<p dir="auto">My code is certainly broken, but it triggered an ICE.  Apologies if this is a duplicate!  If the triggering code is useful, I've pushed a branch with the triggering material: <a href="https://github.com/spacejam/rust-rocksdb/tree/tan_ICE">https://github.com/spacejam/rust-rocksdb/tree/tan_ICE</a></p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="rustc 0.13.0-nightly (c7dd3c4d6 2015-01-05 23:51:00 +0000)
binary: rustc
commit-hash: c7dd3c4d69aee1c4ad8cc220c194b176bba2ab62
commit-date: 2015-01-05 23:51:00 +0000
host: x86_64-apple-darwin
release: 0.13.0-nightly

...

   Compiling rocksdb v0.0.2 (file:///Users/tan/code/rust-rocksdb)
     Running `rustc /Users/tan/code/rust-rocksdb/src/lib.rs --crate-name rocksdb --crate-type lib -g -C metadata=6653d8e8924e4f84 -C extra-filename=-6653d8e8924e4f84 --out-dir /Users/tan/code/rust-rocksdb/target --emit=dep-info,link -L /Users/tan/code/rust-rocksdb/target -L /Users/tan/code/rust-rocksdb/target/deps`
/Users/tan/code/rust-rocksdb/src/rocksdb.rs:592:1: 621:2 error: internal compiler error: impl `VtableImpl(impl_def_id=DefId { krate: 0, node: 3108 }:rocksdb::&amp;'a mut MergeOperands&lt;'a&gt;.Iterator, substs=Substs[types=[[];[];[]], regions=[['_#0r];[];[]]], nested=[[];[];[]])` did not contain projection for `Obligation(predicate=&lt;&amp;'a mut rocksdb::MergeOperands&lt;'a&gt; as TraitRef(&amp;'a mut rocksdb::MergeOperands&lt;'a&gt;, core::iter::Iterator)&gt;::Item,depth=0)`
/Users/tan/code/rust-rocksdb/src/rocksdb.rs:592 impl&lt;'a&gt; Iterator for &amp;'a mut MergeOperands&lt;'a&gt; {
/Users/tan/code/rust-rocksdb/src/rocksdb.rs:593     fn next(&amp;mut self) -&gt; Option&lt;&amp;'a [u8]&gt; {
/Users/tan/code/rust-rocksdb/src/rocksdb.rs:594         use std::raw::Slice;
/Users/tan/code/rust-rocksdb/src/rocksdb.rs:595         match self.cursor == self.num_operands {
/Users/tan/code/rust-rocksdb/src/rocksdb.rs:596             true =&gt; None,
/Users/tan/code/rust-rocksdb/src/rocksdb.rs:597             false =&gt; {
                                                ...
note: the compiler unexpectedly panicked. this is a bug.
note: we would appreciate a bug report: http://doc.rust-lang.org/complement-bugreport.html
note: run with `RUST_BACKTRACE=1` for a backtrace
thread 'rustc' panicked at 'Box&lt;Any&gt;', /Users/rustbuild/src/rust-buildbot/slave/nightly-dist-rustc-mac/build/src/libsyntax/diagnostic.rs:123

