[INFO] cloning repository https://github.com/rbran/pwn-proxy [INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/rbran/pwn-proxy" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frbran%2Fpwn-proxy", kill_on_drop: false }` [INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frbran%2Fpwn-proxy'... [INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }` [INFO] [stdout] 21994889b554ef52b05670a25b697ab6f44625fb [INFO] testing rbran/pwn-proxy against master#61223975d46f794466efa832bc7562b9707ecc46+rustflags=-Copt-level=3 for pr-121282 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frbran%2Fpwn-proxy" "/workspace/builds/worker-7-tc1/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc1/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/rbran/pwn-proxy on toolchain 61223975d46f794466efa832bc7562b9707ecc46 [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+61223975d46f794466efa832bc7562b9707ecc46" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/rbran/pwn-proxy [INFO] finished tweaking git repo https://github.com/rbran/pwn-proxy [INFO] tweaked toml for git repo https://github.com/rbran/pwn-proxy written to /workspace/builds/worker-7-tc1/source/Cargo.toml [INFO] crate git repo https://github.com/rbran/pwn-proxy 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" "+61223975d46f794466efa832bc7562b9707ecc46" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] Downloading crates ... [INFO] [stderr] Downloaded unsafe-libyaml v0.2.1 [INFO] [stderr] Downloaded serde_yaml v0.9.1 [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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" "+61223975d46f794466efa832bc7562b9707ecc46" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }` [INFO] [stdout] f94e210b58d8c8f87fdbf66e7e07d29dfeb34cd9a8ddda38ba00952bdd8b3188 [INFO] running `Command { std: "docker" "start" "-a" "f94e210b58d8c8f87fdbf66e7e07d29dfeb34cd9a8ddda38ba00952bdd8b3188", kill_on_drop: false }` [INFO] running `Command { std: "docker" "inspect" "f94e210b58d8c8f87fdbf66e7e07d29dfeb34cd9a8ddda38ba00952bdd8b3188", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "f94e210b58d8c8f87fdbf66e7e07d29dfeb34cd9a8ddda38ba00952bdd8b3188", kill_on_drop: false }` [INFO] [stdout] f94e210b58d8c8f87fdbf66e7e07d29dfeb34cd9a8ddda38ba00952bdd8b3188 [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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 -Copt-level=3" "-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+61223975d46f794466efa832bc7562b9707ecc46" "build" "--frozen" "--message-format=json", kill_on_drop: false }` [INFO] [stdout] 25a1523879c505ef01273b848fffdca1db7bd95545e9528508d7606dc19ed80b [INFO] running `Command { std: "docker" "start" "-a" "25a1523879c505ef01273b848fffdca1db7bd95545e9528508d7606dc19ed80b", kill_on_drop: false }` [INFO] [stderr] Compiling autocfg v1.1.0 [INFO] [stderr] Compiling proc-macro2 v1.0.40 [INFO] [stderr] Compiling quote v1.0.20 [INFO] [stderr] Compiling libc v0.2.126 [INFO] [stderr] Compiling unicode-ident v1.0.2 [INFO] [stderr] Compiling syn v1.0.98 [INFO] [stderr] Compiling cfg-if v1.0.0 [INFO] [stderr] Compiling parking_lot_core v0.9.3 [INFO] [stderr] Compiling serde_derive v1.0.140 [INFO] [stderr] Compiling log v0.4.17 [INFO] [stderr] Compiling radium v0.7.0 [INFO] [stderr] Compiling smallvec v1.9.0 [INFO] [stderr] Compiling serde v1.0.140 [INFO] [stderr] Compiling memchr v2.5.0 [INFO] [stderr] Compiling scopeguard v1.1.0 [INFO] [stderr] Compiling async-trait v0.1.56 [INFO] [stderr] Compiling tap v1.0.1 [INFO] [stderr] Compiling hashbrown v0.12.3 [INFO] [stderr] Compiling ryu v1.0.10 [INFO] [stderr] Compiling wyz v0.5.0 [INFO] [stderr] Compiling once_cell v1.13.0 [INFO] [stderr] Compiling funty v2.0.0 [INFO] [stderr] Compiling unsafe-libyaml v0.2.1 [INFO] [stderr] Compiling itoa v1.0.2 [INFO] [stderr] Compiling pin-project-lite v0.2.9 [INFO] [stderr] Compiling bytes v1.2.0 [INFO] [stderr] Compiling base64 v0.13.0 [INFO] [stderr] Compiling lock_api v0.4.7 [INFO] [stderr] Compiling indexmap v1.9.1 [INFO] [stderr] Compiling tokio v1.20.0 [INFO] [stderr] Compiling bitvec v1.0.1 [INFO] [stderr] Compiling num_cpus v1.13.1 [INFO] [stderr] Compiling socket2 v0.4.4 [INFO] [stderr] Compiling signal-hook-registry