ICE: explicit failure while typechecking

[Ryman]

matricks ran into this on irc.

Offending code:

fn main() {
    let x = ::std::num::Float::tan(4.0);
    println!("{}", x)
}

Should be:

fn main() {
    let x = 4.0f32.tan();
    println!("{}", x)
}

Expecting an error message about bad usage of static method rather than ICE.

failed to find block with tag 7
error: internal compiler error: unexpected failure
note: the compiler hit an unexpected failure path. this is a bug.
note: we would appreciate a bug report: http://static.rust-lang.org/doc/master/complement-bugreport.html
note: run with `RUST_BACKTRACE=1` for a backtrace
task 'rustc' failed at 'explicit failure', /Users/kevin/Dev/Reference/rust/rust/src/libserialize/ebml.rs:227
stack backtrace:
   1:        0x1045947f4 - rt::backtrace::imp::write::h1b71907322fb2489vAa::v0.11.pre
   2:        0x1044f7066 - rt::unwind::begin_unwind_inner::h5dd8e84e23285c81Zaa::v0.11.pre
   3:        0x10422f668 - rt::unwind::begin_unwind::h0afaae50aaaa8e4eYcl::v0.11.pre
   4:        0x104230680 - ebml::Doc$LT$$x27doc$GT$::as_str_slice::h4d11c05b311f2ab9BDe::v0.11.pre
   5:        0x102079d2f - metadata::decoder::item_type::h243e5551e074f598G69::v0.11.pre
   6:        0x10207c835 - metadata::decoder::get_type::hb5582e616a907f27Wia::v0.11.pre
   7:        0x101947487 - middle::ty::lookup_item_type::h3e307c691087edcezCP::v0.11.pre
   8:        0x101c10bdc - middle::typeck::check::ty_param_bounds_and_ty_for_def::h6471f77949f8f775l4b::v0.11.pre
   9:        0x101bfd462 - middle::typeck::check::check_expr_with_unifier::h3a2740dc12cfdda2sm9::v0.11.pre
  10:        0x101bf72c6 - middle::typeck::check::check_expr_with_unifier::h3a2740dc12cfdda2sm9::v0.11.pre
  11:        0x101c121fb - middle::typeck::check::check_decl_local::h7f69b628e653f2faUAb::v0.11.pre
  12:        0x101c124c3 - middle::typeck::check::check_stmt::hf194f4385cce3706QCb::v0.11.pre
  13:        0x101bd9a9c - middle::typeck::check::check_block_with_expected::ha3e635688ace0786NGb::v0.11.pre
  14:        0x101bd575d - middle::typeck::check::check_fn::h4fb8bd0d54c30ba43p7::v0.11.pre
  15:        0x101bd4f42 - middle::typeck::check::check_bare_fn::h57e5475c845469ceVf7::v0.11.pre
  16:        0x101bd061f - middle::typeck::check::check_item::h557e59440d0ba6bf3x7::v0.11.pre
  17:        0x101bd4dbe - middle::typeck::check::check_item_types::h8c5821585584e9c0vf7::v0.11.pre
  18:        0x101d0cf5f - util::common::time::h595ba6b5ee5d9373V1g::v0.11.pre
  19:        0x101d0bc5b - middle::typeck::check_crate::ha86e8c6e5c22fa75slu::v0.11.pre
  20:        0x102120f36 - driver::driver::phase_3_run_analysis_passes::h50ae3dd75be883aeCNe::v0.11.pre
  21:        0x1021281c7 - driver::driver::compile_input::h9f557912421ed528xcf::v0.11.pre
  22:        0x10214c7bb - run_compiler::h5808939c7770316eELm::v0.11.pre
  23:        0x10216054d - main_args::closure.91893
  24:        0x10215e8d2 - monitor::closure.91771
  25:        0x10215a3fb - task::TaskBuilder::try::closure.91537
  26:        0x1044c15fc - task::spawn_opts::closure.7721
  27:        0x10458f888 - rt::task::Task::run::closure.39970
  28:        0x10459a56c - rust_try
  29:        0x10458f707 - rt::task::Task::run::ha16b6439f988f190x17::v0.11.pre
  30:        0x1044c147f - task::spawn_opts::closure.7693
  31:        0x1045931d6 - rt::thread::thread_start::hfe46724840e25704cG8::v0.11.pre
  32:     0x7fff8fe40899 - _pthread_body
  33:     0x7fff8fe4072a - _pthread_struct_init

rustc 0.11-pre (d1d8497 2014-04-18 11:41:23 -0700)
host: x86_64-apple-darwin

[alexcrichton]

Closing as a dupe of #12919