[INFO] fetching crate semester 1.0.3...
[INFO] building semester-1.0.3 against try#4987e9d4227139400384ab59296ffee3b0fb1183 for pr-146237-2
[INFO] extracting crate semester 1.0.3 into /workspace/builds/worker-3-tc2/source
[INFO] started tweaking crates.io crate semester 1.0.3
[INFO] finished tweaking crates.io crate semester 1.0.3
[INFO] tweaked toml for crates.io crate semester 1.0.3 written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate semester 1.0.3 on toolchain 4987e9d4227139400384ab59296ffee3b0fb1183
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 10 packages to latest compatible versions
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 896ceee3f6ed5d6e817ca7809329cd50f2575f66e23e63b81799456b8e69cc07
[INFO] running `Command { std: "docker" "start" "-a" "896ceee3f6ed5d6e817ca7809329cd50f2575f66e23e63b81799456b8e69cc07", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "896ceee3f6ed5d6e817ca7809329cd50f2575f66e23e63b81799456b8e69cc07", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "896ceee3f6ed5d6e817ca7809329cd50f2575f66e23e63b81799456b8e69cc07", kill_on_drop: false }`
[INFO] [stdout] 896ceee3f6ed5d6e817ca7809329cd50f2575f66e23e63b81799456b8e69cc07
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/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" "RUSTDOCFLAGS=--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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 32d8e2dda81d4b7b8f66e5e37bac9c693bc2754c25668bbebdba20d499686dab
[INFO] running `Command { std: "docker" "start" "-a" "32d8e2dda81d4b7b8f66e5e37bac9c693bc2754c25668bbebdba20d499686dab", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.101
[INFO] [stderr]    Compiling unicode-ident v1.0.19
[INFO] [stderr]    Compiling quote v1.0.41
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]    Compiling either v1.15.0
[INFO] [stderr]    Compiling joinery v3.1.0
[INFO] [stderr]    Compiling itertools v0.10.5
[INFO] [stderr]    Compiling semester-macro v2.0.2
[INFO] [stderr]    Compiling semester v1.0.3 (/opt/rustwide/workdir)
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:290:5
[INFO] [stdout]     |
[INFO] [stdout] 290 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout]     = note: `#[warn(unused_attributes)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:297:5
[INFO] [stdout]     |
[INFO] [stdout] 297 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:303:5
[INFO] [stdout]     |
[INFO] [stdout] 303 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:309:5
[INFO] [stdout]     |
[INFO] [stdout] 309 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:346:5
[INFO] [stdout]     |
[INFO] [stdout] 346 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:352:5
[INFO] [stdout]     |
[INFO] [stdout] 352 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 6.59s
[INFO] running `Command { std: "docker" "inspect" "32d8e2dda81d4b7b8f66e5e37bac9c693bc2754c25668bbebdba20d499686dab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "32d8e2dda81d4b7b8f66e5e37bac9c693bc2754c25668bbebdba20d499686dab", kill_on_drop: false }`
[INFO] [stdout] 32d8e2dda81d4b7b8f66e5e37bac9c693bc2754c25668bbebdba20d499686dab
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/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" "RUSTDOCFLAGS=--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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d6c23f732ade5403c20e0b154bea5ecfbdba942f048f52c4ec747e3eeef10794
[INFO] running `Command { std: "docker" "start" "-a" "d6c23f732ade5403c20e0b154bea5ecfbdba942f048f52c4ec747e3eeef10794", kill_on_drop: false }`
[INFO] [stderr]    Compiling indent_write v2.2.0
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:290:5
[INFO] [stdout]     |
[INFO] [stdout] 290 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout]     = note: `#[warn(unused_attributes)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:297:5
[INFO] [stdout]     |
[INFO] [stdout] 297 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:303:5
[INFO] [stdout]     |
[INFO] [stdout] 303 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:309:5
[INFO] [stdout]     |
[INFO] [stdout] 309 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:346:5
[INFO] [stdout]     |
[INFO] [stdout] 346 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:352:5
[INFO] [stdout]     |
[INFO] [stdout] 352 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling cool_asserts v2.0.3
[INFO] [stderr]    Compiling semester v1.0.3 (/opt/rustwide/workdir)
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:290:5
[INFO] [stdout]     |
[INFO] [stdout] 290 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout]     = note: `#[warn(unused_attributes)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:297:5
[INFO] [stdout]     |
[INFO] [stdout] 297 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:303:5
[INFO] [stdout]     |
[INFO] [stdout] 303 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:309:5
[INFO] [stdout]     |
[INFO] [stdout] 309 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:346:5
[INFO] [stdout]     |
[INFO] [stdout] 346 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/lib.rs:352:5
[INFO] [stdout]     |
[INFO] [stdout] 352 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, functions, unions, required trait methods, provided trait methods, inherent methods, foreign functions, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 1.22s
[INFO] running `Command { std: "docker" "inspect" "d6c23f732ade5403c20e0b154bea5ecfbdba942f048f52c4ec747e3eeef10794", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d6c23f732ade5403c20e0b154bea5ecfbdba942f048f52c4ec747e3eeef10794", kill_on_drop: false }`
[INFO] [stdout] d6c23f732ade5403c20e0b154bea5ecfbdba942f048f52c4ec747e3eeef10794