[INFO] cloning repository https://github.com/mayshukla/butterfly-prolog
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/mayshukla/butterfly-prolog" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmayshukla%2Fbutterfly-prolog", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmayshukla%2Fbutterfly-prolog'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] d2a8ae348ff76e157064b333c87d16e5e2d2bf36
[INFO] building mayshukla/butterfly-prolog against master#ad211ced81509462cdfe4c29ed10f97279a0acae for pr-135216
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmayshukla%2Fbutterfly-prolog" "/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/mayshukla/butterfly-prolog on toolchain ad211ced81509462cdfe4c29ed10f97279a0acae
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/mayshukla/butterfly-prolog
[INFO] finished tweaking git repo https://github.com/mayshukla/butterfly-prolog
[INFO] tweaked toml for git repo https://github.com/mayshukla/butterfly-prolog written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/mayshukla/butterfly-prolog 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" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0629123a691dfe1b9d0595543a64ed1ce8717801228d183f67fafb02fde5563b
[INFO] running `Command { std: "docker" "start" "-a" "0629123a691dfe1b9d0595543a64ed1ce8717801228d183f67fafb02fde5563b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0629123a691dfe1b9d0595543a64ed1ce8717801228d183f67fafb02fde5563b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0629123a691dfe1b9d0595543a64ed1ce8717801228d183f67fafb02fde5563b", kill_on_drop: false }`
[INFO] [stdout] 0629123a691dfe1b9d0595543a64ed1ce8717801228d183f67fafb02fde5563b
[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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5e35b7bee9d70e62549bc7cb757d2cec234571433dddd4fba3fde6c931db1de2
[INFO] running `Command { std: "docker" "start" "-a" "5e35b7bee9d70e62549bc7cb757d2cec234571433dddd4fba3fde6c931db1de2", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.37
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling ucd-trie v0.1.3
[INFO] [stderr]    Compiling syn v1.0.91
[INFO] [stderr]    Compiling maplit v1.0.2
[INFO] [stderr]    Compiling pest v2.1.3
[INFO] [stderr]    Compiling quote v1.0.18
[INFO] [stderr]    Compiling pest_meta v2.1.3
[INFO] [stderr]    Compiling pest_generator v2.1.3
[INFO] [stderr]    Compiling pest_derive v2.1.0
[INFO] [stderr]    Compiling butterfly-prolog v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::cell::RefCell`
[INFO] [stdout]  --> src/compiler.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::cell::RefCell;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::cell::RefMut`
[INFO] [stdout]  --> src/compiler.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::cell::RefMut;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable expression
[INFO] [stdout]    --> src/compiler.rs:377:9
[INFO] [stdout]     |
[INFO] [stdout] 375 |         todo!();
[INFO] [stdout]     |         ------- any code following this expression is unreachable
[INFO] [stdout] 376 |
[INFO] [stdout] 377 |         None
[INFO] [stdout]     |         ^^^^ unreachable expression
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unreachable_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `trail_top`
[INFO] [stdout]    --> src/compiler.rs:367:13
[INFO] [stdout]     |
[INFO] [stdout] 367 |         let trail_top = self.trail.len();
[INFO] [stdout]     |             ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_trail_top`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `base`
[INFO] [stdout]    --> src/compiler.rs:369:13
[INFO] [stdout]     |
[INFO] [stdout] 369 |         let base = heap_top;
[INFO] [stdout]     |             ^^^^ help: if this is intentional, prefix it with an underscore: `_base`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new`, `push_clause`, and `push_query` are never used
[INFO] [stdout]   --> src/ast.rs:8:12
[INFO] [stdout]    |
[INFO] [stdout] 7  | impl Program {
[INFO] [stdout]    | ------------ associated items in this implementation
[INFO] [stdout] 8  |     pub fn new() -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] ...
