[INFO] cloning repository https://github.com/gmorenz/photon_correlation [INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/gmorenz/photon_correlation" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgmorenz%2Fphoton_correlation", kill_on_drop: false }` [INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgmorenz%2Fphoton_correlation'... [INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }` [INFO] [stdout] 2cbe29b6cb8f06abea83918538993f30edfba4c0 [INFO] checking gmorenz/photon_correlation against master#6f40082313d8374bdf962aba943a712d5322fae6 for pr-117967 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgmorenz%2Fphoton_correlation" "/workspace/builds/worker-0-tc1/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc1/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/gmorenz/photon_correlation on toolchain 6f40082313d8374bdf962aba943a712d5322fae6 [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+6f40082313d8374bdf962aba943a712d5322fae6" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/gmorenz/photon_correlation [INFO] finished tweaking git repo https://github.com/gmorenz/photon_correlation [INFO] tweaked toml for git repo https://github.com/gmorenz/photon_correlation written to /workspace/builds/worker-0-tc1/source/Cargo.toml [INFO] crate git repo https://github.com/gmorenz/photon_correlation already has a lockfile, it will not be regenerated [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+6f40082313d8374bdf962aba943a712d5322fae6" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] Blocking waiting for file lock on package cache [INFO] [stderr] Blocking waiting for file lock on package cache [ERROR] error running command: no output for 300 seconds [ERROR] this task or one of its parent failed! [ERROR] no output for 300 seconds [ERROR] note: run with `RUST_BACKTRACE=1` to display a backtrace. [INFO] checking gmorenz/photon_correlation against try#57fd74335bb14b59b719dc3cc5bc4257e73f33ce for pr-117967 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgmorenz%2Fphoton_correlation" "/workspace/builds/worker-0-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/gmorenz/photon_correlation on toolchain 57fd74335bb14b59b719dc3cc5bc4257e73f33ce [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+57fd74335bb14b59b719dc3cc5bc4257e73f33ce" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/gmorenz/photon_correlation [INFO] finished tweaking git repo https://github.com/gmorenz/photon_correlation [INFO] tweaked toml for git repo https://github.com/gmorenz/photon_correlation written to /workspace/builds/worker-0-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/gmorenz/photon_correlation already has a lockfile, it will not be regenerated [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+57fd74335bb14b59b719dc3cc5bc4257e73f33ce" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] Blocking waiting for file lock on package cache [INFO] [stderr] Blocking waiting for file lock on package cache [ERROR] error running command: no output for 300 seconds [INFO] checking gmorenz/photon_correlation against try#57fd74335bb14b59b719dc3cc5bc4257e73f33ce for pr-117967 [INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgmorenz%2Fphoton_correlation" "/workspace/builds/worker-0-tc2/source", kill_on_drop: false }` [INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'... [INFO] [stderr] done. [INFO] validating manifest of git repo https://github.com/gmorenz/photon_correlation on toolchain 57fd74335bb14b59b719dc3cc5bc4257e73f33ce [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+57fd74335bb14b59b719dc3cc5bc4257e73f33ce" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }` [INFO] started tweaking git repo https://github.com/gmorenz/photon_correlation [INFO] finished tweaking git repo https://github.com/gmorenz/photon_correlation [INFO] tweaked toml for git repo https://github.com/gmorenz/photon_correlation written to /workspace/builds/worker-0-tc2/source/Cargo.toml [INFO] crate git repo https://github.com/gmorenz/photon_correlation already has a lockfile, it will not be regenerated [INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+57fd74335bb14b59b719dc3cc5bc4257e73f33ce" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }` [INFO] [stderr] Blocking waiting for file lock on package cache [INFO] [stderr] Blocking waiting for file lock on package cache [INFO] [stderr] Downloading crates ... [INFO] [stderr] Downloaded proc-macro2 v0.4.25 [INFO] [stderr] Downloaded libc v0.2.47 [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+57fd74335bb14b59b719dc3cc5bc4257e73f33ce" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }` [INFO] [stdout] d9f4dc5ee309164935d4a77f16a606bde05b3b6adfd9e02e705776d065047a82 [INFO] running `Command { std: "docker" "start" "-a" "d9f4dc5ee309164935d4a77f16a606bde05b3b6adfd9e02e705776d065047a82", kill_on_drop: false }` [INFO] running `Command { std: "docker" "inspect" "d9f4dc5ee309164935d4a77f16a606bde05b3b6adfd9e02e705776d065047a82", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "d9f4dc5ee309164935d4a77f16a606bde05b3b6adfd9e02e705776d065047a82", kill_on_drop: false }` [INFO] [stdout] d9f4dc5ee309164935d4a77f16a606bde05b3b6adfd9e02e705776d065047a82 [INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+57fd74335bb14b59b719dc3cc5bc4257e73f33ce" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }` [INFO] [stdout] 06ab72bb97a8e14d7f248ce7dd85f4090fea1aff1705ed8b44039cd532f84ba4 [INFO] running `Command { std: "docker" "start" "-a" "06ab72bb97a8e14d7f248ce7dd85f4090fea1aff1705ed8b44039cd532f84ba4", kill_on_drop: false }` [INFO] [stderr] Compiling libc v0.2.47 [INFO] [stderr] Compiling proc-macro2 v0.4.25 [INFO] [stderr] Compiling version_check v0.1.5 [INFO] [stderr] Compiling unicode-xid v0.1.0 [INFO] [stderr] Compiling unicode-segmentation v1.2.1 [INFO] [stderr] Checking cfg-if v0.1.6 [INFO] [stderr] Checking unicode-width v0.1.5 [INFO] [stderr] Checking ansi_term v0.11.0 [INFO] [stderr] Checking vec_map v0.8.1 [INFO] [stderr] Checking strsim v0.7.0 [INFO] [stderr] Checking bitflags v1.0.4 [INFO] [stderr] Checking crossbeam-utils v0.6.3 [INFO] [stderr] Checking arrayref v0.3.5 [INFO] [stderr] Checking textwrap v0.10.0 [INFO] [stderr] Compiling heck v0.3.1 [INFO] [stderr] Compiling memchr v2.1.2 [INFO] [stderr] Checking atty v0.2.11 [INFO] [stderr] Checking memmap v0.7.0 [INFO] [stderr] Compiling quote v0.6.10 [INFO] [stderr] Checking clap v2.32.0 [INFO] [stderr] Compiling syn v0.15.26 [INFO] [stderr] Checking nom v4.1.1 [INFO] [stderr] Compiling structopt-derive v0.2.14 [INFO] [stderr] Checking structopt v0.2.14 [INFO] [stderr] Checking photon_correlation v0.1.0 (/opt/rustwide/workdir) [INFO] [stdout] warning: the item `VecDeque` is imported redundantly [INFO] [stdout] --> src/main.rs:203:9 [INFO] [stdout] | [INFO] [stdout] 13 | use std::collections::VecDeque; [INFO] [stdout] | -------------------------- the item `VecDeque` is already imported here [INFO] [stdout] ... [INFO] [stdout] 203 | use std::collections::VecDeque; [INFO] [stdout] | ^^^^^^^^^^^^^^^^^^^^^^^^^^ [INFO] [stdout] | [INFO] [stdout] = note: `#[warn(unused_imports)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: the item `VecDeque` is imported redundantly [INFO] [stdout] --> src/main.rs:241:9 [INFO] [stdout] | [INFO] [stdout] 13 | use std::collections::VecDeque; [INFO] [stdout] | -------------------------- the item `VecDeque` is already imported here [INFO] [stdout] ... [INFO] [stdout] 241 | use std::collections::VecDeque; [INFO] [stdout] | ^^^^^^^^^^^^^^^^^^^^^^^^^^ [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: the item `VecDeque` is imported redundantly [INFO] [stdout] --> src/main.rs:417:9 [INFO] [stdout] | [INFO] [stdout] 13 | use std::collections::VecDeque; [INFO] [stdout] | -------------------------- the item `VecDeque` is already imported here [INFO] [stdout] ... [INFO] [stdout] 417 | use std::collections::VecDeque; [INFO] [stdout] | ^^^^^^^^^^^^^^^^^^^^^^^^^^ [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: the item `VecDeque` is imported redundantly [INFO] [stdout] --> src/main.rs:203:9 [INFO] [stdout] | [INFO] [stdout] 13 | use std::collections::VecDeque; [INFO] [stdout] | -------------------------- the item `VecDeque` is already imported here [INFO] [stdout] ... [INFO] [stdout] 203 | use std::collections::VecDeque; [INFO] [stdout] | ^^^^^^^^^^^^^^^^^^^^^^^^^^ [INFO] [stdout] | [INFO] [stdout] = note: `#[warn(unused_imports)]` on by default [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: the item `VecDeque` is imported redundantly [INFO] [stdout] --> src/main.rs:241:9 [INFO] [stdout] | [INFO] [stdout] 13 | use std::collections::VecDeque; [INFO] [stdout] | -------------------------- the item `VecDeque` is already imported here [INFO] [stdout] ... [INFO] [stdout] 241 | use std::collections::VecDeque; [INFO] [stdout] | ^^^^^^^^^^^^^^^^^^^^^^^^^^ [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: the item `VecDeque` is imported redundantly [INFO] [stdout] --> src/main.rs:417:9 [INFO] [stdout] | [INFO] [stdout] 13 | use std::collections::VecDeque; [INFO] [stdout] | -------------------------- the item `VecDeque` is already imported here [INFO] [stdout] ... [INFO] [stdout] 417 | use std::collections::VecDeque; [INFO] [stdout] | ^^^^^^^^^^^^^^^^^^^^^^^^^^ [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated [INFO] [stdout] --> src/main.rs:565:38 [INFO] [stdout] | [INFO] [stdout] 565 | fn get_output(path: &PathBuf) -> Box { [INFO] [stdout] | ^^^^^^^^^^^^ [INFO] [stdout] | [INFO] [stdout] = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021! [INFO] [stdout] = note: for more information, see [INFO] [stdout] = note: `#[warn(bare_trait_objects)]` on by default [INFO] [stdout] help: use `dyn` [INFO] [stdout] | [INFO] [stdout] 565 | fn get_output(path: &PathBuf) -> Box { [INFO] [stdout] | +++ [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated [INFO] [stdout] --> src/header.rs:138:34 [INFO] [stdout] | [INFO] [stdout] 138 | pub fn write_header(output: &mut std::io::Write, headers: Header) { [INFO] [stdout] | ^^^^^^^^^^^^^^ [INFO] [stdout] | [INFO] [stdout] = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021! [INFO] [stdout] = note: for more information, see [INFO] [stdout] help: use `dyn` [INFO] [stdout] | [INFO] [stdout] 138 | pub fn write_header(output: &mut dyn std::io::Write, headers: Header) { [INFO] [stdout] | +++ [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated [INFO] [stdout] --> src/main.rs:565:38 [INFO] [stdout] | [INFO] [stdout] 565 | fn get_output(path: &PathBuf) -> Box { [INFO] [stdout] | ^^^^^^^^^^^^ [INFO] [stdout] | [INFO] [stdout] = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021! [INFO] [stdout] = note: for more information, see [INFO] [stdout] = note: `#[warn(bare_trait_objects)]` on by default [INFO] [stdout] help: use `dyn` [INFO] [stdout] | [INFO] [stdout] 565 | fn get_output(path: &PathBuf) -> Box { [INFO] [stdout] | +++ [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated [INFO] [stdout] --> src/header.rs:138:34 [INFO] [stdout] | [INFO] [stdout] 138 | pub fn write_header(output: &mut std::io::Write, headers: Header) { [INFO] [stdout] | ^^^^^^^^^^^^^^ [INFO] [stdout] | [INFO] [stdout] = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021! [INFO] [stdout] = note: for more information, see [INFO] [stdout] help: use `dyn` [INFO] [stdout] | [INFO] [stdout] 138 | pub fn write_header(output: &mut dyn std::io::Write, headers: Header) { [INFO] [stdout] | +++ [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] error[E0308]: `match` arms have incompatible types [INFO] [stdout] --> src/header.rs:43:1 [INFO] [stdout] | [INFO] [stdout] 43 | / named!(parse_tag_value<&[u8], TagValue>, [INFO] [stdout] 44 | | alt!( [INFO] [stdout] 45 | | do_parse!( [INFO] [stdout] 46 | | tag!(b"\x08\x00\xFF\xFF") >> [INFO] [stdout] ... | [INFO] [stdout] 102 | | ) [INFO] [stdout] 103 | | ); [INFO] [stdout] | | ^ [INFO] [stdout] | | | [INFO] [stdout] | | expected `Result<(&[u8], !), _>`, found `Result<(&[u8], TagValue<'_>), ...>` [INFO] [stdout] | |_this is found to be of type `Result<(&[u8], !), _>` [INFO] [stdout] | `match` arms have incompatible types [INFO] [stdout] | [INFO] [stdout] = note: expected enum `Result<(&_, !), _>` [INFO] [stdout] found enum `Result<(&_, TagValue<'_>), nom::Err<&[u8]>>` [INFO] [stdout] = note: this error originates in the macro `alt` which comes from the expansion of the macro `named` (in Nightly builds, run with -Z macro-backtrace for more info) [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] error[E0308]: `match` arms have incompatible types [INFO] [stdout] --> src/header.rs:43:1 [INFO] [stdout] | [INFO] [stdout] 43 | / named!