stack backtrace:
   1:        0x106f7d5e5 - sys::backtrace::write::h98e4664f4f31dc8eiTs
   2:        0x106fa2f4f - failure::on_fail::h15cffea110d6009eKVy
   3:        0x106f0840a - rt::unwind::begin_unwind_inner::h9de529c6f705175fKDy
   4:        0x104c09dc7 - rt::unwind::begin_unwind::h8742058877264024887
   5:        0x104c09d5c - diagnostic::SpanHandler::span_bug::h3bc28b7b3bcff0610kF
   6:        0x1043a1603 - middle::traits::project::project_type::h5ce8ef2558d93d50zQP
   7:        0x10439cb5e - middle::traits::project::opt_normalize_projection_type::hcee84b18f83e8d45CIP
   8:        0x10438ae43 - middle::traits::project::normalize_projection_type::h7c69afde591a893ddHP
   9:        0x10439df9f - middle::traits::project::AssociatedTypeNormalizer&lt;'a, 'b, 'tcx&gt;.TypeFolder&lt;'tcx&gt;::fold_ty::hc4b6ba01061942daOFP
  10:        0x103cab937 - middle::ty_fold::TypeFolder::fold_trait_ref::h6518936090498913440
  11:        0x103cac3a1 - middle::ty_fold::VecPerParamSpace&lt;T&gt;.TypeFoldable&lt;'tcx&gt;::fold_with::h10053445313753109854
  12:        0x103cc73b4 - check::FnCtxt&lt;'a, 'tcx&gt;::instantiate_bounds::h31abbc782f1f47fd1kl
  13:        0x103cdfdfd - check::wf::CheckTypeWellFormedVisitor&lt;'ccx, 'tcx&gt;::with_fcx::h1819609048976829711
  14:        0x103ce2620 - check::wf::CheckTypeWellFormedVisitor&lt;'ccx, 'tcx&gt;.Visitor&lt;'v&gt;::visit_item::h2bf7c5e628314514tki
  15:        0x103ce546f - visit::walk_mod::h14492313709251987009
  16:        0x103ce2fac - check::wf::CheckTypeWellFormedVisitor&lt;'ccx, 'tcx&gt;.Visitor&lt;'v&gt;::visit_item::h2bf7c5e628314514tki
  17:        0x103de546b - check_crate::unboxed_closure.39887
  18:        0x103de0d53 - check_crate::hbc0ab8570a19149famx
  19:        0x103711292 - driver::phase_3_run_analysis_passes::h61da41ec58961d9bSva
  20:        0x1036fdcac - driver::compile_input::h6ba151de4af50ce2vba
  21:        0x1037c0c13 - thunk::F.Invoke&lt;A, R&gt;::invoke::h15890902738341362910
  22:        0x1037bdd70 - rt::unwind::try::try_fn::h15939753852117214544
  23:        0x107008009 - rust_try_inner
  24:        0x107007ff6 - rust_try
  25:        0x1037be4b6 - thunk::F.Invoke&lt;A, R&gt;::invoke::h14011449182044061502
  26:        0x106f8ea34 - sys::thread::thread_start::h4e93ea2350249d53kGv
  27:     0x7fff8dcfa2fc - _pthread_body
  28:     0x7fff8dcfa279 - _pthread_body

Could not compile `rocksdb`.

Caused by:
  Process didn't exit successfully: `rustc /Users/tan/code/rust-rocksdb/src/lib.rs --crate-name rocksdb --crate-type lib -g -C metadata=6653d8e8924e4f84 -C extra-filename=-6653d8e8924e4f84 --out-dir /Users/tan/code/rust-rocksdb/target --emit=dep-info,link -L /Users/tan/code/rust-rocksdb/target -L /Users/tan/code/rust-rocksdb/target/deps` (status=101)"><pre class="notranslate"><code class="notranslate">rustc 0.13.0-nightly (c7dd3c4d6 2015-01-05 23:51:00 +0000)
binary: rustc
commit-hash: c7dd3c4d69aee1c4ad8cc220c194b176bba2ab62
commit-date: 2015-01-05 23:51:00 +0000
host: x86_64-apple-darwin
release: 0.13.0-nightly

...

