[INFO] updating cached repository https://github.com/andresilva/rust-okasaki
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] da0f298d49be46ba9899f78944ec2b0fbbf64885
[INFO] checking andresilva/rust-okasaki against try#e4dba30b9b475d8750370c4dfb49b6541990904d for pr-71393
[INFO] running `"git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fandresilva%2Frust-okasaki" "/workspace/builds/worker-13/source"`
[INFO] [stderr] Cloning into '/workspace/builds/worker-13/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/andresilva/rust-okasaki on toolchain e4dba30b9b475d8750370c4dfb49b6541990904d
[INFO] running `"/workspace/cargo-home/bin/cargo" "+e4dba30b9b475d8750370c4dfb49b6541990904d" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/andresilva/rust-okasaki
[INFO] finished tweaking git repo https://github.com/andresilva/rust-okasaki
[INFO] tweaked toml for git repo https://github.com/andresilva/rust-okasaki written to /workspace/builds/worker-13/source/Cargo.toml
[INFO] crate git repo https://github.com/andresilva/rust-okasaki already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+e4dba30b9b475d8750370c4dfb49b6541990904d" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+e4dba30b9b475d8750370c4dfb49b6541990904d" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 0f1c0814f7191c4a6bcf3297917e6f8cccf5c5c4b7f5a1fbbae7cb35da66efa5
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `"docker" "start" "-a" "0f1c0814f7191c4a6bcf3297917e6f8cccf5c5c4b7f5a1fbbae7cb35da66efa5"`
[INFO] [stderr]     Checking okasaki v0.0.1 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0432]: unresolved import `std::num::Int`
[INFO] [stderr]  --> src/tree.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::num::Int;
[INFO] [stderr]   |     ^^^^^^^^^^^^^ no `Int` in `num`
[INFO] [stderr] 
[INFO] [stderr] error[E0432]: unresolved import `std::num::Float`
[INFO] [stderr]  --> src/tree_layout.rs:2:5
[INFO] [stderr]   |
[INFO] [stderr] 2 | use std::num::Float;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^ no `Float` in `num`
[INFO] [stderr] 
[INFO] [stderr] error[E0432]: unresolved import `std::num::Int`
[INFO] [stderr]  --> src/tree.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::num::Int;
[INFO] [stderr]   |     ^^^^^^^^^^^^^ no `Int` in `num`
[INFO] [stderr] 
[INFO] [stderr] error[E0432]: unresolved import `std::num::Float`
[INFO] [stderr]  --> src/tree_layout.rs:2:5
[INFO] [stderr]   |
[INFO] [stderr] 2 | use std::num::Float;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^ no `Float` in `num`
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/heap.rs:87:21
[INFO] [stderr]    |
[INFO] [stderr] 87 |                     try!(aux(f, r, true, &(indent.to_string() + if right { "        " } else { " |      " })));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(deprecated)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/heap.rs:89:21
[INFO] [stderr]    |
[INFO] [stderr] 89 |                     try!(write!(f, "{}", indent));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/heap.rs:90:21
[INFO] [stderr]    |
[INFO] [stderr] 90 |                     try!(if right { write!(f, "{}", " /") } else { write!(f, "{}", " \\") });
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/heap.rs:91:21
[INFO] [stderr]    |
[INFO] [stderr] 91 |                     try!(write!(f, "{}", "----- "));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/heap.rs:93:21
[INFO] [stderr]    |
[INFO] [stderr] 93 |                     try!(writeln!(f, "(#{}, {})", rank, x));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/heap.rs:98:21
[INFO] [stderr]    |
[INFO] [stderr] 98 |                     try!(write!(f, "{}", indent));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/heap.rs:99:21
[INFO] [stderr]    |
[INFO] [stderr] 99 |                     try!(if right { write!(f, "{}", " /") } else { write!(f, "{}", " \\") });
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/heap.rs:100:21
[INFO] [stderr]     |
[INFO] [stderr] 100 |                     try!(write!(f, "{}", "----- "));
[INFO] [stderr]     |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/heap.rs:109:17
[INFO] [stderr]     |
[INFO] [stderr] 109 |                 try!(aux(f, r, true, ""));
[INFO] [stderr]     |                 ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/heap.rs:110:17
[INFO] [stderr]     |
[INFO] [stderr] 110 |                 try!(writeln!(f, "(#{}, {})", rank, x));
