[INFO] updating cached repository https://github.com/corvuslabs/grammar-fuzzer
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune", kill_on_drop: false }`
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 2e0dd7d51a95ef0e477fdfadcd7c80e5f67e3733
[INFO] testing corvuslabs/grammar-fuzzer against master#8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e for pr-74409
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcorvuslabs%2Fgrammar-fuzzer" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/corvuslabs/grammar-fuzzer on toolchain 8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/corvuslabs/grammar-fuzzer
[INFO] finished tweaking git repo https://github.com/corvuslabs/grammar-fuzzer
[INFO] tweaked toml for git repo https://github.com/corvuslabs/grammar-fuzzer written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/corvuslabs/grammar-fuzzer already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 539498de3ed36d236c7cb7e1ab4a4ac6fe3299efaa56cbbe4651eb11a50037c3
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "539498de3ed36d236c7cb7e1ab4a4ac6fe3299efaa56cbbe4651eb11a50037c3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "539498de3ed36d236c7cb7e1ab4a4ac6fe3299efaa56cbbe4651eb11a50037c3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "539498de3ed36d236c7cb7e1ab4a4ac6fe3299efaa56cbbe4651eb11a50037c3", kill_on_drop: false }`
[INFO] [stdout] 539498de3ed36d236c7cb7e1ab4a4ac6fe3299efaa56cbbe4651eb11a50037c3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "MAP_USER_ID=0" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env@sha256:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] aac9f54a9053135595636948650773bc764f44e163e5b54bf0ac19ac68d7fa95
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "aac9f54a9053135595636948650773bc764f44e163e5b54bf0ac19ac68d7fa95", kill_on_drop: false }`
[INFO] [stderr]    Compiling getrandom v0.1.14
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling nodrop v0.1.14
[INFO] [stderr]    Compiling nom v5.1.1
[INFO] [stderr]    Compiling lexical-core v0.6.7
[INFO] [stderr]    Compiling arrayvec v0.4.12
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling rand_chacha v0.2.2
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling grammar-fuzzer v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/fuzzer.rs:65:17
[INFO] [stdout]    |
[INFO] [stdout] 65 |                 std::mem::replace(node, new_subtree);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 17.36s
[INFO] running `Command { std: "docker" "inspect" "aac9f54a9053135595636948650773bc764f44e163e5b54bf0ac19ac68d7fa95", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "aac9f54a9053135595636948650773bc764f44e163e5b54bf0ac19ac68d7fa95", kill_on_drop: false }`
[INFO] [stdout] aac9f54a9053135595636948650773bc764f44e163e5b54bf0ac19ac68d7fa95
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "MAP_USER_ID=0" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env@sha256:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] fb570fcdaa8ad65b392e53d32c22e65642f89ea0bb326ea11431d6ecfec71934
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "fb570fcdaa8ad65b392e53d32c22e65642f89ea0bb326ea11431d6ecfec71934", kill_on_drop: false }`
[INFO] [stderr]    Compiling grammar-fuzzer v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/fuzzer.rs:65:17
[INFO] [stdout]    |
[INFO] [stdout] 65 |                 std::mem::replace(node, new_subtree);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/fuzzer.rs:65:17
[INFO] [stdout]    |
[INFO] [stdout] 65 |                 std::mem::replace(node, new_subtree);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 3.80s
[INFO] running `Command { std: "docker" "inspect" "fb570fcdaa8ad65b392e53d32c22e65642f89ea0bb326ea11431d6ecfec71934", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fb570fcdaa8ad65b392e53d32c22e65642f89ea0bb326ea11431d6ecfec71934", kill_on_drop: false }`
[INFO] [stdout] fb570fcdaa8ad65b392e53d32c22e65642f89ea0bb326ea11431d6ecfec71934
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "MAP_USER_ID=0" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env@sha256:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 148baaee68c8a7304a150fa2ae4adc20c110a66cabbad25f3f1e06a51078ecab
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "148baaee68c8a7304a150fa2ae4adc20c110a66cabbad25f3f1e06a51078ecab", kill_on_drop: false }`
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]   --> src/fuzzer.rs:65:17
[INFO] [stderr]    |
[INFO] [stderr] 65 |                 std::mem::replace(node, new_subtree);
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]   --> src/fuzzer.rs:65:17
[INFO] [stderr]    |
[INFO] [stderr] 65 |                 std::mem::replace(node, new_subtree);
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.28s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/grammar_fuzzer-1f6673ec34f669ad
[INFO] [stdout] 
[INFO] [stdout] running 24 tests
[INFO] [stdout] test grammar::tests::test_grammar_from_string_map ... ok
[INFO] [stdout] test derivation_tree::tests::test_from_str_for_children ... ok
[INFO] [stdout] test extensions::tests::test_ebnf_to_bnf ... ok
[INFO] [stdout] test grammar::tests::test_find_unavoidable_cycle ... ok
[INFO] [stdout] test shared::tests::test_max_idx ... ok
[INFO] [stdout] test parser::tests::test_tokens ... ok
[INFO] [stdout] test derivation_tree::tests::test_any_possible_expansions ... ok
[INFO] [stdout] test derivation_tree::tests::test_num_possible_expansions ... ok
[INFO] [stdout] test strategy::strategy_cont_tests::test_close_strategy_cont ... ok
[INFO] [stdout] test shared::tests::test_min_idx ... ok
[INFO] [stdout] test shared::tests::test_random_element ... ok
[INFO] [stdout] test strategy::strategy_cont_tests::test_random_strategy_cont ... ok
[INFO] [stdout] test grammar::tests::test_symbol_cost ... ok
[INFO] [stdout] test shared::tests::test_add_to_set ... ok
[INFO] [stdout] test grammar::tests::is_valid_grammar ... ok
[INFO] [stdout] test grammar::tests::test_find_reachable_nonterminals ... ok
[INFO] [stdout] test strategy::strategy_choose_tests::test_random_strategy_choose ... ok
[INFO] [stdout] test parser::tests::test_next_extended_nonterminal ... ok
[INFO] [stdout] test strategy::strategy_cont_tests::test_growth_strategy_cont ... ok
[INFO] [stdout] test derivation_tree::tests::test_display_for_node ... ok
[INFO] [stdout] test parser::tests::test_next_parenthesized_expression ... ok
[INFO] [stdout] test strategy::strategy_choose_tests::test_close_strategy_choose ... ok
[INFO] [stdout] test grammar::tests::expansion_cost ... ok
[INFO] [stdout] test strategy::strategy_choose_tests::test_growth_strategy_choose ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 24 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests grammar-fuzzer
[INFO] [stdout] 
[INFO] [stdout] running 5 tests
[INFO] [stdout] test src/strategy.rs - strategy (line 6) ... ok
[INFO] [stdout] test src/grammar.rs - grammar (line 5) ... ok
[INFO] [stdout] test src/fuzzer.rs - fuzzer (line 5) ... ok
[INFO] [stdout] test src/extensions.rs - extensions (line 5) ... ok
[INFO] [stdout] test src/lib.rs - (line 6) ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 5 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "148baaee68c8a7304a150fa2ae4adc20c110a66cabbad25f3f1e06a51078ecab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "148baaee68c8a7304a150fa2ae4adc20c110a66cabbad25f3f1e06a51078ecab", kill_on_drop: false }`
[INFO] [stdout] 148baaee68c8a7304a150fa2ae4adc20c110a66cabbad25f3f1e06a51078ecab