[INFO] cloning repository https://github.com/giannifer7/azadi
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/giannifer7/azadi" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgiannifer7%2Fazadi", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgiannifer7%2Fazadi'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 3739c9c8b4fbe8e0662148fb75a4f9bc0cefabbf
[INFO] checking giannifer7/azadi against master#19f42cb9bb65555e7d95dab7d17573ae6c5d634c for pr-139087
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fgiannifer7%2Fazadi" "/workspace/builds/worker-7-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/giannifer7/azadi on toolchain 19f42cb9bb65555e7d95dab7d17573ae6c5d634c
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+19f42cb9bb65555e7d95dab7d17573ae6c5d634c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-7-tc1/source/rust-toolchain.toml
[INFO] started tweaking git repo https://github.com/giannifer7/azadi
[INFO] finished tweaking git repo https://github.com/giannifer7/azadi
[INFO] tweaked toml for git repo https://github.com/giannifer7/azadi written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/giannifer7/azadi 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" "+19f42cb9bb65555e7d95dab7d17573ae6c5d634c" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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@sha256:4b26683ee3c49f365255c425c23003cbf4366de097804722c29c5bbbee3624d2" "/opt/rustwide/cargo-home/bin/cargo" "+19f42cb9bb65555e7d95dab7d17573ae6c5d634c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 98f9ffef589d13a83a5e5797f7a795795efaad2d92be48f7a9a32657ce042dc8
[INFO] running `Command { std: "docker" "start" "-a" "98f9ffef589d13a83a5e5797f7a795795efaad2d92be48f7a9a32657ce042dc8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "98f9ffef589d13a83a5e5797f7a795795efaad2d92be48f7a9a32657ce042dc8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "98f9ffef589d13a83a5e5797f7a795795efaad2d92be48f7a9a32657ce042dc8", kill_on_drop: false }`
[INFO] [stdout] 98f9ffef589d13a83a5e5797f7a795795efaad2d92be48f7a9a32657ce042dc8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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@sha256:4b26683ee3c49f365255c425c23003cbf4366de097804722c29c5bbbee3624d2" "/opt/rustwide/cargo-home/bin/cargo" "+19f42cb9bb65555e7d95dab7d17573ae6c5d634c" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8946a10ab65ced15c177f641a13e0dc54a34d249456a975783111d0423104af4
[INFO] running `Command { std: "docker" "start" "-a" "8946a10ab65ced15c177f641a13e0dc54a34d249456a975783111d0423104af4", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.93
[INFO] [stderr]    Compiling unicode-ident v1.0.16
[INFO] [stderr]     Checking memchr v2.7.4
[INFO] [stderr]    Compiling target-lexicon v0.12.16
[INFO] [stderr]    Compiling libc v0.2.169
[INFO] [stderr]     Checking anstyle v1.0.10
[INFO] [stderr]    Compiling serde v1.0.217
[INFO] [stderr]     Checking utf8parse v0.2.2
[INFO] [stderr]    Compiling autocfg v1.4.0
[INFO] [stderr]     Checking anstyle-query v1.1.2
[INFO] [stderr]     Checking regex-syntax v0.8.5
[INFO] [stderr]    Compiling getrandom v0.3.1
[INFO] [stderr]     Checking colorchoice v1.0.3
[INFO] [stderr]    Compiling once_cell v1.20.3
[INFO] [stderr]     Checking is_terminal_polyfill v1.70.1
[INFO] [stderr]    Compiling serde_json v1.0.138
[INFO] [stderr]     Checking anstyle-parse v0.2.6
[INFO] [stderr]    Compiling rustix v0.38.44