v1.4.0 [INFO] [stderr] Compiling mio v0.8.4 [INFO] [stderr] Compiling parking_lot v0.12.1 [INFO] [stderr] Compiling tokio-macros v1.8.0 [INFO] [stdout] error: failed to write to `/opt/rustwide/target/debug/deps/rmeta4kUmEC/lib.rmeta`: No space left on device (os error 28) [INFO] [stdout] [INFO] [stdout] [INFO] [stderr] error: could not compile `serde` (lib) due to 1 previous error [INFO] [stderr] warning: build failed, waiting for other jobs to finish... [INFO] [stdout] error: linking with `cc` failed: exit status: 1 [INFO] [stdout] | [INFO] [stdout] = note: LC_ALL="C" PATH="/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/bin:/opt/rustwide/cargo-home/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin" VSLANG="1033" "cc" "-Wl,--version-script=/tmp/rustcW6Ugqt/list" "-Wl,--no-undefined-version" "-m64" "/tmp/rustcW6Ugqt/symbols.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.00.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.01.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.02.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.03.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.04.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.05.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.06.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.07.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.08.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.09.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.10.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.11.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.12.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.13.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.14.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.async_trait.baeae7c9ac4e3140-cgu.15.rcgu.o" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.4ns6j83cht772myw.rcgu.rmeta" "/opt/rustwide/target/debug/deps/async_trait-cdedeb18682d1015.zdbdtq1h0xayi5m.rcgu.o" "-Wl,--as-needed" "-L" "/opt/rustwide/target/debug/deps" "-L" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-Wl,-Bstatic" "/opt/rustwide/target/debug/deps/libsyn-360b04fad034d314.rlib" "/opt/rustwide/target/debug/deps/libquote-3971110c7cdb06e6.rlib" "/opt/rustwide/target/debug/deps/libproc_macro2-18681fc9491b922d.rlib" "/opt/rustwide/target/debug/deps/libunicode_ident-7a1d3f32772cc436.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/libproc_macro-f63374a0cddf850a.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd-41777efa78699460.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/libpanic_unwind-c112ec61d40d65ca.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/libobject-20279e89ddf4a3cc.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/libmemchr-04ebab3d6657d9b7.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/libaddr2line-43ee38a2c180d260.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/libgimli-d8bc9f4e15c9d54f.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_demangle-e6b80df35ce800f7.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd_detect-e1bb29bdfec551bd.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/libhashbrown-7d60d25f346b95e2.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_alloc-f568bda7d014913a.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/libminiz_oxide-a759d15c36457a02.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/libadler-dd7d06242b5022a0.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/libunwind-f4343bfa39e809a4.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcfg_if-af1cb76e71c5600e.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/liblibc-8c4c4e24ed6290fa.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/liballoc-58f5eb9eff701be9.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_core-9686387289eaa322.