[INFO] crate stm32f072b-disco 0.2.1 is already in cache
[INFO] extracting crate stm32f072b-disco 0.2.1 into work/ex/beta-1.38-1/sources/1.37.0/reg/stm32f072b-disco/0.2.1
[INFO] extracting crate stm32f072b-disco 0.2.1 into work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/stm32f072b-disco/0.2.1
[INFO] validating manifest of stm32f072b-disco-0.2.1 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 stm32f072b-disco-0.2.1 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 stm32f072b-disco-0.2.1
[INFO] finished frobbing stm32f072b-disco-0.2.1
[INFO] frobbed toml for stm32f072b-disco-0.2.1 written to work/ex/beta-1.38-1/sources/1.37.0/reg/stm32f072b-disco/0.2.1/Cargo.toml
[INFO] started frobbing stm32f072b-disco-0.2.1
[INFO] finished frobbing stm32f072b-disco-0.2.1
[INFO] frobbed toml for stm32f072b-disco-0.2.1 written to work/ex/beta-1.38-1/sources/beta-2019-08-13/reg/stm32f072b-disco/0.2.1/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[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 stm32f072b-disco-0.2.1 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-3/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/reg/stm32f072b-disco/0.2.1:/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] a24d05a1861e7cd6f43ac3c155bd44d8c65d1459c8df93b7ae663a029b273956
[INFO] running `"docker" "start" "-a" "a24d05a1861e7cd6f43ac3c155bd44d8c65d1459c8df93b7ae663a029b273956"`
[INFO] [stderr]    Compiling typenum v1.10.0
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling rand_core v0.4.2
[INFO] [stderr]    Compiling stable_deref_trait v1.1.1
[INFO] [stderr]    Compiling vcell v0.1.0
[INFO] [stderr]    Compiling cortex-m-rt v0.6.10
[INFO] [stderr]    Compiling cortex-m v0.6.1
[INFO] [stderr]    Compiling stm32f0 v0.7.1
[INFO] [stderr] error[E0463]: can't find crate for `core`
[INFO] [stderr]   |
[INFO] [stderr]   = note: the `thumbv6m-none-eabi` target may not be installed
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0463`.
[INFO] [stderr] error: Could not compile `stable_deref_trait`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error[E0463]: can't find crate for `core`
[INFO] [stderr]   |
[INFO] [stderr]   = note: the `thumbv6m-none-eabi` target may not be installed
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0463`.
[INFO] [stderr] error: Could not compile `vcell`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "a24d05a1861e7cd6f43ac3c155bd44d8c65d1459c8df93b7ae663a029b273956"`
[INFO] running `"docker" "rm" "-f" "a24d05a1861e7cd6f43ac3c155bd44d8c65d1459c8df93b7ae663a029b273956"`
[INFO] [stdout] a24d05a1861e7cd6f43ac3c155bd44d8c65d1459c8df93b7ae663a029b273956