[INFO] fetching crate db-core 0.2.1...
[INFO] checking db-core-0.2.1 against master#9610dfe5a9a731ced1ea4923ecbd0c57fe367898 for beta-170-4
[INFO] extracting crate db-core 0.2.1 into /workspace/builds/worker-4-tc1/source
[INFO] validating manifest of crates.io crate db-core 0.2.1 on toolchain 9610dfe5a9a731ced1ea4923ecbd0c57fe367898
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+9610dfe5a9a731ced1ea4923ecbd0c57fe367898" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate db-core 0.2.1
[INFO] finished tweaking crates.io crate db-core 0.2.1
[INFO] tweaked toml for crates.io crate db-core 0.2.1 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" __CARGO_TEST_CHANNEL_OVERRIDE_DO_NOT_USE_THIS="nightly" "/workspace/cargo-home/bin/cargo" "+9610dfe5a9a731ced1ea4923ecbd0c57fe367898" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+9610dfe5a9a731ced1ea4923ecbd0c57fe367898" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/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@sha256:19e73879b68f455e41552ea35293514db52ea292d993f571636dbffedb77a1ee" "/opt/rustwide/cargo-home/bin/cargo" "+9610dfe5a9a731ced1ea4923ecbd0c57fe367898" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2f98b2d2ad88546d8746ec0ea4a4567a79b7bb7fafea6e0fccf175e52984c00c
[INFO] running `Command { std: "docker" "start" "-a" "2f98b2d2ad88546d8746ec0ea4a4567a79b7bb7fafea6e0fccf175e52984c00c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2f98b2d2ad88546d8746ec0ea4a4567a79b7bb7fafea6e0fccf175e52984c00c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2f98b2d2ad88546d8746ec0ea4a4567a79b7bb7fafea6e0fccf175e52984c00c", kill_on_drop: false }`
[INFO] [stdout] 2f98b2d2ad88546d8746ec0ea4a4567a79b7bb7fafea6e0fccf175e52984c00c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/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=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-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@sha256:19e73879b68f455e41552ea35293514db52ea292d993f571636dbffedb77a1ee" "/opt/rustwide/cargo-home/bin/cargo" "+9610dfe5a9a731ced1ea4923ecbd0c57fe367898" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e5f293b8a71afe1e95ede7ab774aee437e5110320d5b9085874054f2146bffb1
[INFO] running `Command { std: "docker" "start" "-a" "e5f293b8a71afe1e95ede7ab774aee437e5110320d5b9085874054f2146bffb1", kill_on_drop: false }`
[INFO] [stderr]    Compiling log v0.4.18
[INFO] [stderr]     Checking ppv-lite86 v0.2.17
[INFO] [stderr]     Checking getrandom v0.2.9
[INFO] [stderr]     Checking fs2 v0.4.3
[INFO] [stderr]     Checking rand_core v0.6.4
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]     Checking db-core v0.2.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: use of deprecated type alias `std::alloc::LayoutErr`: Name does not follow std convention, use LayoutError
[INFO] [stdout]    --> src/common/errors.rs:219:17
[INFO] [stdout]     |
[INFO] [stdout] 219 |     std::alloc::LayoutErr, IncorrectLayout, layout_err,
[INFO] [stdout]     |                 ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated type alias `std::alloc::LayoutErr`: Name does not follow std convention, use LayoutError
[INFO] [stdout]    --> src/common/errors.rs:209:79
[INFO] [stdout]     |
[INFO] [stdout] 209 |     IncorrectLayout             , incorrect_layout              , std::alloc::LayoutErr,
[INFO] [stdout]     |                                                                               ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated function `std::sync::atomic::spin_loop_hint`: use hint::spin_loop instead
[INFO] [stdout]    --> src/common/intercom.rs:202:33
[INFO] [stdout]     |
[INFO] [stdout] 202 |             core::sync::atomic::spin_loop_hint();
[INFO] [stdout]     |                                 ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking rand v0.8.5
[INFO] [stdout] warning: use of deprecated method `std::sync::atomic::AtomicUsize::compare_and_swap`: Use `compare_exchange` or `compare_exchange_weak` instead
[INFO] [stdout]    --> src/log_mgr/buf.rs:112:52
[INFO] [stdout]     |
[INFO] [stdout] 112 |             let cur_acq_size = self.acquire_size.0.compare_and_swap(
[INFO] [stdout]     |                                                    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated method `std::sync::atomic::AtomicUsize::compare_and_swap`: Use `compare_exchange` or `compare_exchange_weak` instead
[INFO] [stdout]    --> src/log_mgr/buf.rs:182:52
[INFO] [stdout]     |
[INFO] [stdout] 182 |             let cur_acq_size = self.acquire_size.0.compare_and_swap(
[INFO] [stdout]     |                                                    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/storage/datastore.rs:445:29
[INFO] [stdout]     |
[INFO] [stdout] 445 |     fn add_fi_blocks(&self, mut block_id: &mut BlockId, fi_block_num: usize, stub_pin: &AtomicU64, f: &std::fs::File) -> Result<(), Error> {
[INFO] [stdout]     |                             ----^^^^^^^^
[INFO] [stdout]     |                             |
[INFO] [stdout]     |                             help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/storage/datastore.rs:863:13
[INFO] [stdout]     |
[INFO] [stdout] 863 |         let mut desc = xlock.get_mut(&file_id).unwrap();
[INFO] [stdout]     |             ----^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/storage/datastore.rs:869:13
[INFO] [stdout]     |
[INFO] [stdout] 869 |         let mut desc = xlock.get_mut(&file_id).unwrap();
[INFO] [stdout]     |             ----^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/storage/block_driver.rs:731:26
[INFO] [stdout]     |
[INFO] [stdout] 731 |     pub fn replay(&self, mut rs: &mut ReplayState, data: &[u8]) -> Result<(), Error> {
[INFO] [stdout]     |                          ----^^
[INFO] [stdout]     |                          |
[INFO] [stdout]     |                          help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `write_ready` is never read
[INFO] [stdout]   --> src/buf_mgr/buf_writer.rs:32:5
[INFO] [stdout]    |
[INFO] [stdout] 29 | pub struct BufWriter {
[INFO] [stdout]    |            --------- field in this struct
[INFO] [stdout] ...
