72c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }` [INFO] [stdout] 94047c9236427c7f840b5834207e880cd466d30455e8e9dd9c5ff5b201b027d7 [INFO] running `Command { std: "docker" "start" "-a" "94047c9236427c7f840b5834207e880cd466d30455e8e9dd9c5ff5b201b027d7", kill_on_drop: false }` [INFO] running `Command { std: "docker" "inspect" "94047c9236427c7f840b5834207e880cd466d30455e8e9dd9c5ff5b201b027d7", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "94047c9236427c7f840b5834207e880cd466d30455e8e9dd9c5ff5b201b027d7", kill_on_drop: false }` [INFO] [stdout] 94047c9236427c7f840b5834207e880cd466d30455e8e9dd9c5ff5b201b027d7 [INFO] checking ryanmr/actix-web-playground against try#063c08dd8db6ff113bb809c130456f1781abe72c for pr-128425 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fryanmr%2Factix-web-playground" "/workspace/builds/worker-0-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/ryanmr/actix-web-playground on toolchain 063c08dd8db6ff113bb809c130456f1781abe72c [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+063c08dd8db6ff113bb809c130456f1781abe72c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/ryanmr/actix-web-playground [INFO] finished tweaking git repo https://github.com/ryanmr/actix-web-playground [INFO] tweaked toml for git repo https://github.com/ryanmr/actix-web-playground written to /workspace/builds/worker-0-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/ryanmr/actix-web-playground 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" "+063c08dd8db6ff113bb809c130456f1781abe72c" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+063c08dd8db6ff113bb809c130456f1781abe72c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }` [INFO] [stdout] 8915c78500ec77e1609e89840345d521f4f7cff2412abb21477ceae03dd98af1 [INFO] running `Command { std: "docker" "start" "-a" "8915c78500ec77e1609e89840345d521f4f7cff2412abb21477ceae03dd98af1", kill_on_drop: false }` [INFO] running `Command { std: "docker" "inspect" "8915c78500ec77e1609e89840345d521f4f7cff2412abb21477ceae03dd98af1", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "8915c78500ec77e1609e89840345d521f4f7cff2412abb21477ceae03dd98af1", kill_on_drop: false }` [INFO] [stdout] 8915c78500ec77e1609e89840345d521f4f7cff2412abb21477ceae03dd98af1 [INFO] checking ryanmr/actix-web-playground against try#063c08dd8db6ff113bb809c130456f1781abe72c for pr-128425 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fryanmr%2Factix-web-playground" "/workspace/builds/worker-0-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/ryanmr/actix-web-playground on toolchain 063c08dd8db6ff113bb809c130456f1781abe72c [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+063c08dd8db6ff113bb809c130456f1781abe72c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/ryanmr/actix-web-playground [INFO] finished tweaking git repo https://github.com/ryanmr/actix-web-playground [INFO] tweaked toml for git repo https://github.com/ryanmr/actix-web-playground written to /workspace/builds/worker-0-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/ryanmr/actix-web-playground 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" "+063c08dd8db6ff113bb809c130456f1781abe72c" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+063c08dd8db6ff113bb809c130456f1781abe72c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }` [INFO] [stderr] Error response from daemon: write /var/lib/docker/containers/80fbc3b1b87ec57e313c21a331dbaa930f8b19fac1e2c262d7f4dfa8dd14c4eb/.tmp-hostconfig.json207286102: no space left on device [INFO] checking ryanmr/actix-web-playground against try#063c08dd8db6ff113bb809c130456f1781abe72c for pr-128425 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fryanmr%2Factix-web-playground" "/workspace/builds/worker-0-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/ryanmr/actix-web-playground on toolchain 063c08dd8db6ff113bb809c130456f1781abe72c [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+063c08dd8db6ff113bb809c130456f1781abe72c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/ryanmr/actix-web-playground [INFO] finished tweaking git repo https://github.com/ryanmr/actix-web-playground [INFO] tweaked toml for git repo https://github.com/ryanmr/actix-web-playground written to /workspace/builds/worker-0-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/ryanmr/actix-web-playground 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" "+063c08dd8db6ff113bb809c130456f1781abe72c" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+063c08dd8db6ff113bb809c130456f1781abe72c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }` [INFO] [stderr] Error response from daemon: mkdir /var/lib/docker/overlay2/99cdb71332c7c0f57a423e155a6fac1ba12ead8b5c096acc76414c3bc805b063/merged/opt/rustwide: no space left on device [INFO] checking ryanmr/actix-web-playground against try#063c08dd8db6ff113bb809c130456f1781abe72c for pr-128425 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fryanmr%2Factix-web-playground" "/workspace/builds/worker-0-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/ryanmr/actix-web-playground on toolchain 063c08dd8db6ff113bb809c130456f1781abe72c [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+063c08dd8db6ff113bb809c130456f1781abe72c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/ryanmr/actix-web-playground [INFO] finished tweaking git repo https://github.com/ryanmr/actix-web-playground [INFO] tweaked toml for git repo https://github.com/ryanmr/actix-web-playground written to /workspace/builds/worker-0-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/ryanmr/actix-web-playground 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" "+063c08dd8db6ff113bb809c130456f1781abe72c" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+063c08dd8db6ff113bb809c130456f1781abe72c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }` [INFO] [stderr] Error response from daemon: chown /var/lib/docker/overlay2/7bcaad3dfb7eb669943d60583f3773ede0f72c90ca218329265376ae0d5b9900/work/work: no such file or directory [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.