[INFO] fetching crate const-concat 0.1.0...
[INFO] checking const-concat-0.1.0 against master#2748a9fd93dd1a00a4521f4f16de5befbf77f6cd for pr-62262-1
[INFO] extracting crate const-concat 0.1.0 into /workspace/builds/worker-12/source
[INFO] validating manifest of crates.io crate const-concat 0.1.0 on toolchain 2748a9fd93dd1a00a4521f4f16de5befbf77f6cd
[INFO] running `"/workspace/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate const-concat 0.1.0
[INFO] finished tweaking crates.io crate const-concat 0.1.0
[INFO] tweaked toml for crates.io crate const-concat 0.1.0 written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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=forbid" "-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" "/opt/rustwide/cargo-home/bin/cargo" "+2748a9fd93dd1a00a4521f4f16de5befbf77f6cd" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] f09ff81781e392bbd9048a5c47f9ed191b0470d0ff6701e102df2f99494c3de7
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `"docker" "start" "-a" "f09ff81781e392bbd9048a5c47f9ed191b0470d0ff6701e102df2f99494c3de7"`
[INFO] [stderr]     Checking const-concat v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] error[E0658]: unions in const fn are unstable
[INFO] [stderr]   --> src/lib.rs:10:5
[INFO] [stderr]    |
[INFO] [stderr] 10 |     Transmute { from }.to
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: for more information, see https://github.com/rust-lang/rust/issues/51909
[INFO] [stderr]    = help: add `#![feature(const_fn_union)]` to the crate attributes to enable
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0658`.
[INFO] [stderr] error: could not compile `const-concat`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error[E0658]: unions in const fn are unstable
[INFO] [stderr]   --> src/lib.rs:10:5
[INFO] [stderr]    |
[INFO] [stderr] 10 |     Transmute { from }.to
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: for more information, see https://github.com/rust-lang/rust/issues/51909
[INFO] [stderr]    = help: add `#![feature(const_fn_union)]` to the crate attributes to enable
[INFO] [stderr] 
[INFO] [stderr] error[E0080]: evaluation of constant value failed
[INFO] [stderr]   --> src/lib.rs:44:27
[INFO] [stderr]    |
[INFO] [stderr] 44 |         const_concat!($a, TAIL)
[INFO] [stderr]    |                           ^^^^ referenced constant has errors
[INFO] [stderr] ...
[INFO] [stderr] 57 |         const GREETING: &str = const_concat!(SALUTATION, ", ", TARGET, "!");
[INFO] [stderr]    |                                -------------------------------------------- in this macro invocation
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 2 previous errors
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0080, E0658.
[INFO] [stderr] For more information about an error, try `rustc --explain E0080`.
[INFO] [stderr] error: could not compile `const-concat`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "f09ff81781e392bbd9048a5c47f9ed191b0470d0ff6701e102df2f99494c3de7"`
[INFO] running `"docker" "rm" "-f" "f09ff81781e392bbd9048a5c47f9ed191b0470d0ff6701e102df2f99494c3de7"`
[INFO] [stdout] f09ff81781e392bbd9048a5c47f9ed191b0470d0ff6701e102df2f99494c3de7