[INFO] fetching crate mut_guard 0.1.0...
[INFO] checking mut_guard-0.1.0 against master#22572d0994593197593e2a1b7b18d720a9a349a7 for pr-126452-1
[INFO] extracting crate mut_guard 0.1.0 into /workspace/builds/worker-7-tc1/source
[INFO] validating manifest of crates.io crate mut_guard 0.1.0 on toolchain 22572d0994593197593e2a1b7b18d720a9a349a7
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+22572d0994593197593e2a1b7b18d720a9a349a7" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mut_guard 0.1.0
[INFO] finished tweaking crates.io crate mut_guard 0.1.0
[INFO] tweaked toml for crates.io crate mut_guard 0.1.0 written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+22572d0994593197593e2a1b7b18d720a9a349a7" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 11 packages to latest compatible versions
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+22572d0994593197593e2a1b7b18d720a9a349a7" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2021
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+22572d0994593197593e2a1b7b18d720a9a349a7" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7de38ea0d73328ecff4bbde8f2afb16f022b9d988b1e4a6753d925914965409f
[INFO] running `Command { std: "docker" "start" "-a" "7de38ea0d73328ecff4bbde8f2afb16f022b9d988b1e4a6753d925914965409f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7de38ea0d73328ecff4bbde8f2afb16f022b9d988b1e4a6753d925914965409f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7de38ea0d73328ecff4bbde8f2afb16f022b9d988b1e4a6753d925914965409f", kill_on_drop: false }`
[INFO] [stdout] 7de38ea0d73328ecff4bbde8f2afb16f022b9d988b1e4a6753d925914965409f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+22572d0994593197593e2a1b7b18d720a9a349a7" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1c831df3dee31553b2f9f826968497f1f0716e7b51a6955ef3a4b012ae05e193
[INFO] running `Command { std: "docker" "start" "-a" "1c831df3dee31553b2f9f826968497f1f0716e7b51a6955ef3a4b012ae05e193", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2021
[INFO] [stderr]     Checking mut_guard v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]    Compiling serde v1.0.209
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/lib.rs:211:12
[INFO] [stdout]     |
[INFO] [stdout] 211 |     f: Box<'a + FnMut(&mut T)>,
[INFO] [stdout]     |            ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]     = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 211 |     f: Box<dyn 'a + FnMut(&mut T)>,
[INFO] [stdout]     |            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking serde_json v1.0.127
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/lib.rs:211:12
[INFO] [stdout]     |
[INFO] [stdout] 211 |     f: Box<'a + FnMut(&mut T)>,
[INFO] [stdout]     |            ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]     = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 211 |     f: Box<dyn 'a + FnMut(&mut T)>,
[INFO] [stdout]     |            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.98s
[INFO] running `Command { std: "docker" "inspect" "1c831df3dee31553b2f9f826968497f1f0716e7b51a6955ef3a4b012ae05e193", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1c831df3dee31553b2f9f826968497f1f0716e7b51a6955ef3a4b012ae05e193", kill_on_drop: false }`
[INFO] [stdout] 1c831df3dee31553b2f9f826968497f1f0716e7b51a6955ef3a4b012ae05e193
[INFO] checking mut_guard-0.1.0 against try#6289438dbad80b1a0029c66dd3f6abf57c2c51be for pr-126452-1
[INFO] extracting crate mut_guard 0.1.0 into /workspace/builds/worker-7-tc2/source
[INFO] validating manifest of crates.io crate mut_guard 0.1.0 on toolchain 6289438dbad80b1a0029c66dd3f6abf57c2c51be
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+6289438dbad80b1a0029c66dd3f6abf57c2c51be" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mut_guard 0.1.0
[INFO] finished tweaking crates.io crate mut_guard 0.1.0
[INFO] tweaked toml for crates.io crate mut_guard 0.1.0 written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+6289438dbad80b1a0029c66dd3f6abf57c2c51be" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 11 packages to latest compatible versions
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+6289438dbad80b1a0029c66dd3f6abf57c2c51be" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2021
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+6289438dbad80b1a0029c66dd3f6abf57c2c51be" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1e560375abc5dd854bb3749af02e8d7c8a504c85c5fc813d7405a423208a0d9d
[INFO] running `Command { std: "docker" "start" "-a" "1e560375abc5dd854bb3749af02e8d7c8a504c85c5fc813d7405a423208a0d9d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1e560375abc5dd854bb3749af02e8d7c8a504c85c5fc813d7405a423208a0d9d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1e560375abc5dd854bb3749af02e8d7c8a504c85c5fc813d7405a423208a0d9d", kill_on_drop: false }`
[INFO] [stdout] 1e560375abc5dd854bb3749af02e8d7c8a504c85c5fc813d7405a423208a0d9d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+6289438dbad80b1a0029c66dd3f6abf57c2c51be" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] dda72ccebf23e2155dc7d6037746af7dac2cc02b8b56c282c7242d339cd98a9a
[INFO] running `Command { std: "docker" "start" "-a" "dda72ccebf23e2155dc7d6037746af7dac2cc02b8b56c282c7242d339cd98a9a", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2021
[INFO] [stderr]     Checking mut_guard v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]    Compiling serde v1.0.209
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/lib.rs:211:12
[INFO] [stdout]     |
[INFO] [stdout] 211 |     f: Box<'a + FnMut(&mut T)>,
[INFO] [stdout]     |            ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]     = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 211 |     f: Box<dyn 'a + FnMut(&mut T)>,
[INFO] [stdout]     |            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking serde_json v1.0.127
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]    --> src/lib.rs:211:12
[INFO] [stdout]     |
[INFO] [stdout] 211 |     f: Box<'a + FnMut(&mut T)>,
[INFO] [stdout]     |            ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]     = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: if this is an object-safe trait, use `dyn`
[INFO] [stdout]     |
[INFO] [stdout] 211 |     f: Box<dyn 'a + FnMut(&mut T)>,
[INFO] [stdout]     |            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.63s
[INFO] running `Command { std: "docker" "inspect" "dda72ccebf23e2155dc7d6037746af7dac2cc02b8b56c282c7242d339cd98a9a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dda72ccebf23e2155dc7d6037746af7dac2cc02b8b56c282c7242d339cd98a9a", kill_on_drop: false }`
[INFO] [stdout] dda72ccebf23e2155dc7d6037746af7dac2cc02b8b56c282c7242d339cd98a9a