[INFO] [stdout] 32 |     write_ready:        SyncNotification<usize>,
[INFO] [stdout]    |     ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `BufWriter` has a derived impl for the trait `Clone`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `wait_time` and `wait_count` are never read
[INFO] [stdout]    --> src/log_mgr/buf.rs:244:5
[INFO] [stdout]     |
[INFO] [stdout] 243 | pub struct Metrics {
[INFO] [stdout]     |            ------- fields in this struct
[INFO] [stdout] 244 |     wait_time:   u64,
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout] 245 |     wait_count:  u64,
[INFO] [stdout]     |     ^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `Metrics` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `set_extent_bit` is never used
[INFO] [stdout]    --> src/block_mgr/free_info.rs:121:12
[INFO] [stdout]     |
[INFO] [stdout] 36  | impl FreeInfo {
[INFO] [stdout]     | ------------- method in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 121 |     pub fn set_extent_bit(&self, file_id: u16, extent_id: u16, set: bool) -> Result<(), Error> {
[INFO] [stdout]     |            ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `used_iter` is never used
[INFO] [stdout]    --> src/block_mgr/free_info.rs:321:12
[INFO] [stdout]     |
[INFO] [stdout] 305 | impl FiData {
[INFO] [stdout]     | ----------- method in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 321 |     pub fn used_iter(&self) -> FiDataIter {
[INFO] [stdout]     |            ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `delete_entry` is never used
[INFO] [stdout]    --> src/block_mgr/block.rs:276:12
[INFO] [stdout]     |
[INFO] [stdout] 131 | impl<'a> DataBlock<'a> {
[INFO] [stdout]     | ---------------------- method in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 276 |     pub fn delete_entry(&mut self, entry_id: u16) {
[INFO] [stdout]     |            ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `mark_extent_full` and `set_free_info_free` are never used
[INFO] [stdout]    --> src/block_mgr/allocator.rs:93:12
[INFO] [stdout]     |
[INFO] [stdout] 37  | impl BlockAllocator {
[INFO] [stdout]     | ------------------- methods in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 93  |     pub fn mark_extent_full(&self, file_id: u16, extent_id: u16) -> Result<(), Error> {
[INFO] [stdout]     |            ^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 127 |     pub fn set_free_info_free(&self, block_id: &BlockId) -> Result<(), Error> {
[INFO] [stdout]     |            ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a value that implements `Copy` does nothing
[INFO] [stdout]    --> src/storage/datastore.rs:764:9
[INFO] [stdout]     |
[INFO] [stdout] 764 |         drop(v);
[INFO] [stdout]     |         ^^^^^-^
[INFO] [stdout]     |              |
[INFO] [stdout]     |              argument has type `()`
[INFO] [stdout]     |
[INFO] [stdout]     = note: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]     = note: `#[warn(dropping_copy_types)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 16 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated type alias `std::alloc::LayoutErr`: Name does not follow std convention, use LayoutError
[INFO] [stdout]    --> src/common/errors.rs:219:17
[INFO] [stdout]     |
[INFO] [stdout] 219 |     std::alloc::LayoutErr, IncorrectLayout, layout_err,
[INFO] [stdout]     |                 ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated type alias `std::alloc::LayoutErr`: Name does not follow std convention, use LayoutError
[INFO] [stdout]    --> src/common/errors.rs:209:79
[INFO] [stdout]     |
[INFO] [stdout] 209 |     IncorrectLayout             , incorrect_layout              , std::alloc::LayoutErr,
[INFO] [stdout]     |                                                                               ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated function `std::sync::atomic::spin_loop_hint`: use hint::spin_loop instead
[INFO] [stdout]    --> src/common/intercom.rs:202:33
[INFO] [stdout]     |
[INFO] [stdout] 202 |             core::sync::atomic::spin_loop_hint();
[INFO] [stdout]     |                                 ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated method `std::sync::atomic::AtomicUsize::compare_and_swap`: Use `compare_exchange` or `compare_exchange_weak` instead
[INFO] [stdout]    --> src/log_mgr/buf.rs:112:52
[INFO] [stdout]     |
[INFO] [stdout] 112 |             let cur_acq_size = self.acquire_size.0.compare_and_swap(
