[INFO] fetching crate violin 0.3.0...
[INFO] testing violin-0.3.0 against try#c2e32f1c9652b13ed99608599c1e855462f421f3 for pr-146098-8
[INFO] extracting crate violin 0.3.0 into /workspace/builds/worker-6-tc2/source
[INFO] started tweaking crates.io crate violin 0.3.0
[INFO] finished tweaking crates.io crate violin 0.3.0
[INFO] tweaked toml for crates.io crate violin 0.3.0 written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate violin 0.3.0 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 violin 0.3.0 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" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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] dfbe6b36376eaba562c4114e3d649428fa4315e749e9e980ca852ecf7403de3a
[INFO] running `Command { std: "docker" "start" "-a" "dfbe6b36376eaba562c4114e3d649428fa4315e749e9e980ca852ecf7403de3a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "dfbe6b36376eaba562c4114e3d649428fa4315e749e9e980ca852ecf7403de3a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dfbe6b36376eaba562c4114e3d649428fa4315e749e9e980ca852ecf7403de3a", kill_on_drop: false }`
[INFO] [stdout] dfbe6b36376eaba562c4114e3d649428fa4315e749e9e980ca852ecf7403de3a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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] 4c6906e8f26637d02628be84bd6f7341a01d7997c6c9656e9c55e46d80a9d82c
[INFO] running `Command { std: "docker" "start" "-a" "4c6906e8f26637d02628be84bd6f7341a01d7997c6c9656e9c55e46d80a9d82c", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.135
[INFO] [stderr]    Compiling ppv-lite86 v0.2.16
[INFO] [stderr]    Compiling getrandom v0.2.7
[INFO] [stderr]    Compiling rand_core v0.6.4
[INFO] [stderr]    Compiling rand_chacha v0.3.1
[INFO] [stderr]    Compiling rand v0.8.5
[INFO] [stderr]    Compiling violin v0.3.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.82s
[INFO] running `Command { std: "docker" "inspect" "4c6906e8f26637d02628be84bd6f7341a01d7997c6c9656e9c55e46d80a9d82c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4c6906e8f26637d02628be84bd6f7341a01d7997c6c9656e9c55e46d80a9d82c", kill_on_drop: false }`
[INFO] [stdout] 4c6906e8f26637d02628be84bd6f7341a01d7997c6c9656e9c55e46d80a9d82c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d06178c03cbe0b8f481f8e1705079e4e1497692a2370db08bad0a219112533bc
[INFO] running `Command { std: "docker" "start" "-a" "d06178c03cbe0b8f481f8e1705079e4e1497692a2370db08bad0a219112533bc", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling libc v0.2.135
[INFO] [stderr]    Compiling proc-macro2 v1.0.46
[INFO] [stderr]    Compiling unicode-ident v1.0.5
[INFO] [stderr]    Compiling quote v1.0.21
[INFO] [stderr]    Compiling syn v1.0.102
[INFO] [stderr]    Compiling crossbeam-utils v0.8.12
[INFO] [stderr]    Compiling serde_derive v1.0.145
[INFO] [stderr]    Compiling serde v1.0.145
[INFO] [stderr]    Compiling rayon-core v1.9.3
[INFO] [stderr]    Compiling scopeguard v1.1.0
[INFO] [stderr]    Compiling either v1.8.0
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/proc-macro2-1.0.46/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 serde_json v1.0.86
[INFO] [stderr]    Compiling os_str_bytes v6.3.0
[INFO] [stderr]    Compiling half v1.8.2
[INFO] [stderr]    Compiling ciborium-io v0.2.0
[INFO] [stderr]    Compiling plotters-backend v0.3.4
[INFO] [stderr]    Compiling memoffset v0.6.5
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.11
[INFO] [stderr]    Compiling num-traits v0.2.15
[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" "d06178c03cbe0b8f481f8e1705079e4e1497692a2370db08bad0a219112533bc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d06178c03cbe0b8f481f8e1705079e4e1497692a2370db08bad0a219112533bc", kill_on_drop: false }`
[INFO] [stdout] d06178c03cbe0b8f481f8e1705079e4e1497692a2370db08bad0a219112533bc