[INFO] [stderr]     Checking ryu v1.0.19
[INFO] [stderr]    Compiling heck v0.5.0
[INFO] [stderr]     Checking itoa v1.0.14
[INFO] [stderr]     Checking strsim v0.11.1
[INFO] [stderr]     Checking linux-raw-sys v0.4.15
[INFO] [stderr]     Checking clap_lex v0.7.4
[INFO] [stderr]     Checking bitflags v2.8.0
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]    Compiling thiserror v2.0.11
[INFO] [stderr]     Checking anstream v0.6.18
[INFO] [stderr]     Checking predicates-core v1.0.9
[INFO] [stderr]     Checking fastrand v2.3.0
[INFO] [stderr]    Compiling doc-comment v0.3.3
[INFO] [stderr]     Checking normalize-line-endings v0.3.0
[INFO] [stderr]     Checking lazy_static v1.5.0
[INFO] [stderr]    Compiling escargot v0.5.13
[INFO] [stderr]     Checking difflib v0.4.0
[INFO] [stderr]    Compiling assert_cmd v2.0.16
[INFO] [stderr]    Compiling num-traits v0.2.19
[INFO] [stderr]     Checking termtree v0.5.1
[INFO] [stderr]     Checking yansi v1.0.1
[INFO] [stderr]     Checking log v0.4.25
[INFO] [stderr]     Checking predicates-tree v1.0.12
[INFO] [stderr] error: failed to write `/opt/rustwide/target/debug/build/target-lexicon-09449c0711905456/output`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   No space left on device (os error 28)
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error: couldn't create a temp dir: No space left on device (os error 28) at path "/opt/rustwide/target/debug/deps/rmeta42oVQS"
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `doc-comment` (lib) due to 1 previous error
[INFO] [stdout] error: couldn't create a temp dir: No space left on device (os error 28) at path "/opt/rustwide/target/debug/deps/rmeta2JwwJx"
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `predicates-tree` (lib) due to 1 previous error
[INFO] [stdout] error: couldn't create a temp dir: No space left on device (os error 28) at path "/opt/rustwide/target/debug/deps/rmetar4zgpw"
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: linking with `cc` failed: exit status: 1
[INFO] [stdout]   |
[INFO] [stdout]   = note:  "cc" "-m64" "/tmp/rustcTeMzNm/symbols.o" "<2 object files omitted>" "-Wl,--as-needed" "-Wl,-Bstatic" "<sysroot>/lib/rustlib/x86_64-unknown-linux-gnu/lib/{libstd-*,libpanic_unwind-*,libobject-*,libmemchr-*,libaddr2line-*,libgimli-*,librustc_demangle-*,libstd_detect-*,libhashbrown-*,librustc_std_workspace_alloc-*,libminiz_oxide-*,libadler2-*,libunwind-*,libcfg_if-*,liblibc-*,liballoc-*,librustc_std_workspace_core-*,libcore-*,libcompiler_builtins-*}.rlib" "-Wl,-Bdynamic" "-lgcc_s" "-lutil" "-lrt" "-lpthread" "-lm" "-ldl" "-lc" "-L" "/tmp/rustcTeMzNm/raw-dylibs" "-B<sysroot>/lib/rustlib/x86_64-unknown-linux-gnu/bin/gcc-ld" "-fuse-ld=lld" "-Wl,-znostart-stop-gc" "-Wl,--eh-frame-hdr" "-Wl,-z,noexecstack" "-L" "<sysroot>/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-o" "/opt/rustwide/target/debug/build/escargot-83dffee84185fae5/build_script_build-83dffee84185fae5" "-Wl,--gc-sections" "-pie" "-Wl,-z,relro,-z,now" "-nodefaultlibs"
[INFO] [stdout]   = note: some arguments are omitted. use `--verbose` to show all linker arguments
[INFO] [stdout]   = note: PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
[INFO] [stdout]           LLVM ERROR: IO failure on output stream: No space left on device
[INFO] [stdout]           collect2: error: ld returned 1 exit status
[INFO] [stdout]           
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: linking with `cc` failed: exit status: 1
