[INFO] updating cached repository AleVul/kernel_playground
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/AleVul/kernel_playground
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/AleVul/kernel_playground" "work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/AleVul/kernel_playground"`
[INFO] [stderr] Cloning into 'work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/AleVul/kernel_playground'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/AleVul/kernel_playground" "work/ex/pr-57967/sources/try#7fea0229842e79db1159ea58ad9a653b288efee9/gh/AleVul/kernel_playground"`
[INFO] [stderr] Cloning into 'work/ex/pr-57967/sources/try#7fea0229842e79db1159ea58ad9a653b288efee9/gh/AleVul/kernel_playground'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] f2027c0a818473d324ee67f318f2235c5d7b7ab1
[INFO] sha for GitHub repo AleVul/kernel_playground: f2027c0a818473d324ee67f318f2235c5d7b7ab1
[INFO] validating manifest of AleVul/kernel_playground on toolchain master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of AleVul/kernel_playground on toolchain try#7fea0229842e79db1159ea58ad9a653b288efee9
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+7fea0229842e79db1159ea58ad9a653b288efee9-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing AleVul/kernel_playground
[INFO] finished frobbing AleVul/kernel_playground
[INFO] frobbed toml for AleVul/kernel_playground written to work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/AleVul/kernel_playground/Cargo.toml
[INFO] started frobbing AleVul/kernel_playground
[INFO] finished frobbing AleVul/kernel_playground
[INFO] frobbed toml for AleVul/kernel_playground written to work/ex/pr-57967/sources/try#7fea0229842e79db1159ea58ad9a653b288efee9/gh/AleVul/kernel_playground/Cargo.toml
[INFO] crate AleVul/kernel_playground has a lockfile. skipping
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+7fea0229842e79db1159ea58ad9a653b288efee9-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing AleVul/kernel_playground against master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54 for pr-57967
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-57967/worker-1/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-57967/sources/master#c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54/gh/AleVul/kernel_playground:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt" "build" "--frozen"`
[INFO] [stdout] 5468a7fc0c19ff4f9a82f9d3c743719737bd0a2bb8407cc30746d4310eafb35d
[INFO] running `"docker" "start" "-a" "5468a7fc0c19ff4f9a82f9d3c743719737bd0a2bb8407cc30746d4310eafb35d"`
[INFO] [stderr]     Blocking waiting for file lock on the registry index
[INFO] [stderr]    Compiling x86_64 v0.2.11
[INFO] [stderr]    Compiling bootloader_precompiled v0.3.0
[INFO] [stderr]    Compiling kernel_playground v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] error: linking with `cc` failed: exit code: 1
[INFO] [stderr]   |
[INFO] [stderr]   = note: "cc" "-Wl,--as-needed" "-Wl,-z,noexecstack" "-m64" "-L" "/opt/crater/rustup-home/toolchains/c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt/lib/rustlib/x86_64-unknown-linux-gnu/lib" "/opt/crater/target/debug/deps/kernel_playground-a19ef4c98ab20d7c.kernel_playground.3udra6gk-cgu.0.rcgu.o" "/opt/crater/target/debug/deps/kernel_playground-a19ef4c98ab20d7c.kernel_playground.3udra6gk-cgu.1.rcgu.o" "/opt/crater/target/debug/deps/kernel_playground-a19ef4c98ab20d7c.kernel_playground.3udra6gk-cgu.2.rcgu.o" "/opt/crater/target/debug/deps/kernel_playground-a19ef4c98ab20d7c.kernel_playground.3udra6gk-cgu.3.rcgu.o" "/opt/crater/target/debug/deps/kernel_playground-a19ef4c98ab20d7c.kernel_playground.3udra6gk-cgu.4.rcgu.o" "-o" "/opt/crater/target/debug/deps/kernel_playground-a19ef4c98ab20d7c" "-Wl,--gc-sections" "-pie" "-Wl,-zrelro" "-Wl,-znow" "-nodefaultlibs" "-L" "/opt/crater/target/debug/deps" "-L" "/opt/crater/rustup-home/toolchains/c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-Wl,-Bstatic" "/opt/crater/target/debug/deps/libbootloader_precompiled-82278150738e4b52.rlib" "/opt/crater/target/debug/deps/libx86_64-5ebda0a87d3d80fe.rlib" "/opt/crater/target/debug/deps/libux-f046ef8639a97fac.rlib" "/opt/crater/target/debug/deps/libusize_conversions-0c602e12466637a0.rlib" "/opt/crater/target/debug/deps/libos_bootinfo-36a09524eb3c4506.rlib" "/opt/crater/target/debug/deps/libbit_field-d60074bc29032aac.rlib" "/opt/crater/target/debug/deps/libbitflags-a2e3757c0b607ad2.rlib" "/opt/crater/rustup-home/toolchains/c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_core-57f280c1596673cd.rlib" "/opt/crater/rustup-home/toolchains/c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-16132b5b2ecf9ec1.rlib" "/opt/crater/rustup-home/toolchains/c1c3c4e95b69dfeaca5c5db6c622d7f90ad30a54-alt/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcompiler_builtins-37286a0a9c4289ff.rlib" "-Wl,-Bdynamic"
[INFO] [stderr]   = note: /opt/crater/target/debug/deps/kernel_playground-a19ef4c98ab20d7c.kernel_playground.3udra6gk-cgu.3.rcgu.o: In function `_start':
[INFO] [stderr]           /opt/crater/workdir/src/main.rs:17: multiple definition of `_start'
[INFO] [stderr]           /usr/lib/gcc/x86_64-linux-gnu/6/../../../x86_64-linux-gnu/Scrt1.o:(.text+0x0): first defined here
[INFO] [stderr]           /usr/lib/gcc/x86_64-linux-gnu/6/../../../x86_64-linux-gnu/Scrt1.o: In function `_start':
[INFO] [stderr]           (.text+0x12): undefined reference to `__libc_csu_fini'
[INFO] [stderr]           /usr/lib/gcc/x86_64-linux-gnu/6/../../../x86_64-linux-gnu/Scrt1.o: In function `_start':
[INFO] [stderr]           (.text+0x19): undefined reference to `__libc_csu_init'
[INFO] [stderr]           /usr/lib/gcc/x86_64-linux-gnu/6/../../../x86_64-linux-gnu/Scrt1.o: In function `_start':
[INFO] [stderr]           (.text+0x20): undefined reference to `main'
[INFO] [stderr]           /usr/lib/gcc/x86_64-linux-gnu/6/../../../x86_64-linux-gnu/Scrt1.o: In function `_start':
[INFO] [stderr]           (.text+0x26): undefined reference to `__libc_start_main'
[INFO] [stderr]           collect2: error: ld returned 1 exit status
[INFO] [stderr]           
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] error: Could not compile `kernel_playground`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "5468a7fc0c19ff4f9a82f9d3c743719737bd0a2bb8407cc30746d4310eafb35d"`
[INFO] running `"docker" "rm" "-f" "5468a7fc0c19ff4f9a82f9d3c743719737bd0a2bb8407cc30746d4310eafb35d"`
[INFO] [stdout] 5468a7fc0c19ff4f9a82f9d3c743719737bd0a2bb8407cc30746d4310eafb35d