[INFO] crate slice 0.0.4 is already in cache [INFO] extracting crate slice 0.0.4 into work/ex/beta-1.37-6/sources/1.36.0/reg/slice/0.0.4 [INFO] extracting crate slice 0.0.4 into work/ex/beta-1.37-6/sources/beta-2019-07-23/reg/slice/0.0.4 [INFO] validating manifest of slice-0.0.4 on toolchain 1.36.0 [INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "read-manifest" "--manifest-path" "Cargo.toml"` [INFO] validating manifest of slice-0.0.4 on toolchain beta-2019-07-23 [INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "read-manifest" "--manifest-path" "Cargo.toml"` [INFO] started frobbing slice-0.0.4 [INFO] finished frobbing slice-0.0.4 [INFO] frobbed toml for slice-0.0.4 written to work/ex/beta-1.37-6/sources/1.36.0/reg/slice/0.0.4/Cargo.toml [INFO] started frobbing slice-0.0.4 [INFO] finished frobbing slice-0.0.4 [INFO] frobbed toml for slice-0.0.4 written to work/ex/beta-1.37-6/sources/beta-2019-07-23/reg/slice/0.0.4/Cargo.toml [INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"` [INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"` [INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"` [INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "fetch" "--locked" "--manifest-path" "Cargo.toml"` [INFO] testing slice-0.0.4 against 1.36.0 for beta-1.37-6 [INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-2/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/reg/slice/0.0.4:/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" "+1.36.0" "build" "--frozen"` [INFO] [stdout] 1a3aad2dd83bf91804d3ca5e9f87ec7cf3a72d8b92cb50236f0c8c70457f1c5c [INFO] running `"docker" "start" "-a" "1a3aad2dd83bf91804d3ca5e9f87ec7cf3a72d8b92cb50236f0c8c70457f1c5c"` [INFO] [stderr] Compiling slice v0.0.4 (/opt/crater/workdir) [INFO] [stderr] Finished dev [unoptimized + debuginfo] target(s) in 0.53s [INFO] running `"docker" "inspect" "1a3aad2dd83bf91804d3ca5e9f87ec7cf3a72d8b92cb50236f0c8c70457f1c5c"` [INFO] running `"docker" "rm" "-f" "1a3aad2dd83bf91804d3ca5e9f87ec7cf3a72d8b92cb50236f0c8c70457f1c5c"` [INFO] [stdout] 1a3aad2dd83bf91804d3ca5e9f87ec7cf3a72d8b92cb50236f0c8c70457f1c5c [INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-2/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/reg/slice/0.0.4:/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" "+1.36.0" "test" "--frozen" "--no-run"` [INFO] [stdout] 99ea1e60dbcafa15bad8af5047d5c6ebe0246b244570820a6abef27527f9a559 [INFO] running `"docker" "start" "-a" "99ea1e60dbcafa15bad8af5047d5c6ebe0246b244570820a6abef27527f9a559"` [INFO] [stderr] Compiling slice v0.0.4 (/opt/crater/workdir) [INFO] [stderr] Finished dev [unoptimized + debuginfo] target(s) in 0.61s [INFO] running `"docker" "inspect" "99ea1e60dbcafa15bad8af5047d5c6ebe0246b244570820a6abef27527f9a559"` [INFO] running `"docker" "rm" "-f" "99ea1e60dbcafa15bad8af5047d5c6ebe0246b244570820a6abef27527f9a559"` [INFO] [stdout] 99ea1e60dbcafa15bad8af5047d5c6ebe0246b244570820a6abef27527f9a559 [INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-2/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/reg/slice/0.0.4:/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" "+1.36.0" "test" "--frozen"` [INFO] [stdout] 95d529f2fcbbabe568b210d4356ccbe26a38ff94d30830864e7eb99ab8ba163d [INFO] running `"docker" "start" "-a" "95d529f2fcbbabe568b210d4356ccbe26a38ff94d30830864e7eb99ab8ba163d"` [INFO] [stderr] Finished