[INFO] [stdout] 12 |     pub fn push_clause(&mut self, clause: Clause) {
[INFO] [stdout]    |            ^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 16 |     pub fn push_query(&mut self, query: Query) {
[INFO] [stdout]    |            ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Compound` and `Simple` are never constructed
[INFO] [stdout]   --> src/ast.rs:29:5
[INFO] [stdout]    |
[INFO] [stdout] 28 | pub enum Term {
[INFO] [stdout]    |          ---- variants in this enum
[INFO] [stdout] 29 |     Compound(CompoundTerm),
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout] 30 |     Simple(SimpleTerm),
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Term` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Atom` and `Variable` are never constructed
[INFO] [stdout]   --> src/ast.rs:41:5
[INFO] [stdout]    |
[INFO] [stdout] 40 | pub enum SimpleTerm {
[INFO] [stdout]    |          ---------- variants in this enum
[INFO] [stdout] 41 |     Atom(String),
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 42 |     Variable(String),
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `SimpleTerm` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `ButterflyPLParser` is never constructed
[INFO] [stdout]  --> src/parser.rs:8:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | struct ButterflyPLParser;
[INFO] [stdout]   |        ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `parse` is never used
[INFO] [stdout]   --> src/parser.rs:13:8
[INFO] [stdout]    |
[INFO] [stdout] 13 | pub fn parse(code: &str) -> Result<Program, &str> {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `construct_clause` is never used
[INFO] [stdout]   --> src/parser.rs:37:4
[INFO] [stdout]    |
[INFO] [stdout] 37 | fn construct_clause(pair: Pair<Rule>) -> Clause {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `construct_term` is never used
[INFO] [stdout]   --> src/parser.rs:54:4
[INFO] [stdout]    |
[INFO] [stdout] 54 | fn construct_term(pair: Pair<Rule>) -> Term {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `construct_compound_term` is never used
[INFO] [stdout]   --> src/parser.rs:64:4
[INFO] [stdout]    |
[INFO] [stdout] 64 | fn construct_compound_term(pair: Pair<Rule>) -> Term {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `construct_query` is never used
[INFO] [stdout]   --> src/parser.rs:80:4
[INFO] [stdout]    |
[INFO] [stdout] 80 | fn construct_query(pair: Pair<Rule>) -> Query {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: multiple variants are never constructed
[INFO] [stdout]   --> src/heap.rs:21:5
[INFO] [stdout]    |
[INFO] [stdout] 19 | pub enum HeapTag {
[INFO] [stdout]    |          ------- variants in this enum
[INFO] [stdout] 20 |     // First occurence of variable in a clause
[INFO] [stdout] 21 |     Variable,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 24 |     Unify,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 27 |     Reference,
[INFO] [stdout]    |     ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 30 |     Constant,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 33 |     Number,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 36 |     Arity,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 39 |     Uninitialized,
[INFO] [stdout]    |     ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `HeapTag` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new`, `alloc`, `write`, `read`, and `len` are never used
[INFO] [stdout]   --> src/heap.rs:45:12
[INFO] [stdout]    |
[INFO] [stdout] 44 | impl Heap {
[INFO] [stdout]    | --------- associated items in this implementation
[INFO] [stdout] 45 |     pub fn new() -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] ...
[INFO] [stdout] 53 |     pub fn alloc(&mut self, size: HeapIndex) -> HeapIndex{
[INFO] [stdout]    |            ^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 59 |     pub fn write(&mut self, index: HeapIndex, entry: HeapEntry) {
[INFO] [stdout]    |            ^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 63 |     pub fn read(&self, index: HeapIndex) -> HeapEntry {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 67 |     pub fn len(&self) -> HeapIndex {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `empty`, `new`, and `is_var_or_unify` are never used
[INFO] [stdout]   --> src/heap.rs:73:8
[INFO] [stdout]    |
[INFO] [stdout] 72 | impl HeapEntry {
[INFO] [stdout]    | -------------- associated items in this implementation
[INFO] [stdout] 73 |     fn empty() -> Self {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 77 |     pub fn new(tag: HeapTag, data: HeapIndex) -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] ...
[INFO] [stdout] 81 |     pub fn is_var_or_unify(&self) -> bool {
[INFO] [stdout]    |            ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Compiler` is never constructed
[INFO] [stdout]  --> src/compiler.rs:8:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | struct Compiler {
[INFO] [stdout]   |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `ClauseDescriptor` is never constructed
[INFO] [stdout]   --> src/compiler.rs:27:8
[INFO] [stdout]    |
[INFO] [stdout] 27 | struct ClauseDescriptor {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `QueryDescriptor` is never constructed
[INFO] [stdout]   --> src/compiler.rs:46:8
[INFO] [stdout]    |
[INFO] [stdout] 46 | struct QueryDescriptor {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Spine` is never constructed
[INFO] [stdout]   --> src/compiler.rs:61:8
[INFO] [stdout]    |
[INFO] [stdout] 61 | struct Spine {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `SymbolTable` is never constructed
[INFO] [stdout]   --> src/compiler.rs:80:8
[INFO] [stdout]    |
[INFO] [stdout] 80 | struct SymbolTable {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: multiple associated items are never used
[INFO] [stdout]    --> src/compiler.rs:87:12
[INFO] [stdout]     |
[INFO] [stdout] 86  | impl Compiler {
[INFO] [stdout]     | ------------- associated items in this implementation
[INFO] [stdout] 87  |     pub fn new() -> Self {
[INFO] [stdout]     |            ^^^
[INFO] [stdout] ...
