[INFO] cloning repository https://github.com/FallibleVagrant/fvtree
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/FallibleVagrant/fvtree" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FFallibleVagrant%2Ffvtree", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FFallibleVagrant%2Ffvtree'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] c0d3803cb517e22d98eb1d41ffeb5767a97dcb11
[INFO] building FallibleVagrant/fvtree against master#11663cd3bfefef7d34e8f0892c250bf698049392+rustflags=-Dtail-expr-drop-order for pr-134523
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FFallibleVagrant%2Ffvtree" "/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/FallibleVagrant/fvtree on toolchain 11663cd3bfefef7d34e8f0892c250bf698049392
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/FallibleVagrant/fvtree
[INFO] finished tweaking git repo https://github.com/FallibleVagrant/fvtree
[INFO] tweaked toml for git repo https://github.com/FallibleVagrant/fvtree written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/FallibleVagrant/fvtree 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" "+11663cd3bfefef7d34e8f0892c250bf698049392" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2e41d52e9abc639ba87cba6c3eae55ff83fa106f740f04ba25973970ad9a9a87
[INFO] running `Command { std: "docker" "start" "-a" "2e41d52e9abc639ba87cba6c3eae55ff83fa106f740f04ba25973970ad9a9a87", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2e41d52e9abc639ba87cba6c3eae55ff83fa106f740f04ba25973970ad9a9a87", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2e41d52e9abc639ba87cba6c3eae55ff83fa106f740f04ba25973970ad9a9a87", kill_on_drop: false }`
[INFO] [stdout] 2e41d52e9abc639ba87cba6c3eae55ff83fa106f740f04ba25973970ad9a9a87
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 92e0befb029be9d804b93318894f8211c4622de04b660881c34433f1c7c0fc45
[INFO] running `Command { std: "docker" "start" "-a" "92e0befb029be9d804b93318894f8211c4622de04b660881c34433f1c7c0fc45", kill_on_drop: false }`
[INFO] [stderr]    Compiling common v0.1.0 (/opt/rustwide/workdir/common)
[INFO] [stderr]    Compiling text_canvas v0.1.0 (/opt/rustwide/workdir/text_canvas)
[INFO] [stderr]    Compiling fvtree v0.1.0 (/opt/rustwide/workdir/fvtree)
[INFO] [stdout] warning: unused import: `rand::Rng`
[INFO] [stdout]  --> fvtree/src/tree_gen_recursive.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use rand::Rng;
[INFO] [stdout]   |     ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `TreeStats`
[INFO] [stdout]  --> fvtree/src/tree_gen_recursive.rs:4:39
[INFO] [stdout]   |
[INFO] [stdout] 4 | use crate::confstats::{Stats, Config, TreeStats, BranchStats};
[INFO] [stdout]   |                                       ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: denote infinite loops with `loop { ... }`
[INFO] [stdout]    --> fvtree/src/tree_gen_recursive.rs:161:5
[INFO] [stdout]     |
[INFO] [stdout] 161 |     while true {
[INFO] [stdout]     |     ^^^^^^^^^^ help: use `loop`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(while_true)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `is_same_char` is never used
[INFO] [stdout]    --> fvtree/src/sticks.rs:154:8
[INFO] [stdout]     |
[INFO] [stdout] 153 | pub trait StickCanonical {
[INFO] [stdout]     |           -------------- associated function in this trait
[INFO] [stdout] 154 |     fn is_same_char(c: char) -> bool;
[INFO] [stdout]     |        ^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `height` is never read
[INFO] [stdout]   --> fvtree/src/confstats.rs:94:9
[INFO] [stdout]    |
[INFO] [stdout] 93 | pub struct TreeStats {
[INFO] [stdout]    |            --------- field in this struct
[INFO] [stdout] 94 |     pub height: usize,
[INFO] [stdout]    |         ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `gen_default_bias` and `add_with_bias` are never used
[INFO] [stdout]   --> fvtree/src/choose_amongst.rs:51:8
[INFO] [stdout]    |
[INFO] [stdout] 26 | impl<T: Copy + Debug> Lottery<'_, T> {
[INFO] [stdout]    | ------------------------------------ methods in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 51 |     fn gen_default_bias(&mut self) {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 57 |     pub fn add_with_bias(&mut self, outcome: T, bias: usize) {
[INFO] [stdout]    |            ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling fvt v0.1.0 (/opt/rustwide/workdir/fvt)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.65s
[INFO] running `Command { std: "docker" "inspect" "92e0befb029be9d804b93318894f8211c4622de04b660881c34433f1c7c0fc45", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "92e0befb029be9d804b93318894f8211c4622de04b660881c34433f1c7c0fc45", kill_on_drop: false }`
[INFO] [stdout] 92e0befb029be9d804b93318894f8211c4622de04b660881c34433f1c7c0fc45
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f15dc8e83ecbc27628c69d1398e5c572345a984befe4dbbe5295e0ccccd9fbb3
[INFO] running `Command { std: "docker" "start" "-a" "f15dc8e83ecbc27628c69d1398e5c572345a984befe4dbbe5295e0ccccd9fbb3", kill_on_drop: false }`
[INFO] [stderr]    Compiling common v0.1.0 (/opt/rustwide/workdir/common)
