[INFO] fetching crate float_fast_print 0.1.2...
[INFO] checking float_fast_print-0.1.2 against try#8de4b308b608cded0ebccf658a0fc719bce87d4e for pr-89056
[INFO] extracting crate float_fast_print 0.1.2 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate float_fast_print 0.1.2 on toolchain 8de4b308b608cded0ebccf658a0fc719bce87d4e
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate float_fast_print 0.1.2
[INFO] finished tweaking crates.io crate float_fast_print 0.1.2
[INFO] tweaked toml for crates.io crate float_fast_print 0.1.2 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 765b3bfd6aca0def6a269f951252d53341731c1a8a1b00742d8b34cfdbc7294f
[INFO] running `Command { std: "docker" "start" "-a" "765b3bfd6aca0def6a269f951252d53341731c1a8a1b00742d8b34cfdbc7294f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "765b3bfd6aca0def6a269f951252d53341731c1a8a1b00742d8b34cfdbc7294f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "765b3bfd6aca0def6a269f951252d53341731c1a8a1b00742d8b34cfdbc7294f", kill_on_drop: false }`
[INFO] [stdout] 765b3bfd6aca0def6a269f951252d53341731c1a8a1b00742d8b34cfdbc7294f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+8de4b308b608cded0ebccf658a0fc719bce87d4e" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 825e1f9af138d7f8ec1132529c3db7b0467fbe3e1d765da25040d5139b93b9eb
[INFO] running `Command { std: "docker" "start" "-a" "825e1f9af138d7f8ec1132529c3db7b0467fbe3e1d765da25040d5139b93b9eb", kill_on_drop: false }`
[INFO] [stderr]     Checking rand_core v0.4.2
[INFO] [stderr]     Checking float_fast_print v0.1.2 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr]     Checking rand v0.5.6
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> tests/benchmarks.rs:17:9
[INFO] [stdout]    |
[INFO] [stdout] 17 |         write!(&mut buffer, "{:?}", x);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: this warning originates in the macro `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> tests/benchmarks.rs:28:9
[INFO] [stdout]    |
[INFO] [stdout] 28 |         write!(&mut buffer, "{}", x);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: this warning originates in the macro `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> tests/benchmarks.rs:39:9
[INFO] [stdout]    |
[INFO] [stdout] 39 |         write!(&mut buffer, "{:?}", x);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: this warning originates in the macro `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> tests/benchmarks.rs:50:9
[INFO] [stdout]    |
[INFO] [stdout] 50 |         write!(&mut buffer, "{}", x);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: this warning originates in the macro `write` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.86s
[INFO] running `Command { std: "docker" "inspect" "825e1f9af138d7f8ec1132529c3db7b0467fbe3e1d765da25040d5139b93b9eb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "825e1f9af138d7f8ec1132529c3db7b0467fbe3e1d765da25040d5139b93b9eb", kill_on_drop: false }`
[INFO] [stdout] 825e1f9af138d7f8ec1132529c3db7b0467fbe3e1d765da25040d5139b93b9eb