1.27 Internal compiler error while passing a not-variable-bind generator into a macro:

[DutchGhost]

passing a generator as tmp into a macro caused an ICE:

#![feature(generators, generator_trait)]

use std::ops::{GeneratorState, Generator};

macro_rules! yield_from {
    ($generator:expr) => {
        unsafe {
            loop {
                match $generator.resume() {
                    GeneratorState::Yielded(y) => yield y,
                    GeneratorState::Complete(ret) => break ret,
                }
            }
        }
    };
}


fn main() {
    || {
        yield_from!(|| {
            yield;
        });
        return;
    };
}

Backtrace:

error: internal compiler error: librustc_mir\transform\generator.rs:495: Broken MIR: generator contains type [generator@src\lib.rs:108:25: 110:14 {()}] in MIR, but typeck only knows about for<'r> {&'r mut [generator@src\lib.rs:108:25: 110:14 {()}], std::ops::GeneratorState<(), ()>, ()}
   --> src\lib.rs:107:9
    |
107 | /         || {
108 | |             yield_from!(|| {
109 | |                 yield;
110 | |             });
111 | |             return;
112 | |         };
    | |_________^

thread 'main' panicked at 'Box<Any>', librustc_errors\lib.rs:499:9
stack backtrace:
   0: <std::collections::hash::map::DefaultHasher as core::fmt::Debug>::fmt
   1: <std::sys::windows::dynamic_lib::DynamicLibrary as core::ops::drop::Drop>::drop
   2: std::panicking::take_hook
   3: std::panicking::take_hook
   4: <rustc::ty::SymbolName as core::fmt::Debug>::fmt
   5: std::panicking::rust_panic_with_hook
   6: <rustc_mir::dataflow::graphviz::Edge as core::fmt::Debug>::fmt
   7: <rustc_mir::transform::uniform_array_move_out::LocalUse as core::fmt::Debug>::fmt
   8: <rustc_mir::transform::qualify_consts::Qualif as core::fmt::UpperHex>::fmt
   9: <rustc_mir::transform::qualify_consts::Qualif as core::fmt::UpperHex>::fmt
  10: <rustc_mir::transform::qualify_consts::Qualif as core::fmt::UpperHex>::fmt
  11: <rustc_mir::transform::qualify_consts::Qualif as core::fmt::UpperHex>::fmt
  12: <rustc_mir::dataflow::impls::borrows::Borrows<'a, 'gcx, 'tcx> as rustc_mir::dataflow::BitDenotation>::start_block_effect
  13: <rustc_mir::dataflow::impls::borrows::Borrows<'a, 'gcx, 'tcx> as rustc_mir::dataflow::BitDenotation>::start_block_effect
  14: <rustc_mir::transform::generator::StateTransform as rustc_mir::transform::MirPass>::run_pass
  15: <rustc_mir::transform::MirSource as core::fmt::Debug>::fmt
  16: rustc_mir::transform::optimized_mir
  17: rustc::ty::query::on_disk_cache::__ty_decoder_impl::<impl serialize::serialize::Decoder for rustc::ty::query::on_disk_cache::CacheDecoder<'a, 'tcx, 'x>>::read_str
  18: rustc::ty::context::tls::track_diagnostic
  19: rustc::ty::context::tls::track_diagnostic
  20: rustc::dep_graph::graph::DepGraph::assert_ignored
  21: rustc::ty::context::tls::track_diagnostic
  22: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::try_print_query_stack
  23: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::try_print_query_stack
  24: rustc::ty::query::<impl rustc::ty::context::TyCtxt<'a, 'tcx, 'lcx>>::optimized_mir
  25: rustc_mir::shim::provide
  26: rustc::ty::query::on_disk_cache::__ty_decoder_impl::<impl serialize::serialize::Decoder for rustc::ty::query::on_disk_cache::CacheDecoder<'a, 'tcx, 'x>>::read_str
  27: rustc::ty::context::tls::track_diagnostic
  28: rustc::ty::context::tls::track_diagnostic
  29: rustc::dep_graph::graph::DepGraph::assert_ignored
  30: rustc::ty::context::tls::track_diagnostic
  31: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::try_print_query_stack
