[INFO] cloning repository https://github.com/sergi-ko/sandbox-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/sergi-ko/sandbox-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsergi-ko%2Fsandbox-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsergi-ko%2Fsandbox-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a570dac2679a729ee28482b6eefdfe5b7b2b8db9
[INFO] testing sergi-ko/sandbox-rust against master#b70888601af92f6cdc0364abab3446e418b91d36 for pr-86479
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsergi-ko%2Fsandbox-rust" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/sergi-ko/sandbox-rust on toolchain b70888601af92f6cdc0364abab3446e418b91d36
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b70888601af92f6cdc0364abab3446e418b91d36" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/sergi-ko/sandbox-rust
[INFO] finished tweaking git repo https://github.com/sergi-ko/sandbox-rust
[INFO] tweaked toml for git repo https://github.com/sergi-ko/sandbox-rust written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/sergi-ko/sandbox-rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b70888601af92f6cdc0364abab3446e418b91d36" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+b70888601af92f6cdc0364abab3446e418b91d36" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4dd37737dc34908dc491d1bf27ae8e6e78728267102c342c2c1fbf9f917edd94
[INFO] running `Command { std: "docker" "start" "-a" "4dd37737dc34908dc491d1bf27ae8e6e78728267102c342c2c1fbf9f917edd94", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4dd37737dc34908dc491d1bf27ae8e6e78728267102c342c2c1fbf9f917edd94", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4dd37737dc34908dc491d1bf27ae8e6e78728267102c342c2c1fbf9f917edd94", kill_on_drop: false }`
[INFO] [stdout] 4dd37737dc34908dc491d1bf27ae8e6e78728267102c342c2c1fbf9f917edd94
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+b70888601af92f6cdc0364abab3446e418b91d36" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 79ab4339f8af69512eab7dc17c2d05164e9c75719ab1fa05d0d409236cdbd812
[INFO] running `Command { std: "docker" "start" "-a" "79ab4339f8af69512eab7dc17c2d05164e9c75719ab1fa05d0d409236cdbd812", kill_on_drop: false }`
[INFO] [stderr]    Compiling sandbox-rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::cmp::Ordering`
[INFO] [stdout]  --> src/enums.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::cmp::Ordering;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::ops::Deref`
[INFO] [stdout]  --> src/refcounts.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::ops::Deref;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `crate::iter::test_performance`
[INFO] [stdout]  --> src/main.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 | use crate::iter::test_performance;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `crate::refcounts::do_refcount`
[INFO] [stdout]   --> src/main.rs:15:5
[INFO] [stdout]    |
[INFO] [stdout] 15 | use crate::refcounts::do_refcount;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `crate::enums::enum_and_map`
[INFO] [stdout]   --> src/main.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 17 | use crate::enums::enum_and_map;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `crate::binary_heap::test_binary_heap`
[INFO] [stdout]   --> src/main.rs:19:5
[INFO] [stdout]    |
[INFO] [stdout] 19 | use crate::binary_heap::test_binary_heap;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `val`
[INFO] [stdout]   --> src/refcounts.rs:29:26
[INFO] [stdout]    |
[INFO] [stdout] 29 |             MyTree::Leaf(val, l, r) => *l = Rc::new(leaf),
[INFO] [stdout]    |                          ^^^ help: if this is intentional, prefix it with an underscore: `_val`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r`
[INFO] [stdout]   --> src/refcounts.rs:29:34
[INFO] [stdout]    |
[INFO] [stdout] 29 |             MyTree::Leaf(val, l, r) => *l = Rc::new(leaf),
[INFO] [stdout]    |                                  ^ help: if this is intentional, prefix it with an underscore: `_r`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `leaf`
[INFO] [stdout]   --> src/refcounts.rs:33:29
[INFO] [stdout]    |
[INFO] [stdout] 33 |     fn add_right(&mut self, leaf: MyTree) {}
[INFO] [stdout]    |                             ^^^^ help: if this is intentional, prefix it with an underscore: `_leaf`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `add_left`
[INFO] [stdout]   --> src/refcounts.rs:27:8
[INFO] [stdout]    |
[INFO] [stdout] 27 |     fn add_left(&mut self, leaf: MyTree) {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `add_right`
[INFO] [stdout]   --> src/refcounts.rs:33:8
[INFO] [stdout]    |
[INFO] [stdout] 33 |     fn add_right(&mut self, leaf: MyTree) {}
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]   --> src/iter.rs:85:26
[INFO] [stdout]    |
[INFO] [stdout] 85 |         Err(e) => panic!(e),
