Closed
Description
This is a slightly modified version of the compile-fail/const-size_of-cycle test, adding a field at the end of the struct.
#![feature(const_fn)]
struct Foo {
bytes: [u8; std::mem::size_of::<Foo>()],
x: usize,
}
fn main() {}It ends up in the following ICE. The "unsupported cyclic reference between types/traits detected" error is expected.
error[E0391]: unsupported cyclic reference between types/traits detected
--> src/test/compile-fail/const-size_of-cycle.rs:14:5
|
14 | bytes: [u8; std::mem::size_of::<Foo>()],
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cyclic reference
|
note: the cycle begins when processing `Foo::bytes`...
--> src/test/compile-fail/const-size_of-cycle.rs:14:5
|
14 | bytes: [u8; std::mem::size_of::<Foo>()],
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: ...which then requires const-evaluating `Foo::{{initializer}}`...
--> src/test/compile-fail/const-size_of-cycle.rs:14:17
|
14 | bytes: [u8; std::mem::size_of::<Foo>()],
| ^^^^^^^^^^^^^^^^^^^^^^^^^^
note: ...which then requires computing layout of `Foo`...
= note: ...which then again requires processing `Foo::bytes`, completing the cycle.
error: internal compiler error: src/librustc/ty/layout.rs:1541: Layout::compute: unexpected type `[type 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 1.21.0-nightly (97b01abf3 2017-08-31) running on x86_64-apple-darwin
note: run with `RUST_BACKTRACE=1` for a backtrace
thread 'rustc' panicked at 'Box<Any>', src/librustc_errors/lib.rs:492:8
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
stack backtrace:
0: std::sys::imp::backtrace::tracing::imp::unwind_backtrace
1: std::panicking::default_hook::{{closure}}
2: std::panicking::default_hook
3: std::panicking::rust_panic_with_hook
4: std::panicking::begin_panic
5: rustc_errors::Handler::bug
6: rustc::session::opt_span_bug_fmt::{{closure}}
7: rustc::session::opt_span_bug_fmt
8: rustc::session::bug_fmt
9: rustc::ty::layout::Layout::compute_uncached
10: rustc::ty::util::layout_raw
11: rustc::ty::maps::<impl rustc::ty::maps::queries::layout_raw<'tcx>>::try_get
12: rustc::ty::maps::TyCtxtAt::layout_raw
13: rustc::ty::util::<impl rustc::ty::TyS<'tcx>>::layout
14: <&'a mut I as core::iter::iterator::Iterator>::next
15: rustc::ty::layout::Layout::compute_uncached
16: rustc::ty::util::layout_raw
17: rustc::ty::maps::<impl rustc::ty::maps::queries::layout_raw<'tcx>>::try_get
18: rustc::ty::maps::TyCtxtAt::layout_raw
19: rustc::ty::maps::<impl rustc::ty::context::TyCtxt<'a, 'tcx, 'lcx>>::layout_raw
20: rustc_const_eval::eval::eval_const_expr_partial::{{closure}}
21: rustc_const_eval::eval::eval_const_expr_partial
22: rustc_const_eval::eval::eval_const_expr_partial
23: rustc_const_eval::eval::eval_const_expr_partial
24: rustc_const_eval::eval::eval_const_expr_partial
25: rustc_const_eval::eval::const_eval
26: rustc::ty::maps::<impl rustc::ty::maps::queries::const_eval<'tcx>>::try_get
27: rustc::ty::maps::TyCtxtAt::const_eval
28: rustc::middle::const_val::eval_length
29: <rustc_typeck::astconv::AstConv<'gcx, 'tcx> + 'o>::ast_ty_to_ty
30: rustc_typeck::collect::type_of
31: rustc::dep_graph::graph::DepGraph::with_task
32: rustc::ty::maps::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::cycle_check
33: rustc::ty::maps::<impl rustc::ty::maps::queries::type_of<'tcx>>::try_get
34: rustc::ty::maps::TyCtxtAt::type_of
35: rustc::ty::maps::<impl rustc::ty::context::TyCtxt<'a, 'tcx, 'lcx>>::type_of
36: <rustc_typeck::collect::CollectItemTypesVisitor<'a, 'tcx> as rustc::hir::intravisit::Visitor<'tcx>>::visit_item
37: rustc_typeck::check_crate::{{closure}}::{{closure}}
38: rustc_typeck::check_crate
39: rustc::ty::context::TyCtxt::create_and_enter
40: rustc_driver::driver::compile_input
41: rustc_driver::run_compiler