[INFO] fetching crate puffin-imgui 0.22.0...
[INFO] testing puffin-imgui-0.22.0 against try#2440211fe03bc45c89b6dc1a3df18382ce91e32b for pr-146098-1
[INFO] extracting crate puffin-imgui 0.22.0 into /workspace/builds/worker-1-tc2/source
[INFO] started tweaking crates.io crate puffin-imgui 0.22.0
[INFO] finished tweaking crates.io crate puffin-imgui 0.22.0
[INFO] tweaked toml for crates.io crate puffin-imgui 0.22.0 written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate puffin-imgui 0.22.0 on toolchain 2440211fe03bc45c89b6dc1a3df18382ce91e32b
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+2440211fe03bc45c89b6dc1a3df18382ce91e32b" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate puffin-imgui 0.22.0 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" "+2440211fe03bc45c89b6dc1a3df18382ce91e32b" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+2440211fe03bc45c89b6dc1a3df18382ce91e32b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 588c683e2101988b0f8730867449f9ef9545f8dc0a5ce9c97002d92e0d8032ec
[INFO] running `Command { std: "docker" "start" "-a" "588c683e2101988b0f8730867449f9ef9545f8dc0a5ce9c97002d92e0d8032ec", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "588c683e2101988b0f8730867449f9ef9545f8dc0a5ce9c97002d92e0d8032ec", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "588c683e2101988b0f8730867449f9ef9545f8dc0a5ce9c97002d92e0d8032ec", kill_on_drop: false }`
[INFO] [stdout] 588c683e2101988b0f8730867449f9ef9545f8dc0a5ce9c97002d92e0d8032ec
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+2440211fe03bc45c89b6dc1a3df18382ce91e32b" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c16465d6c8e11634fa69bae4bcce2ad77b84e6879999fb6eb8803434ad5eaeb7
[INFO] running `Command { std: "docker" "start" "-a" "c16465d6c8e11634fa69bae4bcce2ad77b84e6879999fb6eb8803434ad5eaeb7", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.58
[INFO] [stderr]    Compiling unicode-ident v1.0.6
[INFO] [stderr]    Compiling quote v1.0.27
[INFO] [stderr]    Compiling libc v0.2.144
[INFO] [stderr]    Compiling syn v1.0.107
[INFO] [stderr]    Compiling serde_derive v1.0.137
[INFO] [stderr]    Compiling parking_lot_core v0.9.3
[INFO] [stderr]    Compiling serde v1.0.137
[INFO] [stderr]    Compiling cc v1.0.73
[INFO] [stderr]    Compiling smallvec v1.8.0
[INFO] [stderr]    Compiling anyhow v1.0.57
[INFO] [stderr]    Compiling chlorine v1.0.10
[INFO] [stderr]    Compiling mint v0.5.9
[INFO] [stderr]    Compiling lock_api v0.4.7
[INFO] [stderr]    Compiling instant v0.1.12
[INFO] [stderr]    Compiling once_cell v1.13.1
[INFO] [stderr]    Compiling byteorder v1.4.3
[INFO] [stderr]    Compiling lz4_flex v0.10.0
[INFO] [stderr]    Compiling natord v1.0.9
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/proc-macro2-1.0.58/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 imgui-sys v0.10.0
[INFO] [stderr]    Compiling parking_lot v0.12.0
[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" "c16465d6c8e11634fa69bae4bcce2ad77b84e6879999fb6eb8803434ad5eaeb7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c16465d6c8e11634fa69bae4bcce2ad77b84e6879999fb6eb8803434ad5eaeb7", kill_on_drop: false }`
[INFO] [stdout] c16465d6c8e11634fa69bae4bcce2ad77b84e6879999fb6eb8803434ad5eaeb7