[INFO] fetching crate error-iter 0.4.1...
[INFO] checking error-iter-0.4.1 against master#cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c for pr-143170
[INFO] extracting crate error-iter 0.4.1 into /workspace/builds/worker-4-tc1/source
[INFO] started tweaking crates.io crate error-iter 0.4.1
[INFO] finished tweaking crates.io crate error-iter 0.4.1
[INFO] tweaked toml for crates.io crate error-iter 0.4.1 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate error-iter 0.4.1 on toolchain cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate error-iter 0.4.1 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" "+cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded thiserror v1.0.39
[INFO] [stderr]   Downloaded thiserror-impl v1.0.39
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 45bde51decac202f62bcc9794710412bbe7d01623ff204e8199fb143c96249a1
[INFO] running `Command { std: "docker" "start" "-a" "45bde51decac202f62bcc9794710412bbe7d01623ff204e8199fb143c96249a1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "45bde51decac202f62bcc9794710412bbe7d01623ff204e8199fb143c96249a1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "45bde51decac202f62bcc9794710412bbe7d01623ff204e8199fb143c96249a1", kill_on_drop: false }`
[INFO] [stdout] 45bde51decac202f62bcc9794710412bbe7d01623ff204e8199fb143c96249a1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] bf5a561fc6e3a79f94e6895a3d1bcf53a96bcc0ef1687f47915bf4e2ea2f5557
[INFO] running `Command { std: "docker" "start" "-a" "bf5a561fc6e3a79f94e6895a3d1bcf53a96bcc0ef1687f47915bf4e2ea2f5557", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.52
[INFO] [stderr]    Compiling quote v1.0.26
[INFO] [stderr]    Compiling unicode-ident v1.0.8
[INFO] [stderr]    Compiling thiserror v1.0.39
[INFO] [stderr]     Checking error-iter v0.4.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: lifetime flowing from input to output with different syntax can be confusing
[INFO] [stdout]   --> src/lib.rs:76:16
[INFO] [stdout]    |
[INFO] [stdout] 76 |     fn sources(&self) -> ErrorIterator {
[INFO] [stdout]    |                ^^^^^     ------------- the lifetime gets resolved as `'_`
[INFO] [stdout]    |                |
[INFO] [stdout]    |                this lifetime flows to the output
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
[INFO] [stdout]    |
[INFO] [stdout] 76 |     fn sources(&self) -> ErrorIterator<'_> {
[INFO] [stdout]    |                                       ++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/proc-macro2-1.0.52/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] [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] running `Command { std: "docker" "inspect" "bf5a561fc6e3a79f94e6895a3d1bcf53a96bcc0ef1687f47915bf4e2ea2f5557", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bf5a561fc6e3a79f94e6895a3d1bcf53a96bcc0ef1687f47915bf4e2ea2f5557", kill_on_drop: false }`
[INFO] [stdout] bf5a561fc6e3a79f94e6895a3d1bcf53a96bcc0ef1687f47915bf4e2ea2f5557