[INFO] crate compiler_builtins 0.1.19 is already in cache
[INFO] extracting crate compiler_builtins 0.1.19 into work/ex/beta-1.38-1/sources/1.37.0/reg/compiler_builtins/0.1.19
[INFO] extracting crate compiler_builtins 0.1.19 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/compiler_builtins/0.1.19
[INFO] validating manifest of compiler_builtins-0.1.19 on toolchain 1.37.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of compiler_builtins-0.1.19 on toolchain beta-2019-08-13
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing compiler_builtins-0.1.19
[INFO] removed 1 missing examples
[INFO] finished frobbing compiler_builtins-0.1.19
[INFO] frobbed toml for compiler_builtins-0.1.19 written to work/ex/beta-1.38-1/sources/1.37.0/reg/compiler_builtins/0.1.19/Cargo.toml
[INFO] started frobbing compiler_builtins-0.1.19
[INFO] removed 1 missing examples
[INFO] finished frobbing compiler_builtins-0.1.19
[INFO] frobbed toml for compiler_builtins-0.1.19 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/compiler_builtins/0.1.19/Cargo.toml
[INFO] crate compiler_builtins-0.1.19 already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing compiler_builtins-0.1.19 against 1.37.0 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-1/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/compiler_builtins/0.1.19:/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=warn" "-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" "+1.37.0" "build" "--frozen"`
[INFO] [stdout] 79c027e14d6e7d407421c95c49cfa01a04b7a3cdb65bb20a098daec272af2d16
[INFO] running `"docker" "start" "-a" "79c027e14d6e7d407421c95c49cfa01a04b7a3cdb65bb20a098daec272af2d16"`
[INFO] [stderr] warning: An explicit [[example]] section is specified in Cargo.toml which currently
[INFO] [stderr] disables Cargo from automatically inferring other example targets.
[INFO] [stderr] This inference behavior will change in the Rust 2018 edition and the following
[INFO] [stderr] files will be included as a example target:
[INFO] [stderr] 
[INFO] [stderr] * /opt/crater/workdir/examples/intrinsics.rs
[INFO] [stderr] 
[INFO] [stderr] This is likely to break cargo build or cargo test as these files may not be
[INFO] [stderr] ready to be compiled as a example target today. You can future-proof yourself
[INFO] [stderr] and disable this warning by adding `autoexamples = false` to your [package]
[INFO] [stderr] section. You may also move the files to a location where Cargo would not
[INFO] [stderr] automatically infer them to be a target, such as in subfolders.
[INFO] [stderr] 
[INFO] [stderr] For more information on this warning you can consult
[INFO] [stderr] https://github.com/rust-lang/cargo/issues/5330
[INFO] [stderr]    Compiling compiler_builtins v0.1.19 (/opt/crater/workdir)
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]   --> src/lib.rs:13:1
[INFO] [stderr]    |
[INFO] [stderr] 13 | #![feature(asm)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]   --> src/lib.rs:14:1
[INFO] [stderr]    |
[INFO] [stderr] 14 | #![feature(compiler_builtins)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]   --> src/lib.rs:15:1
[INFO] [stderr]    |
[INFO] [stderr] 15 | #![feature(core_intrinsics)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]   --> src/lib.rs:16:1
[INFO] [stderr]    |
[INFO] [stderr] 16 | #![feature(naked_functions)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]   --> src/lib.rs:17:1
[INFO] [stderr]    |
[INFO] [stderr] 17 | #![feature(repr_simd)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]   --> src/lib.rs:18:1
[INFO] [stderr]    |
[INFO] [stderr] 18 | #![feature(abi_unadjusted)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]   --> src/lib.rs:19:1
[INFO] [stderr]    |
[INFO] [stderr] 19 | #![feature(linkage)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]   --> src/lib.rs:20:1
[INFO] [stderr]    |
[INFO] [stderr] 20 | #![feature(lang_items)]
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]   --> src/lib.rs:23:44
[INFO] [stderr]    |
[INFO] [stderr] 23 | #![cfg_attr(feature = "compiler-builtins", feature(staged_api))]
[INFO] [stderr]    |                                            ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 9 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `compiler_builtins`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "79c027e14d6e7d407421c95c49cfa01a04b7a3cdb65bb20a098daec272af2d16"`
[INFO] running `"docker" "rm" "-f" "79c027e14d6e7d407421c95c49cfa01a04b7a3cdb65bb20a098daec272af2d16"`
[INFO] [stdout] 79c027e14d6e7d407421c95c49cfa01a04b7a3cdb65bb20a098daec272af2d16