[INFO] fetching crate tnetstring 0.2.0...
[INFO] testing tnetstring-0.2.0 against 1.47.0 for beta-1.48-1
[INFO] extracting crate tnetstring 0.2.0 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate tnetstring 0.2.0 on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate tnetstring 0.2.0
[INFO] finished tweaking crates.io crate tnetstring 0.2.0
[INFO] tweaked toml for crates.io crate tnetstring 0.2.0 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d95d8a14ad22efbb3d5aaf5b1c6b18064e69d7571d03a042302b5af564454a78
[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" "d95d8a14ad22efbb3d5aaf5b1c6b18064e69d7571d03a042302b5af564454a78", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d95d8a14ad22efbb3d5aaf5b1c6b18064e69d7571d03a042302b5af564454a78", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d95d8a14ad22efbb3d5aaf5b1c6b18064e69d7571d03a042302b5af564454a78", kill_on_drop: false }`
[INFO] [stdout] d95d8a14ad22efbb3d5aaf5b1c6b18064e69d7571d03a042302b5af564454a78
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4ba26aa350f3c0f31202d8d5fb208d1fe1d730894ac270cb23a8b16d00fa06bc
[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" "4ba26aa350f3c0f31202d8d5fb208d1fe1d730894ac270cb23a8b16d00fa06bc", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.44
[INFO] [stderr]    Compiling serde_derive v1.0.117
[INFO] [stderr]    Compiling serde v1.0.117
[INFO] [stderr]    Compiling maplit v1.0.2
[INFO] [stderr]    Compiling tnetstring v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: use of deprecated associated function `std::error::Error::description`: use the Display impl or to_string()
[INFO] [stdout]   --> src/error.rs:50:29
[INFO] [stdout]    |
[INFO] [stdout] 50 |         formatter.write_str(std::error::Error::description(self))
[INFO] [stdout]    |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0283]: type annotations needed
[INFO] [stdout]   --> src/ser.rs:49:18
[INFO] [stdout]    |
[INFO] [stdout] 45 | /     serializer
[INFO] [stdout] 46 | |         .output
[INFO] [stdout] 47 | |         .last()
[INFO] [stdout]    | |_______________- this method call resolves to `std::option::Option<&T>`
[INFO] [stdout] 48 |           .ok_or(Error::StackProblem)
[INFO] [stdout] 49 |           .map(|x| String::from(x.as_ref()))
[INFO] [stdout]    |                    ^^^^^^^^^^^^ cannot infer type for struct `std::string::String`
[INFO] [stdout]    |
[INFO] [stdout]    = note: cannot satisfy `std::string::String: std::convert::From<&_>`
[INFO] [stdout]    = note: required by `std::convert::From::from`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0283`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `tnetstring`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "4ba26aa350f3c0f31202d8d5fb208d1fe1d730894ac270cb23a8b16d00fa06bc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4ba26aa350f3c0f31202d8d5fb208d1fe1d730894ac270cb23a8b16d00fa06bc", kill_on_drop: false }`
[INFO] [stdout] 4ba26aa350f3c0f31202d8d5fb208d1fe1d730894ac270cb23a8b16d00fa06bc
