Closed
Description
Creating a recursive type with infinite size by removing a Box leads to an internal compiler error. Might be the same issue as #57373.
To reproduce this bug, run cargo build on this code:
enum A {
B(C),
}
struct C {
a: Box<A>,
}
fn main() {
}Replace Box<A> by A and run cargo build again:
enum A {
B(C),
}
struct C {
a: A,
}
fn main() {
}I expected to see this happen:
error[E0072]: recursive type `A` has infinite size
--> src/main.rs:1:1
|
1 | enum A {
| ^^^^^^ recursive type has infinite size
2 | B(C),
| - recursive without indirection
|
= help: insert indirection (e.g., a `Box`, `Rc`, or `&`) at some point to make `A` representable
error[E0072]: recursive type `C` has infinite size
--> src/main.rs:5:1
|
5 | struct C {
| ^^^^^^^^ recursive type has infinite size
6 | a: A,
| ---- recursive without indirection
|
= help: insert indirection (e.g., a `Box`, `Rc`, or `&`) at some point to make `C` representable
error: aborting due to 2 previous errors
For more information about this error, try `rustc --explain E0072`.
error: Could not compile `hello_world`.
Instead, this happened:
error: internal compiler error: src/librustc/dep_graph/graph.rs:722: try_mark_previous_green() - Forcing the DepNode should have set its color
thread 'rustc' panicked at 'Box<Any>', src/librustc_errors/lib.rs:635:9
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
stack backtrace:
0: std::sys::unix::backtrace::tracing::imp::unwind_backtrace
at src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:39
1: std::sys_common::backtrace::_print
at src/libstd/sys_common/backtrace.rs:71
2: std::panicking::default_hook::{{closure}}
at src/libstd/sys_common/backtrace.rs:59
at src/libstd/panicking.rs:197
3: std::panicking::default_hook
at src/libstd/panicking.rs:211
4: rustc::util::common::panic_hook
5: std::panicking::rust_panic_with_hook
at src/libstd/panicking.rs:478
6: std::panicking::begin_panic
7: rustc_errors::Handler::bug
8: rustc::util::bug::opt_span_bug_fmt::{{closure}}
9: rustc::ty::context::tls::with_opt::{{closure}}
10: rustc::ty::context::tls::with_context_opt
11: rustc::ty::context::tls::with_opt
12: rustc::util::bug::opt_span_bug_fmt
13: rustc::util::bug::bug_fmt
14: rustc::dep_graph::graph::DepGraph::try_mark_previous_green
15: rustc::dep_graph::graph::DepGraph::try_mark_green
16: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query
17: rustc::ty::AdtDef::sized_constraint_for_ty
18: <core::iter::adapters::flatten::FlatMap<I,U,F> as core::iter::traits::iterator::Iterator>::next
19: <smallvec::SmallVec<A> as core::iter::traits::collect::FromIterator<<A as smallvec::Array>::Item>>::from_iter
20: <T as rustc::ty::context::InternIteratorElement<T,R>>::intern_with
21: rustc::ty::adt_sized_constraint
22: rustc::ty::query::<impl rustc::ty::query::config::QueryAccessors for rustc::ty::query::queries::adt_sized_constraint>::compute
23: rustc::dep_graph::graph::DepGraph::with_task_impl
24: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::force_query
25: rustc::ty::query::plumbing::force_from_dep_node
26: rustc::dep_graph::graph::DepGraph::try_mark_previous_green
27: rustc::dep_graph::graph::DepGraph::try_mark_previous_green
28: rustc::dep_graph::graph::DepGraph::try_mark_previous_green
29: rustc::dep_graph::graph::DepGraph::try_mark_previous_green
30: rustc::dep_graph::graph::DepGraph::try_mark_green
31: rustc::dep_graph::graph::DepGraph::try_mark_green_and_read
32: <rustc_typeck::check::wfcheck::CheckTypeWellFormedVisitor as rustc::hir::itemlikevisit::ParItemLikeVisitor>::visit_item
33: __rust_maybe_catch_panic
at src/libpanic_unwind/lib.rs:87
34: rustc_data_structures::sync::par_for_each_in
35: __rust_maybe_catch_panic
at src/libpanic_unwind/lib.rs:87
36: rustc::hir::Crate::par_visit_all_item_likes
37: rustc::util::common::time
38: rustc_typeck::check_crate
39: rustc_interface::passes::analysis
40: rustc::ty::query::__query_compute::analysis
41: rustc::ty::query::<impl rustc::ty::query::config::QueryAccessors for rustc::ty::query::queries::analysis>::compute
42: rustc::dep_graph::graph::DepGraph::with_task_impl
43: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query
44: rustc_interface::passes::BoxedGlobalCtxt::access::{{closure}}
45: rustc_interface::passes::create_global_ctxt::{{closure}}
46: rustc_interface::interface::run_compiler_in_existing_thread_pool
47: std::thread::local::LocalKey<T>::with
48: scoped_tls::ScopedKey<T>::set
49: syntax::with_globals
query stack during panic:
#0 [adt_sized_constraint] processing `A`
#1 [adt_sized_constraint] processing `C`
#2 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to previous error
note: the compiler unexpectedly panicked. this is a bug.
note: we would appreciate a bug report: https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.md#bug-reports
note: rustc 1.35.0 (3c235d560 2019-05-20) running on x86_64-unknown-linux-gnu
note: compiler flags: -C debuginfo=2 -C incremental --crate-type bin
note: some of the compiler flags provided by cargo are hidden
error: Could not compile `hello_world`.
Meta
rustc --version --verbose:
rustc 1.35.0 (3c235d560 2019-05-20)
binary: rustc
commit-hash: 3c235d5600393dfe6c36eeed34042efad8d4f26e
commit-date: 2019-05-20
host: x86_64-unknown-linux-gnu
release: 1.35.0
LLVM version: 8.0