[INFO] cloning repository https://github.com/abbychau/a_core
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/abbychau/a_core" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fabbychau%2Fa_core", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fabbychau%2Fa_core'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] cf22720717cc9dbf9abc4e681d2827619c68646e
[INFO] testing abbychau/a_core against 1.45.2 for beta-1.46-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fabbychau%2Fa_core" "/workspace/builds/worker-2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/abbychau/a_core on toolchain 1.45.2
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.45.2" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-2/source/.cargo/config
[INFO] started tweaking git repo https://github.com/abbychau/a_core
[INFO] finished tweaking git repo https://github.com/abbychau/a_core
[INFO] tweaked toml for git repo https://github.com/abbychau/a_core written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/abbychau/a_core already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.45.2" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+1.45.2" "metadata" "--no-deps" "--format-version=1", 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] 78af29c7f24473dc74481efa2928f8a11fa023b1956295a69a90dd54cea8f79c
[INFO] running `Command { std: "docker" "start" "-a" "78af29c7f24473dc74481efa2928f8a11fa023b1956295a69a90dd54cea8f79c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "78af29c7f24473dc74481efa2928f8a11fa023b1956295a69a90dd54cea8f79c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "78af29c7f24473dc74481efa2928f8a11fa023b1956295a69a90dd54cea8f79c", kill_on_drop: false }`
[INFO] [stdout] 78af29c7f24473dc74481efa2928f8a11fa023b1956295a69a90dd54cea8f79c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "MAP_USER_ID=0" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+1.45.2" "build" "--frozen" "--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] e2e42f384c02083e592d9119ee1d0c8dc7ac58f3f0ddef037147ec28806f2e9f
[INFO] running `Command { std: "docker" "start" "-a" "e2e42f384c02083e592d9119ee1d0c8dc7ac58f3f0ddef037147ec28806f2e9f", kill_on_drop: false }`
[INFO] [stderr]    Compiling bootloader v0.9.2
[INFO] [stderr]    Compiling volatile v0.2.6
[INFO] [stderr]    Compiling a_core v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]    --> src/vga_buffer.rs:115:13
[INFO] [stdout]     |
[INFO] [stdout] 115 |         Err(e)=>{writer.write_string("ello! ");}
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: linking with `cc` failed: exit code: 1
[INFO] [stdout]   |
[INFO] [stdout]   = note: "cc" "-Wl,--as-needed" "-Wl,-z,noexecstack" "-m64" "-L" "/opt/rustwide/rustup-home/toolchains/1.45.2-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.0.rcgu.o" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.1.rcgu.o" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.10.rcgu.o" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.11.rcgu.o" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.12.rcgu.o" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.13.rcgu.o" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.14.rcgu.o" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.2.rcgu.o" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.3.rcgu.o" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.4.rcgu.o" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.5.rcgu.o" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.6.rcgu.o" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.7.rcgu.o" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.8.rcgu.o" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.9.rcgu.o" "-o" "/opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53" "-Wl,--gc-sections" "-pie" "-Wl,-zrelro" "-Wl,-znow" "-nodefaultlibs" "-L" "/opt/rustwide/target/debug/deps" "-L" "/opt/rustwide/rustup-home/toolchains/1.45.2-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-Wl,-Bstatic" "/opt/rustwide/target/debug/deps/libvolatile-874c8583e39d0caa.rlib" "/opt/rustwide/rustup-home/toolchains/1.45.2-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_core-09bd1119ab1cad7d.rlib" "/opt/rustwide/rustup-home/toolchains/1.45.2-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-9a787681bfbeaf61.rlib" "/opt/rustwide/rustup-home/toolchains/1.45.2-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcompiler_builtins-5a0398ee67f74664.rlib" "-Wl,-Bdynamic"
[INFO] [stdout]   = note: /usr/bin/ld: /opt/rustwide/target/debug/deps/a_core-5695c4adf43d6a53.a_core.4bfshqx2-cgu.2.rcgu.o: in function `_start':
[INFO] [stdout]           /opt/rustwide/workdir/src/main.rs:13: multiple definition of `_start'; /usr/lib/gcc/x86_64-linux-gnu/9/../../../x86_64-linux-gnu/Scrt1.o:(.text+0x0): first defined here
[INFO] [stdout]           /usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/9/../../../x86_64-linux-gnu/Scrt1.o: in function `_start':
[INFO] [stdout]           (.text+0x16): undefined reference to `__libc_csu_fini'
[INFO] [stdout]           /usr/bin/ld: (.text+0x1d): undefined reference to `__libc_csu_init'
[INFO] [stdout]           /usr/bin/ld: (.text+0x24): undefined reference to `main'
[INFO] [stdout]           /usr/bin/ld: (.text+0x2a): undefined reference to `__libc_start_main'
[INFO] [stdout]           collect2: error: ld returned 1 exit status
[INFO] [stdout]           
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `a_core`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "e2e42f384c02083e592d9119ee1d0c8dc7ac58f3f0ddef037147ec28806f2e9f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e2e42f384c02083e592d9119ee1d0c8dc7ac58f3f0ddef037147ec28806f2e9f", kill_on_drop: false }`
[INFO] [stdout] e2e42f384c02083e592d9119ee1d0c8dc7ac58f3f0ddef037147ec28806f2e9f