[INFO] cloning repository https://github.com/creativcoder/rust_calls_cpp
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/creativcoder/rust_calls_cpp" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcreativcoder%2Frust_calls_cpp", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcreativcoder%2Frust_calls_cpp'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 68b4719e8b7fd7777c22445a842378055c7c5f4e
[INFO] testing creativcoder/rust_calls_cpp against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcreativcoder%2Frust_calls_cpp" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/creativcoder/rust_calls_cpp on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/creativcoder/rust_calls_cpp
[INFO] finished tweaking git repo https://github.com/creativcoder/rust_calls_cpp
[INFO] tweaked toml for git repo https://github.com/creativcoder/rust_calls_cpp written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/creativcoder/rust_calls_cpp already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--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-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] cb1a431ffeb37d7e5699109cbb5f3e7f064ee8e519eafedb401819f2a7c1ea42
[INFO] running `Command { std: "docker" "start" "-a" "cb1a431ffeb37d7e5699109cbb5f3e7f064ee8e519eafedb401819f2a7c1ea42", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cb1a431ffeb37d7e5699109cbb5f3e7f064ee8e519eafedb401819f2a7c1ea42", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cb1a431ffeb37d7e5699109cbb5f3e7f064ee8e519eafedb401819f2a7c1ea42", kill_on_drop: false }`
[INFO] [stdout] cb1a431ffeb37d7e5699109cbb5f3e7f064ee8e519eafedb401819f2a7c1ea42
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 578d59b7d9538bfed4d23983a96a7a8c950e73bccd1b3db66073a7737406d6ae
[INFO] running `Command { std: "docker" "start" "-a" "578d59b7d9538bfed4d23983a96a7a8c950e73bccd1b3db66073a7737406d6ae", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling rust_calls_cpp v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> src/main.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(link_args)]
[INFO] [stdout]   |            ^^^^^^^^^ feature has been removed
[INFO] [stdout]   |
[INFO] [stdout]   = note: removed in favor of using `-C link-arg=ARG` on command line, which is available from cargo build scripts with `cargo:rustc-link-arg` now
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: cannot find attribute `link_args` in this scope
[INFO] [stdout]  --> src/main.rs:9:3
[INFO] [stdout]   |
[INFO] [stdout] 9 | #[link_args = "-lstdc++ -Wl,-rpath,lib"]
[INFO] [stdout]   |   ^^^^^^^^^ help: a built-in attribute with a similar name exists: `linkage`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(libc)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(link_args)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead?
[INFO] [stdout]  --> src/main.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | extern crate libc;
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: see issue #27812 <https://github.com/rust-lang/rust/issues/27812> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead?
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use libc::size_t;
[INFO] [stdout]   |     ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: see issue #27812 <https://github.com/rust-lang/rust/issues/27812> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead?
[INFO] [stdout]   --> src/main.rs:11:15
[INFO] [stdout]    |
[INFO] [stdout] 11 |     fn add(a: size_t, b: size_t) -> size_t;
[INFO] [stdout]    |               ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #27812 <https://github.com/rust-lang/rust/issues/27812> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead?
[INFO] [stdout]   --> src/main.rs:11:26
[INFO] [stdout]    |
[INFO] [stdout] 11 |     fn add(a: size_t, b: size_t) -> size_t;
[INFO] [stdout]    |                          ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #27812 <https://github.com/rust-lang/rust/issues/27812> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead?
[INFO] [stdout]   --> src/main.rs:11:37
[INFO] [stdout]    |
[INFO] [stdout] 11 |     fn add(a: size_t, b: size_t) -> size_t;
[INFO] [stdout]    |                                     ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #27812 <https://github.com/rust-lang/rust/issues/27812> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 9 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0557, E0658.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rust_calls_cpp` due to 10 previous errors
[INFO] running `Command { std: "docker" "inspect" "578d59b7d9538bfed4d23983a96a7a8c950e73bccd1b3db66073a7737406d6ae", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "578d59b7d9538bfed4d23983a96a7a8c950e73bccd1b3db66073a7737406d6ae", kill_on_drop: false }`
[INFO] [stdout] 578d59b7d9538bfed4d23983a96a7a8c950e73bccd1b3db66073a7737406d6ae