[INFO] fetching crate source-span 2.7.0...
[INFO] building source-span-2.7.0 against master#11663cd3bfefef7d34e8f0892c250bf698049392+rustflags=-Dtail-expr-drop-order for pr-134523
[INFO] extracting crate source-span 2.7.0 into /workspace/builds/worker-2-tc1/source
[INFO] validating manifest of crates.io crate source-span 2.7.0 on toolchain 11663cd3bfefef7d34e8f0892c250bf698049392
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate source-span 2.7.0
[INFO] finished tweaking crates.io crate source-span 2.7.0
[INFO] tweaked toml for crates.io crate source-span 2.7.0 written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] crate crates.io crate source-span 2.7.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6f340df9c0ac0a0cc22949929f7a32717c9cfef2e30a8ff6fe7191c60c3fb00f
[INFO] running `Command { std: "docker" "start" "-a" "6f340df9c0ac0a0cc22949929f7a32717c9cfef2e30a8ff6fe7191c60c3fb00f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6f340df9c0ac0a0cc22949929f7a32717c9cfef2e30a8ff6fe7191c60c3fb00f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6f340df9c0ac0a0cc22949929f7a32717c9cfef2e30a8ff6fe7191c60c3fb00f", kill_on_drop: false }`
[INFO] [stdout] 6f340df9c0ac0a0cc22949929f7a32717c9cfef2e30a8ff6fe7191c60c3fb00f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2a4d0544ff790b618d95004467dca06628fe72fbc5ef4e7c1bbce12e9f7ba68b
[INFO] running `Command { std: "docker" "start" "-a" "2a4d0544ff790b618d95004467dca06628fe72fbc5ef4e7c1bbce12e9f7ba68b", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.94
[INFO] [stderr]    Compiling numtoa v0.1.0
[INFO] [stderr]    Compiling termion v1.5.6
[INFO] [stderr]    Compiling source-span v2.7.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.95s
[INFO] running `Command { std: "docker" "inspect" "2a4d0544ff790b618d95004467dca06628fe72fbc5ef4e7c1bbce12e9f7ba68b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2a4d0544ff790b618d95004467dca06628fe72fbc5ef4e7c1bbce12e9f7ba68b", kill_on_drop: false }`
[INFO] [stdout] 2a4d0544ff790b618d95004467dca06628fe72fbc5ef4e7c1bbce12e9f7ba68b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] eb54a8b4b884a16128c34a29acf50a1fede377406f3095795bc9c92da83f8bf2
[INFO] running `Command { std: "docker" "start" "-a" "eb54a8b4b884a16128c34a29acf50a1fede377406f3095795bc9c92da83f8bf2", kill_on_drop: false }`
[INFO] [stderr]    Compiling utf8-decode v1.0.1
[INFO] [stderr]    Compiling source-span v2.7.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: fields `string` and `span` are never read
[INFO] [stdout]  --> examples/formatting_challenge.rs:8:2
[INFO] [stdout]   |
[INFO] [stdout] 7 | pub struct Token {
[INFO] [stdout]   |            ----- fields in this struct
[INFO] [stdout] 8 |     string: String,
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout] 9 |     span: Span,
[INFO] [stdout]   |     ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `Token` has a derived impl for the trait `Clone`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.40s
[INFO] running `Command { std: "docker" "inspect" "eb54a8b4b884a16128c34a29acf50a1fede377406f3095795bc9c92da83f8bf2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "eb54a8b4b884a16128c34a29acf50a1fede377406f3095795bc9c92da83f8bf2", kill_on_drop: false }`
[INFO] [stdout] eb54a8b4b884a16128c34a29acf50a1fede377406f3095795bc9c92da83f8bf2