[INFO] [stdout]   |
[INFO] [stdout]   = note:  "cc" "-m64" "/tmp/rustcbPokOk/symbols.o" "<2 object files omitted>" "-Wl,--as-needed" "-Wl,-Bstatic" "/opt/rustwide/target/debug/deps/{libautocfg-edb41dba5c1eb139.rlib}.rlib" "<sysroot>/lib/rustlib/x86_64-unknown-linux-gnu/lib/{libstd-*,libpanic_unwind-*,libobject-*,libmemchr-*,libaddr2line-*,libgimli-*,librustc_demangle-*,libstd_detect-*,libhashbrown-*,librustc_std_workspace_alloc-*,libminiz_oxide-*,libadler2-*,libunwind-*,libcfg_if-*,liblibc-*,liballoc-*,librustc_std_workspace_core-*,libcore-*,libcompiler_builtins-*}.rlib" "-Wl,-Bdynamic" "-lgcc_s" "-lutil" "-lrt" "-lpthread" "-lm" "-ldl" "-lc" "-L" "/tmp/rustcbPokOk/raw-dylibs" "-B<sysroot>/lib/rustlib/x86_64-unknown-linux-gnu/bin/gcc-ld" "-fuse-ld=lld" "-Wl,-znostart-stop-gc" "-Wl,--eh-frame-hdr" "-Wl,-z,noexecstack" "-L" "<sysroot>/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-o" "/opt/rustwide/target/debug/build/num-traits-ef8ea05865b1362a/build_script_build-ef8ea05865b1362a" "-Wl,--gc-sections" "-pie" "-Wl,-z,relro,-z,now" "-nodefaultlibs"
[INFO] [stdout]   = note: some arguments are omitted. use `--verbose` to show all linker arguments
[INFO] [stdout]   = note: PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
[INFO] [stdout]           Stack dump:
[INFO] [stdout]           0.    Program arguments: /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/bin/rust-lld -flavor gnu -plugin /usr/libexec/gcc/x86_64-linux-gnu/13/liblto_plugin.so -plugin-opt=/usr/libexec/gcc/x86_64-linux-gnu/13/lto-wrapper -plugin-opt=-fresolution=/tmp/cccXwTgc.res --build-id --eh-frame-hdr -m elf_x86_64 --hash-style=gnu --as-needed -dynamic-linker /lib64/ld-linux-x86-64.so.2 -pie -z now -z relro -o /opt/rustwide/target/debug/build/num-traits-ef8ea05865b1362a/build_script_build-ef8ea05865b1362a /usr/lib/gcc/x86_64-linux-gnu/13/../../../x86_64-linux-gnu/Scrt1.o /usr/lib/gcc/x86_64-linux-gnu/13/../../../x86_64-linux-gnu/crti.o /usr/lib/gcc/x86_64-linux-gnu/13/crtbeginS.o -L/tmp/rustcbPokOk/raw-dylibs -L/opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib -L/opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/bin/gcc-ld -L/usr/lib/gcc/x86_64-linux-gnu/13 -L/usr/lib/gcc/x86_64-linux-gnu/13/../../../x86_64-linux-gnu -L/usr/lib/gcc/x86_64-linux-gnu/13/../../../../lib -L/lib/x86_64-linux-gnu -L/lib/../lib -L/usr/lib/x86_64-linux-gnu -L/usr/lib/../lib -L/usr/lib/gcc/x86_64-linux-gnu/13/../../.. /tmp/rustcbPokOk/symbols.o /opt/rustwide/target/debug/build/num-traits-ef8ea05865b1362a/build_script_build-ef8ea05865b1362a.build_script_build.c7f0dcb3b72ffcc7-cgu.0.rcgu.o /opt/rustwide/target/debug/build/num-traits-ef8ea05865b1362a/build_script_build-ef8ea05865b1362a.2680p88vfan9bhn55u3mk0rv5.rcgu.o --as-needed -Bstatic /opt/rustwide/target/debug/deps/libautocfg-edb41dba5c1eb139.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd-08d24c853dfa6028.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/libpanic_unwind-f41c7a65215001bc.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/libobject-324a72f3859cc505.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/libmemchr-3f9a1ae7a3163538.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/libaddr2line-35c70e3ec45a2062.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/libgimli-3826c46535728f14.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_demangle-0deaaa611a802fbc.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/libstd_detect-615d148bb7698766.