compiler segfault with deref of *() in asm arg

[kmcallister]

#![feature(asm)]

fn main() {
    let x = ();
    unsafe {
        let p: *const () = &x;
        asm!("" :: "r"(*p));
    }
}

$ rustc -v
rustc 0.11-pre (cee9a83 2014-04-11 15:54:46 -0700)
host: x86_64-unknown-linux-gnu

$ gdb --args rustc foo.rs
(gdb) run
Program received signal SIGSEGV, Segmentation fault.
0x00007ffff6119b99 in llvm::X86TargetLowering::isZExtFree(llvm::SDValue, llvm::EVT) const ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
(gdb) bt
#0  0x00007ffff6119b99 in llvm::X86TargetLowering::isZExtFree(llvm::SDValue, llvm::EVT) const ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#1  0x00007ffff62650fd in (anonymous namespace)::RegsForValue::getCopyToRegs(llvm::SDValue, llvm::SelectionDAG&, llvm::SDLoc, llvm::SDValue&, llvm::SDValue*, llvm::Value const*) const () from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#2  0x00007ffff627d822 in llvm::SelectionDAGBuilder::visitInlineAsm(llvm::ImmutableCallSite) ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#3  0x00007ffff628d5a3 in llvm::SelectionDAGBuilder::visitCall(llvm::CallInst const&) ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#4  0x00007ffff629bc1a in llvm::SelectionDAGBuilder::visit(llvm::Instruction const&) ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#5  0x00007ffff62ad491 in llvm::SelectionDAGISel::SelectBasicBlock(llvm::ilist_iterator<llvm::Instruction const>, llvm::ilist_iterator<llvm::Instruction const>, bool&) () from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#6  0x00007ffff62aeee8 in llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#7  0x00007ffff62b0de5 in llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#8  0x00007ffff6a3d56f in llvm::FPPassManager::runOnFunction(llvm::Function&) ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#9  0x00007ffff6a3d5bb in llvm::FPPassManager::runOnModule(llvm::Module&) ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#10 0x00007ffff6a3d12f in llvm::legacy::PassManagerImpl::run(llvm::Module&) ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#11 0x00007ffff5d4fa5c in LLVMRustWriteOutputFile (Target=0x660720, PMR=0x69a400, M=0x6b7ca0, path=<optimized out>, 
    FileType=llvm::TargetMachine::CGFT_ObjectFile) at /home/keegan/proj/rust/rust/src/rustllvm/PassWrapper.cpp:181
#12 0x00007ffff5bfda5c in back::link::WriteOutputFile::hbd128889f580a8157n0::v0.11.pre ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#13 0x00007ffff5c0396e in back::link::write::run_passes::closure.83721 ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#14 0x00007ffff58d44d5 in util::common::time::h1b088cb92ee0b019kMg::v0.11.pre ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#15 0x00007ffff5bff8a0 in back::link::write::run_passes::hae8f9777a11894c2mq0::v0.11.pre ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#16 0x00007ffff5d10490 in driver::driver::phase_5_run_llvm_passes::closure.90168 ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#17 0x00007ffff58d44d5 in util::common::time::h1b088cb92ee0b019kMg::v0.11.pre ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#18 0x00007ffff5d1031b in driver::driver::phase_5_run_llvm_passes::h10b364552bbe780eQIe::v0.11.pre ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#19 0x00007ffff5d130f2 in driver::driver::compile_input::hef357caacd97acfcPXe::v0.11.pre ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#20 0x00007ffff5d375f5 in run_compiler::ha4e573becdf712cbfvm::v0.11.pre ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#21 0x00007ffff5d4c07c in main_args::closure.92079 ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#22 0x00007ffff5d4aa26 in monitor::closure.91964 () from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#23 0x00007ffff5d462d8 in task::TaskBuilder::try::closure.91739 ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/librustc-4283bb68-0.11-pre.so
#24 0x00007ffff7bbb348 in task::spawn_opts::closure.7852 ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/libnative-83574243-0.11-pre.so
#25 0x00007ffff4b76b03 in rt::task::Task::run::closure.39978 ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/libstd-aad93cea-0.11-pre.so
#26 0x00007ffff4b8213c in rust_try () from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/libstd-aad93cea-0.11-pre.so
#27 0x00007ffff4b76962 in rt::task::Task::run::h6d25268f43c2f945vc8::v0.11.pre ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/libstd-aad93cea-0.11-pre.so
#28 0x00007ffff7bbb1d0 in task::spawn_opts::closure.7825 ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/libnative-83574243-0.11-pre.so
#29 0x00007ffff4b7a24f in rt::thread::thread_start::hceb81ee57b19689fdR8::v0.11.pre ()
   from /home/keegan/proj/rust/rust/x86_64-unknown-linux-gnu/stage2/bin/../lib/libstd-aad93cea-0.11-pre.so
#30 0x00007ffff1f29b50 in start_thread (arg=<optimized out>) at pthread_create.c:304
#31 0x00007ffff47c30ed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#32 0x0000000000000000 in ?? ()