[INFO] [stdout] 99  |     pub fn compile(&mut self, program: Program) {
[INFO] [stdout]     |            ^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 110 |     fn compile_clause(&mut self, clause: Clause) {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 156 |     fn create_arity_entry_for_simple_term(&mut self) {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 165 |     fn compile_term(&mut self, term: Term) -> HeapIndex {
[INFO] [stdout]     |        ^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 172 |     fn compile_simple_term(&mut self, term: SimpleTerm) -> HeapIndex {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 182 |     fn compile_simple_term_no_alloc(&mut self, term: SimpleTerm, index: HeapIndex) {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 213 |     fn compile_compound_term(&mut self, term: CompoundTerm) -> HeapIndex {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 246 |     fn compile_query(&mut self, query: Query) {
[INFO] [stdout]     |        ^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 268 |     fn get_subterms(&self, reference: HeapEntry) -> Vec<HeapEntry> {
[INFO] [stdout]     |        ^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 286 |     fn entry_to_register(&self, entry: HeapEntry) -> HeapEntry {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 298 |     fn deref_once(&self, pointer: HeapEntry) -> HeapEntry {
[INFO] [stdout]     |        ^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 306 |     fn deref(&self, pointer: HeapEntry) -> HeapEntry {
[INFO] [stdout]     |        ^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 319 |     fn create_initial_spine(&mut self, queries: Vec<QueryDescriptor>) {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 340 |     fn yield_answer_spine(&mut self) -> Option<Spine> {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 366 |     fn unfold(&self, spine: &mut Spine) -> Option<Spine> {
[INFO] [stdout]     |        ^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 383 |     fn populate_spine_dereferenced_elements(&self, spine: &mut Spine, goal: HeapEntry) {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new`, `push`, `get`, and `get_index` are never used
[INFO] [stdout]    --> src/compiler.rs:401:8
[INFO] [stdout]     |
[INFO] [stdout] 400 | impl SymbolTable {
[INFO] [stdout]     | ---------------- associated items in this implementation
[INFO] [stdout] 401 |     fn new() -> Self {
[INFO] [stdout]     |        ^^^
[INFO] [stdout] ...
[INFO] [stdout] 405 |     fn push(&mut self, symbol: &str) -> usize {
[INFO] [stdout]     |        ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 412 |     fn get(&self, index: usize) -> &str {
[INFO] [stdout]     |        ^^^
[INFO] [stdout] ...
[INFO] [stdout] 416 |     fn get_index(&self, symbol: &str) -> Option<usize> {
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new`, `has_clauses`, and `has_goals` are never used
[INFO] [stdout]    --> src/compiler.rs:426:8
[INFO] [stdout]     |
[INFO] [stdout] 425 | impl Spine {
[INFO] [stdout]     | ---------- associated items in this implementation
[INFO] [stdout] 426 |     fn new(
[INFO] [stdout]     |        ^^^
[INFO] [stdout] ...
