[INFO] cloning repository https://github.com/cohama/pfds
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/cohama/pfds" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcohama%2Fpfds", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcohama%2Fpfds'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a81905a7f9b100c348aae02ad954f2a932e25f3d
[INFO] checking cohama/pfds against master#d97bb195bf7b84815622b235cb51171c1b8f7e51 for pr-117905
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcohama%2Fpfds" "/workspace/builds/worker-6-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/cohama/pfds on toolchain d97bb195bf7b84815622b235cb51171c1b8f7e51
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+d97bb195bf7b84815622b235cb51171c1b8f7e51" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/cohama/pfds
[INFO] finished tweaking git repo https://github.com/cohama/pfds
[INFO] tweaked toml for git repo https://github.com/cohama/pfds written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/cohama/pfds 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" "+d97bb195bf7b84815622b235cb51171c1b8f7e51" "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
[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.
[INFO] checking cohama/pfds against try#1930f260edd7e614aa013a0665aa5cfd0ada0501 for pr-117905
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcohama%2Fpfds" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/cohama/pfds on toolchain 1930f260edd7e614aa013a0665aa5cfd0ada0501
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1930f260edd7e614aa013a0665aa5cfd0ada0501" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/cohama/pfds
[INFO] finished tweaking git repo https://github.com/cohama/pfds
[INFO] tweaked toml for git repo https://github.com/cohama/pfds written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/cohama/pfds 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" "+1930f260edd7e614aa013a0665aa5cfd0ada0501" "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 cohama/pfds against try#1930f260edd7e614aa013a0665aa5cfd0ada0501 for pr-117905
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcohama%2Fpfds" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/cohama/pfds on toolchain 1930f260edd7e614aa013a0665aa5cfd0ada0501
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1930f260edd7e614aa013a0665aa5cfd0ada0501" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/cohama/pfds
[INFO] finished tweaking git repo https://github.com/cohama/pfds
[INFO] tweaked toml for git repo https://github.com/cohama/pfds written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/cohama/pfds 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" "+1930f260edd7e614aa013a0665aa5cfd0ada0501" "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] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded num-complex v0.1.40
[INFO] [stderr]   Downloaded num-rational v0.1.39
[INFO] [stderr]   Downloaded num-bigint v0.1.40
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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" "+1930f260edd7e614aa013a0665aa5cfd0ada0501" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f35d9118e7f0a4e36bd8fcbc8d1a55788e14c72690b2d393b068967a5f720de8
[INFO] running `Command { std: "docker" "start" "-a" "f35d9118e7f0a4e36bd8fcbc8d1a55788e14c72690b2d393b068967a5f720de8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f35d9118e7f0a4e36bd8fcbc8d1a55788e14c72690b2d393b068967a5f720de8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f35d9118e7f0a4e36bd8fcbc8d1a55788e14c72690b2d393b068967a5f720de8", kill_on_drop: false }`
[INFO] [stdout] f35d9118e7f0a4e36bd8fcbc8d1a55788e14c72690b2d393b068967a5f720de8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1930f260edd7e614aa013a0665aa5cfd0ada0501" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f63a250d20c2eee65657c0744fbfd2b832a0b131855f5e31033671e36a83ece0
[INFO] running `Command { std: "docker" "start" "-a" "f63a250d20c2eee65657c0744fbfd2b832a0b131855f5e31033671e36a83ece0", kill_on_drop: false }`
[INFO] [stderr]     Checking num-traits v0.1.40
[INFO] [stderr]     Checking libc v0.2.29
[INFO] [stderr]     Checking rand v0.3.16
[INFO] [stderr]     Checking num-integer v0.1.35
[INFO] [stderr]     Checking num-complex v0.1.40
[INFO] [stderr]     Checking num-iter v0.1.34
[INFO] [stderr]     Checking num-bigint v0.1.40
[INFO] [stderr]     Checking num-rational v0.1.39
[INFO] [stderr]     Checking num v0.1.40
[INFO] [stderr]     Checking stopwatch v0.0.7
[INFO] [stderr]     Checking pfds v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> src/lib.rs:4:12
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(box_syntax)]
[INFO] [stdout]   |            ^^^^^^^^^^ feature has been removed
