[INFO] fetching crate leveldb 0.8.6...
[INFO] testing leveldb-0.8.6 against 1.69.0 for beta-1.70-1
[INFO] extracting crate leveldb 0.8.6 into /workspace/builds/worker-6-tc1/source
[INFO] validating manifest of crates.io crate leveldb 0.8.6 on toolchain 1.69.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.69.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate leveldb 0.8.6
[INFO] removed 0 missing tests
[INFO] finished tweaking crates.io crate leveldb 0.8.6
[INFO] tweaked toml for crates.io crate leveldb 0.8.6 written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" __CARGO_TEST_CHANNEL_OVERRIDE_DO_NOT_USE_THIS="nightly" "/workspace/cargo-home/bin/cargo" "+1.69.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.69.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded ffi-opaque v2.0.1
[INFO] [stderr]   Downloaded db-key v0.0.5
[INFO] [stderr]   Downloaded leveldb-sys v2.0.9
[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@sha256:5ff2268d62e97bff2cde7d5815dd6ed5b47097566f13b8d0ca110b04b60e07ed" "/opt/rustwide/cargo-home/bin/cargo" "+1.69.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7440a0641f6c5b9a914c4814ea32fec5f5acf2975abe85401912ac1478ff06ae
[INFO] running `Command { std: "docker" "start" "-a" "7440a0641f6c5b9a914c4814ea32fec5f5acf2975abe85401912ac1478ff06ae", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7440a0641f6c5b9a914c4814ea32fec5f5acf2975abe85401912ac1478ff06ae", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7440a0641f6c5b9a914c4814ea32fec5f5acf2975abe85401912ac1478ff06ae", kill_on_drop: false }`
[INFO] [stdout] 7440a0641f6c5b9a914c4814ea32fec5f5acf2975abe85401912ac1478ff06ae
[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=warn" "-e" "RUSTDOCFLAGS=--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:5ff2268d62e97bff2cde7d5815dd6ed5b47097566f13b8d0ca110b04b60e07ed" "/opt/rustwide/cargo-home/bin/cargo" "+1.69.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0414ca9ae2b0214f10841fb5e5634e4208f4bf5e5b6cec41f87505f3c4b78cc0
[INFO] running `Command { std: "docker" "start" "-a" "0414ca9ae2b0214f10841fb5e5634e4208f4bf5e5b6cec41f87505f3c4b78cc0", kill_on_drop: false }`
[INFO] [stderr]    Compiling cc v1.0.79
[INFO] [stderr]    Compiling ffi-opaque v2.0.1
[INFO] [stderr]    Compiling db-key v0.0.5
[INFO] [stderr]    Compiling num_cpus v1.15.0
[INFO] [stderr]    Compiling cmake v0.1.50
[INFO] [stderr]    Compiling leveldb-sys v2.0.9
[INFO] [stderr]    Compiling leveldb v0.8.6 (/opt/rustwide/workdir)
[INFO] [stdout] warning: `#[inline]` is ignored on function prototypes
[INFO] [stdout]    --> src/database/iterator.rs:113:5
[INFO] [stdout]     |
[INFO] [stdout] 113 |     #[inline]
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_attributes)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[inline]` is ignored on function prototypes
[INFO] [stdout]    --> src/database/iterator.rs:116:5
[INFO] [stdout]     |
[INFO] [stdout] 116 |     #[inline]
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[inline]` is ignored on function prototypes
[INFO] [stdout]    --> src/database/iterator.rs:119:5
[INFO] [stdout]     |
[INFO] [stdout] 119 |     #[inline]
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/database/error.rs:45:32
[INFO] [stdout]    |
[INFO] [stdout] 45 |     fn cause(&self) -> Option<&std::error::Error> {
[INFO] [stdout]    |                                ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 45 |     fn cause(&self) -> Option<&dyn std::error::Error> {
[INFO] [stdout]    |                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 11.34s
[INFO] running `Command { std: "docker" "inspect" "0414ca9ae2b0214f10841fb5e5634e4208f4bf5e5b6cec41f87505f3c4b78cc0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0414ca9ae2b0214f10841fb5e5634e4208f4bf5e5b6cec41f87505f3c4b78cc0", kill_on_drop: false }`
[INFO] [stdout] 0414ca9ae2b0214f10841fb5e5634e4208f4bf5e5b6cec41f87505f3c4b78cc0
[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=warn" "-e" "RUSTDOCFLAGS=--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:5ff2268d62e97bff2cde7d5815dd6ed5b47097566f13b8d0ca110b04b60e07ed" "/opt/rustwide/cargo-home/bin/cargo" "+1.69.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] be30f21060e688430fb000f25995080b525a968d4d7554e69efc8f81871e2c7e
[INFO] running `Command { std: "docker" "start" "-a" "be30f21060e688430fb000f25995080b525a968d4d7554e69efc8f81871e2c7e", kill_on_drop: false }`
[INFO] [stderr]    Compiling rand v0.4.6
[INFO] [stdout] warning: `#[inline]` is ignored on function prototypes
[INFO] [stdout]    --> src/database/iterator.rs:113:5
[INFO] [stdout]     |
[INFO] [stdout] 113 |     #[inline]
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_attributes)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[inline]` is ignored on function prototypes