[INFO] [stderr]     |                 ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/stack.rs:77:9
[INFO] [stderr]    |
[INFO] [stderr] 77 |         try!(write!(f, "["));
[INFO] [stderr]    |         ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/stack.rs:82:32
[INFO] [stderr]    |
[INFO] [stderr] 82 |                     if first { try!(write!(f, "{}", h)); }
[INFO] [stderr]    |                                ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/stack.rs:83:28
[INFO] [stderr]    |
[INFO] [stderr] 83 |                     else { try!(write!(f, ", {}", h)); }
[INFO] [stderr]    |                            ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/stack.rs:91:9
[INFO] [stderr]    |
[INFO] [stderr] 91 |         try!(_loop(f, self, true));
[INFO] [stderr]    |         ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/heap.rs:87:21
[INFO] [stderr]    |
[INFO] [stderr] 87 |                     try!(aux(f, r, true, &(indent.to_string() + if right { "        " } else { " |      " })));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(deprecated)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/heap.rs:89:21
[INFO] [stderr]    |
[INFO] [stderr] 89 |                     try!(write!(f, "{}", indent));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/heap.rs:90:21
[INFO] [stderr]    |
[INFO] [stderr] 90 |                     try!(if right { write!(f, "{}", " /") } else { write!(f, "{}", " \\") });
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/heap.rs:91:21
[INFO] [stderr]    |
[INFO] [stderr] 91 |                     try!(write!(f, "{}", "----- "));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/heap.rs:93:21
[INFO] [stderr]    |
[INFO] [stderr] 93 |                     try!(writeln!(f, "(#{}, {})", rank, x));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/heap.rs:98:21
[INFO] [stderr]    |
[INFO] [stderr] 98 |                     try!(write!(f, "{}", indent));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/heap.rs:99:21
[INFO] [stderr]    |
[INFO] [stderr] 99 |                     try!(if right { write!(f, "{}", " /") } else { write!(f, "{}", " \\") });
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/heap.rs:100:21
[INFO] [stderr]     |
[INFO] [stderr] 100 |                     try!(write!(f, "{}", "----- "));
[INFO] [stderr]     |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/heap.rs:109:17
[INFO] [stderr]     |
[INFO] [stderr] 109 |                 try!(aux(f, r, true, ""));
[INFO] [stderr]     |                 ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/heap.rs:110:17
[INFO] [stderr]     |
[INFO] [stderr] 110 |                 try!(writeln!(f, "(#{}, {})", rank, x));
[INFO] [stderr]     |                 ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/stack.rs:77:9
[INFO] [stderr]    |
[INFO] [stderr] 77 |         try!(write!(f, "["));
[INFO] [stderr]    |         ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/stack.rs:82:32
[INFO] [stderr]    |
[INFO] [stderr] 82 |                     if first { try!(write!(f, "{}", h)); }
[INFO] [stderr]    |                                ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/stack.rs:83:28
[INFO] [stderr]    |
[INFO] [stderr] 83 |                     else { try!(write!(f, ", {}", h)); }
[INFO] [stderr]    |                            ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/stack.rs:91:9
[INFO] [stderr]    |
[INFO] [stderr] 91 |         try!(_loop(f, self, true));
[INFO] [stderr]    |         ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:19:21
[INFO] [stderr]    |
[INFO] [stderr] 19 |                     try!(aux(f, r, true, &(indent.to_string() + if right { "        " } else { " |      " })));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:21:21
[INFO] [stderr]    |
[INFO] [stderr] 21 |                     try!(write!(f, "{}", indent));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:19:21
[INFO] [stderr]    |
[INFO] [stderr] 19 |                     try!(aux(f, r, true, &(indent.to_string() + if right { "        " } else { " |      " })));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:22:21
[INFO] [stderr]    |
[INFO] [stderr] 22 |                     try!(if right { write!(f, "{}", " /") } else { write!(f, "{}", " \\") });
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:23:21
[INFO] [stderr]    |