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-632ae0f28c5e55ff.rlib" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcompiler_builtins-b7903030bc1640bf.rlib" "-Wl,-Bdynamic" "-lgcc_s" "-lutil" "-lrt" "-lpthread" "-lm" "-ldl" "-lc" "-Wl,--eh-frame-hdr" "-Wl,-z,noexecstack" "-L" "/opt/rustwide/rustup-home/toolchains/61223975d46f794466efa832bc7562b9707ecc46/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-o" "/opt/rustwide/target/debug/deps/libasync_trait-cdedeb18682d1015.so" "-Wl,--gc-sections" "-shared" "-Wl,-z,relro,-z,now" "-Wl,-O1" "-nodefaultlibs" [INFO] [stdout] = note: /usr/bin/ld: final link failed: No space left on device [INFO] [stdout] collect2: error: ld returned 1 exit status [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] error: aborting due to 1 previous error [INFO] [stdout] [INFO] [stdout] [INFO] [stderr] error: could not compile `async-trait` (lib) due to 2 previous errors [INFO] running `Command { std: "docker" "inspect" "25a1523879c505ef01273b848fffdca1db7bd95545e9528508d7606dc19ed80b", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "25a1523879c505ef01273b848fffdca1db7bd95545e9528508d7606dc19ed80b", kill_on_drop: false }` [INFO] [stdout] 25a1523879c505ef01273b848fffdca1db7bd95545e9528508d7606dc19ed80b [INFO] testing rbran/pwn-proxy against try#d073071d77ce0f93b4fd8cc567a1e2b9e1b22126+rustflags=-Copt-level=3 for pr-121282 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frbran%2Fpwn-proxy" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/rbran/pwn-proxy on toolchain d073071d77ce0f93b4fd8cc567a1e2b9e1b22126 [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+d073071d77ce0f93b4fd8cc567a1e2b9e1b22126" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/rbran/pwn-proxy [INFO] finished tweaking git repo https://github.com/rbran/pwn-proxy [INFO] tweaked toml for git repo https://github.com/rbran/pwn-proxy written to /workspace/builds/worker-7-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/rbran/pwn-proxy 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" "+d073071d77ce0f93b4fd8cc567a1e2b9e1b22126" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] testing rbran/pwn-proxy against try#d073071d77ce0f93b4fd8cc567a1e2b9e1b22126+rustflags=-Copt-level=3 for pr-121282 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frbran%2Fpwn-proxy" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'... [INFO] [stderr] done. [INFO] [stderr] fatal: unable to write new index file [INFO] [stderr] warning: Clone succeeded, but checkout failed. [INFO] [stderr] You can inspect what was checked out with 'git status' [INFO] [stderr] and retry with 'git restore --source=HEAD :/' [INFO] [stderr] [INFO] testing rbran/pwn-proxy against try#d073071d77ce0f93b4fd8cc567a1e2b9e1b22126+rustflags=-Copt-level=3 for pr-121282 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frbran%2Fpwn-proxy" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'... [INFO] [stderr] done. [INFO] [stderr] fatal: unable to write new index file [INFO] [stderr] warning: Clone succeeded, but checkout failed. [INFO] [stderr] You can inspect what was checked out with 'git status' [INFO] [stderr] and retry with 'git restore --source=HEAD :/' [INFO] [stderr] [INFO] testing rbran/pwn-proxy against try#d073071d77ce0f93b4fd8cc567a1e2b9e1b22126+rustflags=-Copt-level=3 for pr-121282 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frbran%2Fpwn-proxy" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'... [INFO] [stderr] done. [INFO] [stderr] error: unable to write file src/packet/weapon.rs [INFO] [stderr] fatal: unable to checkout working tree [INFO] [stderr] warning: Clone succeeded, but checkout failed. [INFO] [stderr] You can inspect what was checked out with 'git status' [INFO] [stderr] and retry with 'git restore --source=HEAD :/' [INFO] [stderr] [INFO] testing rbran/pwn-proxy against try#d073071d77ce0f93b4fd8cc567a1e2b9e1b22126+rustflags=-Copt-level=3 for pr-121282 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frbran%2Fpwn-proxy" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'... [INFO] [stderr] done. [INFO] [stderr] error: unable to write file src/packet/weapon.rs [INFO] [stderr] fatal: unable to checkout working tree [INFO] [stderr] warning: Clone succeeded, but checkout failed. [INFO] [stderr] You can inspect what was checked out with 'git status' [INFO] [stderr] and retry with 'git restore --source=HEAD :/' [INFO] [stderr] [ERROR] this task or one of its parent failed! [ERROR] failed to checkout https://github.com/rbran/pwn-proxy [ERROR] caused by: command failed: exit status: 128 [ERROR] note: run with `RUST_BACKTRACE=1` to display a backtrace.