[INFO] cloning repository https://github.com/lffg2/rust-playground
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/lffg2/rust-playground" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flffg2%2Frust-playground", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flffg2%2Frust-playground'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] fba3506cb04d538400f4e09548d735e83330f505
[INFO] checking lffg2/rust-playground against master#af4a5a13a15fa0c60e06321077ef452f769b42fd for pr-122960-3
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flffg2%2Frust-playground" "/workspace/builds/worker-3-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/lffg2/rust-playground on toolchain af4a5a13a15fa0c60e06321077ef452f769b42fd
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+af4a5a13a15fa0c60e06321077ef452f769b42fd" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/lffg2/rust-playground
[INFO] finished tweaking git repo https://github.com/lffg2/rust-playground
[INFO] tweaked toml for git repo https://github.com/lffg2/rust-playground written to /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/lffg2/rust-playground 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" "+af4a5a13a15fa0c60e06321077ef452f769b42fd" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: virtual workspace defaulting to `resolver = "1"` despite one or more workspace members being on edition 2021 which implies `resolver = "2"`
[INFO] [stderr] note: to keep the current resolver, specify `workspace.resolver = "1"` in the workspace root's manifest
[INFO] [stderr] note: to use the edition 2021 resolver, specify `workspace.resolver = "2"` in the workspace root's manifest
[INFO] [stderr] note: for more details see https://doc.rust-lang.org/cargo/reference/resolver.html#resolver-versions
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+af4a5a13a15fa0c60e06321077ef452f769b42fd" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ab21a4a14e40a2d30f2b09698266c77287f590ef40d050ce6575f8909d07b4d5
[INFO] running `Command { std: "docker" "start" "-a" "ab21a4a14e40a2d30f2b09698266c77287f590ef40d050ce6575f8909d07b4d5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ab21a4a14e40a2d30f2b09698266c77287f590ef40d050ce6575f8909d07b4d5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ab21a4a14e40a2d30f2b09698266c77287f590ef40d050ce6575f8909d07b4d5", kill_on_drop: false }`
[INFO] [stdout] ab21a4a14e40a2d30f2b09698266c77287f590ef40d050ce6575f8909d07b4d5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+af4a5a13a15fa0c60e06321077ef452f769b42fd" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] eaa5625ee246832b9a1fd81281fa2075517ee7a799e94be358a2b5e41def16e5
[INFO] running `Command { std: "docker" "start" "-a" "eaa5625ee246832b9a1fd81281fa2075517ee7a799e94be358a2b5e41def16e5", kill_on_drop: false }`
[INFO] [stderr] warning: virtual workspace defaulting to `resolver = "1"` despite one or more workspace members being on edition 2021 which implies `resolver = "2"`
[INFO] [stderr] note: to keep the current resolver, specify `workspace.resolver = "1"` in the workspace root's manifest
[INFO] [stderr] note: to use the edition 2021 resolver, specify `workspace.resolver = "2"` in the workspace root's manifest
[INFO] [stderr] note: for more details see https://doc.rust-lang.org/cargo/reference/resolver.html#resolver-versions
[INFO] [stderr]    Compiling unicode-ident v1.0.5
[INFO] [stderr]    Compiling quote v1.0.26
[INFO] [stderr]     Checking pin-project-lite v0.2.9
[INFO] [stderr]    Compiling libc v0.2.138
[INFO] [stderr]    Compiling syn v1.0.105
[INFO] [stderr]     Checking once_cell v1.16.0
[INFO] [stderr]    Compiling futures-core v0.3.28
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]    Compiling futures-channel v0.3.28
[INFO] [stderr]    Compiling serde_derive v1.0.160
[INFO] [stderr]    Compiling futures-task v0.3.28
[INFO] [stderr]     Checking regex-syntax v0.6.28
[INFO] [stderr]    Compiling slab v0.4.8
[INFO] [stderr]    Compiling tokio v1.27.0
[INFO] [stderr]    Compiling serde v1.0.160
[INFO] [stderr]    Compiling futures-util v0.3.28
[INFO] [stderr]     Checking futures-sink v0.3.28
[INFO] [stderr]    Compiling proc-macro2 v1.0.56
[INFO] [stderr]     Checking overload v0.1.1
[INFO] [stderr]     Checking tracing-core v0.1.30
[INFO] [stderr]    Compiling serde_json v1.0.96
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-6f17d22bba15001f/proc-macro2-1.0.56/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]     Checking futures-io v0.3.28
[INFO] [stderr]     Checking nu-ansi-term v0.46.0
[INFO] [stderr]     Checking thread_local v1.1.4
[INFO] [stderr]     Checking sharded-slab v0.1.4
[INFO] [stderr]     Checking smallvec v1.10.0
[INFO] [stderr]     Checking itoa v1.0.6
[INFO] [stderr]     Checking ryu v1.0.13
[INFO] [stderr]     Checking lib-and-main-ex1 v0.1.0 (/opt/rustwide/workdir/experiments/lib-and-main-ex1)
[INFO] [stderr]     Checking stdin-take-nums v0.1.0 (/opt/rustwide/workdir/experiments/stdin-take-nums)
[INFO] [stderr]     Checking ast-visitor-etc v0.1.0 (/opt/rustwide/workdir/experiments/ast-visitor-etc)
[INFO] [stdout] error: aborting due to 1 previous error
[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 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "eaa5625ee246832b9a1fd81281fa2075517ee7a799e94be358a2b5e41def16e5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "eaa5625ee246832b9a1fd81281fa2075517ee7a799e94be358a2b5e41def16e5", kill_on_drop: false }`
[INFO] [stdout] eaa5625ee246832b9a1fd81281fa2075517ee7a799e94be358a2b5e41def16e5