[INFO] fetching crate l4rs 0.1.0...
[INFO] testing l4rs-0.1.0 against 1.49.0 for beta-1.50-1
[INFO] extracting crate l4rs 0.1.0 into /workspace/builds/worker-13/source
[INFO] validating manifest of crates.io crate l4rs 0.1.0 on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-13/source/.cargo/config
[INFO] started tweaking crates.io crate l4rs 0.1.0
[INFO] finished tweaking crates.io crate l4rs 0.1.0
[INFO] tweaked toml for crates.io crate l4rs 0.1.0 written to /workspace/builds/worker-13/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "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-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "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] 0486fbbcc3f52c31a3eec8b790bf3a8681f65ef207ae1c7b103c496c149f794d
[INFO] running `Command { std: "docker" "start" "-a" "0486fbbcc3f52c31a3eec8b790bf3a8681f65ef207ae1c7b103c496c149f794d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0486fbbcc3f52c31a3eec8b790bf3a8681f65ef207ae1c7b103c496c149f794d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0486fbbcc3f52c31a3eec8b790bf3a8681f65ef207ae1c7b103c496c149f794d", kill_on_drop: false }`
[INFO] [stdout] 0486fbbcc3f52c31a3eec8b790bf3a8681f65ef207ae1c7b103c496c149f794d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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" "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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 51d2577fb352212f42a6118b5a607d392a73196f221b7de599072b12b54c4672
[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" "51d2577fb352212f42a6118b5a607d392a73196f221b7de599072b12b54c4672", kill_on_drop: false }`
[INFO] [stderr]    Compiling l4rs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error: linking with `cc` failed: exit code: 1
[INFO] [stdout]   |
[INFO] [stdout]   = note: "cc" "-Wl,--as-needed" "-Wl,-z,noexecstack" "-m64" "-Wl,--eh-frame-hdr" "-L" "/opt/rustwide/rustup-home/toolchains/1.49.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib" "/opt/rustwide/target/debug/deps/bootstrap-ca7d669f47b6bd03.bootstrap.6pwyej5t-cgu.0.rcgu.o" "-o" "/opt/rustwide/target/debug/deps/bootstrap-ca7d669f47b6bd03" "-Wl,--gc-sections" "-pie" "-Wl,-zrelro" "-Wl,-znow" "-nodefaultlibs" "-L" "/opt/rustwide/target/debug/deps" "-L" "/opt/rustwide/rustup-home/toolchains/1.49.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-Wl,-Bstatic" "/opt/rustwide/rustup-home/toolchains/1.49.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_core-25b7435131fc4938.rlib" "/opt/rustwide/rustup-home/toolchains/1.49.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-9d4b6f3c097e876e.rlib" "/opt/rustwide/rustup-home/toolchains/1.49.0-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcompiler_builtins-3f953ad652ab829a.rlib" "-Wl,-Bdynamic"
[INFO] [stdout]   = note: /usr/bin/ld: /opt/rustwide/target/debug/deps/bootstrap-ca7d669f47b6bd03.bootstrap.6pwyej5t-cgu.0.rcgu.o: in function `_start':
[INFO] [stdout]           /opt/rustwide/workdir/bootstrap/main.rs:9: 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
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `l4rs`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "51d2577fb352212f42a6118b5a607d392a73196f221b7de599072b12b54c4672", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "51d2577fb352212f42a6118b5a607d392a73196f221b7de599072b12b54c4672", kill_on_drop: false }`
[INFO] [stdout] 51d2577fb352212f42a6118b5a607d392a73196f221b7de599072b12b54c4672