[INFO] fetching crate maybe-serde 0.2.1...
[INFO] testing maybe-serde-0.2.1 against try#d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2 for pr-86479
[INFO] extracting crate maybe-serde 0.2.1 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate maybe-serde 0.2.1 on toolchain d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate maybe-serde 0.2.1
[INFO] finished tweaking crates.io crate maybe-serde 0.2.1
[INFO] tweaked toml for crates.io crate maybe-serde 0.2.1 written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d3922107ce4a9eb26a8fb2cbff7ff318b1b383e09eb5eb74a221e910c2b3866c
[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" "d3922107ce4a9eb26a8fb2cbff7ff318b1b383e09eb5eb74a221e910c2b3866c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d3922107ce4a9eb26a8fb2cbff7ff318b1b383e09eb5eb74a221e910c2b3866c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d3922107ce4a9eb26a8fb2cbff7ff318b1b383e09eb5eb74a221e910c2b3866c", kill_on_drop: false }`
[INFO] [stdout] d3922107ce4a9eb26a8fb2cbff7ff318b1b383e09eb5eb74a221e910c2b3866c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6f37e305b3106091689ba9d390bba75bcc71af98396cfff144fc60098150f4b8
[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" "6f37e305b3106091689ba9d390bba75bcc71af98396cfff144fc60098150f4b8", kill_on_drop: false }`
[INFO] [stderr]    Compiling maybe-serde v0.2.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(specialization)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout]   = help: consider using `min_specialization` instead, which is more stable and complete
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.19s
[INFO] running `Command { std: "docker" "inspect" "6f37e305b3106091689ba9d390bba75bcc71af98396cfff144fc60098150f4b8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6f37e305b3106091689ba9d390bba75bcc71af98396cfff144fc60098150f4b8", kill_on_drop: false }`
[INFO] [stdout] 6f37e305b3106091689ba9d390bba75bcc71af98396cfff144fc60098150f4b8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 986dd9779797b8e011c40a31abd0ef77bf82be664b044a53650bd466fd9daa64
[INFO] running `Command { std: "docker" "start" "-a" "986dd9779797b8e011c40a31abd0ef77bf82be664b044a53650bd466fd9daa64", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.74
[INFO] [stderr]    Compiling itoa v0.4.7
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(specialization)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout]   = help: consider using `min_specialization` instead, which is more stable and complete
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling serde_json v1.0.66
[INFO] [stderr]    Compiling serde_derive v1.0.127
[INFO] [stderr]    Compiling maybe-serde v0.2.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(specialization)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout]   = help: consider using `min_specialization` instead, which is more stable and complete
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 13.47s
[INFO] running `Command { std: "docker" "inspect" "986dd9779797b8e011c40a31abd0ef77bf82be664b044a53650bd466fd9daa64", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "986dd9779797b8e011c40a31abd0ef77bf82be664b044a53650bd466fd9daa64", kill_on_drop: false }`
[INFO] [stdout] 986dd9779797b8e011c40a31abd0ef77bf82be664b044a53650bd466fd9daa64
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+d2e9fff28e244f1ea4927194f1f9b77f93e2ffe2" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] ca47668cc196501795cb1784d16cc2de5dcf68fde4447062203b599f9fc03217
[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" "ca47668cc196501795cb1784d16cc2de5dcf68fde4447062203b599f9fc03217", kill_on_drop: false }`
[INFO] [stderr] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stderr]  --> src/lib.rs:1:12
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(specialization)]
[INFO] [stderr]   |            ^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(incomplete_features)]` on by default
[INFO] [stderr]   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stderr]   = help: consider using `min_specialization` instead, which is more stable and complete
[INFO] [stderr] 
[INFO] [stderr] warning: `maybe-serde` (lib) generated 1 warning
[INFO] [stderr] warning: `maybe-serde` (lib test) generated 1 warning (1 duplicate)
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/maybe_serde-ce4253413b593bab)
[INFO] [stdout] 
[INFO] [stdout] running 4 tests
[INFO] [stdout] test tests::serde_none ... ok
[INFO] [stdout] test tests::serde_none_maybe_serde ... ok
[INFO] [stdout] test tests::serde_some ... ok
[INFO] [stdout] test tests::serde_some_maybe_serde ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 4 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.01s
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests maybe-serde
[INFO] [stderr] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stderr]  --> /opt/rustwide/workdir/src/lib.rs:1:12
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![feature(specialization)]
[INFO] [stderr]   |            ^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(incomplete_features)]` on by default
[INFO] [stderr]   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stderr]   = help: consider using `min_specialization` instead, which is more stable and complete
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] [stdout] 
[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] running `Command { std: "docker" "inspect" "ca47668cc196501795cb1784d16cc2de5dcf68fde4447062203b599f9fc03217", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ca47668cc196501795cb1784d16cc2de5dcf68fde4447062203b599f9fc03217", kill_on_drop: false }`
[INFO] [stdout] ca47668cc196501795cb1784d16cc2de5dcf68fde4447062203b599f9fc03217