[INFO] [stdout]    |                          ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_fmt_panics)]` on by default
[INFO] [stdout]    = note: this usage of panic!() is deprecated; it will be a hard error in Rust 2021
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[INFO] [stdout] help: add a "{}" format string to Display the message
[INFO] [stdout]    |
[INFO] [stdout] 85 |         Err(e) => panic!("{}", e),
[INFO] [stdout]    |                          ^^^^^
[INFO] [stdout] help: or use std::panic::panic_any instead
[INFO] [stdout]    |
[INFO] [stdout] 85 |         Err(e) => std::panic::panic_any(e),
[INFO] [stdout]    |                   ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 12 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.63s
[INFO] running `Command { std: "docker" "inspect" "79ab4339f8af69512eab7dc17c2d05164e9c75719ab1fa05d0d409236cdbd812", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "79ab4339f8af69512eab7dc17c2d05164e9c75719ab1fa05d0d409236cdbd812", kill_on_drop: false }`
[INFO] [stdout] 79ab4339f8af69512eab7dc17c2d05164e9c75719ab1fa05d0d409236cdbd812
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+b70888601af92f6cdc0364abab3446e418b91d36" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3e31bef1cdc654fb6978391e9be9c32f2e44032b04908d10d0959f9a0fc9aebd
[INFO] running `Command { std: "docker" "start" "-a" "3e31bef1cdc654fb6978391e9be9c32f2e44032b04908d10d0959f9a0fc9aebd", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling sandbox-rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::cmp::Ordering`
[INFO] [stdout]  --> src/enums.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::cmp::Ordering;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::ops::Deref`
[INFO] [stdout]  --> src/refcounts.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::ops::Deref;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `crate::iter::test_performance`
[INFO] [stdout]  --> src/main.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 | use crate::iter::test_performance;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `crate::refcounts::do_refcount`
[INFO] [stdout]   --> src/main.rs:15:5
[INFO] [stdout]    |
[INFO] [stdout] 15 | use crate::refcounts::do_refcount;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `crate::enums::enum_and_map`
[INFO] [stdout]   --> src/main.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 17 | use crate::enums::enum_and_map;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `crate::binary_heap::test_binary_heap`
[INFO] [stdout]   --> src/main.rs:19:5
[INFO] [stdout]    |
[INFO] [stdout] 19 | use crate::binary_heap::test_binary_heap;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `val`
[INFO] [stdout]   --> src/refcounts.rs:29:26
[INFO] [stdout]    |
[INFO] [stdout] 29 |             MyTree::Leaf(val, l, r) => *l = Rc::new(leaf),
[INFO] [stdout]    |                          ^^^ help: if this is intentional, prefix it with an underscore: `_val`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `r`
[INFO] [stdout]   --> src/refcounts.rs:29:34
[INFO] [stdout]    |
[INFO] [stdout] 29 |             MyTree::Leaf(val, l, r) => *l = Rc::new(leaf),
[INFO] [stdout]    |                                  ^ help: if this is intentional, prefix it with an underscore: `_r`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `leaf`
[INFO] [stdout]   --> src/refcounts.rs:33:29
[INFO] [stdout]    |
[INFO] [stdout] 33 |     fn add_right(&mut self, leaf: MyTree) {}
[INFO] [stdout]    |                             ^^^^ help: if this is intentional, prefix it with an underscore: `_leaf`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `add_left`
[INFO] [stdout]   --> src/refcounts.rs:27:8
[INFO] [stdout]    |
[INFO] [stdout] 27 |     fn add_left(&mut self, leaf: MyTree) {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `add_right`
[INFO] [stdout]   --> src/refcounts.rs:33:8
[INFO] [stdout]    |
[INFO] [stdout] 33 |     fn add_right(&mut self, leaf: MyTree) {}
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]   --> src/iter.rs:85:26
[INFO] [stdout]    |
[INFO] [stdout] 85 |         Err(e) => panic!(e),
[INFO] [stdout]    |                          ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_fmt_panics)]` on by default
[INFO] [stdout]    = note: this usage of panic!() is deprecated; it will be a hard error in Rust 2021
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[INFO] [stdout] help: add a "{}" format string to Display the message
[INFO] [stdout]    |
[INFO] [stdout] 85 |         Err(e) => panic!("{}", e),
[INFO] [stdout]    |                          ^^^^^
[INFO] [stdout] help: or use std::panic::panic_any instead
[INFO] [stdout]    |
[INFO] [stdout] 85 |         Err(e) => std::panic::panic_any(e),
