<p dir="auto">Sorry, since I don't know what causes this, can't be more specific, and don't know if the other bug reports (currently 4 others) are related or have distinct causes.</p>
<p dir="auto">Other issues with the same error:</p>
<ul dir="auto">
<li><a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="13487011" data-permission-text="Title is private" data-url="https://github.com/rust-lang/rust/issues/6000" data-hovercard-type="issue" data-hovercard-url="/rust-lang/rust/issues/6000/hovercard" href="https://github.com/rust-lang/rust/issues/6000">#6000</a></li>
<li><a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="13408175" data-permission-text="Title is private" data-url="https://github.com/rust-lang/rust/issues/5959" data-hovercard-type="issue" data-hovercard-url="/rust-lang/rust/issues/5959/hovercard" href="https://github.com/rust-lang/rust/issues/5959">#5959</a></li>
<li><a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="13743841" data-permission-text="Title is private" data-url="https://github.com/rust-lang/rust/issues/6102" data-hovercard-type="issue" data-hovercard-url="/rust-lang/rust/issues/6102/hovercard" href="https://github.com/rust-lang/rust/issues/6102">#6102</a></li>
<li><a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="14241444" data-permission-text="Title is private" data-url="https://github.com/rust-lang/rust/issues/6440" data-hovercard-type="issue" data-hovercard-url="/rust-lang/rust/issues/6440/hovercard" href="https://github.com/rust-lang/rust/issues/6440">#6440</a></li>
</ul>
<p dir="auto">This is as small as I can get the code:</p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="use core::num::Zero;

pub trait MyTrait {
    pub fn method(&amp;mut self);
}

pub struct MyStruct&lt;U&gt; {
    pub attr: U,
}

pub impl&lt;U: Num&gt; MyStruct&lt;U&gt; {
    pub fn other_method(&amp;mut self) {
        self.attr += Zero::zero();
    }
}

impl MyTrait for MyStruct&lt;f64&gt; {
    pub fn method(&amp;mut self) {
        self.other_method();
    }
}

fn main() {
    let x = MyStruct {attr: 0.0f64};
    let _ = ~x as ~MyTrait;
}"><pre class="notranslate"><code class="notranslate">use core::num::Zero;

pub trait MyTrait {
    pub fn method(&amp;mut self);
}

pub struct MyStruct&lt;U&gt; {
    pub attr: U,
}

pub impl&lt;U: Num&gt; MyStruct&lt;U&gt; {
    pub fn other_method(&amp;mut self) {
        self.attr += Zero::zero();
    }
}

impl MyTrait for MyStruct&lt;f64&gt; {
    pub fn method(&amp;mut self) {
        self.other_method();
    }
}