  32: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::try_print_query_stack
  33: rustc::ty::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::instance_mir
  34: rustc_mir::monomorphize::collector::collect_crate_mono_items
  35: rustc_mir::monomorphize::collector::collect_crate_mono_items
  36: rustc_mir::util::def_use::Info::use_count
  37: <rustc_mir::dataflow::impls::borrows::Borrows<'a, 'gcx, 'tcx> as rustc_mir::dataflow::BitDenotation>::start_block_effect
  38: rustc_mir::monomorphize::collector::collect_crate_mono_items
  39: <rustc_codegen_llvm::time_graph::TimelineId as core::fmt::Debug>::fmt
  40: <rustc_codegen_llvm::base::ValueIter as core::iter::iterator::Iterator>::next
  41: rustc::ty::context::tls::track_diagnostic
  42: rustc::ty::context::tls::track_diagnostic
  43: rustc::dep_graph::graph::DepGraph::assert_ignored
  44: rustc::ty::context::tls::track_diagnostic
  45: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::try_print_query_stack
  46: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::try_print_query_stack
  47: <rustc_codegen_llvm::back::linker::MsvcLinker<'a> as rustc_codegen_llvm::back::linker::Linker>::finalize
  48: rustc::ty::context::tls::track_diagnostic
  49: rustc::ty::context::tls::track_diagnostic
  50: rustc::dep_graph::graph::DepGraph::assert_ignored
  51: rustc::ty::context::tls::track_diagnostic
  52: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::try_print_query_stack
  53: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::try_print_query_stack
  54: <rustc_metadata::encoder::ImplVisitor<'a, 'tcx> as rustc::hir::itemlikevisit::ItemLikeVisitor<'v>>::visit_item
  55: rustc_metadata::cstore_impl::<impl rustc::middle::cstore::CrateStore for rustc_metadata::cstore::CStore>::encode_metadata
  56: rustc::ty::context::TyCtxt::encode_metadata
  57: rustc_codegen_llvm::base::codegen_instance
  58: <rustc_codegen_llvm::time_graph::TimelineId as core::fmt::Debug>::fmt
  59: <rustc_codegen_llvm::base::ValueIter as core::iter::iterator::Iterator>::next
  60: <rustc_codegen_llvm::LlvmCodegenBackend as rustc_codegen_utils::codegen_backend::CodegenBackend>::codegen_crate
  61: rustc_driver::target_features::add_configuration
  62: rustc_driver::driver::phase_4_codegen
  63: rustc_driver::profile::dump
  64: <humantime::date::Error as std::error::Error>::cause
  65: <rustc_driver::pretty::IdentifiedAnnotation<'hir> as rustc_driver::pretty::PrinterSupport>::sess
  66: <unknown>
  67: rustc_driver::driver::compile_input
  68: rustc_driver::run_compiler
  69: <env_logger::filter::inner::Filter as core::fmt::Display>::fmt
  70: <rustc_driver::derive_registrar::Finder as rustc::hir::itemlikevisit::ItemLikeVisitor<'v>>::visit_item
  71: _rust_maybe_catch_panic
  72: <rustc_driver::derive_registrar::Finder as rustc::hir::itemlikevisit::ItemLikeVisitor<'v>>::visit_item
  73: rustc_driver::main
  74: <unknown>
  75: std::panicking::update_panic_count
  76: _rust_maybe_catch_panic
  77: std::rt::lang_start_internal
  78: <unknown>
  79: <unknown>
  80: BaseThreadInitThunk
  81: RtlUserThreadStart
query stack during panic:
#0 [optimized_mir] processing `internal_compiler_errors::broken_mir::{{closure}}`
#1 [mir_shims] generating MIR shim for `std::ptr::drop_in_place`
#2 [collect_and_partition_mono_items] collect_and_partition_mono_items
#3 [exported_symbols] exported_symbols
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 1.28.0-nightly (e3bf634e0 2018-06-28) running on x86_64-pc-windows-msvc

note: compiler flags: -C debuginfo=2 -C incremental --crate-type lib

note: some of the compiler flags provided by cargo are hidden