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/libhashbrown-c32b6701c734dea8.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_alloc-c653ee3eafa91fda.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/libminiz_oxide-16445c71dc0deba8.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/libadler2-b22d51b368d81808.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/libunwind-803cae50cbd4b0d6.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcfg_if-f43d15dea8145b38.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/liblibc-7a21846f18ba2952.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/liballoc-cb45beb470b27c8c.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_std_workspace_core-186a023b8864be69.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore-74a8d2c13eeedc93.rlib /opt/rustwide/rustup-home/toolchains/19f42cb9bb65555e7d95dab7d17573ae6c5d634c/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcompiler_builtins-80fd9cb0269c67c8.rlib -Bdynamic -lgcc_s -lutil -lrt -lpthread -lm -ldl -lc -znostart-stop-gc --eh-frame-hdr -z noexecstack --gc-sections -z relro -z now /usr/lib/gcc/x86_64-linux-gnu/13/crtendS.o /usr/lib/gcc/x86_64-linux-gnu/13/../../../x86_64-linux-gnu/crtn.o
[INFO] [stdout]           LLVM ERROR: IO failure on output stream: No space left on device
[INFO] [stdout]           collect2: error: ld returned 1 exit status
[INFO] [stdout]           
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `linux-raw-sys` (lib) due to 1 previous error
[INFO] [stderr] error: could not compile `num-traits` (build script) due to 1 previous error
[INFO] [stderr] error: could not compile `escargot` (build script) due to 1 previous error
[INFO] [stdout] error: linking with `cc` failed: exit status: 1
[INFO] [stdout]   |
[INFO] [stdout]   = note:  "cc" "-m64" "/tmp/rustcggcVRj/symbols.o" "<2 object files omitted>" "-Wl,--as-needed" "-Wl,-Bstatic" "<sysroot>/lib/rustlib/x86_64-unknown-linux-gnu/lib/{libstd-*,libpanic_unwind-*,libobject-*,libmemchr-*,libaddr2line-*,libgimli-*,librustc_demangle-*,libstd_detect-*,libhashbrown-*,librustc_std_workspace_alloc-*,libminiz_oxide-*,libadler2-*,libunwind-*,libcfg_if-*,liblibc-*,liballoc-*,librustc_std_workspace_core-*,libcore-*,libcompiler_builtins-*}.rlib" "-Wl,-Bdynamic" "-lgcc_s" "-lutil" "-lrt" "-lpthread" "-lm" "-ldl" "-lc" "-L" "/tmp/rustcggcVRj/raw-dylibs" "-B<sysroot>/lib/rustlib/x86_64-unknown-linux-gnu/bin/gcc-ld" "-fuse-ld=lld" "-Wl,-znostart-stop-gc" "-Wl,--eh-frame-hdr" "-Wl,-z,noexecstack" "-L" "<sysroot>/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-o" "/opt/rustwide/target/debug/build/assert_cmd-939664ab97d109af/build_script_build-939664ab97d109af" "-Wl,--gc-sections" "-pie" "-Wl,-z,relro,-z,now" "-nodefaultlibs"
[INFO] [stdout]   = note: some arguments are omitted. use `--verbose` to show all linker arguments
[INFO] [stdout]   = note: collect2: fatal error: ld terminated with signal 7 [Bus error], core dumped
[INFO] [stdout]           compilation terminated.
[INFO] [stdout]           
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `assert_cmd` (build script) due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "8946a10ab65ced15c177f641a13e0dc54a34d249456a975783111d0423104af4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8946a10ab65ced15c177f641a13e0dc54a34d249456a975783111d0423104af4", kill_on_drop: false }`
[INFO] [stdout] 8946a10ab65ced15c177f641a13e0dc54a34d249456a975783111d0423104af4