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ICE with const generics over a &'static str #67883

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@snf

Description

@snf

This seems to be similar to #60813 and #60814 but with a different stacktrace

#![feature(const_generics)]

struct Caca<const A: &'static str> {
    s: String
}

impl<const A: &str> Default for Caca<A> {
    fn default() -> Self {
        let a = Self::A;
        Self {
            s: A.to_string()
        }
    }
}

fn main() {
    println!("Hello, world!");
}

Stacktrace:

warning: the feature `const_generics` is incomplete and may cause the compiler to crash
 --> 1.rs:1:12
  |
1 | #![feature(const_generics)]
  |            ^^^^^^^^^^^^^^
  |
  = note: `#[warn(incomplete_features)]` on by default

error: internal compiler error: src/librustc/ty/subst.rs:496: Region parameter out of range when substituting in region '_ (root type=Some(&str)) (index=0)

thread 'rustc' panicked at 'Box<Any>', src/librustc_errors/lib.rs:854:9
stack backtrace:
   0: backtrace::backtrace::libunwind::trace
             at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.40/src/backtrace/libunwind.rs:88
   1: backtrace::backtrace::trace_unsynchronized
             at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.40/src/backtrace/mod.rs:66
   2: std::sys_common::backtrace::_print_fmt
             at src/libstd/sys_common/backtrace.rs:77
   3: <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt
             at src/libstd/sys_common/backtrace.rs:59
   4: core::fmt::write
             at src/libcore/fmt/mod.rs:1057
   5: std::io::Write::write_fmt
             at src/libstd/io/mod.rs:1426
   6: std::sys_common::backtrace::_print
             at src/libstd/sys_common/backtrace.rs:62
   7: std::sys_common::backtrace::print
             at src/libstd/sys_common/backtrace.rs:49
   8: std::panicking::default_hook::{{closure}}
             at src/libstd/panicking.rs:195
   9: std::panicking::default_hook
             at src/libstd/panicking.rs:215
  10: rustc_driver::report_ice
  11: std::panicking::rust_panic_with_hook
             at src/libstd/panicking.rs:476
  12: std::panicking::begin_panic
  13: rustc_errors::HandlerInner::span_bug
  14: rustc_errors::Handler::span_bug
  15: rustc::util::bug::opt_span_bug_fmt::{{closure}}
  16: rustc::ty::context::tls::with_opt::{{closure}}
  17: rustc::ty::context::tls::with_opt
  18: rustc::util::bug::opt_span_bug_fmt
  19: rustc::util::bug::span_bug_fmt
  20: <rustc::ty::subst::SubstFolder as rustc::ty::fold::TypeFolder>::fold_region
  21: rustc::ty::structural_impls::<impl rustc::ty::fold::TypeFoldable for &rustc::ty::TyS>::super_fold_with
  22: <rustc::ty::subst::SubstFolder as rustc::ty::fold::TypeFolder>::fold_ty
  23: rustc_typeck::check::FnCtxt::instantiate_value_path
  24: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_kind
  25: rustc_typeck::check::expr::<impl rustc_typeck::check::FnCtxt>::check_expr_with_expectation_and_needs
  26: rustc::ty::context::tls::with_context::{{closure}}
  27: rustc_typeck::check::typeck_tables_of
  28: rustc::ty::query::__query_compute::typeck_tables_of
  29: rustc::ty::query::<impl rustc::ty::query::config::QueryAccessors for rustc::ty::query::queries::typeck_tables_of>::compute
  30: rustc::dep_graph::graph::DepGraph::with_task_impl
  31: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query
  32: rustc::ty::<impl rustc::ty::context::TyCtxt>::par_body_owners
  33: rustc_typeck::check::typeck_item_bodies
  34: rustc::ty::query::__query_compute::typeck_item_bodies
  35: rustc::dep_graph::graph::DepGraph::with_task_impl
  36: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query
  37: rustc_typeck::check_crate
  38: rustc_interface::passes::analysis
  39: rustc::ty::query::__query_compute::analysis
  40: rustc::dep_graph::graph::DepGraph::with_task_impl
  41: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query
  42: rustc::ty::context::tls::enter_global
  43: rustc_interface::interface::run_compiler_in_existing_thread_pool
  44: std::thread::local::LocalKey<T>::with
  45: scoped_tls::ScopedKey<T>::set
  46: syntax::with_globals
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

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 1.42.0-nightly (ed33453a3 2019-12-25) running on x86_64-unknown-linux-gnu

query stack during panic:
#0 [typeck_tables_of] processing `<Caca<A> as std::default::Default>::{{constant}}#0`
#1 [typeck_item_bodies] type-checking all item bodies
#2 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to previous error

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    C-bugCategory: This is a bug.F-const_generics`#![feature(const_generics)]`I-ICEIssue: The compiler panicked, giving an Internal Compilation Error (ICE) ❄️P-mediumMedium priorityT-compilerRelevant to the compiler team, which will review and decide on the PR/issue.glacierICE tracked in rust-lang/glacier.requires-nightlyThis issue requires a nightly compiler in some way.

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