[INFO] [stdout]    --> src/database/iterator.rs:116:5
[INFO] [stdout]     |
[INFO] [stdout] 116 |     #[inline]
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[inline]` is ignored on function prototypes
[INFO] [stdout]    --> src/database/iterator.rs:119:5
[INFO] [stdout]     |
[INFO] [stdout] 119 |     #[inline]
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/database/error.rs:45:32
[INFO] [stdout]    |
[INFO] [stdout] 45 |     fn cause(&self) -> Option<&std::error::Error> {
[INFO] [stdout]    |                                ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 45 |     fn cause(&self) -> Option<&dyn std::error::Error> {
[INFO] [stdout]    |                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling tempdir v0.3.7
[INFO] [stderr]    Compiling leveldb v0.8.6 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> tests/iterator.rs:84:22
[INFO] [stdout]    |
[INFO] [stdout] 84 |   let iterable: &mut Iterable<i32> = database;
[INFO] [stdout]    |                      ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 84 |   let iterable: &mut dyn Iterable<i32> = database;
[INFO] [stdout]    |                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[inline]` is ignored on function prototypes
[INFO] [stdout]    --> src/database/iterator.rs:113:5
[INFO] [stdout]     |
[INFO] [stdout] 113 |     #[inline]
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_attributes)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> tests/iterator.rs:99:22
[INFO] [stdout]    |
[INFO] [stdout] 99 |   let iterable: &mut Iterable<i32> = database;
[INFO] [stdout]    |                      ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 99 |   let iterable: &mut dyn Iterable<i32> = database;
[INFO] [stdout]    |                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[inline]` is ignored on function prototypes
[INFO] [stdout]    --> src/database/iterator.rs:116:5
[INFO] [stdout]     |
[INFO] [stdout] 116 |     #[inline]
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[inline]` is ignored on function prototypes
[INFO] [stdout]    --> src/database/iterator.rs:119:5
[INFO] [stdout]     |
[INFO] [stdout] 119 |     #[inline]
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/database/error.rs:45:32
[INFO] [stdout]    |
[INFO] [stdout] 45 |     fn cause(&self) -> Option<&std::error::Error> {
[INFO] [stdout]    |                                ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 45 |     fn cause(&self) -> Option<&dyn std::error::Error> {
[INFO] [stdout]    |                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `collect` that must be used
[INFO] [stdout]   --> tests/concurrent_access.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 17 | /     (0..10).map(|i| {
[INFO] [stdout] 18 | |          let local_db = shared.clone();
[INFO] [stdout] 19 | |
[INFO] [stdout] 20 | |          thread::spawn(move || {
[INFO] [stdout] ...  |
[INFO] [stdout] 28 | |     .map(JoinHandle::join)
[INFO] [stdout] 29 | |     .collect::<Vec<_>>();
[INFO] [stdout]    | |________________________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: if you really need to exhaust the iterator, consider `.for_each(drop)` instead
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 1.22s
[INFO] running `Command { std: "docker" "inspect" "be30f21060e688430fb000f25995080b525a968d4d7554e69efc8f81871e2c7e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "be30f21060e688430fb000f25995080b525a968d4d7554e69efc8f81871e2c7e", kill_on_drop: false }`
[INFO] [stdout] be30f21060e688430fb000f25995080b525a968d4d7554e69efc8f81871e2c7e
[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=warn" "-e" "RUSTDOCFLAGS=--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:5ff2268d62e97bff2cde7d5815dd6ed5b47097566f13b8d0ca110b04b60e07ed" "/opt/rustwide/cargo-home/bin/cargo" "+1.69.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 762aefe4565942cda2cdb2f88522d57ad4e0b89f0972d3f07c83a6d2e2307812
[INFO] running `Command { std: "docker" "start" "-a" "762aefe4565942cda2cdb2f88522d57ad4e0b89f0972d3f07c83a6d2e2307812", kill_on_drop: false }`
[INFO] [stderr] warning: `#[inline]` is ignored on function prototypes
[INFO] [stderr]    --> src/database/iterator.rs:113:5
[INFO] [stderr]     |
[INFO] [stderr] 113 |     #[inline]
[INFO] [stderr]     |     ^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_attributes)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `#[inline]` is ignored on function prototypes
[INFO] [stderr]    --> src/database/iterator.rs:116:5
[INFO] [stderr]     |
[INFO] [stderr] 116 |     #[inline]
[INFO] [stderr]     |     ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: `#[inline]` is ignored on function prototypes
[INFO] [stderr]    --> src/database/iterator.rs:119:5
