compile_error! causes an ICE

[whitequark]

To reproduce, clone smoltcp-rs/smoltcp@cedf66a7, uncomment the code block labeled "XXX compiler bug" in src/lib.rs, and then:

$ RUST_BACKTRACE=1 cargo test --example tcpdump
   Compiling smoltcp v0.4.0 (file:///home/whitequark/Projects/smoltcp)

(some errors omitted...)

error: internal compiler error: /checkout/src/librustc_typeck/check/mod.rs:2015: no type for node 46: type u8 (id=46) in fcx 0x7f8c5bff1fb0

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 1.22.0-nightly (1ed7d41d8 2017-09-24) running on x86_64-unknown-linux-gnu

note: run with `RUST_BACKTRACE=1` for a backtrace

thread 'rustc' panicked at 'Box<Any>', /checkout/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
             at /checkout/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:49
   1: std::sys_common::backtrace::_print
             at /checkout/src/libstd/sys_common/backtrace.rs:71
   2: std::panicking::default_hook::{{closure}}
             at /checkout/src/libstd/sys_common/backtrace.rs:60
             at /checkout/src/libstd/panicking.rs:381
   3: std::panicking::default_hook
             at /checkout/src/libstd/panicking.rs:391
   4: std::panicking::rust_panic_with_hook
             at /checkout/src/libstd/panicking.rs:577
   5: std::panicking::begin_panic
   6: rustc_errors::Handler::bug
   7: rustc::session::opt_span_bug_fmt::{{closure}}
   8: rustc::session::opt_span_bug_fmt
   9: rustc::session::bug_fmt
  10: rustc_typeck::check::FnCtxt::node_ty
  11: <rustc_typeck::check::writeback::WritebackCx<'cx, 'gcx, 'tcx> as rustc::hir::intravisit::Visitor<'gcx>>::visit_ty
  12: <rustc_typeck::check::writeback::WritebackCx<'cx, 'gcx, 'tcx> as rustc::hir::intravisit::Visitor<'gcx>>::visit_ty
  13: <rustc_typeck::check::writeback::WritebackCx<'cx, 'gcx, 'tcx> as rustc::hir::intravisit::Visitor<'gcx>>::visit_ty
  14: rustc::hir::intravisit::walk_path_parameters
  15: <rustc_typeck::check::writeback::WritebackCx<'cx, 'gcx, 'tcx> as rustc::hir::intravisit::Visitor<'gcx>>::visit_ty
  16: rustc::hir::intravisit::walk_path_parameters
  17: <rustc_typeck::check::writeback::WritebackCx<'cx, 'gcx, 'tcx> as rustc::hir::intravisit::Visitor<'gcx>>::visit_expr
  18: <rustc_typeck::check::writeback::WritebackCx<'cx, 'gcx, 'tcx> as rustc::hir::intravisit::Visitor<'gcx>>::visit_expr
  19: <rustc_typeck::check::writeback::WritebackCx<'cx, 'gcx, 'tcx> as rustc::hir::intravisit::Visitor<'gcx>>::visit_expr
  20: <rustc_typeck::check::writeback::WritebackCx<'cx, 'gcx, 'tcx> as rustc::hir::intravisit::Visitor<'gcx>>::visit_expr
  21: <rustc_typeck::check::writeback::WritebackCx<'cx, 'gcx, 'tcx> as rustc::hir::intravisit::Visitor<'gcx>>::visit_expr
  22: <rustc_typeck::check::writeback::WritebackCx<'cx, 'gcx, 'tcx> as rustc::hir::intravisit::Visitor<'gcx>>::visit_expr
  23: <rustc_typeck::check::writeback::WritebackCx<'cx, 'gcx, 'tcx> as rustc::hir::intravisit::Visitor<'gcx>>::visit_expr
  24: <rustc_typeck::check::writeback::WritebackCx<'cx, 'gcx, 'tcx> as rustc::hir::intravisit::Visitor<'gcx>>::visit_expr
  25: <rustc_typeck::check::writeback::WritebackCx<'cx, 'gcx, 'tcx> as rustc::hir::intravisit::Visitor<'gcx>>::visit_expr
  26: <rustc_typeck::check::writeback::WritebackCx<'cx, 'gcx, 'tcx> as rustc::hir::intravisit::Visitor<'gcx>>::visit_expr
  27: rustc_typeck::check::typeck_tables_of::{{closure}}
  28: rustc_typeck::check::typeck_tables_of
  29: rustc::dep_graph::graph::DepGraph::with_task
  30: rustc::ty::maps::<impl rustc::ty::maps::queries::typeck_tables_of<'tcx>>::try_get
  31: rustc::ty::maps::TyCtxtAt::typeck_tables_of
  32: rustc::ty::maps::<impl rustc::ty::context::TyCtxt<'a, 'tcx, 'lcx>>::typeck_tables_of
  33: rustc_typeck::check::typeck_item_bodies
  34: rustc::dep_graph::graph::DepGraph::with_task
  35: rustc::ty::maps::<impl rustc::ty::maps::queries::typeck_item_bodies<'tcx>>::try_get
  36: rustc::ty::maps::TyCtxtAt::typeck_item_bodies
  37: rustc::ty::maps::<impl rustc::ty::context::TyCtxt<'a, 'tcx, 'lcx>>::typeck_item_bodies
  38: rustc_typeck::check_crate
  39: rustc::ty::context::TyCtxt::create_and_enter
  40: rustc_driver::driver::compile_input
  41: rustc_driver::run_compiler

error: Could not compile `smoltcp`.

[petrochenkov]

Should be fixed in #44945