[INFO] [stderr]    Compiling text_canvas v0.1.0 (/opt/rustwide/workdir/text_canvas)
[INFO] [stdout] warning: unused import: `rand::Rng`
[INFO] [stdout]  --> fvtree/src/tree_gen_recursive.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use rand::Rng;
[INFO] [stdout]   |     ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `TreeStats`
[INFO] [stdout]  --> fvtree/src/tree_gen_recursive.rs:4:39
[INFO] [stdout]   |
[INFO] [stdout] 4 | use crate::confstats::{Stats, Config, TreeStats, BranchStats};
[INFO] [stdout]   |                                       ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: denote infinite loops with `loop { ... }`
[INFO] [stdout]    --> fvtree/src/tree_gen_recursive.rs:161:5
[INFO] [stdout]     |
[INFO] [stdout] 161 |     while true {
[INFO] [stdout]     |     ^^^^^^^^^^ help: use `loop`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(while_true)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `is_same_char` is never used
[INFO] [stdout]    --> fvtree/src/sticks.rs:154:8
[INFO] [stdout]     |
[INFO] [stdout] 153 | pub trait StickCanonical {
[INFO] [stdout]     |           -------------- associated function in this trait
[INFO] [stdout] 154 |     fn is_same_char(c: char) -> bool;
[INFO] [stdout]     |        ^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `height` is never read
[INFO] [stdout]   --> fvtree/src/confstats.rs:94:9
[INFO] [stdout]    |
[INFO] [stdout] 93 | pub struct TreeStats {
[INFO] [stdout]    |            --------- field in this struct
[INFO] [stdout] 94 |     pub height: usize,
[INFO] [stdout]    |         ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling fvtree v0.1.0 (/opt/rustwide/workdir/fvtree)
[INFO] [stdout] warning: methods `gen_default_bias` and `add_with_bias` are never used
[INFO] [stdout]   --> fvtree/src/choose_amongst.rs:51:8
[INFO] [stdout]    |
[INFO] [stdout] 26 | impl<T: Copy + Debug> Lottery<'_, T> {
[INFO] [stdout]    | ------------------------------------ methods in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 51 |     fn gen_default_bias(&mut self) {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 57 |     pub fn add_with_bias(&mut self, outcome: T, bias: usize) {
[INFO] [stdout]    |            ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling fvt v0.1.0 (/opt/rustwide/workdir/fvt)
[INFO] [stdout] warning: unused import: `rand::Rng`
[INFO] [stdout]  --> fvtree/src/tree_gen_recursive.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use rand::Rng;
[INFO] [stdout]   |     ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `TreeStats`
[INFO] [stdout]  --> fvtree/src/tree_gen_recursive.rs:4:39
[INFO] [stdout]   |
[INFO] [stdout] 4 | use crate::confstats::{Stats, Config, TreeStats, BranchStats};
[INFO] [stdout]   |                                       ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: denote infinite loops with `loop { ... }`
[INFO] [stdout]    --> fvtree/src/tree_gen_recursive.rs:161:5
[INFO] [stdout]     |
[INFO] [stdout] 161 |     while true {
[INFO] [stdout]     |     ^^^^^^^^^^ help: use `loop`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(while_true)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::*`
[INFO] [stdout]    --> fvtree/src/lib.rs:164:9
[INFO] [stdout]     |
[INFO] [stdout] 164 |     use super::*;
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]    --> fvtree/src/choose_amongst.rs:146:13
[INFO] [stdout]     |
[INFO] [stdout] 146 |         let num: f32 = lot.choose();
[INFO] [stdout]     |             ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `is_same_char` is never used
[INFO] [stdout]    --> fvtree/src/sticks.rs:154:8
[INFO] [stdout]     |
[INFO] [stdout] 153 | pub trait StickCanonical {
[INFO] [stdout]     |           -------------- associated function in this trait
[INFO] [stdout] 154 |     fn is_same_char(c: char) -> bool;
[INFO] [stdout]     |        ^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `height` is never read
[INFO] [stdout]   --> fvtree/src/confstats.rs:94:9
[INFO] [stdout]    |
[INFO] [stdout] 93 | pub struct TreeStats {
[INFO] [stdout]    |            --------- field in this struct
[INFO] [stdout] 94 |     pub height: usize,
[INFO] [stdout]    |         ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `gen_default_bias` and `add_with_bias` are never used
[INFO] [stdout]   --> fvtree/src/choose_amongst.rs:51:8
[INFO] [stdout]    |
[INFO] [stdout] 26 | impl<T: Copy + Debug> Lottery<'_, T> {
[INFO] [stdout]    | ------------------------------------ methods in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 51 |     fn gen_default_bias(&mut self) {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 57 |     pub fn add_with_bias(&mut self, outcome: T, bias: usize) {
[INFO] [stdout]    |            ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.23s
[INFO] running `Command { std: "docker" "inspect" "f15dc8e83ecbc27628c69d1398e5c572345a984befe4dbbe5295e0ccccd9fbb3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f15dc8e83ecbc27628c69d1398e5c572345a984befe4dbbe5295e0ccccd9fbb3", kill_on_drop: false }`
[INFO] [stdout] f15dc8e83ecbc27628c69d1398e5c572345a984befe4dbbe5295e0ccccd9fbb3