[INFO] fetching crate syntax-tree 0.3.2...
[INFO] checking syntax-tree-0.3.2 against try#cac44d9528e3bbbdaa1537d187bd489ccc5de18c for pr-91141
[INFO] extracting crate syntax-tree 0.3.2 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate syntax-tree 0.3.2 on toolchain cac44d9528e3bbbdaa1537d187bd489ccc5de18c
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate syntax-tree 0.3.2
[INFO] finished tweaking crates.io crate syntax-tree 0.3.2
[INFO] tweaked toml for crates.io crate syntax-tree 0.3.2 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3463b932cb3d1bb1e9e2a74b9f96af76cda49362dfa63c8be79a6595479d5609
[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" "3463b932cb3d1bb1e9e2a74b9f96af76cda49362dfa63c8be79a6595479d5609", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3463b932cb3d1bb1e9e2a74b9f96af76cda49362dfa63c8be79a6595479d5609", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3463b932cb3d1bb1e9e2a74b9f96af76cda49362dfa63c8be79a6595479d5609", kill_on_drop: false }`
[INFO] [stdout] 3463b932cb3d1bb1e9e2a74b9f96af76cda49362dfa63c8be79a6595479d5609
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+cac44d9528e3bbbdaa1537d187bd489ccc5de18c" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5c82c8f08f876efd67f70430b250ca503eff754cc37996fcae294459deca325f
[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" "5c82c8f08f876efd67f70430b250ca503eff754cc37996fcae294459deca325f", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking getrandom v0.2.3
[INFO] [stderr]     Checking uuid v0.8.2
[INFO] [stderr]     Checking syntax-tree v0.3.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]    --> src/node.rs:315:21
[INFO] [stdout]     |
[INFO] [stdout] 315 |                     &mut self.children.as_mut().unwrap().push(node);
[INFO] [stdout]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 315 |                     let _ = &mut self.children.as_mut().unwrap().push(node);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]    --> src/node.rs:318:21
[INFO] [stdout]     |
[INFO] [stdout] 318 |                     &mut self.children.as_mut().unwrap().insert(idx, node);
[INFO] [stdout]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]     |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 318 |                     let _ = &mut self.children.as_mut().unwrap().insert(idx, node);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]    --> src/node.rs:315:21
[INFO] [stdout]     |
[INFO] [stdout] 315 |                     &mut self.children.as_mut().unwrap().push(node);
[INFO] [stdout]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 315 |                     let _ = &mut self.children.as_mut().unwrap().push(node);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]    --> src/node.rs:318:21
[INFO] [stdout]     |
[INFO] [stdout] 318 |                     &mut self.children.as_mut().unwrap().insert(idx, node);
[INFO] [stdout]     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]     |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 318 |                     let _ = &mut self.children.as_mut().unwrap().insert(idx, node);
[INFO] [stdout]     |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 2.50s
[INFO] running `Command { std: "docker" "inspect" "5c82c8f08f876efd67f70430b250ca503eff754cc37996fcae294459deca325f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5c82c8f08f876efd67f70430b250ca503eff754cc37996fcae294459deca325f", kill_on_drop: false }`
[INFO] [stdout] 5c82c8f08f876efd67f70430b250ca503eff754cc37996fcae294459deca325f