fn main() {
    let x = MyStruct {attr: 0.0f64};
    let _ = ~x as ~MyTrait;
}
</code></pre></div>
<p dir="auto">To reproduce:<br>
<a href="https://github.com/zwizwa/lars">https://github.com/zwizwa/lars</a><br>
d0a9cae2d174c181f80a3e2716118dd59945be78 bug compiling la.elf<br>
( make la.elf )</p>
<p dir="auto">This is on Debian wheezy/jessie/sid cocktail.</p>
<p dir="auto">rustc 1.0.0-nightly (<a class="commit-link" data-hovercard-type="commit" data-hovercard-url="https://github.com/rust-lang/rust/commit/1d00c545ede609b9d43fdf9f252c15da5a66dac7/hovercard" href="https://github.com/rust-lang/rust/commit/1d00c545ede609b9d43fdf9f252c15da5a66dac7"><tt>1d00c54</tt></a> 2015-01-30 19:56:34 +0000)<br>
binary: rustc<br>
commit-hash: <a class="commit-link" data-hovercard-type="commit" data-hovercard-url="https://github.com/rust-lang/rust/commit/1d00c545ede609b9d43fdf9f252c15da5a66dac7/hovercard" href="https://github.com/rust-lang/rust/commit/1d00c545ede609b9d43fdf9f252c15da5a66dac7"><tt>1d00c54</tt></a><br>
commit-date: 2015-01-30 19:56:34 +0000<br>
host: x86_64-unknown-linux-gnu<br>
release: 1.0.0-nightly</p>
<p dir="auto">[master] tom@zoo:~/lars$ make la.elf<br>
RUST_BACKTRACE=1 rustc la.rs -o la.elf<br>
ERROR:rbml::reader: failed to find block with tag 7<br>
error: internal compiler error: unexpected panic<br>
note: the compiler unexpectedly panicked. this is a bug.<br>
note: we would appreciate a bug report: <a href="http://doc.rust-lang.org/complement-bugreport.html" rel="nofollow">http://doc.rust-lang.org/complement-bugreport.html</a><br>
note: run with <code class="notranslate">RUST_BACKTRACE=1</code> for a backtrace<br>
thread 'rustc' panicked at 'explicit panic', /home/rustbuild/src/rust-buildbot/slave/nightly-dist-rustc-linux/build/src/librbml/lib.rs:266</p>
<p dir="auto">stack backtrace:<br>
1:     0x2b9353530870 - sys::backtrace::write::h26b40214a7757117H8t<br>
2:     0x2b9353553be0 - failure::on_fail::h7a79bf921b6662fbzkB<br>
3:     0x2b93534c01f0 - rt::unwind::begin_unwind_inner::hfe1c0e12f5e834cfAZA<br>
4:     0x2b935a46b550 - rt::unwind::begin_unwind::h13771489483523584678<br>
5:     0x2b935a46a2e0 - reader::get_doc::hca9c74691b431218nLa<br>
6:     0x2b93553feac0 - metadata::decoder::item_type::h11e3fdce04437c2aTqh<br>
7:     0x2b935540fa40 - metadata::decoder::get_type::h81f5136878596756uDh<br>
8:     0x2b93553be9b0 - metadata::csearch::get_type::h9b0725336787e95fjuk<br>
9:     0x2b9353fb38d0 - collect::CollectCtxt&lt;'a, 'tcx&gt;.AstConv&lt;'tcx&gt;::get_item_type_scheme::ha84927afd1cd11a416u<br>
10:     0x2b9353fa2550 - astconv::ast_path_to_ty::h5eef35501e32996d3It<br>
11:     0x2b9353fa3a40 - astconv::ast_ty_to_ty::closure.32670<br>
12:     0x2b9353f3d7f0 - astconv::ast_ty_to_ty::hdfd5055274123a4bN9t<br>
13:     0x2b9353f9c060 - vec::Vec.FromIterator::from_iter::h13503769950079175686<br>
14:     0x2b9353f99cc0 - astconv::convert_angle_bracketed_parameters::h9025012b833df2f4Vit<br>
15:     0x2b9353f3d260 - astconv::ast_path_substs_for_ty::hb223d380e0653eb777s<br>
16:     0x2b9353fa2550 - astconv::ast_path_to_ty::h5eef35501e32996d3It<br>
17:     0x2b9353fa3a40 - astconv::ast_ty_to_ty::closure.32670<br>
18:     0x2b9353f3d7f0 - astconv::ast_ty_to_ty::hdfd5055274123a4bN9t<br>
19:     0x2b9353f9cb70 - astconv::convert_ty_with_lifetime_elision::h6aef1296b36bbcec2mt<br>
20:     0x2b9353fa78d0 - astconv::ty_of_method_or_bare_fn::hfbbddbe9dd8fd2d8Dtu<br>
21:     0x2b9353fa7750 - astconv::ty_of_method::h90bdcfba9a641a98Zru<br>
22:     0x2b9353fcba40 - collect::convert_methods::ty_of_method::h37cc71cdb4ced048svv<br>
23:     0x2b9353fb94e0 - collect::convert::hbd254ededfa34065yyv<br>
24:     0x2b9353ff3670 - check_crate::closure.33797<br>
25:     0x2b9353ff15b0 - check_crate::hd5b0ce5ac42bd86cIEz<br>
26:     0x2b935311bf50 - driver::phase_3_run_analysis_passes::h3a3da09b2eae9713NFa<br>
27:     0x2b9353103330 - driver::compile_input::h802d2a6759ac022fBba<br>
28:     0x2b93531c9230 - run_compiler::h4517938d3296cfc5l9b<br>
29:     0x2b93531c78c0 - thunk::F.Invoke&lt;A, R&gt;::invoke::h5452441173088021345<br>
30:     0x2b93531c67f0 - rt::unwind::try::try_fn::h8490101008730471441<br>
31:     0x2b93535bef60 - rust_try_inner<br>
32:     0x2b93535bef50 - rust_try<br>
33:     0x2b93531c6aa0 - thunk::F.Invoke&lt;A, R&gt;::invoke::h13338196279056651375<br>
34:     0x2b93535403b0 - sys:🧵:thread_start::h395b8c6815673c5cN3w<br>
35:     0x2b935950bfe0 - start_thread<br>
36:     0x2b9353b73c99 - __clone<br>
37:                0x0 - </p>
<p dir="auto">make: *** [la.elf] Error 101</p>
<p dir="auto"><a href="http://doc.rust-lang.org/complement-bugreport.html" rel="nofollow">http://doc.rust-lang.org/complement-bugreport.html</a></p>