Unexpected failure when using ContravariantLifetime

[Denommus]

I'm in Arch Linux x86_64

This is the repository and branch where the bug in question happened: https://github.com/Denommus/xpath-rs/tree/rust-bug

After some study, I found out the smallest code that causes the issue:

use std::kinds::marker::ContravariantLifetime;

struct Foo<'a> {
    foo: *const int,
    lf: ContravariantLifetime<'a>
}

impl<'a> Drop for Foo<'a> {
    fn drop(&mut self) {
    }
}

When trying to cargo build or cargo test it, I get the following error:

   Compiling xpath v0.1.0 (file:/home/yuri/Projetos/PistonDevelopers/xpath-rs)
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://doc.rust-lang.org/complement-bugreport.html
note: run with `RUST_BACKTRACE=1` for a backtrace
task 'rustc' failed at 'index out of bounds: the len is 0 but the index is 0', /build/rust-git/src/rust/src/librustc/middle/subst.rs:405

stack backtrace:
   1:     0x7fd280653440 - rt::backtrace::imp::write::hd9494d95b8843aac9Mp
   2:     0x7fd280656ca0 - <unknown>
   3:     0x7fd280e11660 - unwind::begin_unwind_inner::h86c91288dccdf7edcZd
   4:     0x7fd280e112b0 - unwind::begin_unwind_fmt::h1cb579d85bd16aefFWd
   5:     0x7fd280e11270 - rust_begin_unwind
   6:     0x7fd280e4cde0 - failure::begin_unwind::h4bcdf2c748255fc2srj
   7:     0x7fd280e50670 - failure::fail_bounds_check::hdab871e57fe12ae2Epj
   8:     0x7fd281564060 - <unknown>
   9:     0x7fd281564020 - <unknown>
  10:     0x7fd281562b30 - <unknown>
  11:     0x7fd281562960 - <unknown>
  12:     0x7fd28150af40 - middle::subst::SubstFolder<'a>.TypeFolder::fold_ty::h13798902dd9366ecRMU
  13:     0x7fd28150ae50 - <unknown>
  14:     0x7fd281685fd0 - middle::ty::lookup_field_type::h45aac711c7fa1076qeS
  15:     0x7fd281547e60 - middle::ty::struct_fields::hb5d9b2dc874148eeHmS
  16:     0x7fd2816b10e0 - <unknown>
  17:     0x7fd28164e5d0 - middle::ty::type_contents::hc7f87097be3796b7AsP
  18:     0x7fd2819fa0d0 - <unknown>
  19:     0x7fd2819fcfc0 - middle::kind::check_crate::h567230afc53cc6d1sxQ
  20:     0x7fd281d2da50 - driver::driver::phase_3_run_analysis_passes::h6dd6f772dd74de516Eq
  21:     0x7fd281d28eb0 - driver::driver::compile_input::h74d2c1dd617400e9Mrq
  22:     0x7fd281ddf670 - <unknown>
  23:     0x7fd281ddf580 - <unknown>
  24:     0x7fd281df2dd0 - <unknown>
  25:     0x7fd281df2b60 - <unknown>
  26:     0x7fd283e0ff80 - <unknown>
  27:     0x7fd280e60dc0 - rust_try
  28:     0x7fd280e0e6e0 - unwind::try::h62bccd25ee1c5a2dBNd
  29:     0x7fd280e0e440 - task::Task::run::h899cbe26c861f39cXYc
  30:     0x7fd283e0fd70 - <unknown>
  31:     0x7fd280e106c0 - <unknown>
  32:     0x7fd2800da060 - start_thread
  33:     0x7fd280ad9489 - __clone
  34:                0x0 - <unknown>

Could not execute process `rustc src/lib.rs --crate-name xpath --crate-type lib -g --test --out-dir /home/yuri/Projetos/PistonDevelopers/xpath-rs/target/test -L /home/yuri/Projetos/PistonDevelopers/xpath-rs/target/test -L /home/yuri/Projetos/PistonDevelopers/xpath-rs/target/test/deps` (status=101)

[Denommus]

I have made a case with the smallest code that throws the error. It seems it needs both the ContravariantLifetime and an impl for the trait Drop:
https://gist.github.com/Denommus/3ca9490178387b78dc2f

[sfackler]

Duplicate of #15557. Should be fixed by #15585.