[INFO] cloning repository https://github.com/tiqwab/xv6-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/tiqwab/xv6-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftiqwab%2Fxv6-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftiqwab%2Fxv6-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 525899393df10855a274ce0a9d4e5841aa032aeb
[INFO] checking tiqwab/xv6-rust against try#f47dd4da3ae8c32c9e65d307bfe640b143e674df for pr-77526
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftiqwab%2Fxv6-rust" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/tiqwab/xv6-rust on toolchain f47dd4da3ae8c32c9e65d307bfe640b143e674df
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/tiqwab/xv6-rust
[INFO] finished tweaking git repo https://github.com/tiqwab/xv6-rust
[INFO] tweaked toml for git repo https://github.com/tiqwab/xv6-rust written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/tiqwab/xv6-rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] aaf452e76f4282d5801b889eb5661be178fdbf5738354135497fde20636f382b
[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" "aaf452e76f4282d5801b889eb5661be178fdbf5738354135497fde20636f382b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "aaf452e76f4282d5801b889eb5661be178fdbf5738354135497fde20636f382b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "aaf452e76f4282d5801b889eb5661be178fdbf5738354135497fde20636f382b", kill_on_drop: false }`
[INFO] [stdout] aaf452e76f4282d5801b889eb5661be178fdbf5738354135497fde20636f382b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] eca5829a47b753cc5408090bde3407294cbb6c39367f92e5491adb26559cb727
[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" "eca5829a47b753cc5408090bde3407294cbb6c39367f92e5491adb26559cb727", kill_on_drop: false }`
[INFO] [stderr]     Checking lock_api v0.3.4
[INFO] [stderr]    Compiling xv6-rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking spinning_top v0.1.0
[INFO] [stderr]     Checking linked_list_allocator v0.8.4
[INFO] [stderr] The following warnings were emitted during compilation:
[INFO] [stderr] 
[INFO] [stderr] warning: src/entry.S: Assembler messages:
[INFO] [stderr] warning: src/entry.S:78: Error: unsupported instruction `mov'
[INFO] [stderr] warning: src/entry.S:80: Error: unsupported instruction `mov'
[INFO] [stderr] warning: src/entry.S:82: Error: unsupported instruction `mov'
[INFO] [stderr] warning: src/entry.S:88: Error: operand type mismatch for `jmp'
[INFO] [stderr] 
[INFO] [stderr] error: failed to run custom build command for `xv6-rust v0.1.0 (/opt/rustwide/workdir)`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `/opt/rustwide/target/debug/build/xv6-rust-a6594edeb0424fcc/build-script-build` (exit code: 1)
[INFO] [stderr]   --- stdout
[INFO] [stderr]   TARGET = Some("x86_64-unknown-linux-gnu")
[INFO] [stderr]   OPT_LEVEL = Some("0")
[INFO] [stderr]   HOST = Some("x86_64-unknown-linux-gnu")
[INFO] [stderr]   CC_x86_64-unknown-linux-gnu = None
[INFO] [stderr]   CC_x86_64_unknown_linux_gnu = None
[INFO] [stderr]   HOST_CC = None
[INFO] [stderr]   CC = None
[INFO] [stderr]   CFLAGS_x86_64-unknown-linux-gnu = None
[INFO] [stderr]   CFLAGS_x86_64_unknown_linux_gnu = None
[INFO] [stderr]   HOST_CFLAGS = None
[INFO] [stderr]   CFLAGS = None
[INFO] [stderr]   CRATE_CC_NO_DEFAULTS = None
[INFO] [stderr]   DEBUG = Some("true")
[INFO] [stderr]   CARGO_CFG_TARGET_FEATURE = Some("fxsr,sse,sse2")
[INFO] [stderr]   running: "cc" "-O0" "-ffunction-sections" "-fdata-sections" "-fPIC" "-g" "-fno-omit-frame-pointer" "-m64" "-I" "inc" "-Wall" "-Wextra" "-o" "/opt/rustwide/target/debug/build/xv6-rust-5e8ee259809c5edb/out/src/entry.o" "-c" "src/entry.S"
[INFO] [stderr]   cargo:warning=src/entry.S: Assembler messages:
[INFO] [stderr]   cargo:warning=src/entry.S:78: Error: unsupported instruction `mov'
[INFO] [stderr]   cargo:warning=src/entry.S:80: Error: unsupported instruction `mov'
[INFO] [stderr]   cargo:warning=src/entry.S:82: Error: unsupported instruction `mov'
[INFO] [stderr]   cargo:warning=src/entry.S:88: Error: operand type mismatch for `jmp'
[INFO] [stderr]   exit code: 1
[INFO] [stderr] 
[INFO] [stderr]   --- stderr
[INFO] [stderr] 
[INFO] [stderr] 
[INFO] [stderr]   error occurred: Command "cc" "-O0" "-ffunction-sections" "-fdata-sections" "-fPIC" "-g" "-fno-omit-frame-pointer" "-m64" "-I" "inc" "-Wall" "-Wextra" "-o" "/opt/rustwide/target/debug/build/xv6-rust-5e8ee259809c5edb/out/src/entry.o" "-c" "src/entry.S" with args "cc" did not execute successfully (status code exit code: 1).
[INFO] [stderr] 
[INFO] [stderr] 
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error[E0658]: mutable references are not allowed in constant functions
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/linked_list_allocator-0.8.4/src/hole.rs:18:23
[INFO] [stdout]    |
[INFO] [stdout] 18 |                 next: 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: build failed
[INFO] running `Command { std: "docker" "inspect" "eca5829a47b753cc5408090bde3407294cbb6c39367f92e5491adb26559cb727", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "eca5829a47b753cc5408090bde3407294cbb6c39367f92e5491adb26559cb727", kill_on_drop: false }`
[INFO] [stdout] eca5829a47b753cc5408090bde3407294cbb6c39367f92e5491adb26559cb727