internal compiler error: 'parse_fn_style: bad fn_style i'

[farcaller]

Freshly built rust 40a9797 fails with:

task 'rustc' failed at 'parse_fn_style: bad fn_style i', /private/tmp/rust-zA4W/src/librustc/metadata/tydecode.rs:449
stack backtrace:
   1:        0x108636104 - rt::backtrace::imp::write::hf67e92fae1af2c3edWa::v0.11.pre
   2:        0x10859aa16 - rt::unwind::begin_unwind_inner::hf3cfd6afc309d855Hwa::v0.11.pre
   3:        0x108599bb7 - rt::unwind::begin_unwind_fmt::hfeb6b864fec66810Rva::v0.11.pre
   4:        0x1064049ba - metadata::tydecode::parse_bare_fn_ty::hb3883d60e5d7aec1Pd6::v0.11.pre
   5:        0x106432b2c - metadata::decoder::get_method::hb6238ea8c6e21ad52fa::v0.11.pre
   6:        0x1064325b6 - metadata::decoder::item_impl_methods::closure.84815
   7:        0x10829d0d9 - ebml::reader::tagged_docs::hfa8f46058ff98eedm0e::v0.11.pre
   8:        0x106433afe - metadata::decoder::get_impl::h799950dfbf263311mea::v0.11.pre
   9:        0x105e8d884 - metadata::csearch::get_impl::hac21fc050fde0f82SZb::v0.11.pre
  10:        0x1060a4b2c - middle::typeck::coherence::CoherenceChecker$LT$$x27a$GT$::add_external_crates::closure.70418
  11:        0x10643d545 - metadata::decoder::each_impl::closure.84946
  12:        0x10829d0d9 - ebml::reader::tagged_docs::hfa8f46058ff98eedm0e::v0.11.pre
  13:        0x10643d468 - metadata::decoder::each_impl::h608d792928a286b7wRa::v0.11.pre
  14:        0x1060a4a29 - metadata::csearch::each_impl::h3333044e30e6c489gcc::v0.11.pre
  15:        0x1060a4981 - middle::typeck::coherence::CoherenceChecker$LT$$x27a$GT$::add_external_crates::closure.70416
  16:        0x1060a479a - metadata::cstore::CStore::iter_crate_data::he6a5c06c65408a7dAJb::v0.11.pre
  17:        0x1060a55d5 - middle::typeck::coherence::check_coherence::h30027d017ddcb6801Pr::v0.11.pre
  18:        0x1060b88bf - util::common::time::h2ab3eca2ad6c60e8Rwg::v0.11.pre
  19:        0x1060b7563 - middle::typeck::check_crate::h6dd6983fd6a13352bZt::v0.11.pre
  20:        0x1064d1beb - driver::driver::phase_3_run_analysis_passes::h6ccb67e2e6290f21pje::v0.11.pre
  21:        0x1064d80e1 - driver::driver::compile_input::h59c81631fd9537e8mIe::v0.11.pre
  22:        0x1064fd316 - run_compiler::h0dc49fffbed91a19tgm::v0.11.pre
  23:        0x106510fad - main_args::closure.91897
  24:        0x10650f7c2 - monitor::closure.91782
  25:        0x10650b2eb - task::TaskBuilder::try::closure.91548
  26:        0x105cac82c - task::spawn_opts::closure.7934
  27:        0x108631188 - rt::task::Task::run::closure.40060
  28:        0x10863bd3c - rust_try
  29:        0x108631007 - rt::task::Task::run::hf8ddbb38ce7f1661An8::v0.11.pre
  30:        0x105cac6af - task::spawn_opts::closure.7906
  31:        0x108634ae6 - rt::thread::thread_start::haf14161365de64afl28::v0.11.pre
  32:     0x7fff8b82b899 - _pthread_body
  33:     0x7fff8b82b72a - _pthread_struct_init

[farcaller]

Never mind, cleaning up build cruft fixed this.