ICE in translation phase while using DST: "Invalid operand types for ICmp instruction"

[japaric]

I was playing with DST by reimplementing the str primitive as a struct Str([u8]), but hit an ICE while testing.

The code is in this gist

Output

$ RUST_BACKTRACE=1 rustc dstr.rs
rustc: /var/tmp/paludis/build/dev-lang-rust-scm/work/rust-scm/src/llvm/include/llvm/IR/Instructions.h:1001: void llvm::ICmpInst::AssertOK(): Assertion `(getOperand(0)->getType()->isIntOrIntVectorTy() || getOperand(0)->getType()->isPtrOrPtrVectorTy()) && "Invalid operand types for ICmp instruction"' failed.
[1]    30465 abort (core dumped)  rustc dstr.rs

Backtrace

#0  0x00007ffff62698a7 in raise () from /lib64/libc.so.6
#1  0x00007ffff626ac3a in abort () from /lib64/libc.so.6
#2  0x00007ffff62627fd in __assert_fail_base () from /lib64/libc.so.6
#3  0x00007ffff62628b2 in __assert_fail () from /lib64/libc.so.6
#4  0x00007ffff3918608 in ?? () from /usr/lib64/librustc_llvm-4e7c5e5c.so
#5  0x00007ffff457b527 in LLVMBuildICmp () from /usr/lib64/librustc_llvm-4e7c5e5c.so
#6  0x00007ffff6e54a7f in middle::trans::builder::Builder$LT$$x27a$C$$x20$x27tcx$GT$::icmp::h4aa6ae27f256fabePje () from /usr/lib64/librustc-4e7c5e5c.so
#7  0x00007ffff6dd7830 in middle::trans::adt::trans_get_discr::ha443b7b22a4caa61VFv () from /usr/lib64/librustc-4e7c5e5c.so
#8  0x00007ffff6e8a6f8 in ?? () from /usr/lib64/librustc-4e7c5e5c.so
#9  0x00007ffff6e87858 in ?? () from /usr/lib64/librustc-4e7c5e5c.so
#10 0x00007ffff6e17603 in middle::trans::_match::trans_match::he701ef37a38be851Agk () from /usr/lib64/librustc-4e7c5e5c.so
#11 0x00007ffff6e05630 in ?? () from /usr/lib64/librustc-4e7c5e5c.so
#12 0x00007ffff6dc85fd in middle::trans::expr::trans_into::h8ae2b7a3d17060a8CD4 () from /usr/lib64/librustc-4e7c5e5c.so
#13 0x00007ffff6dc895f in middle::trans::controlflow::trans_block::h436e3d0d9803e356ST0 () from /usr/lib64/librustc-4e7c5e5c.so
#14 0x00007ffff6e713f8 in middle::trans::base::trans_closure::h231ca5ccc1f2e69at0g () from /usr/lib64/librustc-4e7c5e5c.so
#15 0x00007ffff6dbb07a in middle::trans::base::trans_fn::hadaba5b2481570fcRbh () from /usr/lib64/librustc-4e7c5e5c.so
#16 0x00007ffff6dbd4ce in middle::trans::monomorphize::monomorphic_fn::h4563fac28419b936ik0 () from /usr/lib64/librustc-4e7c5e5c.so
#17 0x00007ffff6df0b7c in middle::trans::callee::trans_fn_ref_with_substs::h8eabc21193fe07d6Hx3 () from /usr/lib64/librustc-4e7c5e5c.so
#18 0x00007ffff6dedd70 in middle::trans::callee::trans_fn_ref::h8d74fc054b8b7de4xl3 () from /usr/lib64/librustc-4e7c5e5c.so
#19 0x00007ffff6dd1ffc in middle::trans::meth::trans_method_callee::hbc28e9cef099c699gom () from /usr/lib64/librustc-4e7c5e5c.so
#20 0x00007ffff6df6dae in ?? () from /usr/lib64/librustc-4e7c5e5c.so
#21 0x00007ffff6dd0221 in middle::trans::callee::trans_call_inner::ha74736412897064crT3 () from /usr/lib64/librustc-4e7c5e5c.so