[INFO] [stdout]   |
[INFO] [stdout]   = note: replaced with `#[rustc_box]`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> src/lib.rs:4:12
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(box_syntax)]
[INFO] [stdout]   |            ^^^^^^^^^^ feature has been removed
[INFO] [stdout]   |
[INFO] [stdout]   = note: replaced with `#[rustc_box]`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:231:68
[INFO] [stdout]     |
[INFO] [stdout] 231 |   ...                   trampoline(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout]     |  __________________________________________________________^
[INFO] [stdout] 232 | | ...                       k(Node(Black,
[INFO] [stdout] 233 | | ...                              Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] 234 | | ...                              x,
[INFO] [stdout] 235 | | ...                              Rc::new(rtree.clone())
[INFO] [stdout] 236 | | ...                       ), rcount + 1, rest)
[INFO] [stdout] 237 | | ...                   })
[INFO] [stdout]     | |_______________________^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 231 ~                                 trampoline(xs.clone(), n - n/2 -1, Box::new(move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 232 +                                     k(Node(Black,
[INFO] [stdout] 233 +                                            Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] 234 +                                            x,
[INFO] [stdout] 235 +                                            Rc::new(rtree.clone())
[INFO] [stdout] 236 +                                     ), rcount + 1, rest)
[INFO] [stdout] 237 ~                                 }))
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:231:68
[INFO] [stdout]     |
[INFO] [stdout] 231 |   ...                   trampoline(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout]     |  __________________________________________________________^
[INFO] [stdout] 232 | | ...                       k(Node(Black,
[INFO] [stdout] 233 | | ...                              Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] 234 | | ...                              x,
[INFO] [stdout] 235 | | ...                              Rc::new(rtree.clone())
[INFO] [stdout] 236 | | ...                       ), rcount + 1, rest)
[INFO] [stdout] 237 | | ...                   })
[INFO] [stdout]     | |_______________________^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 231 ~                                 trampoline(xs.clone(), n - n/2 -1, Box::new(move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 232 +                                     k(Node(Black,
[INFO] [stdout] 233 +                                            Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] 234 +                                            x,
[INFO] [stdout] 235 +                                            Rc::new(rtree.clone())
[INFO] [stdout] 236 +                                     ), rcount + 1, rest)
[INFO] [stdout] 237 ~                                 }))
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:230:43
[INFO] [stdout]     |
[INFO] [stdout] 230 |   ...                   TailRec::Func(box move || {
[INFO] [stdout]     |  _____________________________________^
[INFO] [stdout] 231 | | ...                       trampoline(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 232 | | ...                           k(Node(Black,
[INFO] [stdout] 233 | | ...                                  Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] ...   |
[INFO] [stdout] 237 | | ...                       })
[INFO] [stdout] 238 | | ...                   })
[INFO] [stdout]     | |_______________________^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 230 ~                             TailRec::Func(Box::new(move || {
[INFO] [stdout] 231 +                                 trampoline(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 232 +                                     k(Node(Black,
[INFO] [stdout] 233 +                                            Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] 234 +                                            x,
[INFO] [stdout] 235 +                                            Rc::new(rtree.clone())
[INFO] [stdout] 236 +                                     ), rcount + 1, rest)
[INFO] [stdout] 237 +                                 })
[INFO] [stdout] 238 ~                             }))
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:230:43
[INFO] [stdout]     |
[INFO] [stdout] 230 |   ...                   TailRec::Func(box move || {
[INFO] [stdout]     |  _____________________________________^