[INFO] [stdout]     |                                                    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated method `std::sync::atomic::AtomicUsize::compare_and_swap`: Use `compare_exchange` or `compare_exchange_weak` instead
[INFO] [stdout]    --> src/log_mgr/buf.rs:182:52
[INFO] [stdout]     |
[INFO] [stdout] 182 |             let cur_acq_size = self.acquire_size.0.compare_and_swap(
[INFO] [stdout]     |                                                    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/storage/datastore.rs:445:29
[INFO] [stdout]     |
[INFO] [stdout] 445 |     fn add_fi_blocks(&self, mut block_id: &mut BlockId, fi_block_num: usize, stub_pin: &AtomicU64, f: &std::fs::File) -> Result<(), Error> {
[INFO] [stdout]     |                             ----^^^^^^^^
[INFO] [stdout]     |                             |
[INFO] [stdout]     |                             help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/storage/datastore.rs:863:13
[INFO] [stdout]     |
[INFO] [stdout] 863 |         let mut desc = xlock.get_mut(&file_id).unwrap();
[INFO] [stdout]     |             ----^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/storage/datastore.rs:869:13
[INFO] [stdout]     |
[INFO] [stdout] 869 |         let mut desc = xlock.get_mut(&file_id).unwrap();
[INFO] [stdout]     |             ----^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/storage/block_driver.rs:731:26
[INFO] [stdout]     |
[INFO] [stdout] 731 |     pub fn replay(&self, mut rs: &mut ReplayState, data: &[u8]) -> Result<(), Error> {
[INFO] [stdout]     |                          ----^^
[INFO] [stdout]     |                          |
[INFO] [stdout]     |                          help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `write_ready` is never read
[INFO] [stdout]   --> src/buf_mgr/buf_writer.rs:32:5
[INFO] [stdout]    |
[INFO] [stdout] 29 | pub struct BufWriter {
[INFO] [stdout]    |            --------- field in this struct
[INFO] [stdout] ...
[INFO] [stdout] 32 |     write_ready:        SyncNotification<usize>,
[INFO] [stdout]    |     ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `BufWriter` has a derived impl for the trait `Clone`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `wait_time` and `wait_count` are never read
[INFO] [stdout]    --> src/log_mgr/buf.rs:244:5
[INFO] [stdout]     |
[INFO] [stdout] 243 | pub struct Metrics {
[INFO] [stdout]     |            ------- fields in this struct
[INFO] [stdout] 244 |     wait_time:   u64,
[INFO] [stdout]     |     ^^^^^^^^^
[INFO] [stdout] 245 |     wait_count:  u64,
[INFO] [stdout]     |     ^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `Metrics` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `mark_extent_full` is never used
[INFO] [stdout]   --> src/block_mgr/allocator.rs:93:12
[INFO] [stdout]    |
[INFO] [stdout] 37 | impl BlockAllocator {
[INFO] [stdout]    | ------------------- method in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 93 |     pub fn mark_extent_full(&self, file_id: u16, extent_id: u16) -> Result<(), Error> {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a value that implements `Copy` does nothing
[INFO] [stdout]    --> src/storage/datastore.rs:764:9
[INFO] [stdout]     |
[INFO] [stdout] 764 |         drop(v);
[INFO] [stdout]     |         ^^^^^-^
[INFO] [stdout]     |              |
[INFO] [stdout]     |              argument has type `()`
[INFO] [stdout]     |
[INFO] [stdout]     = note: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]     = note: `#[warn(dropping_copy_types)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]     --> src/block_mgr/block.rs:1128:9
[INFO] [stdout]      |
[INFO] [stdout] 1128 |         &mut entry4_buf.copy_from_slice(entry.data);
[INFO] [stdout]      |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]      |
[INFO] [stdout]      = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]      |
[INFO] [stdout] 1128 |         let _ = &mut entry4_buf.copy_from_slice(entry.data);
[INFO] [stdout]      |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 14 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.60s
[INFO] running `Command { std: "docker" "inspect" "e5f293b8a71afe1e95ede7ab774aee437e5110320d5b9085874054f2146bffb1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e5f293b8a71afe1e95ede7ab774aee437e5110320d5b9085874054f2146bffb1", kill_on_drop: false }`
[INFO] [stdout] e5f293b8a71afe1e95ede7ab774aee437e5110320d5b9085874054f2146bffb1