dev [unoptimized + debuginfo] target(s) in 0.02s [INFO] [stderr] Running /opt/crater/target/debug/deps/slice-b80db72a3d2bace2 [INFO] [stdout] [INFO] [stdout] running 0 tests [INFO] [stdout] [INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out [INFO] [stdout] [INFO] [stderr] Doc-tests slice [INFO] [stdout] [INFO] [stdout] running 2 tests [INFO] [stdout] test src/lib.rs - IoSlice (line 56) ... FAILED [INFO] [stdout] test src/lib.rs - (line 10) ... FAILED [INFO] [stdout] [INFO] [stdout] failures: [INFO] [stdout] [INFO] [stdout] ---- src/lib.rs - IoSlice (line 56) stdout ---- [INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `std::ops::Try`) [INFO] [stdout] --> src/lib.rs:60:14 [INFO] [stdout] | [INFO] [stdout] 7 | let source = File::open("/home/annie/data.png")?; [INFO] [stdout] | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()` [INFO] [stdout] | [INFO] [stdout] = help: the trait `std::ops::Try` is not implemented for `()` [INFO] [stdout] = note: required by `std::ops::Try::from_error` [INFO] [stdout] [INFO] [stdout] error: aborting due to previous error [INFO] [stdout] [INFO] [stdout] For more information about this error, try `rustc --explain E0277`. [INFO] [stdout] thread 'src/lib.rs - IoSlice (line 56)' panicked at 'couldn't compile the test', src/librustdoc/test.rs:319:13 [INFO] [stdout] stack backtrace: [INFO] [stdout] 0: 0x7f1214641823 - std::sys::unix::backtrace::tracing::imp::unwind_backtrace::h6485381528590a55 [INFO] [stdout] at src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:39 [INFO] [stdout] 1: 0x7f12146394cb - std::sys_common::backtrace::_print::h49a82ae9552e35c7 [INFO] [stdout] at src/libstd/sys_common/backtrace.rs:71 [INFO] [stdout] 2: 0x7f121463da56 - std::panicking::default_hook::{{closure}}::he20974adbefcc046 [INFO] [stdout] at src/libstd/sys_common/backtrace.rs:59 [INFO] [stdout] at src/libstd/panicking.rs:197 [INFO] [stdout] 3: 0x7f121463d77e - std::panicking::default_hook::he4af6af4ac7fef7b [INFO] [stdout] at src/libstd/panicking.rs:208 [INFO] [stdout] 4: 0x7f121463e15f - std::panicking::rust_panic_with_hook::h057ff03eb4c8000f [INFO] [stdout] at src/libstd/panicking.rs:474 [INFO] [stdout] 5: 0x559ff19d9784 - std::panicking::begin_panic::h2203228e86eb91b5 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/panicking.rs:408 [INFO] [stdout] 6: 0x559ff19cf68f - rustdoc::test::run_test::h29a20600da33f74f [INFO] [stdout] at src/librustdoc/test.rs:319 [INFO] [stdout] 7: 0x559ff19c37c9 - core::ops::function::FnOnce::call_once{{vtable.shim}}::h84ad3bdb52e265e9 [INFO] [stdout] at src/librustdoc/test.rs:715 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libcore/ops/function.rs:231 [INFO] [stdout] 8: 0x7f1215bc4b7e - as core::ops::function::FnOnce>::call_once::h6b004fa8f4fc1608 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/liballoc/boxed.rs:704 [INFO] [stdout] 9: 0x7f1215bc4b7e - as core::ops::function::FnOnce>::call_once::h6b004fa8f4fc1608 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/liballoc/boxed.rs:704 [INFO] [stdout] 10: 0x7f121464f169 - __rust_maybe_catch_panic [INFO] [stdout] at src/libpanic_unwind/lib.rs:85 [INFO] [stdout] 11: 0x7f1215bdff87 - test::run_test::run_test_inner::{{closure}}::h9a4d23c41d058d37 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/panicking.rs:272 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/panic.rs:394 [INFO] [stdout] at src/libtest/lib.rs:1468 [INFO] [stdout] 12: 0x7f1215bb99a4 - std::sys_common::backtrace::__rust_begin_short_backtrace::h3765d76361a33ff7 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/sys_common/backtrace.rs:136 [INFO] [stdout] 13: 0x7f1215bbda54 - std::panicking::try::do_call::h6f86e980b52f74d5 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/thread/mod.rs:470 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/panic.rs:315 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/panicking.rs:293 [INFO] [stdout] 14: 0x7f121464f169 - __rust_maybe_catch_panic [INFO] [stdout] at src/libpanic_unwind/lib.rs:85 [INFO] [stdout] 15: 0x7f1215bbe551 - core::ops::function::FnOnce::call_once{{vtable.shim}}::h760b8a2b155f54c3 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/panicking.rs:272 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/panic.rs:394 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/thread/mod.rs:469 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libcore/ops/function.rs:231 [INFO] [stdout] 16: 0x7f121462036e - as core::ops::function::FnOnce>::call_once::h805c3cc89d534c05 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/liballoc/boxed.rs:704 [INFO] [stdout] 17: 0x7f121464dddf - std::sys::unix::thread::Thread::new::thread_start::h6f10b78f26c98dc6 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/liballoc/boxed.rs:704 [INFO] [stdout] at src/libstd/sys_common/thread.rs:13 [INFO] [stdout] at src/libstd/sys/unix/thread.rs:79 [INFO] [stdout] 18: 0x7f12141b74a3 - start_thread [INFO] [stdout] 19: 0x7f1213ce2d0e - __clone [INFO] [stdout] 20: 0x0 - [INFO] [stdout] [INFO] [stdout] ---- src/lib.rs - (line 10) stdout ---- [INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `std::ops::Try`) [INFO] [stdout] --> src/lib.rs:14:14 [INFO] [stdout] | [INFO] [stdout] 7 | let source = File::open("/home/annie/data.png")?; [INFO] [stdout] | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()` [INFO] [stdout] | [INFO] [stdout] = help: the trait `std::ops::Try` is not implemented for `()` [INFO] [stdout] = note: required by `std::ops::Try::from_error` [INFO] [stdout] [INFO] [stdout] error: aborting due to previous error [INFO] [stdout] [INFO] [stdout] For more information about this error, try `rustc --explain E0277`. [INFO] [stdout] thread 'src/lib.rs - (line 10)' panicked at 'couldn't compile the test', src/librustdoc/test.rs:319:13 [INFO] [stdout] stack backtrace: [INFO] [stdout] 0: 0x7f1214641823 - std::sys::unix::backtrace::tracing::imp::unwind_backtrace::h6485381528590a55 [INFO] [stdout] at src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:39 [INFO] [stdout] 1: 0x7f12146394cb - std::sys_common::backtrace::_print::h49a82ae9552e35c7 [INFO] [stdout] at src/libstd/sys_common/backtrace.rs:71 [INFO] [stdout] 2: 0x7f121463da56 - std::panicking::default_hook::{{closure}}::he20974adbefcc046 [INFO] [stdout] at src/libstd/sys_common/backtrace.rs:59 [INFO] [stdout] at src/libstd/panicking.rs:197 [INFO] [stdout] 3: 0x7f121463d77e - std::panicking::default_hook::he4af6af4ac7fef7b [INFO] [stdout] at src/libstd/panicking.rs:208 [INFO] [stdout] 4: 0x7f121463e15f - std::panicking::rust_panic_with_hook::h057ff03eb4c8000f [INFO] [stdout] at src/libstd/panicking.rs:474 [INFO] [stdout] 5: 0x559ff19d9784 - std::panicking::begin_panic::h2203228e86eb91b5 