[INFO] fetching crate qp-trie 0.7.6...
[INFO] testing qp-trie-0.7.6 against 1.49.0 for beta-1.50-1
[INFO] extracting crate qp-trie 0.7.6 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate qp-trie 0.7.6 on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate qp-trie 0.7.6
[INFO] finished tweaking crates.io crate qp-trie 0.7.6
[INFO] tweaked toml for crates.io crate qp-trie 0.7.6 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 647e04e360ccf2734a443bae5a16ccd28aa62b33af8e9c874bae5b284ee11c02
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "647e04e360ccf2734a443bae5a16ccd28aa62b33af8e9c874bae5b284ee11c02", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "647e04e360ccf2734a443bae5a16ccd28aa62b33af8e9c874bae5b284ee11c02", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "647e04e360ccf2734a443bae5a16ccd28aa62b33af8e9c874bae5b284ee11c02", kill_on_drop: false }`
[INFO] [stdout] 647e04e360ccf2734a443bae5a16ccd28aa62b33af8e9c874bae5b284ee11c02
[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=warn" "-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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 33271d9dac1f1efe34a648bcf946338ed6509cbfbf1c06369e0248d8f90ae45e
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "33271d9dac1f1efe34a648bcf946338ed6509cbfbf1c06369e0248d8f90ae45e", kill_on_drop: false }`
[INFO] [stderr]    Compiling void v1.0.2
[INFO] [stderr]    Compiling new_debug_unreachable v1.0.4
[INFO] [stderr]    Compiling unreachable v1.0.0
[INFO] [stderr]    Compiling qp-trie v0.7.6 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/node.rs:495:21
[INFO] [stdout]     |
[INFO] [stdout] 495 |                     mem::replace(self, Node::Branch(branch));
[INFO] [stdout]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/node.rs:606:21
[INFO] [stdout]     |
[INFO] [stdout] 606 |                     mem::replace(self, node);
[INFO] [stdout]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/node.rs:669:21
[INFO] [stdout]     |
[INFO] [stdout] 669 |                     mem::replace(self, node);
[INFO] [stdout]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.17s
[INFO] running `Command { std: "docker" "inspect" "33271d9dac1f1efe34a648bcf946338ed6509cbfbf1c06369e0248d8f90ae45e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "33271d9dac1f1efe34a648bcf946338ed6509cbfbf1c06369e0248d8f90ae45e", kill_on_drop: false }`
[INFO] [stdout] 33271d9dac1f1efe34a648bcf946338ed6509cbfbf1c06369e0248d8f90ae45e
[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=warn" "-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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 195cde647449171814acd07af1807e4435830641367dbd4a5c1db7a1b5e77b5c
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "195cde647449171814acd07af1807e4435830641367dbd4a5c1db7a1b5e77b5c", kill_on_drop: false }`
[INFO] [stderr]    Compiling unreachable v0.1.1
[INFO] [stderr]    Compiling rand_chacha v0.2.2
[INFO] [stderr]    Compiling env_logger v0.7.1
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/node.rs:495:21
[INFO] [stdout]     |
[INFO] [stdout] 495 |                     mem::replace(self, Node::Branch(branch));
[INFO] [stdout]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/node.rs:606:21
[INFO] [stdout]     |
[INFO] [stdout] 606 |                     mem::replace(self, node);
[INFO] [stdout]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/node.rs:669:21
[INFO] [stdout]     |
[INFO] [stdout] 669 |                     mem::replace(self, node);
[INFO] [stdout]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling debug_unreachable v0.1.1
[INFO] [stderr]    Compiling qptrie v0.2.4
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling quickcheck v0.9.2
[INFO] [stderr]    Compiling qp-trie v0.7.6 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/node.rs:495:21
[INFO] [stdout]     |
[INFO] [stdout] 495 |                     mem::replace(self, Node::Branch(branch));
[INFO] [stdout]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/node.rs:606:21
[INFO] [stdout]     |
