ICE with turbofish "no type for node"

[janka102]

Compiler panics when using turbofish and .parse()

I tried this code:

use std::str::FromStr;

struct Six();

impl FromStr for Six {
    type Err = String;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        if s.len() != 6 {
            return Err(format!("Incorrect length {}", s.len()));
        }

        Ok(Six())
    }
}

fn main() {
    let s = String::from("123456");
    let _six: Six = s::<Six>.parse().unwrap();
}

I expected to see this happen: show a warning/error

Instead, this happened: compiler panic'd

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

Backtrace:

error: internal compiler error: src/librustc_typeck/check/mod.rs:2441: no type for node 79: type Six (id=79) in fcx 0x7fe59bbef4a0

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_typeck::check::FnCtxt::node_ty
  15: <rustc_typeck::check::writeback::WritebackCx as rustc::hir::intravisit::Visitor>::visit_ty
  16: rustc::hir::intravisit::walk_path
  17: <rustc_typeck::check::writeback::WritebackCx as rustc::hir::intravisit::Visitor>::visit_expr
  18: rustc::hir::intravisit::walk_expr
  19: <rustc_typeck::check::writeback::WritebackCx as rustc::hir::intravisit::Visitor>::visit_expr
  20: rustc::hir::intravisit::walk_expr
  21: <rustc_typeck::check::writeback::WritebackCx as rustc::hir::intravisit::Visitor>::visit_expr
  22: <rustc_typeck::check::writeback::WritebackCx as rustc::hir::intravisit::Visitor>::visit_local
  23: rustc::hir::intravisit::walk_expr
  24: <rustc_typeck::check::writeback::WritebackCx as rustc::hir::intravisit::Visitor>::visit_expr
  25: rustc_typeck::check::writeback::<impl rustc_typeck::check::FnCtxt>::resolve_type_vars_in_body
  26: rustc::ty::context::GlobalCtxt::enter_local
  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::ty::query::<impl rustc::ty::query::config::QueryAccessors for rustc::ty::query::queries::typeck_item_bodies>::compute
  36: rustc::dep_graph::graph::DepGraph::with_task_impl
  37: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query
  38: rustc::util::common::time
  39: rustc_typeck::check_crate
  40: rustc_interface::passes::analysis
  41: rustc::ty::query::__query_compute::analysis
  42: rustc::ty::query::<impl rustc::ty::query::config::QueryAccessors for rustc::ty::query::queries::analysis>::compute
  43: rustc::dep_graph::graph::DepGraph::with_task_impl
  44: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query
  45: rustc_interface::passes::BoxedGlobalCtxt::access::{{closure}}
  46: rustc_interface::passes::create_global_ctxt::{{closure}}
  47: rustc_interface::interface::run_compiler_in_existing_thread_pool
  48: std::thread::local::LocalKey<T>::with
  49: scoped_tls::ScopedKey<T>::set
  50: syntax::with_globals
query stack during panic:
#0 [typeck_tables_of] processing `main`
#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

[janka102]

Seems similar to #60989, so closing this for now