[tamird]

Triage: this segfaults the compiler.

[steveklabnik]

Tagging with ICE. this still segfaults, which isn't technically an ICE, but is arguably worse.

[Ericson2314]

On rustc 1.9.0-nightly (177905703 2016-04-08) getting something similar:

#0  0x00007ffff2c71749 in llvm::X86TargetLowering::isZExtFree(llvm::SDValue, llvm::EVT) const ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#1  0x00007ffff2ee6980 in llvm::RegsForValue::getCopyToRegs(llvm::SDValue, llvm::SelectionDAG&, llvm::SDLoc, llvm::SDValue&, llvm::SDValue*, llvm::Value const*, llvm::ISD::NodeType) const ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#2  0x00007ffff2f02d85 in llvm::SelectionDAGBuilder::visitInlineAsm(llvm::ImmutableCallSite) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#3  0x00007ffff2f1526d in llvm::SelectionDAGBuilder::visitCall(llvm::CallInst const&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#4  0x00007ffff2f2434a in llvm::SelectionDAGBuilder::visit(llvm::Instruction const&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#5  0x00007ffff2f308f1 in llvm::SelectionDAGISel::SelectBasicBlock(llvm::ilist_iterator<llvm::Instruction const>, llvm::ilist_iterator<llvm::Instruction const>, bool&) () from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#6  0x00007ffff2f37618 in llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#7  0x00007ffff2f3934a in llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#8  0x00007ffff2c69d14 in (anonymous namespace)::X86DAGToDAGISel::runOnMachineFunction(llvm::MachineFunction&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#9  0x00007ffff398d007 in llvm::FPPassManager::runOnFunction(llvm::Function&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#10 0x00007ffff398d04b in llvm::FPPassManager::runOnModule(llvm::Module&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#11 0x00007ffff398ebcf in llvm::legacy::PassManagerImpl::run(llvm::Module&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#12 0x00007ffff2500d08 in LLVMRustWriteOutputFile (Target=0x7fffea70ab00, PMR=0x7fffeca1ac40, M=0x7fffecbd0c00, 
    path=0x7fffea455520 "/home/john/Code/git/os/fringe/target/i686-unknown-linux-gnu/debug/fpe-e1ad571a17a8b4d2.0.o", 
    FileType=llvm::TargetMachine::CGFT_ObjectFile)
    at /buildslave/rust-buildbot/slave/nightly-dist-rustc-linux/build/src/rustllvm/PassWrapper.cpp:276
#13 0x00007ffff63fa1e4 in rustc_trans::back::write::write_output_file::hdb50287d746d6d52 ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_trans-18402db3.so
#14 0x00007ffff63fc59b in rustc_trans::back::write::optimize_and_codegen::_$u7b$$u7b$closure$u7d$$u7d$::h40c3c076fb90a91a ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_trans-18402db3.so
#15 0x00007ffff6404107 in rustc_trans::back::write::execute_work_item::h4fb548b629e1a597 ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_trans-18402db3.so
#16 0x00007ffff63fd6d2 in rustc_trans::back::write::run_passes::hb492d8bcd01a6d9e ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_trans-18402db3.so
#17 0x00007ffff7a7d5e8 in rustc_driver::driver::phase_5_run_llvm_passes::h3e9465e211407306 ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_driver-18402db3.so
#18 0x00007ffff7a40451 in rustc_driver::driver::compile_input::h650fe5b01cb8d74d ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_driver-18402db3.so
#19 0x00007ffff7a26435 in rustc_driver::run_compiler::h68d23e0e9b7b247d ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_driver-18402db3.so