[INFO] [stderr] 23 |                     try!(write!(f, "{}", "----- "));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:21:21
[INFO] [stderr]    |
[INFO] [stderr] 21 |                     try!(write!(f, "{}", indent));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:25:21
[INFO] [stderr]    |
[INFO] [stderr] 25 |                     try!(writeln!(f, "({})", x));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:22:21
[INFO] [stderr]    |
[INFO] [stderr] 22 |                     try!(if right { write!(f, "{}", " /") } else { write!(f, "{}", " \\") });
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:30:21
[INFO] [stderr]    |
[INFO] [stderr] 30 |                     try!(write!(f, "{}", indent));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:23:21
[INFO] [stderr]    |
[INFO] [stderr] 23 |                     try!(write!(f, "{}", "----- "));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:31:21
[INFO] [stderr]    |
[INFO] [stderr] 31 |                     try!(if right { write!(f, "{}", " /") } else { write!(f, "{}", " \\") });
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:25:21
[INFO] [stderr]    |
[INFO] [stderr] 25 |                     try!(writeln!(f, "({})", x));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:32:21
[INFO] [stderr]    |
[INFO] [stderr] 32 |                     try!(write!(f, "{}", "----- "));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:30:21
[INFO] [stderr]    |
[INFO] [stderr] 30 |                     try!(write!(f, "{}", indent));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:31:21
[INFO] [stderr]    |
[INFO] [stderr] 31 |                     try!(if right { write!(f, "{}", " /") } else { write!(f, "{}", " \\") });
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:41:17
[INFO] [stderr]    |
[INFO] [stderr] 41 |                 try!(aux(f, r, true, ""));
[INFO] [stderr]    |                 ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:32:21
[INFO] [stderr]    |
[INFO] [stderr] 32 |                     try!(write!(f, "{}", "----- "));
[INFO] [stderr]    |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:42:17
[INFO] [stderr]    |
[INFO] [stderr] 42 |                 try!(writeln!(f, "({})", x));
[INFO] [stderr]    |                 ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:41:17
[INFO] [stderr]    |
[INFO] [stderr] 41 |                 try!(aux(f, r, true, ""));
[INFO] [stderr]    |                 ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/trie.rs:115:21
[INFO] [stderr]     |
[INFO] [stderr] 115 |                     try!(write!(f, "{}", indent));
[INFO] [stderr]     |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]   --> src/tree.rs:42:17
[INFO] [stderr]    |
[INFO] [stderr] 42 |                 try!(writeln!(f, "({})", x));
[INFO] [stderr]    |                 ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/trie.rs:118:25
[INFO] [stderr]     |
[INFO] [stderr] 118 |                         try!(write!(f, "\\-"));
[INFO] [stderr]     |                         ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/trie.rs:115:21
[INFO] [stderr]     |
[INFO] [stderr] 115 |                     try!(write!(f, "{}", indent));
[INFO] [stderr]     |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/trie.rs:121:25
[INFO] [stderr]     |
[INFO] [stderr] 121 |                         try!(write!(f, "|-"));
[INFO] [stderr]     |                         ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/trie.rs:118:25
[INFO] [stderr]     |
[INFO] [stderr] 118 |                         try!(write!(f, "\\-"));
[INFO] [stderr]     |                         ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/trie.rs:125:21
[INFO] [stderr]     |
[INFO] [stderr] 125 |                     try!(write!(f, "{}", key));
[INFO] [stderr]     |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/trie.rs:128:40
[INFO] [stderr]     |
[INFO] [stderr] 128 |                         Some(ref v) => try!(write!(f, " => ({})", v)),
[INFO] [stderr]     |                                        ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/trie.rs:132:21
[INFO] [stderr]     |
[INFO] [stderr] 132 |                     try!(writeln!(f, ""));
[INFO] [stderr]     |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/trie.rs:135:25
[INFO] [stderr]     |
[INFO] [stderr] 135 |                         try!(aux(c, indent.clone(), i == children.len() - 1, f));
[INFO] [stderr]     |                         ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `if` condition