[INFO] [stdout] 606 |                     mem::replace(self, node);
[INFO] [stdout]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/node.rs:669:21
[INFO] [stdout]     |
[INFO] [stdout] 669 |                     mem::replace(self, node);
[INFO] [stdout]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 14.03s
[INFO] running `Command { std: "docker" "inspect" "195cde647449171814acd07af1807e4435830641367dbd4a5c1db7a1b5e77b5c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "195cde647449171814acd07af1807e4435830641367dbd4a5c1db7a1b5e77b5c", kill_on_drop: false }`
[INFO] [stdout] 195cde647449171814acd07af1807e4435830641367dbd4a5c1db7a1b5e77b5c
[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=warn" "-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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 6b81747751b4c7239423a16637791e83c642fd876d7aa1ecd319da59391e4912
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "6b81747751b4c7239423a16637791e83c642fd876d7aa1ecd319da59391e4912", kill_on_drop: false }`
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/node.rs:495:21
[INFO] [stderr]     |
[INFO] [stderr] 495 |                     mem::replace(self, Node::Branch(branch));
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/node.rs:606:21
[INFO] [stderr]     |
[INFO] [stderr] 606 |                     mem::replace(self, node);
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/node.rs:669:21
[INFO] [stderr]     |
[INFO] [stderr] 669 |                     mem::replace(self, node);
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: 3 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/node.rs:495:21
[INFO] [stderr]     |
[INFO] [stderr] 495 |                     mem::replace(self, Node::Branch(branch));
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/node.rs:606:21
[INFO] [stderr]     |
[INFO] [stderr] 606 |                     mem::replace(self, node);
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]    --> src/node.rs:669:21
[INFO] [stderr]     |
[INFO] [stderr] 669 |                     mem::replace(self, node);
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: 3 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.07s
[INFO] [stdout] 
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/qp_trie-834ad6da618f9214
[INFO] [stdout] running 1 test
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/lib-2f97ecadfcaf2b3c
[INFO] [stdout] test util::test::nybble ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] running 21 tests
[INFO] [stdout] test insert_and_get_3 ... ok
[INFO] [stdout] test insert_and_get_2 ... ok
[INFO] [stdout] test insert_and_get_1 ... ok
[INFO] [stdout] test entry_insert_and_remove_1 ... ok
[INFO] [stdout] test issue_22_regression_remove_prefix ... ok
[INFO] [stdout] test entry_insert_and_remove_2 ... ok
[INFO] [stdout] test prefix_sets_1 ... ok
[INFO] [stdout] test insert_and_remove_1 ... ok
[INFO] [stdout] test insert_and_get_5 ... ok
[INFO] [stdout] test insert_and_get_4 ... ok
[INFO] [stdout] test longest_common_prefix_simple ... ok
[INFO] [stdout] test longest_common_prefix_complex ... ok
[INFO] [stdout] test insert_and_get ... ok
[INFO] [stdout] test prefix_sets_ref ... ok
[INFO] [stdout] test prefix_sets ... ok
[INFO] [stdout] test insert_and_remove ... ok
[INFO] [stdout] test iter_values ... ok
[INFO] [stdout] test iter_keys ... ok
[INFO] [stdout] test entry_insert_and_remove ... ok
[INFO] [stdout] test longest_common_prefix ... ok
[INFO] [stderr]    Doc-tests qp-trie
[INFO] [stdout] test prefix_sets_mut ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 21 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stdout] test src/trie.rs - trie::Trie (line 25) ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "6b81747751b4c7239423a16637791e83c642fd876d7aa1ecd319da59391e4912", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6b81747751b4c7239423a16637791e83c642fd876d7aa1ecd319da59391e4912", kill_on_drop: false }`
[INFO] [stdout] 6b81747751b4c7239423a16637791e83c642fd876d7aa1ecd319da59391e4912