[INFO] [stdout] 231 | | ...                       trampoline(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 232 | | ...                           k(Node(Black,
[INFO] [stdout] 233 | | ...                                  Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] ...   |
[INFO] [stdout] 237 | | ...                       })
[INFO] [stdout] 238 | | ...                   })
[INFO] [stdout]     | |_______________________^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 230 ~                             TailRec::Func(Box::new(move || {
[INFO] [stdout] 231 +                                 trampoline(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 232 +                                     k(Node(Black,
[INFO] [stdout] 233 +                                            Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] 234 +                                            x,
[INFO] [stdout] 235 +                                            Rc::new(rtree.clone())
[INFO] [stdout] 236 +                                     ), rcount + 1, rest)
[INFO] [stdout] 237 +                                 })
[INFO] [stdout] 238 ~                             }))
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:228:45
[INFO] [stdout]     |
[INFO] [stdout] 228 |                           trampoline(xs, n/2, box move |ltree: RedBlackTree<T>, lcount: i32, rest: List<T>| {
[INFO] [stdout]     |  _____________________________________________^
[INFO] [stdout] 229 | |                             let (x, xs) = rest.to_cons();
[INFO] [stdout] 230 | |                             TailRec::Func(box move || {
[INFO] [stdout] 231 | |                                 trampoline(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] ...   |
[INFO] [stdout] 238 | |                             })
[INFO] [stdout] 239 | |                         })
[INFO] [stdout]     | |_________________________^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 228 ~                         trampoline(xs, n/2, Box::new(move |ltree: RedBlackTree<T>, lcount: i32, rest: List<T>| {
[INFO] [stdout] 229 +                             let (x, xs) = rest.to_cons();
[INFO] [stdout] 230 +                             TailRec::Func(box move || {
[INFO] [stdout] 231 +                                 trampoline(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 232 +                                     k(Node(Black,
[INFO] [stdout] 233 +                                            Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] 234 +                                            x,
[INFO] [stdout] 235 +                                            Rc::new(rtree.clone())
[INFO] [stdout] 236 +                                     ), rcount + 1, rest)
[INFO] [stdout] 237 +                                 })
[INFO] [stdout] 238 +                             })
[INFO] [stdout] 239 ~                         }))
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:228:45
[INFO] [stdout]     |
[INFO] [stdout] 228 |                           trampoline(xs, n/2, box move |ltree: RedBlackTree<T>, lcount: i32, rest: List<T>| {
[INFO] [stdout]     |  _____________________________________________^
[INFO] [stdout] 229 | |                             let (x, xs) = rest.to_cons();
[INFO] [stdout] 230 | |                             TailRec::Func(box move || {
[INFO] [stdout] 231 | |                                 trampoline(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] ...   |
[INFO] [stdout] 238 | |                             })
[INFO] [stdout] 239 | |                         })
[INFO] [stdout]     | |_________________________^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 228 ~                         trampoline(xs, n/2, Box::new(move |ltree: RedBlackTree<T>, lcount: i32, rest: List<T>| {
[INFO] [stdout] 229 +                             let (x, xs) = rest.to_cons();
[INFO] [stdout] 230 +                             TailRec::Func(box move || {
[INFO] [stdout] 231 +                                 trampoline(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 232 +                                     k(Node(Black,
[INFO] [stdout] 233 +                                            Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] 234 +                                            x,
[INFO] [stdout] 235 +                                            Rc::new(rtree.clone())
[INFO] [stdout] 236 +                                     ), rcount + 1, rest)
[INFO] [stdout] 237 +                                 })
[INFO] [stdout] 238 +                             })
[INFO] [stdout] 239 ~                         }))
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:227:35
[INFO] [stdout]     |