   Compiling rocksdb v0.0.2 (file:///Users/tan/code/rust-rocksdb)
     Running `rustc /Users/tan/code/rust-rocksdb/src/lib.rs --crate-name rocksdb --crate-type lib -g -C metadata=6653d8e8924e4f84 -C extra-filename=-6653d8e8924e4f84 --out-dir /Users/tan/code/rust-rocksdb/target --emit=dep-info,link -L /Users/tan/code/rust-rocksdb/target -L /Users/tan/code/rust-rocksdb/target/deps`
/Users/tan/code/rust-rocksdb/src/rocksdb.rs:592:1: 621:2 error: internal compiler error: impl `VtableImpl(impl_def_id=DefId { krate: 0, node: 3108 }:rocksdb::&amp;'a mut MergeOperands&lt;'a&gt;.Iterator, substs=Substs[types=[[];[];[]], regions=[['_#0r];[];[]]], nested=[[];[];[]])` did not contain projection for `Obligation(predicate=&lt;&amp;'a mut rocksdb::MergeOperands&lt;'a&gt; as TraitRef(&amp;'a mut rocksdb::MergeOperands&lt;'a&gt;, core::iter::Iterator)&gt;::Item,depth=0)`
/Users/tan/code/rust-rocksdb/src/rocksdb.rs:592 impl&lt;'a&gt; Iterator for &amp;'a mut MergeOperands&lt;'a&gt; {
/Users/tan/code/rust-rocksdb/src/rocksdb.rs:593     fn next(&amp;mut self) -&gt; Option&lt;&amp;'a [u8]&gt; {
/Users/tan/code/rust-rocksdb/src/rocksdb.rs:594         use std::raw::Slice;
/Users/tan/code/rust-rocksdb/src/rocksdb.rs:595         match self.cursor == self.num_operands {
/Users/tan/code/rust-rocksdb/src/rocksdb.rs:596             true =&gt; None,
/Users/tan/code/rust-rocksdb/src/rocksdb.rs:597             false =&gt; {
                                                ...
note: the compiler unexpectedly panicked. this is a bug.
note: we would appreciate a bug report: http://doc.rust-lang.org/complement-bugreport.html
note: run with `RUST_BACKTRACE=1` for a backtrace
thread 'rustc' panicked at 'Box&lt;Any&gt;', /Users/rustbuild/src/rust-buildbot/slave/nightly-dist-rustc-mac/build/src/libsyntax/diagnostic.rs:123

stack backtrace:
   1:        0x106f7d5e5 - sys::backtrace::write::h98e4664f4f31dc8eiTs
   2:        0x106fa2f4f - failure::on_fail::h15cffea110d6009eKVy
   3:        0x106f0840a - rt::unwind::begin_unwind_inner::h9de529c6f705175fKDy
   4:        0x104c09dc7 - rt::unwind::begin_unwind::h8742058877264024887
   5:        0x104c09d5c - diagnostic::SpanHandler::span_bug::h3bc28b7b3bcff0610kF
   6:        0x1043a1603 - middle::traits::project::project_type::h5ce8ef2558d93d50zQP
   7:        0x10439cb5e - middle::traits::project::opt_normalize_projection_type::hcee84b18f83e8d45CIP
   8:        0x10438ae43 - middle::traits::project::normalize_projection_type::h7c69afde591a893ddHP
   9:        0x10439df9f - middle::traits::project::AssociatedTypeNormalizer&lt;'a, 'b, 'tcx&gt;.TypeFolder&lt;'tcx&gt;::fold_ty::hc4b6ba01061942daOFP
  10:        0x103cab937 - middle::ty_fold::TypeFolder::fold_trait_ref::h6518936090498913440
  11:        0x103cac3a1 - middle::ty_fold::VecPerParamSpace&lt;T&gt;.TypeFoldable&lt;'tcx&gt;::fold_with::h10053445313753109854
  12:        0x103cc73b4 - check::FnCtxt&lt;'a, 'tcx&gt;::instantiate_bounds::h31abbc782f1f47fd1kl
  13:        0x103cdfdfd - check::wf::CheckTypeWellFormedVisitor&lt;'ccx, 'tcx&gt;::with_fcx::h1819609048976829711
  14:        0x103ce2620 - check::wf::CheckTypeWellFormedVisitor&lt;'ccx, 'tcx&gt;.Visitor&lt;'v&gt;::visit_item::h2bf7c5e628314514tki
  15:        0x103ce546f - visit::walk_mod::h14492313709251987009
  16:        0x103ce2fac - check::wf::CheckTypeWellFormedVisitor&lt;'ccx, 'tcx&gt;.Visitor&lt;'v&gt;::visit_item::h2bf7c5e628314514tki
  17:        0x103de546b - check_crate::unboxed_closure.39887
  18:        0x103de0d53 - check_crate::hbc0ab8570a19149famx
  19:        0x103711292 - driver::phase_3_run_analysis_passes::h61da41ec58961d9bSva
  20:        0x1036fdcac - driver::compile_input::h6ba151de4af50ce2vba
  21:        0x1037c0c13 - thunk::F.Invoke&lt;A, R&gt;::invoke::h15890902738341362910
  22:        0x1037bdd70 - rt::unwind::try::try_fn::h15939753852117214544
  23:        0x107008009 - rust_try_inner
  24:        0x107007ff6 - rust_try
  25:        0x1037be4b6 - thunk::F.Invoke&lt;A, R&gt;::invoke::h14011449182044061502
  26:        0x106f8ea34 - sys::thread::thread_start::h4e93ea2350249d53kGv
  27:     0x7fff8dcfa2fc - _pthread_body
  28:     0x7fff8dcfa279 - _pthread_body

Could not compile `rocksdb`.