[INFO] [stderr]    --> src/heap.rs:184:16
[INFO] [stderr]     |
[INFO] [stderr] 184 |             if (root(t) < root(&t1)) {
[INFO] [stderr]     |                ^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_parens)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/trie.rs:121:25
[INFO] [stderr]     |
[INFO] [stderr] 121 |                         try!(write!(f, "|-"));
[INFO] [stderr]     |                         ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/trie.rs:125:21
[INFO] [stderr]     |
[INFO] [stderr] 125 |                     try!(write!(f, "{}", key));
[INFO] [stderr]     |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/trie.rs:128:40
[INFO] [stderr]     |
[INFO] [stderr] 128 |                         Some(ref v) => try!(write!(f, " => ({})", v)),
[INFO] [stderr]     |                                        ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/trie.rs:132:21
[INFO] [stderr]     |
[INFO] [stderr] 132 |                     try!(writeln!(f, ""));
[INFO] [stderr]     |                     ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::cmp::max`
[INFO] [stderr]  --> src/tree.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::cmp::max;
[INFO] [stderr]   |     ^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `for` iterator expression
[INFO] [stderr]   --> src/tree_layout.rs:14:18
[INFO] [stderr]    |
[INFO] [stderr] 14 |         for _ in (0..n) {
[INFO] [stderr]    |                  ^^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: use of deprecated item 'try': use the `?` operator instead
[INFO] [stderr]    --> src/trie.rs:135:25
[INFO] [stderr]     |
[INFO] [stderr] 135 |                         try!(aux(c, indent.clone(), i == children.len() - 1, f));
[INFO] [stderr]     |                         ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `if` condition
[INFO] [stderr]    --> src/heap.rs:184:16
[INFO] [stderr]     |
[INFO] [stderr] 184 |             if (root(t) < root(&t1)) {
[INFO] [stderr]     |                ^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_parens)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::cmp::max`
[INFO] [stderr]  --> src/tree.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::cmp::max;
[INFO] [stderr]   |     ^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `for` iterator expression
[INFO] [stderr]   --> src/tree_layout.rs:14:18
[INFO] [stderr]    |
[INFO] [stderr] 14 |         for _ in (0..n) {
[INFO] [stderr]    |                  ^^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `tail` found for struct `std::vec::Vec<tree::Tree<(T, f64)>>` in the current scope
[INFO] [stderr]   --> src/tree_layout.rs:45:29
[INFO] [stderr]    |
[INFO] [stderr] 45 |                 aux(current.tail().to_vec(), next, o);
[INFO] [stderr]    |                             ^^^^ method not found in `std::vec::Vec<tree::Tree<(T, f64)>>`
[INFO] [stderr]    |
[INFO] [stderr]    = help: items from traits can only be used if the trait is implemented and in scope
[INFO] [stderr] note: `stack::Stack` defines an item `tail`, perhaps you need to implement it
[INFO] [stderr]   --> src/stack.rs:4:1
[INFO] [stderr]    |
[INFO] [stderr] 4  | pub trait Stack<T> {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0606]: casting `f64` as `usize` is invalid
[INFO] [stderr]   --> src/tree_layout.rs:36:38
[INFO] [stderr]    |
[INFO] [stderr] 36 |                         print_spaces((sp * factor) as usize);
[INFO] [stderr]    |                                      ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `tail` found for struct `std::vec::Vec<std::vec::Vec<(f64, f64)>>` in the current scope
[INFO] [stderr]    --> src/tree_layout.rs:172:36
[INFO] [stderr]     |
[INFO] [stderr] 172 |                 let mut r = aux(es.tail().to_vec(), merge_extent(acc.clone(), move_extent(e.clone().to_vec(), x)));
[INFO] [stderr]     |                                    ^^^^ method not found in `std::vec::Vec<std::vec::Vec<(f64, f64)>>`
[INFO] [stderr]     |
[INFO] [stderr]     = help: items from traits can only be used if the trait is implemented and in scope
[INFO] [stderr] note: `stack::Stack` defines an item `tail`, perhaps you need to implement it
[INFO] [stderr]    --> src/stack.rs:4:1
[INFO] [stderr]     |
[INFO] [stderr] 4   | pub trait Stack<T> {
[INFO] [stderr]     | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `tail` found for struct `std::vec::Vec<(f64, f64)>` in the current scope