[INFO] [stdout] 227 |                       TailRec::Func(box move || {
[INFO] [stdout]     |  ___________________________________^
[INFO] [stdout] 228 | |                         trampoline(xs, n/2, box move |ltree: RedBlackTree<T>, lcount: i32, rest: List<T>| {
[INFO] [stdout] 229 | |                             let (x, xs) = rest.to_cons();
[INFO] [stdout] 230 | |                             TailRec::Func(box move || {
[INFO] [stdout] ...   |
[INFO] [stdout] 239 | |                         })
[INFO] [stdout] 240 | |                     })
[INFO] [stdout]     | |_____________________^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 227 ~                     TailRec::Func(Box::new(move || {
[INFO] [stdout] 228 +                         trampoline(xs, n/2, box move |ltree: RedBlackTree<T>, lcount: i32, rest: List<T>| {
[INFO] [stdout] 229 +                             let (x, xs) = rest.to_cons();
[INFO] [stdout] 230 +                             TailRec::Func(box move || {
[INFO] [stdout] 231 +                                 trampoline(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 232 +                                     k(Node(Black,
[INFO] [stdout] 233 +                                            Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] 234 +                                            x,
[INFO] [stdout] 235 +                                            Rc::new(rtree.clone())
[INFO] [stdout] 236 +                                     ), rcount + 1, rest)
[INFO] [stdout] 237 +                                 })
[INFO] [stdout] 238 +                             })
[INFO] [stdout] 239 +                         })
[INFO] [stdout] 240 ~                     }))
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:245:27
[INFO] [stdout]     |
[INFO] [stdout] 245 |         trampoline(xs, n, box |t, _, _| TailRec::Val(t)).run()
[INFO] [stdout]     |                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 245 |         trampoline(xs, n, Box::new(|t, _, _| TailRec::Val(t))).run()
[INFO] [stdout]     |                           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:227:35
[INFO] [stdout]     |
[INFO] [stdout] 227 |                       TailRec::Func(box move || {
[INFO] [stdout]     |  ___________________________________^
[INFO] [stdout] 228 | |                         trampoline(xs, n/2, box move |ltree: RedBlackTree<T>, lcount: i32, rest: List<T>| {
[INFO] [stdout] 229 | |                             let (x, xs) = rest.to_cons();
[INFO] [stdout] 230 | |                             TailRec::Func(box move || {
[INFO] [stdout] ...   |
[INFO] [stdout] 239 | |                         })
[INFO] [stdout] 240 | |                     })
[INFO] [stdout]     | |_____________________^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 227 ~                     TailRec::Func(Box::new(move || {
[INFO] [stdout] 228 +                         trampoline(xs, n/2, box move |ltree: RedBlackTree<T>, lcount: i32, rest: List<T>| {
[INFO] [stdout] 229 +                             let (x, xs) = rest.to_cons();
[INFO] [stdout] 230 +                             TailRec::Func(box move || {
[INFO] [stdout] 231 +                                 trampoline(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 232 +                                     k(Node(Black,
[INFO] [stdout] 233 +                                            Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] 234 +                                            x,
[INFO] [stdout] 235 +                                            Rc::new(rtree.clone())
[INFO] [stdout] 236 +                                     ), rcount + 1, rest)
[INFO] [stdout] 237 +                                 })
[INFO] [stdout] 238 +                             })
[INFO] [stdout] 239 +                         })
[INFO] [stdout] 240 ~                     }))
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:245:27
[INFO] [stdout]     |
[INFO] [stdout] 245 |         trampoline(xs, n, box |t, _, _| TailRec::Val(t)).run()
[INFO] [stdout]     |                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 245 |         trampoline(xs, n, Box::new(|t, _, _| TailRec::Val(t))).run()
[INFO] [stdout]     |                           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:264:58
[INFO] [stdout]     |
[INFO] [stdout] 264 |                           walk_cps(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout]     |  __________________________________________________________^
[INFO] [stdout] 265 | |                             k(Node(
[INFO] [stdout] 266 | |                                 Black,
[INFO] [stdout] 267 | |                                 Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] ...   |