[INFO] [stdout]    |                   ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 12 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.66s
[INFO] running `Command { std: "docker" "inspect" "3e31bef1cdc654fb6978391e9be9c32f2e44032b04908d10d0959f9a0fc9aebd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3e31bef1cdc654fb6978391e9be9c32f2e44032b04908d10d0959f9a0fc9aebd", kill_on_drop: false }`
[INFO] [stdout] 3e31bef1cdc654fb6978391e9be9c32f2e44032b04908d10d0959f9a0fc9aebd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+b70888601af92f6cdc0364abab3446e418b91d36" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 0104fe4ffbe1c9b5d284de8e9584310cb87e2f9cf225b2c7007697be7b063dfc
[INFO] running `Command { std: "docker" "start" "-a" "0104fe4ffbe1c9b5d284de8e9584310cb87e2f9cf225b2c7007697be7b063dfc", kill_on_drop: false }`
[INFO] [stdout] 
[INFO] [stderr] warning: unused import: `std::cmp::Ordering`
[INFO] [stdout] running 0 tests
[INFO] [stderr]  --> src/enums.rs:1:5
[INFO] [stdout] 
[INFO] [stderr]   |
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stderr] 1 | use std::cmp::Ordering;
[INFO] [stdout] 
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::ops::Deref`
[INFO] [stderr]  --> src/refcounts.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::ops::Deref;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `crate::iter::test_performance`
[INFO] [stderr]  --> src/main.rs:9:5
[INFO] [stderr]   |
[INFO] [stderr] 9 | use crate::iter::test_performance;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `crate::refcounts::do_refcount`
[INFO] [stderr]   --> src/main.rs:15:5
[INFO] [stderr]    |
[INFO] [stderr] 15 | use crate::refcounts::do_refcount;
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `crate::enums::enum_and_map`
[INFO] [stderr]   --> src/main.rs:17:5
[INFO] [stderr]    |
[INFO] [stderr] 17 | use crate::enums::enum_and_map;
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `crate::binary_heap::test_binary_heap`
[INFO] [stderr]   --> src/main.rs:19:5
[INFO] [stderr]    |
[INFO] [stderr] 19 | use crate::binary_heap::test_binary_heap;
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `val`
[INFO] [stderr]   --> src/refcounts.rs:29:26
[INFO] [stderr]    |
[INFO] [stderr] 29 |             MyTree::Leaf(val, l, r) => *l = Rc::new(leaf),
[INFO] [stderr]    |                          ^^^ help: if this is intentional, prefix it with an underscore: `_val`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `r`
[INFO] [stderr]   --> src/refcounts.rs:29:34
[INFO] [stderr]    |
[INFO] [stderr] 29 |             MyTree::Leaf(val, l, r) => *l = Rc::new(leaf),
[INFO] [stderr]    |                                  ^ help: if this is intentional, prefix it with an underscore: `_r`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `leaf`
[INFO] [stderr]   --> src/refcounts.rs:33:29
[INFO] [stderr]    |
[INFO] [stderr] 33 |     fn add_right(&mut self, leaf: MyTree) {}
[INFO] [stderr]    |                             ^^^^ help: if this is intentional, prefix it with an underscore: `_leaf`
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `add_left`
[INFO] [stderr]   --> src/refcounts.rs:27:8
[INFO] [stderr]    |
[INFO] [stderr] 27 |     fn add_left(&mut self, leaf: MyTree) {
[INFO] [stderr]    |        ^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `add_right`
[INFO] [stderr]   --> src/refcounts.rs:33:8
[INFO] [stderr]    |
[INFO] [stderr] 33 |     fn add_right(&mut self, leaf: MyTree) {}
[INFO] [stderr]    |        ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: panic message is not a string literal
[INFO] [stderr]   --> src/iter.rs:85:26
[INFO] [stderr]    |
[INFO] [stderr] 85 |         Err(e) => panic!(e),
[INFO] [stderr]    |                          ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(non_fmt_panics)]` on by default
[INFO] [stderr]    = note: this usage of panic!() is deprecated; it will be a hard error in Rust 2021
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[INFO] [stderr] help: add a "{}" format string to Display the message
[INFO] [stderr]    |
[INFO] [stderr] 85 |         Err(e) => panic!("{}", e),
[INFO] [stderr]    |                          ^^^^^
[INFO] [stderr] help: or use std::panic::panic_any instead
[INFO] [stderr]    |
[INFO] [stderr] 85 |         Err(e) => std::panic::panic_any(e),
[INFO] [stderr]    |                   ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: `sandbox-rust` (bin "sandbox-rust" test) generated 12 warnings
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/sandbox_rust-5d86a492201228ce)
[INFO] running `Command { std: "docker" "inspect" "0104fe4ffbe1c9b5d284de8e9584310cb87e2f9cf225b2c7007697be7b063dfc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0104fe4ffbe1c9b5d284de8e9584310cb87e2f9cf225b2c7007697be7b063dfc", kill_on_drop: false }`
[INFO] [stdout] 0104fe4ffbe1c9b5d284de8e9584310cb87e2f9cf225b2c7007697be7b063dfc