[INFO] cloning repository https://github.com/imtsuki/xv7
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/imtsuki/xv7" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fimtsuki%2Fxv7", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fimtsuki%2Fxv7'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] d38cb191ab05681b492ac578f3973ffd887bf091
[INFO] checking imtsuki/xv7 against master#195ad4830e11a544391abe296b146450dea8411b for pr-82781
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fimtsuki%2Fxv7" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/imtsuki/xv7 on toolchain 195ad4830e11a544391abe296b146450dea8411b
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+195ad4830e11a544391abe296b146450dea8411b" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/imtsuki/xv7
[INFO] finished tweaking git repo https://github.com/imtsuki/xv7
[INFO] tweaked toml for git repo https://github.com/imtsuki/xv7 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/imtsuki/xv7 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+195ad4830e11a544391abe296b146450dea8411b" "fetch" "--locked" "--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-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+195ad4830e11a544391abe296b146450dea8411b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 022ffa75d26b90aa39d5f4846a498ab7965ff68553b630eb10fccdd1e9e9623f
[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" "022ffa75d26b90aa39d5f4846a498ab7965ff68553b630eb10fccdd1e9e9623f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "022ffa75d26b90aa39d5f4846a498ab7965ff68553b630eb10fccdd1e9e9623f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "022ffa75d26b90aa39d5f4846a498ab7965ff68553b630eb10fccdd1e9e9623f", kill_on_drop: false }`
[INFO] [stdout] 022ffa75d26b90aa39d5f4846a498ab7965ff68553b630eb10fccdd1e9e9623f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+195ad4830e11a544391abe296b146450dea8411b" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e2a908aac54117b77a2fef13df9c8788d7449b8c71118ccb487de032d5d1a6a3
[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" "e2a908aac54117b77a2fef13df9c8788d7449b8c71118ccb487de032d5d1a6a3", kill_on_drop: false }`
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling syn v1.0.38
[INFO] [stderr]    Compiling x86_64 v0.11.1
[INFO] [stderr]    Compiling autocfg v1.0.0
[INFO] [stderr]    Compiling memchr v2.3.3
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]     Checking bit_field v0.9.0
[INFO] [stderr]     Checking bit_field v0.10.0
[INFO] [stderr]     Checking xv7-usyscall v0.1.0 (/opt/rustwide/workdir/xv7-usyscall)
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]     Checking plain v0.2.3
[INFO] [stderr]     Checking radium v0.3.0
[INFO] [stderr]     Checking utf8parse v0.2.0
[INFO] [stderr]     Checking zeroize v1.1.0
[INFO] [stderr]     Checking arrayvec v0.5.1
[INFO] [stderr]     Checking either v1.5.3
[INFO] [stderr]     Checking spin v0.5.2
[INFO] [stderr]     Checking pc-keyboard v0.5.1
[INFO] [stderr]    Compiling nom v5.1.2
[INFO] [stderr]     Checking lock_api v0.3.4
[INFO] [stderr]     Checking xv7-user v0.1.0 (/opt/rustwide/workdir/xv7-user)
[INFO] [stderr]     Checking ucs2 v0.3.1
[INFO] [stdout] warning: `extern` fn uses type `fn() -> T`, which is not FFI-safe
[INFO] [stdout]   --> xv7-user/src/rt.rs:21:11
[INFO] [stdout]    |
[INFO] [stdout] 21 |     main: fn() -> T,
[INFO] [stdout]    |           ^^^^^^^^^ not FFI-safe
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(improper_ctypes_definitions)]` on by default
[INFO] [stdout]    = help: consider using an `extern fn(...) -> ...` function pointer instead
[INFO] [stdout]    = note: this function pointer has Rust-specific calling convention
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `extern` fn uses type `fn() -> T`, which is not FFI-safe
[INFO] [stdout]   --> xv7-user/src/rt.rs:21:11
[INFO] [stdout]    |
[INFO] [stdout] 21 |     main: fn() -> T,
[INFO] [stdout]    |           ^^^^^^^^^ not FFI-safe
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(improper_ctypes_definitions)]` on by default
[INFO] [stdout]    = help: consider using an `extern fn(...) -> ...` function pointer instead
[INFO] [stdout]    = note: this function pointer has Rust-specific calling convention
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]    Compiling proc-macro2 v1.0.19
[INFO] [stderr]     Checking log v0.4.11
[INFO] [stderr]     Checking bitvec v0.17.4
[INFO] [stderr]     Checking spinning_top v0.1.1
[INFO] [stdout] error: duplicate lang item in crate `std` (which `test` depends on): `panic_impl`.
[INFO] [stdout]   |
[INFO] [stdout]   = note: the lang item is first defined in crate `xv7_user` (which `init` depends on)
[INFO] [stdout]   = note: first definition in `xv7_user` loaded from /opt/rustwide/target/debug/deps/libxv7_user-b407318c2d3c4c42.rmeta
[INFO] [stdout]   = note: second definition in `std` loaded from /opt/rustwide/rustup-home/toolchains/195ad4830e11a544391abe296b146450dea8411b/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd-3d933644112ba794.rlib
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: duplicate lang item in crate `std` (which `test` depends on): `start`.
[INFO] [stdout]   |
[INFO] [stdout]   = note: the lang item is first defined in crate `xv7_user` (which `init` depends on)
[INFO] [stdout]   = note: first definition in `xv7_user` loaded from /opt/rustwide/target/debug/deps/libxv7_user-b407318c2d3c4c42.rmeta
[INFO] [stdout]   = note: second definition in `std` loaded from /opt/rustwide/rustup-home/toolchains/195ad4830e11a544391abe296b146450dea8411b/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd-3d933644112ba794.rlib
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `xv7-user`
[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" "e2a908aac54117b77a2fef13df9c8788d7449b8c71118ccb487de032d5d1a6a3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e2a908aac54117b77a2fef13df9c8788d7449b8c71118ccb487de032d5d1a6a3", kill_on_drop: false }`
[INFO] [stdout] e2a908aac54117b77a2fef13df9c8788d7449b8c71118ccb487de032d5d1a6a3