[INFO] fetching crate label-macros 0.6.0...
[INFO] testing label-macros-0.6.0 against 1.90.0 for beta-1.91-3
[INFO] extracting crate label-macros 0.6.0 into /workspace/builds/worker-2-tc1/source
[INFO] started tweaking crates.io crate label-macros 0.6.0
[INFO] finished tweaking crates.io crate label-macros 0.6.0
[INFO] tweaked toml for crates.io crate label-macros 0.6.0 written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate label-macros 0.6.0 on toolchain 1.90.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 4 packages to latest compatible versions
[INFO] [stderr]       Adding syn v1.0.109 (available: v2.0.106)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 317e8598bad7a2d71eef368c34f2fae048fb5532feaf7f6a1d6008bb95266a36
[INFO] running `Command { std: "docker" "start" "-a" "317e8598bad7a2d71eef368c34f2fae048fb5532feaf7f6a1d6008bb95266a36", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "317e8598bad7a2d71eef368c34f2fae048fb5532feaf7f6a1d6008bb95266a36", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "317e8598bad7a2d71eef368c34f2fae048fb5532feaf7f6a1d6008bb95266a36", kill_on_drop: false }`
[INFO] [stdout] 317e8598bad7a2d71eef368c34f2fae048fb5532feaf7f6a1d6008bb95266a36
[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=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-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" "+1.90.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 76704d7792118566c59358d59ad5e4002bab29c2bae23f8e4d59f4be8374b5a0
[INFO] running `Command { std: "docker" "start" "-a" "76704d7792118566c59358d59ad5e4002bab29c2bae23f8e4d59f4be8374b5a0", kill_on_drop: false }`
[INFO] [stderr]    Compiling quote v1.0.41
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]    Compiling label-macros v0.6.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0432]: unresolved import `syn::export`
[INFO] [stdout]   --> src/lib.rs:14:10
[INFO] [stdout]    |
[INFO] [stdout] 14 | use syn::export::ToTokens;
[INFO] [stdout]    |          ^^^^^^ could not find `export` in `syn`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0433]: failed to resolve: could not find `export` in `syn`
[INFO] [stdout]   --> src/lib.rs:78:43
[INFO] [stdout]    |
[INFO] [stdout] 78 |     fn to_tokens(&self, tokens: &mut syn::export::TokenStream2) {
[INFO] [stdout]    |                                           ^^^^^^ could not find `export` in `syn`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(proc_macro_span)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0432, E0433, E0554.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0432`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `label-macros` (lib) due to 3 previous errors
[INFO] running `Command { std: "docker" "inspect" "76704d7792118566c59358d59ad5e4002bab29c2bae23f8e4d59f4be8374b5a0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "76704d7792118566c59358d59ad5e4002bab29c2bae23f8e4d59f4be8374b5a0", kill_on_drop: false }`
[INFO] [stdout] 76704d7792118566c59358d59ad5e4002bab29c2bae23f8e4d59f4be8374b5a0