Caused by:
  Process didn't exit successfully: `rustc /Users/tan/code/rust-rocksdb/src/lib.rs --crate-name rocksdb --crate-type lib -g -C metadata=6653d8e8924e4f84 -C extra-filename=-6653d8e8924e4f84 --out-dir /Users/tan/code/rust-rocksdb/target --emit=dep-info,link -L /Users/tan/code/rust-rocksdb/target -L /Users/tan/code/rust-rocksdb/target/deps` (status=101)
</code></pre></div>
<p dir="auto">This code</p>
<div class="highlight highlight-source-rust notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="trait ListItem&lt;'a&gt; {
    fn list_name() -&gt; &amp;'a str;
}

struct List&lt;'a, T: ListItem&lt;'a&gt;&gt; {
    slice: &amp;'a [T]
}

impl&lt;'a, T: ListItem&lt;'a&gt;&gt; Collection for List&lt;'a, T&gt; {
    fn len(&amp;self) -&gt; uint {
        0
    }
}

fn main() {
}"><pre class="notranslate"><span class="pl-k">trait</span> <span class="pl-smi">ListItem</span><span class="pl-kos">&lt;</span><span class="pl-c1">'</span><span class="pl-ent">a</span><span class="pl-kos">&gt;</span> <span class="pl-kos">{</span>
    <span class="pl-k">fn</span> <span class="pl-en">list_name</span><span class="pl-kos">(</span><span class="pl-kos">)</span> -&gt; <span class="pl-c1">&amp;</span><span class="pl-c1">'</span><span class="pl-ent">a</span> <span class="pl-smi">str</span><span class="pl-kos">;</span>
<span class="pl-kos">}</span>

<span class="pl-k">struct</span> <span class="pl-smi">List</span><span class="pl-kos">&lt;</span><span class="pl-c1">'</span><span class="pl-ent">a</span><span class="pl-kos">,</span> <span class="pl-smi">T</span><span class="pl-kos">:</span> <span class="pl-smi">ListItem</span><span class="pl-kos">&lt;</span><span class="pl-c1">'</span><span class="pl-ent">a</span><span class="pl-kos">&gt;</span><span class="pl-kos">&gt;</span> <span class="pl-kos">{</span>
    <span class="pl-c1">slice</span><span class="pl-kos">:</span> <span class="pl-c1">&amp;</span><span class="pl-c1">'</span><span class="pl-ent">a</span> <span class="pl-kos">[</span><span class="pl-smi">T</span><span class="pl-kos">]</span>
<span class="pl-kos">}</span>

<span class="pl-k">impl</span><span class="pl-kos">&lt;</span><span class="pl-c1">'</span><span class="pl-ent">a</span><span class="pl-kos">,</span> <span class="pl-smi">T</span><span class="pl-kos">:</span> <span class="pl-smi">ListItem</span><span class="pl-kos">&lt;</span><span class="pl-c1">'</span><span class="pl-ent">a</span><span class="pl-kos">&gt;</span><span class="pl-kos">&gt;</span> <span class="pl-smi">Collection</span> <span class="pl-k">for</span> <span class="pl-smi">List</span><span class="pl-kos">&lt;</span><span class="pl-c1">'</span><span class="pl-ent">a</span><span class="pl-kos">,</span> <span class="pl-smi">T</span><span class="pl-kos">&gt;</span> <span class="pl-kos">{</span>
    <span class="pl-k">fn</span> <span class="pl-en">len</span><span class="pl-kos">(</span><span class="pl-c1">&amp;</span><span class="pl-smi">self</span><span class="pl-kos">)</span> -&gt; <span class="pl-smi">uint</span> <span class="pl-kos">{</span>
        <span class="pl-c1">0</span>
    <span class="pl-kos">}</span>
<span class="pl-kos">}</span>