[INFO] [stdout] 270 | |                             ), rcount + 1, rest)
[INFO] [stdout] 271 | |                         })
[INFO] [stdout]     | |_________________________^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 264 ~                         walk_cps(xs.clone(), n - n/2 -1, Box::new(move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 265 +                             k(Node(
[INFO] [stdout] 266 +                                 Black,
[INFO] [stdout] 267 +                                 Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] 268 +                                 x.clone(),
[INFO] [stdout] 269 +                                 Rc::new(rtree.clone())
[INFO] [stdout] 270 +                             ), rcount + 1, rest)
[INFO] [stdout] 271 ~                         }))
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:264:58
[INFO] [stdout]     |
[INFO] [stdout] 264 |                           walk_cps(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout]     |  __________________________________________________________^
[INFO] [stdout] 265 | |                             k(Node(
[INFO] [stdout] 266 | |                                 Black,
[INFO] [stdout] 267 | |                                 Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] ...   |
[INFO] [stdout] 270 | |                             ), rcount + 1, rest)
[INFO] [stdout] 271 | |                         })
[INFO] [stdout]     | |_________________________^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 264 ~                         walk_cps(xs.clone(), n - n/2 -1, Box::new(move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 265 +                             k(Node(
[INFO] [stdout] 266 +                                 Black,
[INFO] [stdout] 267 +                                 Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] 268 +                                 x.clone(),
[INFO] [stdout] 269 +                                 Rc::new(rtree.clone())
[INFO] [stdout] 270 +                             ), rcount + 1, rest)
[INFO] [stdout] 271 ~                         }))
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:262:39
[INFO] [stdout]     |
[INFO] [stdout] 262 |                       walk_cps(xs, n/2, box move |ltree: RedBlackTree<T>, lcount: i32, rest: List<T>| {
[INFO] [stdout]     |  _______________________________________^
[INFO] [stdout] 263 | |                         let (x, xs) = rest.decom();
[INFO] [stdout] 264 | |                         walk_cps(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 265 | |                             k(Node(
[INFO] [stdout] ...   |
[INFO] [stdout] 271 | |                         })
[INFO] [stdout] 272 | |                     })
[INFO] [stdout]     | |_____________________^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 262 ~                     walk_cps(xs, n/2, Box::new(move |ltree: RedBlackTree<T>, lcount: i32, rest: List<T>| {
[INFO] [stdout] 263 +                         let (x, xs) = rest.decom();
[INFO] [stdout] 264 +                         walk_cps(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 265 +                             k(Node(
[INFO] [stdout] 266 +                                 Black,
[INFO] [stdout] 267 +                                 Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] 268 +                                 x.clone(),
[INFO] [stdout] 269 +                                 Rc::new(rtree.clone())
[INFO] [stdout] 270 +                             ), rcount + 1, rest)
[INFO] [stdout] 271 +                         })
[INFO] [stdout] 272 ~                     }))
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:277:25
[INFO] [stdout]     |
[INFO] [stdout] 277 |         walk_cps(xs, n, box |t, _, _| t)
[INFO] [stdout]     |                         ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 277 |         walk_cps(xs, n, Box::new(|t, _, _| t))
[INFO] [stdout]     |                         ~~~~~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:262:39
[INFO] [stdout]     |
[INFO] [stdout] 262 |                       walk_cps(xs, n/2, box move |ltree: RedBlackTree<T>, lcount: i32, rest: List<T>| {
[INFO] [stdout]     |  _______________________________________^
[INFO] [stdout] 263 | |                         let (x, xs) = rest.decom();
[INFO] [stdout] 264 | |                         walk_cps(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 265 | |                             k(Node(
[INFO] [stdout] ...   |
[INFO] [stdout] 271 | |                         })
[INFO] [stdout] 272 | |                     })
[INFO] [stdout]     | |_____________________^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 262 ~                     walk_cps(xs, n/2, Box::new(move |ltree: RedBlackTree<T>, lcount: i32, rest: List<T>| {
