[INFO] fetching crate arcstring 1.0.0...
[INFO] checking arcstring-1.0.0 against 1.94.0 for beta-1.95-4
[INFO] extracting crate arcstring 1.0.0 into /workspace/builds/worker-3-tc1/source
[INFO] started tweaking crates.io crate arcstring 1.0.0
[INFO] removed 0 missing tests
[INFO] finished tweaking crates.io crate arcstring 1.0.0
[INFO] tweaked toml for crates.io crate arcstring 1.0.0 written to /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate arcstring 1.0.0 on toolchain 1.94.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.94.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate arcstring 1.0.0 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" "+1.94.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.94.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] fba4db7779fbad9c1026ef5b92063eace86d22acd11e08238c5101e84e3549a9
[INFO] running `Command { std: "docker" "start" "-a" "fba4db7779fbad9c1026ef5b92063eace86d22acd11e08238c5101e84e3549a9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "fba4db7779fbad9c1026ef5b92063eace86d22acd11e08238c5101e84e3549a9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fba4db7779fbad9c1026ef5b92063eace86d22acd11e08238c5101e84e3549a9", kill_on_drop: false }`
[INFO] [stdout] fba4db7779fbad9c1026ef5b92063eace86d22acd11e08238c5101e84e3549a9
[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=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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.94.0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5e4e9f55c08c3744f47eb665985999afa39f43c4fee7f2e2a76374bf2f2bb72c
[INFO] running `Command { std: "docker" "start" "-a" "5e4e9f55c08c3744f47eb665985999afa39f43c4fee7f2e2a76374bf2f2bb72c", kill_on_drop: false }`
[INFO] [stderr]     Checking arcstring v1.0.0 (/opt/rustwide/workdir)
[INFO] [stderr] error: could not compile `arcstring` (lib) due to 2 previous errors
[INFO] [stdout] error[E0658]: use of unstable library feature `ptr_as_ref_unchecked`
[INFO] [stdout]    --> src/builder.rs:103:113
[INFO] [stdout]     |
[INFO] [stdout] 103 | ...rts(self.get_data_ptr().as_ptr(), self.length as usize).as_ref_unchecked())
[INFO] [stdout]     |                                                            ^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #122034 <https://github.com/rust-lang/rust/issues/122034> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error[E0658]: use of unstable library feature `ptr_as_ref_unchecked`
[INFO] [stdout]    --> src/builder.rs:109:121
[INFO] [stdout]     |
[INFO] [stdout] 109 | ...mut(self.get_data_ptr().as_ptr(), self.length as usize).as_mut_unchecked())
[INFO] [stdout]     |                                                            ^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #122034 <https://github.com/rust-lang/rust/issues/122034> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: use of unstable library feature `ptr_as_ref_unchecked`
[INFO] [stdout]    --> src/builder.rs:103:113
[INFO] [stdout]     |
[INFO] [stdout] 103 | ...rts(self.get_data_ptr().as_ptr(), self.length as usize).as_ref_unchecked())
[INFO] [stdout]     |                                                            ^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #122034 <https://github.com/rust-lang/rust/issues/122034> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: use of unstable library feature `ptr_as_ref_unchecked`
[INFO] [stdout]    --> src/builder.rs:109:121
[INFO] [stdout]     |
[INFO] [stdout] 109 | ...mut(self.get_data_ptr().as_ptr(), self.length as usize).as_mut_unchecked())
[INFO] [stdout]     |                                                            ^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #122034 <https://github.com/rust-lang/rust/issues/122034> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0658`.
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0658`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `arcstring` (lib test) due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "5e4e9f55c08c3744f47eb665985999afa39f43c4fee7f2e2a76374bf2f2bb72c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5e4e9f55c08c3744f47eb665985999afa39f43c4fee7f2e2a76374bf2f2bb72c", kill_on_drop: false }`
[INFO] [stdout] 5e4e9f55c08c3744f47eb665985999afa39f43c4fee7f2e2a76374bf2f2bb72c