[INFO] [stderr]     |
[INFO] [stderr] 119 |     #[inline]
[INFO] [stderr]     |     ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/database/error.rs:45:32
[INFO] [stderr]    |
[INFO] [stderr] 45 |     fn cause(&self) -> Option<&std::error::Error> {
[INFO] [stderr]    |                                ^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]    |
[INFO] [stderr] 45 |     fn cause(&self) -> Option<&dyn std::error::Error> {
[INFO] [stderr]    |                                +++
[INFO] [stderr] 
[INFO] [stderr] warning: `leveldb` (lib) generated 4 warnings (run `cargo fix --lib -p leveldb` to apply 1 suggestion)
[INFO] [stderr] warning: `leveldb` (lib test) generated 4 warnings (4 duplicates)
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> tests/iterator.rs:84:22
[INFO] [stderr]    |
[INFO] [stderr] 84 |   let iterable: &mut Iterable<i32> = database;
[INFO] [stderr]    |                      ^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]    |
[INFO] [stderr] 84 |   let iterable: &mut dyn Iterable<i32> = database;
[INFO] [stderr]    |                      +++
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> tests/iterator.rs:99:22
[INFO] [stderr]    |
[INFO] [stderr] 99 |   let iterable: &mut Iterable<i32> = database;
[INFO] [stderr]    |                      ^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: use `dyn`
[INFO] [stderr]    |
[INFO] [stderr] 99 |   let iterable: &mut dyn Iterable<i32> = database;
[INFO] [stderr]    |                      +++
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `collect` that must be used
[INFO] [stderr]   --> tests/concurrent_access.rs:17:5
[INFO] [stderr]    |
[INFO] [stderr] 17 | /     (0..10).map(|i| {
[INFO] [stderr] 18 | |          let local_db = shared.clone();
[INFO] [stderr] 19 | |
[INFO] [stderr] 20 | |          thread::spawn(move || {
[INFO] [stderr] ...  |
[INFO] [stderr] 28 | |     .map(JoinHandle::join)
[INFO] [stderr] 29 | |     .collect::<Vec<_>>();
[INFO] [stderr]    | |________________________^
[INFO] [stderr]    |
[INFO] [stderr]    = note: if you really need to exhaust the iterator, consider `.for_each(drop)` instead
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `leveldb` (test "tests") generated 3 warnings (run `cargo fix --test "tests"` to apply 2 suggestions)
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running unittests src/lib.rs (/opt/rustwide/target/debug/deps/leveldb-4feeafb30fa363fe)
[INFO] [stdout] 
[INFO] [stderr]      Running tests/tests.rs (/opt/rustwide/target/debug/deps/tests-1628993e7abfc780)
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] running 24 tests
[INFO] [stdout] test binary::test_write_to_database ... ok
[INFO] [stdout] test comparator::comparator::test_ord_comparator ... ok
[INFO] [stdout] test binary::test_delete_from_database ... ok
[INFO] [stdout] test database::test_create_options ... ok
[INFO] [stdout] test database::test_open_non_existant_database_without_create ... ok
[INFO] [stdout] test binary::test_get_from_filled_database ... ok
[INFO] [stdout] test cache::test_open_database_with_cache ... ok
[INFO] [stdout] test binary::test_get_from_empty_database ... ok
[INFO] [stdout] test compaction::compaction::test_iterator_from_to ... ok
[INFO] [stdout] test comparator::comparator::test_comparator ... ok
[INFO] [stdout] test database::test_open_database ... ok
[INFO] [stdout] test iterator::test_iterator ... ok
[INFO] [stdout] test concurrent_access::access_from_threads ... ok
[INFO] [stdout] test iterator::test_key_iterator ... ok
[INFO] [stdout] test iterator::test_iterator_from_to ... ok
[INFO] [stdout] test iterator::test_value_iterator ... ok
[INFO] [stdout] test iterator::test_iterator_last ... ok
[INFO] [stdout] test management::test_destroy_database ... ok
[INFO] [stdout] test management::test_repair_database ... ok
[INFO] [stdout] test iterator::test_iterator_reverse ... ok
[INFO] [stdout] test snapshots::test_snapshot_iterator ... ok
[INFO] [stdout] test snapshots::test_snapshots ... ok
[INFO] [stdout] test writebatch::test_writebatchiter ... ok
[INFO] [stdout] test writebatch::test_writebatch ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 24 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.09s
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests leveldb
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stdout] test src/lib.rs - (line 5) ... ignored
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 1 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "762aefe4565942cda2cdb2f88522d57ad4e0b89f0972d3f07c83a6d2e2307812", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "762aefe4565942cda2cdb2f88522d57ad4e0b89f0972d3f07c83a6d2e2307812", kill_on_drop: false }`
[INFO] [stdout] 762aefe4565942cda2cdb2f88522d57ad4e0b89f0972d3f07c83a6d2e2307812
