[INFO] fetching crate skyway-webrtc-gateway-caller 0.2.1...
[INFO] building skyway-webrtc-gateway-caller-0.2.1 against master#ad85bc524b1ad696e42061ad8338d382dffbdbe5 for pr-146237-1
[INFO] extracting crate skyway-webrtc-gateway-caller 0.2.1 into /workspace/builds/worker-0-tc1/source
[INFO] started tweaking crates.io crate skyway-webrtc-gateway-caller 0.2.1
[INFO] removed 0 missing examples
[INFO] finished tweaking crates.io crate skyway-webrtc-gateway-caller 0.2.1
[INFO] tweaked toml for crates.io crate skyway-webrtc-gateway-caller 0.2.1 written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate skyway-webrtc-gateway-caller 0.2.1 on toolchain ad85bc524b1ad696e42061ad8338d382dffbdbe5
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ad85bc524b1ad696e42061ad8338d382dffbdbe5" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate skyway-webrtc-gateway-caller 0.2.1 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" "+ad85bc524b1ad696e42061ad8338d382dffbdbe5" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded similar v2.2.0
[INFO] [stderr]   Downloaded dotenv_codegen_implementation v0.15.0
[INFO] [stderr]   Downloaded dotenv_codegen v0.15.0
[INFO] [stderr]   Downloaded predicates-core v1.0.4
[INFO] [stderr]   Downloaded mockito v0.31.0
[INFO] [stderr]   Downloaded predicates-tree v1.0.6
[INFO] [stderr]   Downloaded mockall_derive v0.11.3
[INFO] [stderr]   Downloaded predicates v2.1.2
[INFO] [stderr]   Downloaded mockall v0.11.3
[INFO] [stderr]   Downloaded mockall_double v0.3.0
[INFO] [stderr]   Downloaded shaku v0.6.1
[INFO] [stderr]   Downloaded openssl-sys v0.9.77
[INFO] [stderr]   Downloaded shaku_derive v0.6.1
[INFO] [stderr]   Downloaded gimli v0.26.2
[INFO] [stderr]   Downloaded skyway-webrtc-gateway-api v0.2.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+ad85bc524b1ad696e42061ad8338d382dffbdbe5" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 89b08c020ad6ba7336138fcdd65a61e996a085feec234359390edd9b18394740
[INFO] running `Command { std: "docker" "start" "-a" "89b08c020ad6ba7336138fcdd65a61e996a085feec234359390edd9b18394740", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "89b08c020ad6ba7336138fcdd65a61e996a085feec234359390edd9b18394740", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "89b08c020ad6ba7336138fcdd65a61e996a085feec234359390edd9b18394740", kill_on_drop: false }`
[INFO] [stdout] 89b08c020ad6ba7336138fcdd65a61e996a085feec234359390edd9b18394740
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+ad85bc524b1ad696e42061ad8338d382dffbdbe5" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3217e14ad135c4fd60c43269327e7920e03a5adb82f5537685151e400e61399d
[INFO] running `Command { std: "docker" "start" "-a" "3217e14ad135c4fd60c43269327e7920e03a5adb82f5537685151e400e61399d", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.103
[INFO] [stderr]    Compiling cc v1.0.76
[INFO] [stderr]    Compiling futures-core v0.3.25
[INFO] [stderr]    Compiling proc-macro2 v1.0.47
[INFO] [stderr]    Compiling tokio v1.21.2
[INFO] [stderr]    Compiling futures-sink v0.3.25
[INFO] [stderr]    Compiling futures-task v0.3.25
[INFO] [stderr]    Compiling futures-channel v0.3.25
[INFO] [stderr]    Compiling futures-util v0.3.25
[INFO] [stderr]    Compiling itoa v1.0.4
[INFO] [stderr]    Compiling socket2 v0.4.7
[INFO] [stderr]    Compiling mio v0.8.5
[INFO] [stderr]    Compiling num_cpus v1.14.0
[INFO] [stderr]    Compiling parking_lot v0.12.1
[INFO] [stderr]    Compiling futures-io v0.3.25
[INFO] [stderr]    Compiling tracing-core v0.1.30
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/proc-macro2-1.0.47/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 native-tls v0.2.11
[INFO] [stderr]    Compiling serde v1.0.147
[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" "3217e14ad135c4fd60c43269327e7920e03a5adb82f5537685151e400e61399d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3217e14ad135c4fd60c43269327e7920e03a5adb82f5537685151e400e61399d", kill_on_drop: false }`
[INFO] [stdout] 3217e14ad135c4fd60c43269327e7920e03a5adb82f5537685151e400e61399d