[INFO] fetching crate optimath 0.3.1...
[INFO] testing optimath-0.3.1 against 1.90.0 for beta-1.91-3
[INFO] extracting crate optimath 0.3.1 into /workspace/builds/worker-2-tc1/source
[INFO] started tweaking crates.io crate optimath 0.3.1
[INFO] finished tweaking crates.io crate optimath 0.3.1
[INFO] tweaked toml for crates.io crate optimath 0.3.1 written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate optimath 0.3.1 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 74 packages to latest compatible versions
[INFO] [stderr]       Adding bincode v1.3.3 (available: v2.0.1)
[INFO] [stderr]       Adding criterion v0.3.6 (available: v0.7.0)
[INFO] [stderr]       Adding rand v0.7.3 (available: v0.9.2)
[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] 51a6a59d39bdbad625e980f7f0982d843ab51bae702f51974c9534e8c3826bc8
[INFO] running `Command { std: "docker" "start" "-a" "51a6a59d39bdbad625e980f7f0982d843ab51bae702f51974c9534e8c3826bc8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "51a6a59d39bdbad625e980f7f0982d843ab51bae702f51974c9534e8c3826bc8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "51a6a59d39bdbad625e980f7f0982d843ab51bae702f51974c9534e8c3826bc8", kill_on_drop: false }`
[INFO] [stdout] 51a6a59d39bdbad625e980f7f0982d843ab51bae702f51974c9534e8c3826bc8
[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] dcde552e588e5b06f137814e93185f89142930ff39179318494d729c24e1bd67
[INFO] running `Command { std: "docker" "start" "-a" "dcde552e588e5b06f137814e93185f89142930ff39179318494d729c24e1bd67", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.176
[INFO] [stderr]    Compiling cfg-if v1.0.3
[INFO] [stderr]    Compiling getrandom v0.1.16
[INFO] [stderr]    Compiling zerocopy v0.8.27
[INFO] [stderr]    Compiling serde_core v1.0.228
[INFO] [stderr]    Compiling serde v1.0.228
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling ppv-lite86 v0.2.21
[INFO] [stderr]    Compiling rand_chacha v0.2.2
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling optimath v0.3.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(specialization)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(maybe_uninit_extra)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(array_methods)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `array_methods` has been stable since 1.77.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> src/lib.rs:6:12
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(array_methods)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `maybe_uninit_extra` has been stable since 1.60.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> src/lib.rs:4:12
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(maybe_uninit_extra)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `optimath` (lib) due to 3 previous errors; 2 warnings emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "dcde552e588e5b06f137814e93185f89142930ff39179318494d729c24e1bd67", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dcde552e588e5b06f137814e93185f89142930ff39179318494d729c24e1bd67", kill_on_drop: false }`
[INFO] [stdout] dcde552e588e5b06f137814e93185f89142930ff39179318494d729c24e1bd67