ICE: during cargo doc of nalgreba on stable 1.30.1

[andrewgrz]

ICE during cargo doc of nalgreba crate on stable 1.30.1

librustc/traits/select.rs:2539: Where clause `Binder(<base::default_allocator::DefaultAllocator as base::allocator::Allocator<_, _>>)` was applicable to `Obligation(predicate=Binder(TraitPredicate(<base::default_allocator::DefaultAllocator as base::allocator::Allocator<_, _, _>>)),depth=3)` but now is not

thread '<unnamed>' panicked at 'Box<Any>', librustc_errors/lib.rs:587:9                                                                                      
note: Run with `RUST_BACKTRACE=1` for a backtrace.                                                                                                           
                                                                                                                                                                                                                       
note: rustc 1.30.1 (1433507eb 2018-11-07) running on x86_64-apple-darwin                                                                                     
                                                                                                                                                             
error: Could not document `nalgebra`.  

thread '<unnamed>' panicked at 'Box<Any>', librustc_errors/lib.rs:587:9                                                                                      

stack backtrace:

   0: std::sys::unix::backtrace::tracing::imp::unwind_backtrace                                                                                              
   1: std::sys_common::backtrace::print                                                                                                                      
   2: std::panicking::default_hook::{{closure}}                                                                                                              
   3: std::panicking::default_hook                                                                                                                           
   4: std::panicking::rust_panic_with_hook                                                                                                                   
   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::select::SelectionContext::confirm_candidate                                                                                             
  14: rustc::infer::InferCtxt::probe                                                                                                                         
  15: rustc::traits::select::SelectionContext::evaluate_stack                                                                                                
  16: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                      
  17: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                                                
  18: rustc::infer::InferCtxt::probe                                                                                                                         
  19: <&'a mut I as core::iter::iterator::Iterator>::next                                                                                                    
  20: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                                        
  21: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                                            
  22: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                      
  23: rustc::traits::select::SelectionContext::candidate_from_obligation                                                                                     
  24: rustc::traits::select::SelectionContext::evaluate_stack                                                                                                
  25: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                      
  26: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                                                
  27: rustc::infer::InferCtxt::probe                                                                                                                         
  28: rustc::traits::select::SelectionContext::evaluate_stack                                                                                                
  29: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                      
  30: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                                                
  31: rustc::infer::InferCtxt::probe                                                                                                                         
  32: rustc::traits::select::SelectionContext::evaluate_stack                                                                                                
  33: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                      
  34: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                                                
  35: rustc::traits::select::SelectionContext::evaluate_obligation_recursively                                                                               
  36: rustc::ty::context::tls::with_related_context                                                                                                          
  37: rustc::infer::InferCtxtBuilder::enter                                                                                                                  
  38: rustc_traits::evaluate_obligation::evaluate_obligation                                                                                                 
  39: rustc::ty::query::__query_compute::evaluate_obligation                                                                                                 
  40: rustc::ty::query::<impl rustc::ty::query::config::QueryAccessors<'tcx> for rustc::ty::query::queries::evaluate_obligation<'tcx>>::compute              
  41: rustc::dep_graph::graph::DepGraph::with_task_impl                                                                                                      
  42: rustc::ty::context::tls::with_related_context                                                                                                          
  43: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::force_query_with_job                                                    
  44: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::get_query                                                               
  45: rustc::traits::query::evaluate_obligation::<impl rustc::infer::InferCtxt<'cx, 'gcx, 'tcx>>::evaluate_obligation                                        
  46: rustc::ty::context::tls::with_context::{{closure}}                                                                                                     
  47: rustdoc::clean::blanket_impl::BlanketImplFinder::get_blanket_impls::{{closure}}                                                                        
  48: rustc::ty::trait_def::<impl rustc::ty::context::TyCtxt<'a, 'gcx, 'tcx>>::for_each_relevant_impl                                                        
  49: rustdoc::clean::blanket_impl::BlanketImplFinder::get_blanket_impls                                                                                     
  50: rustdoc::clean::def_ctor::get_def_from_node_id                                                                                                         
  51: <rustdoc::doctree::Struct as rustdoc::clean::Clean<alloc::vec::Vec<rustdoc::clean::Item>>>::clean                                                      
  52: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::spec_extend                                                                                      
  53: <rustdoc::doctree::Module as rustdoc::clean::Clean<rustdoc::clean::Item>>::clean                                                                       
  54: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::spec_extend                                                                                      
  55: <rustdoc::doctree::Module as rustdoc::clean::Clean<rustdoc::clean::Item>>::clean                                                                       
  56: <rustdoc::visit_ast::RustdocVisitor<'a, 'tcx, 'rcx, 'cstore> as rustdoc::clean::Clean<rustdoc::clean::Crate>>::clean                                   
  57: rustdoc::core::run_core::{{closure}}::{{closure}}                                                                                                      
  58: rustc::ty::context::tls::enter_context                                                                                                                 
  59: <std::thread::local::LocalKey<T>>::with                                                                                                                
  60: rustc::ty::context::TyCtxt::create_and_enter                                                                                                           
  61: rustc_driver::driver::phase_3_run_analysis_passes                                                                                                      
  62: <scoped_tls::ScopedKey<T>>::set                                                                                                                        
  63: rustdoc::core::run_core                                                                                                                                
  64: <scoped_tls::ScopedKey<T>>::set                                                                                                                        
  65: syntax::with_globals                                                                                                                                   
  66: <std::panic::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once                                                                        
  67: std::panicking::try::do_call                                                                                                                           
  68: __rust_maybe_catch_panic                                                                                                                               
  69: rustc_driver::monitor                                                                                                                                  
  70: rustdoc::rust_input                                                                                                                                    
  71: rustdoc::main_args                                                                                                                                     
  72: <scoped_tls::ScopedKey<T>>::set                                 

rustc --version --verbose

rustc 1.30.1 (1433507eb 2018-11-07)
binary: rustc
commit-hash: 1433507eba7d1a114e4c6f27ae0e1a74f60f20de
commit-date: 2018-11-07
host: x86_64-apple-darwin
release: 1.30.1
LLVM version: 8.0

[Aaron1011]

Duplicate of #54744