<span class="pl-k">fn</span> <span class="pl-en">main</span><span class="pl-kos">(</span><span class="pl-kos">)</span> <span class="pl-kos">{</span>
<span class="pl-kos">}</span></pre></div>
<p dir="auto">Causes this ICE</p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="test.rs:9:1: 13:2 error: internal compiler error: cannot relate bound region: ReEarlyBound(29, TypeSpace, 0, 'a) &lt;= ReFree(25, BrNamed(syntax::ast::DefId{krate: 0u32, node: 29u32}, 'a))
test.rs:9 impl&lt;'a, T: ListItem&lt;'a&gt;&gt; Collection for List&lt;'a, T&gt; {
test.rs:10     fn len(&amp;self) -&gt; uint {
test.rs:11         0
test.rs:12     }
test.rs:13 }"><pre class="notranslate"><code class="notranslate">test.rs:9:1: 13:2 error: internal compiler error: cannot relate bound region: ReEarlyBound(29, TypeSpace, 0, 'a) &lt;= ReFree(25, BrNamed(syntax::ast::DefId{krate: 0u32, node: 29u32}, 'a))
test.rs:9 impl&lt;'a, T: ListItem&lt;'a&gt;&gt; Collection for List&lt;'a, T&gt; {
test.rs:10     fn len(&amp;self) -&gt; uint {
test.rs:11         0
test.rs:12     }
test.rs:13 }
</code></pre></div>
<p dir="auto">RUSTC_BACKTRACE=1 output</p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="task 'rustc' failed at 'Box&lt;Any&gt;', /home/rustbuild/src/rust-buildbot/slave/nightly-linux/build/src/libsyntax/ast_util.rs:776

