[INFO] fetching crate float_fast_print 0.1.2...
[INFO] checking float_fast_print-0.1.2 against try#55b3f428b4fac6790b1e8492e0b91ff2d80aec7c for pr-77035
[INFO] extracting crate float_fast_print 0.1.2 into /workspace/builds/worker-11/source
[INFO] validating manifest of crates.io crate float_fast_print 0.1.2 on toolchain 55b3f428b4fac6790b1e8492e0b91ff2d80aec7c
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+55b3f428b4fac6790b1e8492e0b91ff2d80aec7c" "read-manifest" "--manifest-path" "Cargo.toml", 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-11/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+55b3f428b4fac6790b1e8492e0b91ff2d80aec7c" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+55b3f428b4fac6790b1e8492e0b91ff2d80aec7c" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+55b3f428b4fac6790b1e8492e0b91ff2d80aec7c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 531ab3386fd0d5e860cf4110c0ff1558095c7bb9b635423f8f5b07c4ded64fdd
[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" "531ab3386fd0d5e860cf4110c0ff1558095c7bb9b635423f8f5b07c4ded64fdd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "531ab3386fd0d5e860cf4110c0ff1558095c7bb9b635423f8f5b07c4ded64fdd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "531ab3386fd0d5e860cf4110c0ff1558095c7bb9b635423f8f5b07c4ded64fdd", kill_on_drop: false }`
[INFO] [stdout] 531ab3386fd0d5e860cf4110c0ff1558095c7bb9b635423f8f5b07c4ded64fdd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "rustops/crates-build-env@sha256:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+55b3f428b4fac6790b1e8492e0b91ff2d80aec7c" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] db9f7cf74a2828b7c346e61c0e8ab932739c7aff49d4b65ff9541ab79622a9c6
[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" "db9f7cf74a2828b7c346e61c0e8ab932739c7aff49d4b65ff9541ab79622a9c6", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.81
[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 `std::result::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 a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::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 a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::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 a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::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 a macro (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 5.18s
[INFO] running `Command { std: "docker" "inspect" "db9f7cf74a2828b7c346e61c0e8ab932739c7aff49d4b65ff9541ab79622a9c6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "db9f7cf74a2828b7c346e61c0e8ab932739c7aff49d4b65ff9541ab79622a9c6", kill_on_drop: false }`
[INFO] [stdout] db9f7cf74a2828b7c346e61c0e8ab932739c7aff49d4b65ff9541ab79622a9c6