[INFO] fetching crate pycall 0.3.0...
[INFO] testing pycall-0.3.0 against 1.49.0 for beta-1.50-1
[INFO] extracting crate pycall 0.3.0 into /workspace/builds/worker-1/source
[INFO] validating manifest of crates.io crate pycall 0.3.0 on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate pycall 0.3.0
[INFO] finished tweaking crates.io crate pycall 0.3.0
[INFO] tweaked toml for crates.io crate pycall 0.3.0 written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] crate crates.io crate pycall 0.3.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2b40050365e6c48f9ed70fdb2aab344d832e71d091d7176ae5abc454dce144c3
[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" "2b40050365e6c48f9ed70fdb2aab344d832e71d091d7176ae5abc454dce144c3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2b40050365e6c48f9ed70fdb2aab344d832e71d091d7176ae5abc454dce144c3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2b40050365e6c48f9ed70fdb2aab344d832e71d091d7176ae5abc454dce144c3", kill_on_drop: false }`
[INFO] [stdout] 2b40050365e6c48f9ed70fdb2aab344d832e71d091d7176ae5abc454dce144c3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--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] 7962f75927801d13217b23a4bf37b1bf85b6bd32b1dcf760cf30213970986b85
[INFO] running `Command { std: "docker" "start" "-a" "7962f75927801d13217b23a4bf37b1bf85b6bd32b1dcf760cf30213970986b85", kill_on_drop: false }`
[INFO] [stderr]    Compiling tempfile v3.1.0
[INFO] [stderr]    Compiling pycall v0.3.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/lib.rs:134:13
[INFO] [stdout]     |
[INFO] [stdout] 134 |             handle.join();
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/lib.rs:379:9
[INFO] [stdout]     |
[INFO] [stdout] 379 | /         writeln!(
[INFO] [stdout] 380 | |             &program.file,
[INFO] [stdout] 381 | |             "plt.plot({}, {}, {})",
[INFO] [stdout] 382 | |             PythonLiteral(x),
[INFO] [stdout] 383 | |             PythonLiteral(y),
[INFO] [stdout] 384 | |             PythonLiteral(args)
[INFO] [stdout] 385 | |         );
[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]    --> src/lib.rs:395:9
[INFO] [stdout]     |
[INFO] [stdout] 395 | /         writeln!(
[INFO] [stdout] 396 | |             &program.file,
[INFO] [stdout] 397 | |             "plt.plot({}, {})",
[INFO] [stdout] 398 | |             PythonLiteral(x),
[INFO] [stdout] 399 | |             PythonLiteral(y),
[INFO] [stdout] 400 | |         );
[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]    --> src/lib.rs:407:9
[INFO] [stdout]     |
[INFO] [stdout] 407 |         writeln!(&program.file, "plt.plot({})", PythonLiteral(y));
[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 3.14s
[INFO] running `Command { std: "docker" "inspect" "7962f75927801d13217b23a4bf37b1bf85b6bd32b1dcf760cf30213970986b85", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7962f75927801d13217b23a4bf37b1bf85b6bd32b1dcf760cf30213970986b85", kill_on_drop: false }`
[INFO] [stdout] 7962f75927801d13217b23a4bf37b1bf85b6bd32b1dcf760cf30213970986b85
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f240b91920baf866525faf25e8bdc7f3e5a93afa7a697a90628741875455aa3f
[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" "f240b91920baf866525faf25e8bdc7f3e5a93afa7a697a90628741875455aa3f", kill_on_drop: false }`
[INFO] [stderr]    Compiling pycall v0.3.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/lib.rs:134:13
[INFO] [stdout]     |
[INFO] [stdout] 134 |             handle.join();
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/lib.rs:379:9
[INFO] [stdout]     |
[INFO] [stdout] 379 | /         writeln!(
[INFO] [stdout] 380 | |             &program.file,
[INFO] [stdout] 381 | |             "plt.plot({}, {}, {})",
[INFO] [stdout] 382 | |             PythonLiteral(x),
[INFO] [stdout] 383 | |             PythonLiteral(y),
[INFO] [stdout] 384 | |             PythonLiteral(args)
[INFO] [stdout] 385 | |         );
[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]    --> src/lib.rs:395:9
[INFO] [stdout]     |
[INFO] [stdout] 395 | /         writeln!(
[INFO] [stdout] 396 | |             &program.file,
[INFO] [stdout] 397 | |             "plt.plot({}, {})",
[INFO] [stdout] 398 | |             PythonLiteral(x),
[INFO] [stdout] 399 | |             PythonLiteral(y),
[INFO] [stdout] 400 | |         );
[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]    --> src/lib.rs:407:9
[INFO] [stdout]     |
[INFO] [stdout] 407 |         writeln!(&program.file, "plt.plot({})", PythonLiteral(y));
[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] [stdout] warning: unused import: `pycall::MatPlotLib`
[INFO] [stdout]  --> examples/save.rs:2:9
[INFO] [stdout]   |
[INFO] [stdout] 2 |     use pycall::MatPlotLib;
[INFO] [stdout]   |         ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0425]: cannot find function `quick_plot` in this scope
[INFO] [stdout]    --> src/lib.rs:427:38
[INFO] [stdout]     |
[INFO] [stdout] 427 |     let join = std::thread::spawn(|| quick_plot(&(-50..50).map(|x| (-x * x)).collect::<Vec<_>>()));
[INFO] [stdout]     |                                      ^^^^^^^^^^ not found in this scope
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> examples/save.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 10 |     program.save_as("saved.py");
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> examples/main.rs:19:5
[INFO] [stdout]    |
[INFO] [stdout] 19 |     handles.0.join();
[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] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> examples/main.rs:20:5
[INFO] [stdout]    |
[INFO] [stdout] 20 |     handles.1.join();
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> examples/main.rs:21:5
[INFO] [stdout]    |
[INFO] [stdout] 21 |     handles.2.join();
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0425`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `pycall`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "f240b91920baf866525faf25e8bdc7f3e5a93afa7a697a90628741875455aa3f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f240b91920baf866525faf25e8bdc7f3e5a93afa7a697a90628741875455aa3f", kill_on_drop: false }`
[INFO] [stdout] f240b91920baf866525faf25e8bdc7f3e5a93afa7a697a90628741875455aa3f