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/panicking.rs:408 [INFO] [stdout] 6: 0x559ff19cf68f - rustdoc::test::run_test::h29a20600da33f74f [INFO] [stdout] at src/librustdoc/test.rs:319 [INFO] [stdout] 7: 0x559ff19c37c9 - core::ops::function::FnOnce::call_once{{vtable.shim}}::h84ad3bdb52e265e9 [INFO] [stdout] at src/librustdoc/test.rs:715 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libcore/ops/function.rs:231 [INFO] [stdout] 8: 0x7f1215bc4b7e - as core::ops::function::FnOnce>::call_once::h6b004fa8f4fc1608 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/liballoc/boxed.rs:704 [INFO] [stdout] 9: 0x7f1215bc4b7e - as core::ops::function::FnOnce>::call_once::h6b004fa8f4fc1608 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/liballoc/boxed.rs:704 [INFO] [stdout] 10: 0x7f121464f169 - __rust_maybe_catch_panic [INFO] [stdout] at src/libpanic_unwind/lib.rs:85 [INFO] [stdout] 11: 0x7f1215bdff87 - test::run_test::run_test_inner::{{closure}}::h9a4d23c41d058d37 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/panicking.rs:272 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/panic.rs:394 [INFO] [stdout] at src/libtest/lib.rs:1468 [INFO] [stdout] 12: 0x7f1215bb99a4 - std::sys_common::backtrace::__rust_begin_short_backtrace::h3765d76361a33ff7 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/sys_common/backtrace.rs:136 [INFO] [stdout] 13: 0x7f1215bbda54 - std::panicking::try::do_call::h6f86e980b52f74d5 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/thread/mod.rs:470 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/panic.rs:315 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/panicking.rs:293 [INFO] [stdout] 14: 0x7f121464f169 - __rust_maybe_catch_panic [INFO] [stdout] at src/libpanic_unwind/lib.rs:85 [INFO] [stdout] 15: 0x7f1215bbe551 - core::ops::function::FnOnce::call_once{{vtable.shim}}::h760b8a2b155f54c3 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/panicking.rs:272 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/panic.rs:394 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libstd/thread/mod.rs:469 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/libcore/ops/function.rs:231 [INFO] [stdout] 16: 0x7f121462036e - as core::ops::function::FnOnce>::call_once::h805c3cc89d534c05 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/liballoc/boxed.rs:704 [INFO] [stdout] 17: 0x7f121464dddf - std::sys::unix::thread::Thread::new::thread_start::h6f10b78f26c98dc6 [INFO] [stdout] at /rustc/a53f9df32fbb0b5f4382caaad8f1a46f36ea887c/src/liballoc/boxed.rs:704 [INFO] [stdout] at src/libstd/sys_common/thread.rs:13 [INFO] [stdout] at src/libstd/sys/unix/thread.rs:79 [INFO] [stdout] 18: 0x7f12141b74a3 - start_thread [INFO] [stdout] 19: 0x7f1213ce2d0e - __clone [INFO] [stdout] 20: 0x0 - [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] failures: [INFO] [stdout] src/lib.rs - (line 10) [INFO] [stdout] src/lib.rs - IoSlice (line 56) [INFO] [stdout] [INFO] [stdout] test result: FAILED. 0 passed; 2 failed; 0 ignored; 0 measured; 0 filtered out [INFO] [stdout] [INFO] [stderr] error: test failed, to rerun pass '--doc' [INFO] running `"docker" "inspect" "95d529f2fcbbabe568b210d4356ccbe26a38ff94d30830864e7eb99ab8ba163d"` [INFO] running `"docker" "rm" "-f" "95d529f2fcbbabe568b210d4356ccbe26a38ff94d30830864e7eb99ab8ba163d"` [INFO] [stdout] 95d529f2fcbbabe568b210d4356ccbe26a38ff94d30830864e7eb99ab8ba163d