[INFO] [stderr]    --> src/tree_layout.rs:189:25
[INFO] [stderr]     |
[INFO] [stderr] 189 |             rmax(fit(e1.tail().to_vec(), e2.tail().to_vec()), p - q + 1.0),
[INFO] [stderr]     |                         ^^^^ method not found in `std::vec::Vec<(f64, f64)>`
[INFO] [stderr]     |
[INFO] [stderr]     = help: items from traits can only be used if the trait is implemented and in scope
[INFO] [stderr] note: `stack::Stack` defines an item `tail`, perhaps you need to implement it
[INFO] [stderr]    --> src/stack.rs:4:1
[INFO] [stderr]     |
[INFO] [stderr] 4   | pub trait Stack<T> {
[INFO] [stderr]     | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `tail` found for struct `std::vec::Vec<(f64, f64)>` in the current scope
[INFO] [stderr]    --> src/tree_layout.rs:189:45
[INFO] [stderr]     |
[INFO] [stderr] 189 |             rmax(fit(e1.tail().to_vec(), e2.tail().to_vec()), p - q + 1.0),
[INFO] [stderr]     |                                             ^^^^ method not found in `std::vec::Vec<(f64, f64)>`
[INFO] [stderr]     |
[INFO] [stderr]     = help: items from traits can only be used if the trait is implemented and in scope
[INFO] [stderr] note: `stack::Stack` defines an item `tail`, perhaps you need to implement it
[INFO] [stderr]    --> src/stack.rs:4:1
[INFO] [stderr]     |
[INFO] [stderr] 4   | pub trait Stack<T> {
[INFO] [stderr]     | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `tail` found for struct `std::vec::Vec<(f64, f64)>` in the current scope
[INFO] [stderr]    --> src/tree_layout.rs:199:41
[INFO] [stderr]     |
[INFO] [stderr] 199 |             let mut m = merge_extent(e1.tail().to_vec(), e2.tail().to_vec());
[INFO] [stderr]     |                                         ^^^^ method not found in `std::vec::Vec<(f64, f64)>`
[INFO] [stderr]     |
[INFO] [stderr]     = help: items from traits can only be used if the trait is implemented and in scope
[INFO] [stderr] note: `stack::Stack` defines an item `tail`, perhaps you need to implement it
[INFO] [stderr]    --> src/stack.rs:4:1
[INFO] [stderr]     |
[INFO] [stderr] 4   | pub trait Stack<T> {
[INFO] [stderr]     | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `tail` found for struct `std::vec::Vec<(f64, f64)>` in the current scope
[INFO] [stderr]    --> src/tree_layout.rs:199:61
[INFO] [stderr]     |
[INFO] [stderr] 199 |             let mut m = merge_extent(e1.tail().to_vec(), e2.tail().to_vec());
[INFO] [stderr]     |                                                             ^^^^ method not found in `std::vec::Vec<(f64, f64)>`
[INFO] [stderr]     |
[INFO] [stderr]     = help: items from traits can only be used if the trait is implemented and in scope
[INFO] [stderr] note: `stack::Stack` defines an item `tail`, perhaps you need to implement it
[INFO] [stderr]    --> src/stack.rs:4:1
[INFO] [stderr]     |
[INFO] [stderr] 4   | pub trait Stack<T> {
[INFO] [stderr]     | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `tail` found for struct `std::vec::Vec<tree::Tree<(T, f64)>>` in the current scope
[INFO] [stderr]   --> src/tree_layout.rs:45:29
[INFO] [stderr]    |
[INFO] [stderr] 45 |                 aux(current.tail().to_vec(), next, o);
[INFO] [stderr]    |                             ^^^^ method not found in `std::vec::Vec<tree::Tree<(T, f64)>>`
[INFO] [stderr]    |
[INFO] [stderr]    = help: items from traits can only be used if the trait is implemented and in scope
[INFO] [stderr] note: `stack::Stack` defines an item `tail`, perhaps you need to implement it
[INFO] [stderr]   --> src/stack.rs:4:1
[INFO] [stderr]    |
[INFO] [stderr] 4  | pub trait Stack<T> {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0606]: casting `f64` as `usize` is invalid
[INFO] [stderr]   --> src/tree_layout.rs:36:38
[INFO] [stderr]    |
[INFO] [stderr] 36 |                         print_spaces((sp * factor) as usize);
[INFO] [stderr]    |                                      ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `char_at` found for reference `&str` in the current scope
[INFO] [stderr]   --> src/trie.rs:59:40
[INFO] [stderr]    |
[INFO] [stderr] 59 |                     children.insert(k1.char_at(0), Rc::new(add_children(self, k1.to_string(), v)));
[INFO] [stderr]    |                                        ^^^^^^^ method not found in `&str`
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `char_at` found for reference `&str` in the current scope
