[INFO] cloning repository https://github.com/KasperG21/top_down_defense_game [INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/KasperG21/top_down_defense_game" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKasperG21%2Ftop_down_defense_game", kill_on_drop: false }` [INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKasperG21%2Ftop_down_defense_game'... [INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }` [INFO] [stdout] 5334b7b3fed87d499e45121300b52dafeab9a2b3 [INFO] checking KasperG21/top_down_defense_game against master#aa067fb984d36462548bb785da221bfaf38253f0 for pr-122470 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKasperG21%2Ftop_down_defense_game" "/workspace/builds/worker-5-tc1/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc1/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/KasperG21/top_down_defense_game on toolchain aa067fb984d36462548bb785da221bfaf38253f0 [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+aa067fb984d36462548bb785da221bfaf38253f0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/KasperG21/top_down_defense_game [INFO] finished tweaking git repo https://github.com/KasperG21/top_down_defense_game [INFO] tweaked toml for git repo https://github.com/KasperG21/top_down_defense_game written to /workspace/builds/worker-5-tc1/source/Cargo.toml [INFO] crate git repo https://github.com/KasperG21/top_down_defense_game 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" "+aa067fb984d36462548bb785da221bfaf38253f0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] Blocking waiting for file lock on package cache [INFO] [stderr] Blocking waiting for file lock on package cache [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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" "+aa067fb984d36462548bb785da221bfaf38253f0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }` [INFO] [stdout] ac07ee45b6cf6e60b78dbf1c9214b7eb90108919197289b6e32c09eee2783c0c [INFO] running `Command { std: "docker" "start" "-a" "ac07ee45b6cf6e60b78dbf1c9214b7eb90108919197289b6e32c09eee2783c0c", kill_on_drop: false }` [INFO] running `Command { std: "docker" "inspect" "ac07ee45b6cf6e60b78dbf1c9214b7eb90108919197289b6e32c09eee2783c0c", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "ac07ee45b6cf6e60b78dbf1c9214b7eb90108919197289b6e32c09eee2783c0c", kill_on_drop: false }` [INFO] [stdout] ac07ee45b6cf6e60b78dbf1c9214b7eb90108919197289b6e32c09eee2783c0c [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+aa067fb984d36462548bb785da221bfaf38253f0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }` [INFO] [stdout] c196a70d2bc7ca81a75c7c053d6f028791cb365525c97298615b1e7a24d073e5 [INFO] running `Command { std: "docker" "start" "-a" "c196a70d2bc7ca81a75c7c053d6f028791cb365525c97298615b1e7a24d073e5", kill_on_drop: false }` [INFO] [stderr] Compiling sdl2-sys v0.35.2 [INFO] [stderr] Compiling libc v0.2.144 [INFO] [stderr] Compiling serde v1.0.164 [INFO] [stderr] Compiling sdl2 v0.35.2 [INFO] [stderr] Compiling serde_json v1.0.96 [INFO] [stderr] Checking barney_defense v0.1.0 (/opt/rustwide/workdir) [INFO] [stdout] warning: the item `serde_json` is imported redundantly [INFO] [stdout] --> src/main.rs:3:5 [INFO] [stdout] | [INFO] [stdout] 3 | use serde_json; [INFO] [stdout] | ^^^^^^^^^^ the item `serde_json` is already defined by prelude [INFO] [stdout] | [INFO] [stdout] = note: `#[warn(unused_imports)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: the item `sdl2` is imported redundantly [INFO] [stdout] --> src/main.rs:7:5 [INFO] [stdout] | [INFO] [stdout] 7 | self, [INFO] [stdout] | ^^^^ the item `sdl2` is already defined by prelude [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: the item `sdl2` is imported redundantly [INFO] [stdout] --> src/initialization.rs:3:16 [INFO] [stdout] | [INFO] [stdout] 3 | use sdl2::{self, render::Canvas, EventPump, video}; [INFO] [stdout] | ^^^^ the item `sdl2` is already defined by prelude [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: the item `serde_json` is imported redundantly [INFO] [stdout] --> src/main.rs:3:5 [INFO] [stdout] | [INFO] [stdout] 3 | use serde_json; [INFO] [stdout] | ^^^^^^^^^^ the item `serde_json` is already defined by prelude [INFO] [stdout] | [INFO] [stdout] = note: `#[warn(unused_imports)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: the item `sdl2` is imported redundantly [INFO] [stdout] --> src/main.rs:7:5 [INFO] [stdout] | [INFO] [stdout] 7 | self, [INFO] [stdout] | ^^^^ the item `sdl2` is already defined by prelude [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: the item `sdl2` is imported redundantly [INFO] [stdout] --> src/initialization.rs:3:16 [INFO] [stdout] | [INFO] [stdout] 3 | use sdl2::{self, render::Canvas, EventPump, video}; [INFO] [stdout] | ^^^^ the item `sdl2` is already defined by prelude [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] error[E0283]: type annotations needed [INFO] [stdout] --> src/main.rs:294:36 [INFO] [stdout] | [INFO] [stdout] 294 | let data = serde_json::from_str(&raw_json); [INFO] [stdout] | ^^^^^^^^^^^^^^^^^^^^ cannot infer type of the type parameter `T` declared on the function `from_str` [INFO] [stdout] | [INFO] [stdout] = note: cannot satisfy `_: serde::de::Deserialize<'_>` [INFO] [stdout] = help: the following types implement trait `serde::de::Deserialize<'de>`: [INFO] [stdout] &'a Path [INFO] [stdout] &'a [u8] [INFO] [stdout] &'a str [INFO] [stdout] () [INFO] [stdout] (T0, T1) [INFO] [stdout] (T0, T1, T2) [INFO] [stdout] (T0, T1, T2, T3) [INFO] [stdout] (T0, T1, T2, T3, T4) [INFO] [stdout] and 127 others [INFO] [stdout] note: required by a bound in `serde_json::from_str` [INFO] [stdout] --> /opt/rustwide/cargo-home/registry/src/index.crates.io-6f17d22bba15001f/serde_json-1.0.96/src/de.rs:2603:8 [INFO] [stdout] | [INFO] [stdout] 2601 | pub fn from_str<'a, T>(s: &'a str) -> Result [INFO] [stdout] | -------- required by a bound in this function [INFO] [stdout] 2602 | where [INFO] [stdout] 2603 | T: de::Deserialize<'a>, [INFO] [stdout] | ^^^^^^^^^^^^^^^^^^^ required by this bound in `from_str` [INFO] [stdout] help: consider specifying the generic argument [INFO] [stdout] | [INFO] [stdout] 294 | let data = serde_json::from_str::(&raw_json); [INFO] [stdout] | +++++ [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] error[E0283]: type annotations needed [INFO] [stdout] --> src/main.rs:294:36 [INFO] [stdout] | [INFO] [stdout] 294 | let data = serde_json::from_str(&raw_json); [INFO] [stdout] | ^^^^^^^^^^^^^^^^^^^^ cannot infer type of the type parameter `T` declared on the function `from_str` [INFO] [stdout] | [INFO] [stdout] = note: cannot satisfy `_: serde::de::Deserialize<'_>` [INFO] [stdout] = help: the following types implement trait `serde::de::Deserialize<'de>`: [INFO] [stdout] &'a Path [INFO] [stdout] &'a [u8] [INFO] [stdout] &'a str [INFO] [stdout] () [INFO] [stdout] (T0, T1) [INFO] [stdout] (T0, T1, T2) [INFO] [stdout] (T0, T1, T2, T3) [INFO] [stdout] (T0, T1, T2, T3, T4) [INFO] [stdout] and 127 others [INFO] [stdout] note: required by a bound in `serde_json::from_str` [INFO] [stdout] --> /opt/rustwide/cargo-home/registry/src/index.crates.io-6f17d22bba15001f/serde_json-1.0.96/src/de.rs:2603:8 [INFO] [stdout] | [INFO] [stdout] 2601 | pub fn from_str<'a, T>(s: &'a str) -> Result [INFO] [stdout] | -------- required by a bound in this function [INFO] [stdout] 2602 | where [INFO] [stdout] 2603 | T: de::Deserialize<'a>, [INFO] [stdout] | ^^^^^^^^^^^^^^^^^^^ required by this bound in `from_str` [INFO] [stdout] help: consider specifying the generic argument [INFO] [stdout] | [INFO] [stdout] 294 | let data = serde_json::from_str::(&raw_json); [INFO] [stdout] | +++++ [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: unused variable: `player` [INFO] [stdout] --> src/main.rs:319:30 [INFO] [stdout] | [INFO] [stdout] 319 | fn start_dialogue(&self, player: &mut Player, in_dialogue: &mut bool) [INFO] [stdout] | ^^^^^^ help: if this is intentional, prefix it with an underscore: `_player` [INFO] [stdout] | [INFO] [stdout] = note: `#[warn(unused_variables)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: unused variable: `player` [INFO] [stdout] --> src/main.rs:319:30 [INFO] [stdout] | [INFO] [stdout] 319 | fn start_dialogue(&self, player: &mut Player, in_dialogue: &mut bool) [INFO] [stdout] | ^^^^^^ help: if this is intentional, prefix it with an underscore: `_player` [INFO] [stdout] | [INFO] [stdout] = note: `#[warn(unused_variables)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] error: aborting due to 1 previous error; 4 warnings emitted [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] For more information about this error, try `rustc --explain E0283`. [INFO] [stdout] [INFO] [stdout] error: aborting due to 1 previous error; 4 warnings emitted [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] For more information about this error, try `rustc --explain E0283`. [INFO] [stdout] [INFO] [stderr] error: could not compile `barney_defense` (bin "barney_defense" test) due to 2 previous errors; 4 warnings emitted [INFO] [stderr] warning: build failed, waiting for other jobs to finish... [INFO] [stderr] error: could not compile `barney_defense` (bin "barney_defense") due to 2 previous errors; 4 warnings emitted [INFO] running `Command { std: "docker" "inspect" "c196a70d2bc7ca81a75c7c053d6f028791cb365525c97298615b1e7a24d073e5", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "c196a70d2bc7ca81a75c7c053d6f028791cb365525c97298615b1e7a24d073e5", kill_on_drop: false }` [INFO] [stdout] c196a70d2bc7ca81a75c7c053d6f028791cb365525c97298615b1e7a24d073e5 [INFO] checking KasperG21/top_down_defense_game against try#707d6562f55b55a7aab4ab3a904997116b358314 for pr-122470 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKasperG21%2Ftop_down_defense_game" "/workspace/builds/worker-5-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/KasperG21/top_down_defense_game on toolchain 707d6562f55b55a7aab4ab3a904997116b358314 [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+707d6562f55b55a7aab4ab3a904997116b358314" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/KasperG21/top_down_defense_game [INFO] finished tweaking git repo https://github.com/KasperG21/top_down_defense_game [INFO] tweaked toml for git repo https://github.com/KasperG21/top_down_defense_game written to /workspace/builds/worker-5-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/KasperG21/top_down_defense_game 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" "+707d6562f55b55a7aab4ab3a904997116b358314" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] Blocking waiting for file lock on package cache [ERROR] error running command: no output for 300 seconds [INFO] checking KasperG21/top_down_defense_game against try#707d6562f55b55a7aab4ab3a904997116b358314 for pr-122470 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKasperG21%2Ftop_down_defense_game" "/workspace/builds/worker-5-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/KasperG21/top_down_defense_game on toolchain 707d6562f55b55a7aab4ab3a904997116b358314 [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+707d6562f55b55a7aab4ab3a904997116b358314" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/KasperG21/top_down_defense_game [INFO] finished tweaking git repo https://github.com/KasperG21/top_down_defense_game [INFO] tweaked toml for git repo https://github.com/KasperG21/top_down_defense_game written to /workspace/builds/worker-5-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/KasperG21/top_down_defense_game 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" "+707d6562f55b55a7aab4ab3a904997116b358314" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] Blocking waiting for file lock on package cache [INFO] [stderr] Blocking waiting for file lock on package cache [ERROR] error running command: no output for 300 seconds [INFO] checking KasperG21/top_down_defense_game against try#707d6562f55b55a7aab4ab3a904997116b358314 for pr-122470 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKasperG21%2Ftop_down_defense_game" "/workspace/builds/worker-5-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/KasperG21/top_down_defense_game on toolchain 707d6562f55b55a7aab4ab3a904997116b358314 [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+707d6562f55b55a7aab4ab3a904997116b358314" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/KasperG21/top_down_defense_game [INFO] finished tweaking git repo https://github.com/KasperG21/top_down_defense_game [INFO] tweaked toml for git repo https://github.com/KasperG21/top_down_defense_game written to /workspace/builds/worker-5-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/KasperG21/top_down_defense_game 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" "+707d6562f55b55a7aab4ab3a904997116b358314" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] Blocking waiting for file lock on package cache [INFO] [stderr] Blocking waiting for file lock on package cache [ERROR] error running command: no output for 300 seconds [INFO] checking KasperG21/top_down_defense_game against try#707d6562f55b55a7aab4ab3a904997116b358314 for pr-122470 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKasperG21%2Ftop_down_defense_game" "/workspace/builds/worker-5-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/KasperG21/top_down_defense_game on toolchain 707d6562f55b55a7aab4ab3a904997116b358314 [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+707d6562f55b55a7aab4ab3a904997116b358314" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/KasperG21/top_down_defense_game [INFO] finished tweaking git repo https://github.com/KasperG21/top_down_defense_game [INFO] tweaked toml for git repo https://github.com/KasperG21/top_down_defense_game written to /workspace/builds/worker-5-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/KasperG21/top_down_defense_game 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" "+707d6562f55b55a7aab4ab3a904997116b358314" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] Blocking waiting for file lock on package cache [INFO] [stderr] Blocking waiting for file lock on package cache [ERROR] error running command: no output for 300 seconds [INFO] checking KasperG21/top_down_defense_game against try#707d6562f55b55a7aab4ab3a904997116b358314 for pr-122470 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FKasperG21%2Ftop_down_defense_game" "/workspace/builds/worker-5-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/KasperG21/top_down_defense_game on toolchain 707d6562f55b55a7aab4ab3a904997116b358314 [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+707d6562f55b55a7aab4ab3a904997116b358314" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/KasperG21/top_down_defense_game [INFO] finished tweaking git repo https://github.com/KasperG21/top_down_defense_game [INFO] tweaked toml for git repo https://github.com/KasperG21/top_down_defense_game written to /workspace/builds/worker-5-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/KasperG21/top_down_defense_game 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" "+707d6562f55b55a7aab4ab3a904997116b358314" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] Blocking waiting for file lock on package cache [INFO] [stderr] Blocking waiting for file lock on package cache [ERROR] error running command: no output for 300 seconds [ERROR] this task or one of its parent failed! [ERROR] no output for 300 seconds [ERROR] note: run with `RUST_BACKTRACE=1` to display a backtrace.