(parse_tag_value<&[u8], TagValue>, [INFO] [stdout] 44 | | alt!( [INFO] [stdout] 45 | | do_parse!( [INFO] [stdout] 46 | | tag!(b"\x08\x00\xFF\xFF") >> [INFO] [stdout] ... | [INFO] [stdout] 102 | | ) [INFO] [stdout] 103 | | ); [INFO] [stdout] | | ^ [INFO] [stdout] | | | [INFO] [stdout] | | expected `Result<(&[u8], !), _>`, found `Result<(&[u8], TagValue<'_>), ...>` [INFO] [stdout] | |_this is found to be of type `Result<(&[u8], !), _>` [INFO] [stdout] | `match` arms have incompatible types [INFO] [stdout] | [INFO] [stdout] = note: expected enum `Result<(&_, !), _>` [INFO] [stdout] found enum `Result<(&_, TagValue<'_>), nom::Err<&[u8]>>` [INFO] [stdout] = note: this error originates in the macro `alt` which comes from the expansion of the macro `named` (in Nightly builds, run with -Z macro-backtrace for more info) [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] error[E0425]: cannot find function `parallel_asymmetric_cross_correlation` in this scope [INFO] [stdout] --> src/main.rs:751:29 [INFO] [stdout] | [INFO] [stdout] 340 | fn approximate_asymmetric_cross_correlation(bin_count: u64, bin_step: u64, photons: impl Iterator, first_photon: u64) -> (Vec, Vec... [INFO] [stdout] | --------------------------------------------------------------------------------------------------------------------------------------------------------------- similarly named function `approximate_asymmetric_cross_correlation` defined here [INFO] [stdout] ... [INFO] [stdout] 751 | parallel_asymmetric_cross_correlation(&mut bins_forward, &mut bins_backwards, bin_size, photons.clone(), first_photon) [INFO] [stdout] | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: a function with a similar name exists: `approximate_asymmetric_cross_correlation` [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] error[E0425]: cannot find function `parallel_asymmetric_cross_correlation` in this scope [INFO] [stdout] --> src/main.rs:751:29 [INFO] [stdout] | [INFO] [stdout] 340 | fn approximate_asymmetric_cross_correlation(bin_count: u64, bin_step: u64, photons: impl Iterator, first_photon: u64) -> (Vec, Vec... [INFO] [stdout] | --------------------------------------------------------------------------------------------------------------------------------------------------------------- similarly named function `approximate_asymmetric_cross_correlation` defined here [INFO] [stdout] ... [INFO] [stdout] 751 | parallel_asymmetric_cross_correlation(&mut bins_forward, &mut bins_backwards, bin_size, photons.clone(), first_photon) [INFO] [stdout] | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: a function with a similar name exists: `approximate_asymmetric_cross_correlation` [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] error: aborting due to 2 previous errors; 5 warnings emitted [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] Some errors have detailed explanations: E0308, E0425. [INFO] [stdout] [INFO] [stdout] For more information about an error, try `rustc --explain E0308`. [INFO] [stdout] [INFO] [stdout] error: aborting due to 2 previous errors; 5 warnings emitted [INFO] [stdout] [INFO] [stdout] [INFO] [stdout] Some errors have detailed explanations: E0308, E0425. [INFO] [stdout] [INFO] [stdout] For more information about an error, try `rustc --explain E0308`. [INFO] [stdout] [INFO] [stderr] error: could not compile `photon_correlation` (bin "photon_correlation") due to 3 previous errors; 5 warnings emitted [INFO] [stderr] warning: build failed, waiting for other jobs to finish... [INFO] [stderr] error: could not compile `photon_correlation` (bin "photon_correlation" test) due to 3 previous errors; 5 warnings emitted [INFO] running `Command { std: "docker" "inspect" "06ab72bb97a8e14d7f248ce7dd85f4090fea1aff1705ed8b44039cd532f84ba4", kill_on_drop: false }` [INFO] running `Command { std: "docker" "rm" "-f" "06ab72bb97a8e14d7f248ce7dd85f4090fea1aff1705ed8b44039cd532f84ba4", kill_on_drop: false }` [INFO] [stdout] 06ab72bb97a8e14d7f248ce7dd85f4090fea1aff1705ed8b44039cd532f84ba4