[INFO] [stderr]   --> src/trie.rs:67:28
[INFO] [stderr]    |
[INFO] [stderr] 67 |                         k1.char_at(0) => Rc::new(Node { key: k1.to_string(), value: value.clone(), children: children.clone() })];
[INFO] [stderr]    |                            ^^^^^^^ method not found in `&str`
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `char_at` found for reference `&str` in the current scope
[INFO] [stderr]   --> src/trie.rs:78:28
[INFO] [stderr]    |
[INFO] [stderr] 78 |                         k1.char_at(0) => Rc::new(Node { key: k1.to_string(), value: value.clone(), children: children.clone() }),
[INFO] [stderr]    |                            ^^^^^^^ method not found in `&str`
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `char_at` found for reference `&str` in the current scope
[INFO] [stderr]   --> src/trie.rs:79:28
[INFO] [stderr]    |
[INFO] [stderr] 79 |                         k2.char_at(0) => Rc::new(Node { key: k2.to_string(), value: Some(v), children: hashmap![] })];
[INFO] [stderr]    |                            ^^^^^^^ method not found in `&str`
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `char_at` found for struct `std::string::String` in the current scope
[INFO] [stderr]   --> src/trie.rs:38:43
[INFO] [stderr]    |
[INFO] [stderr] 38 |                     match children.get(&k.char_at(0)) {
[INFO] [stderr]    |                                           ^^^^^^^ method not found in `std::string::String`
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `char_at` found for struct `std::string::String` in the current scope
[INFO] [stderr]   --> src/trie.rs:97:43
[INFO] [stderr]    |
[INFO] [stderr] 97 |                     match children.get(&k.char_at(key.len())) {
[INFO] [stderr]    |                                           ^^^^^^^ method not found in `std::string::String`
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `tail` found for struct `std::vec::Vec<std::vec::Vec<(f64, f64)>>` in the current scope
[INFO] [stderr]    --> src/tree_layout.rs:172:36
[INFO] [stderr]     |
[INFO] [stderr] 172 |                 let mut r = aux(es.tail().to_vec(), merge_extent(acc.clone(), move_extent(e.clone().to_vec(), x)));
[INFO] [stderr]     |                                    ^^^^ method not found in `std::vec::Vec<std::vec::Vec<(f64, f64)>>`
[INFO] [stderr]     |
[INFO] [stderr]     = help: items from traits can only be used if the trait is implemented and in scope
[INFO] [stderr] note: `stack::Stack` defines an item `tail`, perhaps you need to implement it
[INFO] [stderr]    --> src/stack.rs:4:1
[INFO] [stderr]     |
[INFO] [stderr] 4   | pub trait Stack<T> {
[INFO] [stderr]     | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `tail` found for struct `std::vec::Vec<(f64, f64)>` in the current scope
[INFO] [stderr]    --> src/tree_layout.rs:189:25
[INFO] [stderr]     |
[INFO] [stderr] 189 |             rmax(fit(e1.tail().to_vec(), e2.tail().to_vec()), p - q + 1.0),
[INFO] [stderr]     |                         ^^^^ method not found in `std::vec::Vec<(f64, f64)>`
[INFO] [stderr]     |
[INFO] [stderr]     = help: items from traits can only be used if the trait is implemented and in scope
[INFO] [stderr] note: `stack::Stack` defines an item `tail`, perhaps you need to implement it
[INFO] [stderr]    --> src/stack.rs:4:1
[INFO] [stderr]     |
[INFO] [stderr] 4   | pub trait Stack<T> {
[INFO] [stderr]     | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `tail` found for struct `std::vec::Vec<(f64, f64)>` in the current scope
[INFO] [stderr]    --> src/tree_layout.rs:189:45
[INFO] [stderr]     |
[INFO] [stderr] 189 |             rmax(fit(e1.tail().to_vec(), e2.tail().to_vec()), p - q + 1.0),
[INFO] [stderr]     |                                             ^^^^ method not found in `std::vec::Vec<(f64, f64)>`
[INFO] [stderr]     |
[INFO] [stderr]     = help: items from traits can only be used if the trait is implemented and in scope
[INFO] [stderr] note: `stack::Stack` defines an item `tail`, perhaps you need to implement it
[INFO] [stderr]    --> src/stack.rs:4:1
[INFO] [stderr]     |
[INFO] [stderr] 4   | pub trait Stack<T> {
[INFO] [stderr]     | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 15 previous errors; 34 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0432, E0599, E0606.
[INFO] [stderr] For more information about an error, try `rustc --explain E0432`.