stack backtrace:
   1:     0x7f998a9c7460 - rt::backtrace::imp::write::h18b753371f3f9ce4UYq
   2:     0x7f998a9ca610 - failure::on_fail::h8b148d7ea01ad414Bkr
   3:     0x7f998b195510 - unwind::begin_unwind_inner::h95325e05b1285682pie
   4:     0x7f9987478890 - unwind::begin_unwind::h11886784450375267201
   5:     0x7f99874787e0 - diagnostic::SpanHandler::span_bug::h7e01102b77dc6ccfdqF
   6:     0x7f998b720150 - driver::session::Session::span_bug::h64271874b664f154Jty
   7:     0x7f998bbb2800 - middle::typeck::infer::region_inference::RegionVarBindings&lt;'a&gt;::make_subregion::h4d9c94c5e2a52f9fXj4
   8:     0x7f998bb9a490 - middle::typeck::infer::sub::Sub&lt;'f&gt;.Combine::regions::h01a279f6c3dd5fbfQJ6
   9:     0x7f998bb9a800 - middle::typeck::infer::sub::Sub&lt;'f&gt;.Combine::contraregions::hdda7ddc886cfbc7fgJ6
  10:     0x7f998bbc42c0 - middle::typeck::infer::combine::Combine::substs::h6143560546622796331
  11:     0x7f998bbecee0 - middle::typeck::infer::mk_sub_trait_refs::closure.126361
  12:     0x7f998bbecc10 - middle::typeck::infer::InferCtxt&lt;'a&gt;::commit_if_ok::closure.126353
  13:     0x7f998bbeca60 - middle::typeck::infer::InferCtxt&lt;'a&gt;::commit_unconditionally::h84882112510864248
  14:     0x7f998ba8fa40 - middle::typeck::infer::mk_sub_trait_refs::hd5dd1a653add0c8fLFb
  15:     0x7f998ba8f3b0 - middle::typeck::check::vtable::relate_trait_refs::hd2353c5413fef28cRpK
  16:     0x7f998ba939a0 - middle::typeck::check::vtable::lookup_vtable_from_bounds::closure.121800
  17:     0x7f998ba5ce10 - middle::ty::each_bound_trait_and_supertraits::h200637ff3ab6a085cvH
  18:     0x7f998ba8d630 - middle::typeck::check::vtable::lookup_vtables_for_param::closure.121773
  19:     0x7f998ba5ce10 - middle::ty::each_bound_trait_and_supertraits::h200637ff3ab6a085cvH
  20:     0x7f998ba8d0b0 - middle::typeck::check::vtable::lookup_vtables_for_param::h4434ba5a22fe5e6dibK
  21:     0x7f998ba8b0b0 - middle::typeck::check::vtable::lookup_vtables::h4da8aebbea78be1dk5J
  22:     0x7f998b812080 - middle::typeck::check::vtable::check_param_bounds::h504b9dc2d6d8e4a7zLL
  23:     0x7f998b811d90 - middle::kind::check_bounds_on_structs_or_enums_in_type_if_possible::closure.110610
  24:     0x7f998ba59290 - middle::ty::walk_ty::closure.120581
  25:     0x7f998b7f80b0 - middle::ty::maybe_walk_ty::h867184bbacff06f7dOD
  26:     0x7f998b808c30 - middle::kind::check_bounds_on_structs_or_enums_in_type_if_possible::h826a0efdd31cf77fSPw
  27:     0x7f998b8007a0 - middle::kind::check_item::h5a6fe2387dac9563Agw
  28:     0x7f998b8041c0 - middle::kind::check_crate::h3dde9f98fbaa1ff7a4v
  29:     0x7f998b56e940 - util::common::time::h630719443776585502
  30:     0x7f998bd92a60 - driver::driver::phase_3_run_analysis_passes::ha7a07a1607fe33bfuWw
  31:     0x7f998bd8dc00 - driver::driver::compile_input::h99199d0ae0e721f6AIw
  32:     0x7f998be21cd0 - driver::run_compiler::h23c8c067c597dffdtfA
  33:     0x7f998be21be0 - driver::main_args::closure.137253
  34:     0x7f998be33ab0 - task::TaskBuilder&lt;S&gt;::try_future::closure.138373
  35:     0x7f998be338b0 - task::TaskBuilder&lt;S&gt;::spawn_internal::closure.138350
  36:     0x7f998c855dc0 - task::spawn_opts::closure.8268
  37:     0x7f998b1eda90 - rust_try_inner
  38:     0x7f998b1eda80 - rust_try
  39:     0x7f998b192b80 - unwind::try::h897530fe9a04a6a3F6d
  40:     0x7f998b192920 - task::Task::run::ha1dfd395f272d95cZcd
  41:     0x7f998c855b80 - task::spawn_opts::closure.8214
  42:     0x7f998b194760 - thread::thread_start::hb2d1975aedb783e1LBd
  43:     0x7f998a45f060 - start_thread
  44:     0x7f998ae62489 - __clone
  45:                0x0 - &lt;unknown&gt;"><pre class="notranslate"><code class="notranslate">task 'rustc' failed at 'Box&lt;Any&gt;', /home/rustbuild/src/rust-buildbot/slave/nightly-linux/build/src/libsyntax/ast_util.rs:776

