error building docs for typenum with nightly

[arturoc]

error: internal compiler error: librustc/traits/structural_impls.rs:178: impossible case reached                                      
                                                                                                                                      
thread '<unnamed>' panicked at 'Box<Any>', librustc_errors/lib.rs:599:9                                                               
stack backtrace:                                                                                                                      
   0: std::sys::unix::backtrace::tracing::imp::unwind_backtrace                                                                       
             at libstd/sys/unix/backtrace/tracing/gcc_s.rs:49                                                                         
   1: std::sys_common::backtrace::print                                                                                               
             at libstd/sys_common/backtrace.rs:71                                                                                     
             at libstd/sys_common/backtrace.rs:59                                                                                     
   2: std::panicking::default_hook::{{closure}}                                                                                       
             at libstd/panicking.rs:211                                                                                               
   3: std::panicking::default_hook                                                                                                    
             at libstd/panicking.rs:227                                                                                               
   4: std::panicking::rust_panic_with_hook                                                                                            
             at libstd/panicking.rs:477                                                                                               
   5: std::panicking::begin_panic                                                                                                     
   6: rustc_errors::Handler::bug                                                                                                      
   7: rustc::util::bug::opt_span_bug_fmt::{{closure}}                                                                                 
   8: rustc::ty::context::tls::with_opt::{{closure}}                                                                                  
   9: rustc::ty::context::tls::with_context_opt                                                                                       
  10: rustc::ty::context::tls::with_opt                                                                                               
  11: rustc::util::bug::opt_span_bug_fmt                                                                                              
  12: rustc::util::bug::bug_fmt                                                                                                       
  13: rustc::traits::structural_impls::<impl rustc::ty::context::Lift<'tcx> for rustc::traits::SelectionError<'a>>::lift_to_tcx       
  14: rustc::ty::context::TyCtxt::lift_to_global                                                                                      
  15: rustc::traits::select::SelectionContext::candidate_from_obligation                                                              
  16: rustc::traits::select::SelectionContext::evaluate_stack                                                                         
  17: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  18: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                         
  19: rustc::infer::InferCtxt::probe                                                                                                  
  20: <&'a mut I as core::iter::iterator::Iterator>::next                                                                             
  21: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                 
  22: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                     
  23: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  24: rustc::traits::select::SelectionContext::candidate_from_obligation                                                              
  25: rustc::traits::select::SelectionContext::evaluate_stack                                                                         
  26: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  27: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                         
  28: rustc::infer::InferCtxt::probe                                                                                                  
  29: <&'a mut I as core::iter::iterator::Iterator>::next                                                                             
  30: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                 
  31: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                     
  32: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  33: rustc::traits::select::SelectionContext::candidate_from_obligation                                                              
  34: rustc::traits::select::SelectionContext::evaluate_stack                                                                         
  35: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  36: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                         
  37: rustc::infer::InferCtxt::probe                                                                                                  
  38: <&'a mut I as core::iter::iterator::Iterator>::next                                                                             
  39: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                 
  40: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                     
  41: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  42: rustc::traits::select::SelectionContext::candidate_from_obligation                                                              
  43: rustc::traits::select::SelectionContext::evaluate_stack                                                                         
  44: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  45: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                         
  46: rustc::infer::InferCtxt::probe                                                                                                  
  47: <&'a mut I as core::iter::iterator::Iterator>::next                                                                             
  48: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                 
  49: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                     
  50: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  51: rustc::traits::select::SelectionContext::candidate_from_obligation                                                              
  52: rustc::traits::select::SelectionContext::evaluate_stack                                                                         
  53: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  54: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                         
  55: rustc::infer::InferCtxt::probe                                                                                                  
  56: <&'a mut I as core::iter::iterator::Iterator>::next                                                                             
  57: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                 
  58: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                     
  59: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  60: rustc::traits::select::SelectionContext::candidate_from_obligation                                                              
  61: rustc::traits::select::SelectionContext::evaluate_stack                                                                         
  62: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  63: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                         
  64: rustc::infer::InferCtxt::probe                                                                                                  
  65: <&'a mut I as core::iter::iterator::Iterator>::next                                                                             
  66: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                 
  67: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                     
  68: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  69: rustc::traits::select::SelectionContext::candidate_from_obligation                                                              
  70: rustc::traits::select::SelectionContext::evaluate_stack                                                                         
  71: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  72: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                         
  73: rustc::infer::InferCtxt::probe                                                                                                  
  74: <&'a mut I as core::iter::iterator::Iterator>::next                                                                             
  75: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                 
  76: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                     
  77: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  78: rustc::traits::select::SelectionContext::candidate_from_obligation                                                              
  79: rustc::traits::select::SelectionContext::evaluate_stack                                                                         
  80: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  81: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                         
  82: rustc::infer::InferCtxt::probe                                                                                                  
  83: <&'a mut I as core::iter::iterator::Iterator>::next                                                                             
  84: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                 
  85: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                     
  86: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  87: rustc::traits::select::SelectionContext::candidate_from_obligation                                                              
  88: rustc::traits::select::SelectionContext::evaluate_stack                                                                         
  89: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  90: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                         
  91: rustc::infer::InferCtxt::probe                                                                                                  
  92: <&'a mut I as core::iter::iterator::Iterator>::next                                                                             
  93: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                 
  94: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                     
  95: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  96: rustc::traits::select::SelectionContext::candidate_from_obligation                                                              
  97: rustc::traits::select::SelectionContext::evaluate_stack                                                                         
  98: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                               
  99: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                     
                                                                                                                                      
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 1.30.0-nightly (4141a4079 2018-09-25) running on x86_64-unknown-linux-gnu                                                 
                                                                                                                                      
error: Could not document `typenum`.                                                                                                  

Caused by:
  process didn't exit successfully: `rustdoc --crate-name typenum /home/arturo/.cargo/registry/src/github.com-1ecc6299db9ec823/typenum-1.10.0/src/lib.rs --cap-lints allow --color always -o /home/arturo/Code/./target/doc -L dependency=/home/arturo/Code/./target/debug/deps` (exit code: 1)

[Havvy]

This is a duplicate of #53505