[INFO] [stderr] error[E0599]: no method named `tail` found for struct `std::vec::Vec<(f64, f64)>` in the current scope
[INFO] [stderr]    --> src/tree_layout.rs:199:41
[INFO] [stderr]     |
[INFO] [stderr] 199 |             let mut m = merge_extent(e1.tail().to_vec(), e2.tail().to_vec());
[INFO] [stderr]     |                                         ^^^^ method not found in `std::vec::Vec<(f64, f64)>`
[INFO] [stderr]     |
[INFO] [stderr]     = help: items from traits can only be used if the trait is implemented and in scope
[INFO] [stderr] note: `stack::Stack` defines an item `tail`, perhaps you need to implement it
[INFO] [stderr]    --> src/stack.rs:4:1
[INFO] [stderr]     |
[INFO] [stderr] 4   | pub trait Stack<T> {
[INFO] [stderr]     | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `tail` found for struct `std::vec::Vec<(f64, f64)>` in the current scope
[INFO] [stderr]    --> src/tree_layout.rs:199:61
[INFO] [stderr]     |
[INFO] [stderr] 199 |             let mut m = merge_extent(e1.tail().to_vec(), e2.tail().to_vec());
[INFO] [stderr]     |                                                             ^^^^ method not found in `std::vec::Vec<(f64, f64)>`
[INFO] [stderr]     |
[INFO] [stderr]     = help: items from traits can only be used if the trait is implemented and in scope
[INFO] [stderr] note: `stack::Stack` defines an item `tail`, perhaps you need to implement it
[INFO] [stderr]    --> src/stack.rs:4:1
[INFO] [stderr]     |
[INFO] [stderr] 4   | pub trait Stack<T> {
[INFO] [stderr]     | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: could not compile `okasaki`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error[E0599]: no method named `char_at` found for reference `&str` in the current scope
[INFO] [stderr]   --> src/trie.rs:59:40
[INFO] [stderr]    |
[INFO] [stderr] 59 |                     children.insert(k1.char_at(0), Rc::new(add_children(self, k1.to_string(), v)));
[INFO] [stderr]    |                                        ^^^^^^^ method not found in `&str`
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `char_at` found for reference `&str` in the current scope
[INFO] [stderr]   --> src/trie.rs:67:28
[INFO] [stderr]    |
[INFO] [stderr] 67 |                         k1.char_at(0) => Rc::new(Node { key: k1.to_string(), value: value.clone(), children: children.clone() })];
[INFO] [stderr]    |                            ^^^^^^^ method not found in `&str`
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `char_at` found for reference `&str` in the current scope
[INFO] [stderr]   --> src/trie.rs:78:28
[INFO] [stderr]    |
[INFO] [stderr] 78 |                         k1.char_at(0) => Rc::new(Node { key: k1.to_string(), value: value.clone(), children: children.clone() }),
[INFO] [stderr]    |                            ^^^^^^^ method not found in `&str`
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `char_at` found for reference `&str` in the current scope
[INFO] [stderr]   --> src/trie.rs:79:28
[INFO] [stderr]    |
[INFO] [stderr] 79 |                         k2.char_at(0) => Rc::new(Node { key: k2.to_string(), value: Some(v), children: hashmap![] })];
[INFO] [stderr]    |                            ^^^^^^^ method not found in `&str`
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `char_at` found for struct `std::string::String` in the current scope
[INFO] [stderr]   --> src/trie.rs:38:43
[INFO] [stderr]    |
[INFO] [stderr] 38 |                     match children.get(&k.char_at(0)) {
[INFO] [stderr]    |                                           ^^^^^^^ method not found in `std::string::String`
[INFO] [stderr] 
[INFO] [stderr] error[E0599]: no method named `char_at` found for struct `std::string::String` in the current scope
[INFO] [stderr]   --> src/trie.rs:97:43
[INFO] [stderr]    |
[INFO] [stderr] 97 |                     match children.get(&k.char_at(key.len())) {
[INFO] [stderr]    |                                           ^^^^^^^ method not found in `std::string::String`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 15 previous errors; 34 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0432, E0599, E0606.
[INFO] [stderr] For more information about an error, try `rustc --explain E0432`.
[INFO] [stderr] error: could not compile `okasaki`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "0f1c0814f7191c4a6bcf3297917e6f8cccf5c5c4b7f5a1fbbae7cb35da66efa5"`
[INFO] running `"docker" "rm" "-f" "0f1c0814f7191c4a6bcf3297917e6f8cccf5c5c4b7f5a1fbbae7cb35da66efa5"`
[INFO] [stdout] 0f1c0814f7191c4a6bcf3297917e6f8cccf5c5c4b7f5a1fbbae7cb35da66efa5