stack backtrace:
   1:     0x7f998a9c7460 - rt::backtrace::imp::write::h18b753371f3f9ce4UYq
   2:     0x7f998a9ca610 - failure::on_fail::h8b148d7ea01ad414Bkr
   3:     0x7f998b195510 - unwind::begin_unwind_inner::h95325e05b1285682pie
   4:     0x7f9987478890 - unwind::begin_unwind::h11886784450375267201
   5:     0x7f99874787e0 - diagnostic::SpanHandler::span_bug::h7e01102b77dc6ccfdqF
   6:     0x7f998b720150 - driver::session::Session::span_bug::h64271874b664f154Jty
   7:     0x7f998bbb2800 - middle::typeck::infer::region_inference::RegionVarBindings&lt;'a&gt;::make_subregion::h4d9c94c5e2a52f9fXj4
   8:     0x7f998bb9a490 - middle::typeck::infer::sub::Sub&lt;'f&gt;.Combine::regions::h01a279f6c3dd5fbfQJ6
   9:     0x7f998bb9a800 - middle::typeck::infer::sub::Sub&lt;'f&gt;.Combine::contraregions::hdda7ddc886cfbc7fgJ6
  10:     0x7f998bbc42c0 - middle::typeck::infer::combine::Combine::substs::h6143560546622796331
  11:     0x7f998bbecee0 - middle::typeck::infer::mk_sub_trait_refs::closure.126361
  12:     0x7f998bbecc10 - middle::typeck::infer::InferCtxt&lt;'a&gt;::commit_if_ok::closure.126353
  13:     0x7f998bbeca60 - middle::typeck::infer::InferCtxt&lt;'a&gt;::commit_unconditionally::h84882112510864248
  14:     0x7f998ba8fa40 - middle::typeck::infer::mk_sub_trait_refs::hd5dd1a653add0c8fLFb
  15:     0x7f998ba8f3b0 - middle::typeck::check::vtable::relate_trait_refs::hd2353c5413fef28cRpK
  16:     0x7f998ba939a0 - middle::typeck::check::vtable::lookup_vtable_from_bounds::closure.121800
  17:     0x7f998ba5ce10 - middle::ty::each_bound_trait_and_supertraits::h200637ff3ab6a085cvH
  18:     0x7f998ba8d630 - middle::typeck::check::vtable::lookup_vtables_for_param::closure.121773
  19:     0x7f998ba5ce10 - middle::ty::each_bound_trait_and_supertraits::h200637ff3ab6a085cvH
  20:     0x7f998ba8d0b0 - middle::typeck::check::vtable::lookup_vtables_for_param::h4434ba5a22fe5e6dibK
  21:     0x7f998ba8b0b0 - middle::typeck::check::vtable::lookup_vtables::h4da8aebbea78be1dk5J
  22:     0x7f998b812080 - middle::typeck::check::vtable::check_param_bounds::h504b9dc2d6d8e4a7zLL
  23:     0x7f998b811d90 - middle::kind::check_bounds_on_structs_or_enums_in_type_if_possible::closure.110610
  24:     0x7f998ba59290 - middle::ty::walk_ty::closure.120581
  25:     0x7f998b7f80b0 - middle::ty::maybe_walk_ty::h867184bbacff06f7dOD
  26:     0x7f998b808c30 - middle::kind::check_bounds_on_structs_or_enums_in_type_if_possible::h826a0efdd31cf77fSPw
  27:     0x7f998b8007a0 - middle::kind::check_item::h5a6fe2387dac9563Agw
  28:     0x7f998b8041c0 - middle::kind::check_crate::h3dde9f98fbaa1ff7a4v
  29:     0x7f998b56e940 - util::common::time::h630719443776585502
  30:     0x7f998bd92a60 - driver::driver::phase_3_run_analysis_passes::ha7a07a1607fe33bfuWw
  31:     0x7f998bd8dc00 - driver::driver::compile_input::h99199d0ae0e721f6AIw
  32:     0x7f998be21cd0 - driver::run_compiler::h23c8c067c597dffdtfA
  33:     0x7f998be21be0 - driver::main_args::closure.137253
  34:     0x7f998be33ab0 - task::TaskBuilder&lt;S&gt;::try_future::closure.138373
  35:     0x7f998be338b0 - task::TaskBuilder&lt;S&gt;::spawn_internal::closure.138350
  36:     0x7f998c855dc0 - task::spawn_opts::closure.8268
  37:     0x7f998b1eda90 - rust_try_inner
  38:     0x7f998b1eda80 - rust_try
  39:     0x7f998b192b80 - unwind::try::h897530fe9a04a6a3F6d
  40:     0x7f998b192920 - task::Task::run::ha1dfd395f272d95cZcd
  41:     0x7f998c855b80 - task::spawn_opts::closure.8214
  42:     0x7f998b194760 - thread::thread_start::hb2d1975aedb783e1LBd
  43:     0x7f998a45f060 - start_thread
  44:     0x7f998ae62489 - __clone
  45:                0x0 - &lt;unknown&gt;
</code></pre></div>
<p dir="auto">rustc -v: <code class="notranslate">rustc 0.12.0-pre-nightly (833277e2d 2014-08-25 00:00:59 +0000)</code><br>
uname -a: <code class="notranslate">Linux  3.16.1-1-ARCH #1 SMP PREEMPT Thu Aug 14 07:40:19 CEST 2014 x86_64 GNU/Linux</code></p>