[INFO] [stdout] 446 |     fn has_clauses(&self) -> bool {
[INFO] [stdout]     |        ^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 453 |     fn has_goals(&self) -> bool {
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 6.32s
[INFO] running `Command { std: "docker" "inspect" "5e35b7bee9d70e62549bc7cb757d2cec234571433dddd4fba3fde6c931db1de2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5e35b7bee9d70e62549bc7cb757d2cec234571433dddd4fba3fde6c931db1de2", kill_on_drop: false }`
[INFO] [stdout] 5e35b7bee9d70e62549bc7cb757d2cec234571433dddd4fba3fde6c931db1de2
[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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+ad211ced81509462cdfe4c29ed10f97279a0acae" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9aff13e171dbb6196c78d177a6d8008c6f9a0259490d4f235af4e052dfc17811
[INFO] running `Command { std: "docker" "start" "-a" "9aff13e171dbb6196c78d177a6d8008c6f9a0259490d4f235af4e052dfc17811", kill_on_drop: false }`
[INFO] [stderr]    Compiling butterfly-prolog v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::cell::RefCell`
[INFO] [stdout]  --> src/compiler.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::cell::RefCell;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::cell::RefMut`
[INFO] [stdout]  --> src/compiler.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::cell::RefMut;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable expression
[INFO] [stdout]    --> src/compiler.rs:377:9
[INFO] [stdout]     |
[INFO] [stdout] 375 |         todo!();
[INFO] [stdout]     |         ------- any code following this expression is unreachable
[INFO] [stdout] 376 |
[INFO] [stdout] 377 |         None
[INFO] [stdout]     |         ^^^^ unreachable expression
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unreachable_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `trail_top`
[INFO] [stdout]    --> src/compiler.rs:367:13
[INFO] [stdout]     |
[INFO] [stdout] 367 |         let trail_top = self.trail.len();
[INFO] [stdout]     |             ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_trail_top`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `base`
[INFO] [stdout]    --> src/compiler.rs:369:13
[INFO] [stdout]     |
[INFO] [stdout] 369 |         let base = heap_top;
[INFO] [stdout]     |             ^^^^ help: if this is intentional, prefix it with an underscore: `_base`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `Number` is never constructed
[INFO] [stdout]   --> src/heap.rs:33:5
[INFO] [stdout]    |
[INFO] [stdout] 19 | pub enum HeapTag {
[INFO] [stdout]    |          ------- variant in this enum
[INFO] [stdout] ...
[INFO] [stdout] 33 |     Number,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `HeapTag` has derived impls for the traits `Debug` and `Clone`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `yield_answer_spine`, `unfold`, and `populate_spine_dereferenced_elements` are never used
[INFO] [stdout]    --> src/compiler.rs:340:8
[INFO] [stdout]     |
[INFO] [stdout] 86  | impl Compiler {
[INFO] [stdout]     | ------------- methods in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 340 |     fn yield_answer_spine(&mut self) -> Option<Spine> {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 366 |     fn unfold(&self, spine: &mut Spine) -> Option<Spine> {
[INFO] [stdout]     |        ^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 383 |     fn populate_spine_dereferenced_elements(&self, spine: &mut Spine, goal: HeapEntry) {
[INFO] [stdout]     |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `has_clauses` and `has_goals` are never used
[INFO] [stdout]    --> src/compiler.rs:446:8
[INFO] [stdout]     |
[INFO] [stdout] 425 | impl Spine {
[INFO] [stdout]     | ---------- methods in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 446 |     fn has_clauses(&self) -> bool {
[INFO] [stdout]     |        ^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 453 |     fn has_goals(&self) -> bool {
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] rustc-LLVM ERROR: IO failure on output stream: No space left on device
[INFO] [stderr] error: could not compile `butterfly-prolog` (bin "butterfly-prolog" test); 8 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `/opt/rustwide/rustup-home/toolchains/ad211ced81509462cdfe4c29ed10f97279a0acae/bin/rustc --crate-name butterfly_prolog --edition=2021 src/main.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --emit=dep-info,link -C embed-bitcode=no -C debuginfo=2 --test --check-cfg 'cfg(docsrs,test)' --check-cfg 'cfg(feature, values())' -C metadata=80487dbb06b22e83 -C extra-filename=-a18eccc72c197406 --out-dir /opt/rustwide/target/debug/deps -L dependency=/opt/rustwide/target/debug/deps --extern pest=/opt/rustwide/target/debug/deps/libpest-a0db8bb73f1096ce.rlib --extern pest_derive=/opt/rustwide/target/debug/deps/libpest_derive-577907d699b45074.so --cap-lints=forbid` (exit status: 101)
[INFO] running `Command { std: "docker" "inspect" "9aff13e171dbb6196c78d177a6d8008c6f9a0259490d4f235af4e052dfc17811", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9aff13e171dbb6196c78d177a6d8008c6f9a0259490d4f235af4e052dfc17811", kill_on_drop: false }`
[INFO] [stdout] 9aff13e171dbb6196c78d177a6d8008c6f9a0259490d4f235af4e052dfc17811