[INFO] [stdout] 263 +                         let (x, xs) = rest.decom();
[INFO] [stdout] 264 +                         walk_cps(xs.clone(), n - n/2 -1, box move |rtree: RedBlackTree<T>, rcount: i32, rest: List<T>| {
[INFO] [stdout] 265 +                             k(Node(
[INFO] [stdout] 266 +                                 Black,
[INFO] [stdout] 267 +                                 Rc::new(if lcount > rcount {ltree.set_root_color(Red)} else {ltree.clone()}),
[INFO] [stdout] 268 +                                 x.clone(),
[INFO] [stdout] 269 +                                 Rc::new(rtree.clone())
[INFO] [stdout] 270 +                             ), rcount + 1, rest)
[INFO] [stdout] 271 +                         })
[INFO] [stdout] 272 ~                     }))
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/impls/redblacktree.rs:277:25
[INFO] [stdout]     |
[INFO] [stdout] 277 |         walk_cps(xs, n, box |t, _, _| t)
[INFO] [stdout]     |                         ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 277 |         walk_cps(xs, n, Box::new(|t, _, _| t))
[INFO] [stdout]     |                         ~~~~~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0432]: unresolved import `std::boxed::FnBox`
[INFO] [stdout]  --> src/impls/redblacktree.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::boxed::FnBox;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^ no `FnBox` in `boxed`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0432]: unresolved import `std::boxed::FnBox`
[INFO] [stdout]  --> src/impls/redblacktree.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::boxed::FnBox;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^ no `FnBox` in `boxed`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]   --> src/impls/binominalheap2.rs:46:21
[INFO] [stdout]    |
[INFO] [stdout] 46 | pub type BHeap<T> = (List<(i32, BinominalTree<T>)>);
[INFO] [stdout]    |                     ^                             ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout] 46 - pub type BHeap<T> = (List<(i32, BinominalTree<T>)>);
[INFO] [stdout] 46 + pub type BHeap<T> = List<(i32, BinominalTree<T>)>;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]   --> src/impls/binominalheap2.rs:46:21
[INFO] [stdout]    |
[INFO] [stdout] 46 | pub type BHeap<T> = (List<(i32, BinominalTree<T>)>);
[INFO] [stdout]    |                     ^                             ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout] 46 - pub type BHeap<T> = (List<(i32, BinominalTree<T>)>);
[INFO] [stdout] 46 + pub type BHeap<T> = List<(i32, BinominalTree<T>)>;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0635]: unknown feature `fnbox`
[INFO] [stdout]  --> src/lib.rs:3:12
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(fnbox)]
[INFO] [stdout]   |            ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/impls/redblacktree.rs:39:14
[INFO] [stdout]    |
[INFO] [stdout] 39 |     Func(Box<FnBox() -> TailRec<'a, T> + 'a>)
[INFO] [stdout]    |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 39 |     Func(Box<dyn FnBox() -> TailRec<'a, T> + 'a>)
[INFO] [stdout]    |              +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0635]: unknown feature `fnbox`
[INFO] [stdout]  --> src/lib.rs:3:12
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(fnbox)]
[INFO] [stdout]   |            ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/impls/redblacktree.rs:39:14
[INFO] [stdout]    |
[INFO] [stdout] 39 |     Func(Box<FnBox() -> TailRec<'a, T> + 'a>)
[INFO] [stdout]    |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 39 |     Func(Box<dyn FnBox() -> TailRec<'a, T> + 'a>)
[INFO] [stdout]    |              +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 11 previous errors; 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0432, E0557, E0635.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0432`.
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 11 previous errors; 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0432, E0557, E0635.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0432`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `pfds` (lib) due to 12 previous errors; 2 warnings emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: could not compile `pfds` (lib test) due to 12 previous errors; 2 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "f63a250d20c2eee65657c0744fbfd2b832a0b131855f5e31033671e36a83ece0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f63a250d20c2eee65657c0744fbfd2b832a0b131855f5e31033671e36a83ece0", kill_on_drop: false }`
[INFO] [stdout] f63a250d20c2eee65657c0744fbfd2b832a0b131855f5e31033671e36a83ece0