[INFO] fetching crate flashbang 0.1.0-prealpha...
[INFO] testing flashbang-0.1.0-prealpha against try#c2e32f1c9652b13ed99608599c1e855462f421f3 for pr-146098-7
[INFO] extracting crate flashbang 0.1.0-prealpha into /workspace/builds/worker-7-tc2/source
[INFO] started tweaking crates.io crate flashbang 0.1.0-prealpha
[INFO] finished tweaking crates.io crate flashbang 0.1.0-prealpha
[INFO] tweaked toml for crates.io crate flashbang 0.1.0-prealpha written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate flashbang 0.1.0-prealpha on toolchain c2e32f1c9652b13ed99608599c1e855462f421f3
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate flashbang 0.1.0-prealpha 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" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a1ffd57292aed06ae3b7f4c41a1166d7ae5f50e89ee4b4665cada43c7069c061
[INFO] running `Command { std: "docker" "start" "-a" "a1ffd57292aed06ae3b7f4c41a1166d7ae5f50e89ee4b4665cada43c7069c061", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a1ffd57292aed06ae3b7f4c41a1166d7ae5f50e89ee4b4665cada43c7069c061", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a1ffd57292aed06ae3b7f4c41a1166d7ae5f50e89ee4b4665cada43c7069c061", kill_on_drop: false }`
[INFO] [stdout] a1ffd57292aed06ae3b7f4c41a1166d7ae5f50e89ee4b4665cada43c7069c061
[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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6f54d2cb781ac3d8f69950723341096070025ee9d0ae27758cf259540a35b82e
[INFO] running `Command { std: "docker" "start" "-a" "6f54d2cb781ac3d8f69950723341096070025ee9d0ae27758cf259540a35b82e", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.139
[INFO] [stderr]    Compiling proc-macro2 v1.0.50
[INFO] [stderr]    Compiling quote v1.0.23
[INFO] [stderr]    Compiling syn v1.0.107
[INFO] [stderr]    Compiling futures-core v0.3.26
[INFO] [stderr]    Compiling subtle v2.4.1
[INFO] [stderr]    Compiling futures-channel v0.3.26
[INFO] [stderr]    Compiling futures-task v0.3.26
[INFO] [stderr]    Compiling digest v0.10.6
[INFO] [stderr]    Compiling futures-sink v0.3.26
[INFO] [stderr]    Compiling futures-util v0.3.26
[INFO] [stderr]    Compiling parking_lot_core v0.9.6
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]    Compiling pin-project-lite v0.2.9
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/proc-macro2-1.0.50/src/lib.rs:92:30
[INFO] [stdout]    |
[INFO] [stdout] 92 |     feature(proc_macro_span, proc_macro_span_shrink)
[INFO] [stdout]    |                              ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling futures-io v0.3.26
[INFO] [stderr]    Compiling tokio v1.24.2
[INFO] [stderr]    Compiling cpufeatures v0.2.5
[INFO] [stderr]    Compiling async-trait v0.1.63
[INFO] [stderr]    Compiling crc32fast v1.3.2
[INFO] [stderr]    Compiling bytes v1.3.0
[INFO] [stdout] For more information about this error, try `rustc --explain E0635`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `proc-macro2` (lib) due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "6f54d2cb781ac3d8f69950723341096070025ee9d0ae27758cf259540a35b82e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6f54d2cb781ac3d8f69950723341096070025ee9d0ae27758cf259540a35b82e", kill_on_drop: false }`
[INFO] [stdout] 6f54d2cb781ac3d8f69950723341096070025ee9d0ae27758cf259540a35b82e