[INFO] fetching crate slabmalloc 0.7.0...
[INFO] checking slabmalloc-0.7.0 against try#bb9dbf1d07454a99066eabaabd5819851281494b for pr-80920
[INFO] extracting crate slabmalloc 0.7.0 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate slabmalloc 0.7.0 on toolchain bb9dbf1d07454a99066eabaabd5819851281494b
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+bb9dbf1d07454a99066eabaabd5819851281494b" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate slabmalloc 0.7.0
[INFO] finished tweaking crates.io crate slabmalloc 0.7.0
[INFO] tweaked toml for crates.io crate slabmalloc 0.7.0 written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] crate crates.io crate slabmalloc 0.7.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+bb9dbf1d07454a99066eabaabd5819851281494b" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded wasi v0.7.0
[INFO] [stderr]   Downloaded winapi-util v0.1.2
[INFO] [stderr]   Downloaded quick-error v1.2.2
[INFO] [stderr]   Downloaded c2-chacha v0.2.3
[INFO] [stderr]   Downloaded rand v0.7.2
[INFO] [stderr]   Downloaded libc v0.2.65
[INFO] [stderr]   Downloaded getrandom v0.1.13
[INFO] [stderr]   Downloaded wincolor v1.0.2
[INFO] [stderr]   Downloaded termcolor v1.0.5
[INFO] [stderr]   Downloaded rand_chacha v0.2.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "rustops/crates-build-env@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+bb9dbf1d07454a99066eabaabd5819851281494b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0f0871af6b8a4350b1b456b6eed57f8617ef97bc6cb7ab7dec02bb5696c05362
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "0f0871af6b8a4350b1b456b6eed57f8617ef97bc6cb7ab7dec02bb5696c05362", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0f0871af6b8a4350b1b456b6eed57f8617ef97bc6cb7ab7dec02bb5696c05362", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0f0871af6b8a4350b1b456b6eed57f8617ef97bc6cb7ab7dec02bb5696c05362", kill_on_drop: false }`
[INFO] [stdout] 0f0871af6b8a4350b1b456b6eed57f8617ef97bc6cb7ab7dec02bb5696c05362
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+bb9dbf1d07454a99066eabaabd5819851281494b" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 663a1206fb8b6cb18ef0a2b9841ad6d62a38064addd226120e7d76dcaaa4fadc
[INFO] running `Command { std: "docker" "start" "-a" "663a1206fb8b6cb18ef0a2b9841ad6d62a38064addd226120e7d76dcaaa4fadc", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.65
[INFO] [stderr]    Compiling getrandom v0.1.13
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]     Checking regex-syntax v0.6.12
[INFO] [stderr]     Checking c2-chacha v0.2.3
[INFO] [stderr]     Checking thread_local v0.3.6
[INFO] [stderr]     Checking slabmalloc v0.7.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0658]: mutable references are not allowed in constant functions
[INFO] [stdout]    --> src/pages.rs:349:19
[INFO] [stdout]     |
[INFO] [stdout] 349 |             head: None,
[INFO] [stdout]     |                   ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
[INFO] [stdout]     = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0658`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `slabmalloc`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "663a1206fb8b6cb18ef0a2b9841ad6d62a38064addd226120e7d76dcaaa4fadc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "663a1206fb8b6cb18ef0a2b9841ad6d62a38064addd226120e7d76dcaaa4fadc", kill_on_drop: false }`
[INFO] [stdout] 663a1206fb8b6cb18ef0a2b9841ad6d62a38064addd226120e7d76dcaaa4fadc