#22 0x00007ffff6df6bb1 in middle::trans::callee::trans_method_call::h99ff4f13e516b804TO3 () from /usr/lib64/librustc-4e7c5e5c.so
#23 0x00007ffff6e05136 in ?? () from /usr/lib64/librustc-4e7c5e5c.so
#24 0x00007ffff6e03e73 in ?? () from /usr/lib64/librustc-4e7c5e5c.so
#25 0x00007ffff6dc9a0c in middle::trans::expr::trans::h159a4d5c8110b09awH4 () from /usr/lib64/librustc-4e7c5e5c.so
#26 0x00007ffff6e662f3 in middle::trans::_match::store_local::hd8b63d9160463155Vtk () from /usr/lib64/librustc-4e7c5e5c.so
#27 0x00007ffff6dc7b58 in middle::trans::base::init_local::h4a9b7e04850a284b38f () from /usr/lib64/librustc-4e7c5e5c.so
#28 0x00007ffff6dc6f90 in middle::trans::controlflow::trans_stmt::h89e8a60881dc9d7cMO0 () from /usr/lib64/librustc-4e7c5e5c.so
#29 0x00007ffff6dc8868 in middle::trans::controlflow::trans_block::h436e3d0d9803e356ST0 () from /usr/lib64/librustc-4e7c5e5c.so
#30 0x00007ffff6e713f8 in middle::trans::base::trans_closure::h231ca5ccc1f2e69at0g () from /usr/lib64/librustc-4e7c5e5c.so
#31 0x00007ffff6dbb07a in middle::trans::base::trans_fn::hadaba5b2481570fcRbh () from /usr/lib64/librustc-4e7c5e5c.so
#32 0x00007ffff6db86df in middle::trans::base::trans_item::hfe038ac56abea028avh () from /usr/lib64/librustc-4e7c5e5c.so
#33 0x00007ffff6e7ab99 in middle::trans::base::trans_crate::h88329c3ddbae368c1si () from /usr/lib64/librustc-4e7c5e5c.so
#34 0x00007ffff72c8d15 in driver::driver::phase_4_translate_to_llvm::h16ffd3985d271c57d5z () from /usr/lib64/librustc-4e7c5e5c.so
#35 0x00007ffff72c147a in driver::driver::compile_input::h1a790388d99652637Bz () from /usr/lib64/librustc-4e7c5e5c.so
#36 0x00007ffff734b7bc in ?? () from /usr/lib64/librustc-4e7c5e5c.so
#37 0x00007ffff7349735 in ?? () from /usr/lib64/librustc-4e7c5e5c.so
#38 0x00007ffff6a4e108 in ?? () from /usr/lib64/librustc-4e7c5e5c.so
#39 0x00007ffff6a4e003 in ?? () from /usr/lib64/librustc-4e7c5e5c.so
#40 0x00007ffff7bafdc2 in ?? () from /usr/lib64/libnative-4e7c5e5c.so
#41 0x00007ffff669566c in ?? () from /usr/lib64/librustrt-4e7c5e5c.so
#42 0x00007ffff6695656 in rust_try () from /usr/lib64/librustrt-4e7c5e5c.so
#43 0x00007ffff6642d03 in unwind::try::h59906d5b05b381f7uFd () from /usr/lib64/librustrt-4e7c5e5c.so
#44 0x00007ffff6642bbc in task::Task::run::h4be314de5a9e0a0fkLc () from /usr/lib64/librustrt-4e7c5e5c.so
#45 0x00007ffff7bafb87 in ?? () from /usr/lib64/libnative-4e7c5e5c.so
#46 0x00007ffff6644621 in ?? () from /usr/lib64/librustrt-4e7c5e5c.so
#47 0x00007ffff597d294 in start_thread () from /lib64/libpthread.so.0
#48 0x00007ffff631e1ed in clone () from /lib64/libc.so.6

Version

rustc 0.13.0-dev (80e5fe1a5 2014-10-25 09:17:05 +0000)

cc @bkoropoff This seems similar to #17206
cc @nick29581

[nrc]

Minimal test case:

struct Str {
    f: [u8]
}

fn main() {
    let str: Option<&Str> = None;
    str.is_some();
}