#20 0x00007ffff7a23892 in std::sys_common::unwind::try::try_fn::h67fde221a73148bc ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_driver-18402db3.so
#21 0x00007ffff74ada1c in __rust_try () from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/libstd-18402db3.so
#22 0x00007ffff74ad9ae in std::sys_common::unwind::inner_try::h4e97625a08807651 ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/libstd-18402db3.so
#23 0x00007ffff7a240db in _$LT$F$u20$as$u20$std..boxed..FnBox$LT$A$GT$$GT$::call_box::hc8936fa120642c49 ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_driver-18402db3.so
#24 0x00007ffff74bbb45 in std::sys::thread::Thread::new::thread_start::h74af400293164137 ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/libstd-18402db3.so
#25 0x00007fffef10b714 in start_thread () from /nix/store/pv9sza1cf2kpawck7wbwdnhlip5h57lg-glibc-2.23/lib/libpthread.so.0
#26 0x00007ffff711cc5d in clone () from /nix/store/pv9sza1cf2kpawck7wbwdnhlip5h57lg-glibc-2.23/lib/libc.so.6#0  0x00007ffff2c71749 in llvm::X86TargetLowering::isZExtFree(llvm::SDValue, llvm::EVT) const ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#1  0x00007ffff2ee6980 in llvm::RegsForValue::getCopyToRegs(llvm::SDValue, llvm::SelectionDAG&, llvm::SDLoc, llvm::SDValue&, llvm::SDValue*, llvm::Value const*, llvm::ISD::NodeType) const ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#2  0x00007ffff2f02d85 in llvm::SelectionDAGBuilder::visitInlineAsm(llvm::ImmutableCallSite) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#3  0x00007ffff2f1526d in llvm::SelectionDAGBuilder::visitCall(llvm::CallInst const&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#4  0x00007ffff2f2434a in llvm::SelectionDAGBuilder::visit(llvm::Instruction const&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#5  0x00007ffff2f308f1 in llvm::SelectionDAGISel::SelectBasicBlock(llvm::ilist_iterator<llvm::Instruction const>, llvm::ilist_iterator<llvm::Instruction const>, bool&) () from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#6  0x00007ffff2f37618 in llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#7  0x00007ffff2f3934a in llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#8  0x00007ffff2c69d14 in (anonymous namespace)::X86DAGToDAGISel::runOnMachineFunction(llvm::MachineFunction&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#9  0x00007ffff398d007 in llvm::FPPassManager::runOnFunction(llvm::Function&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#10 0x00007ffff398d04b in llvm::FPPassManager::runOnModule(llvm::Module&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#11 0x00007ffff398ebcf in llvm::legacy::PassManagerImpl::run(llvm::Module&) ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_llvm-18402db3.so
#12 0x00007ffff2500d08 in LLVMRustWriteOutputFile (Target=0x7fffea70ab00, PMR=0x7fffeca1ac40, M=0x7fffecbd0c00, 
    path=0x7fffea455520 "/home/john/Code/git/os/fringe/target/i686-unknown-linux-gnu/debug/fpe-e1ad571a17a8b4d2.0.o", 
    FileType=llvm::TargetMachine::CGFT_ObjectFile)
    at /buildslave/rust-buildbot/slave/nightly-dist-rustc-linux/build/src/rustllvm/PassWrapper.cpp:276
#13 0x00007ffff63fa1e4 in rustc_trans::back::write::write_output_file::hdb50287d746d6d52 ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_trans-18402db3.so
#14 0x00007ffff63fc59b in rustc_trans::back::write::optimize_and_codegen::_$u7b$$u7b$closure$u7d$$u7d$::h40c3c076fb90a91a ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_trans-18402db3.so
#15 0x00007ffff6404107 in rustc_trans::back::write::execute_work_item::h4fb548b629e1a597 ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_trans-18402db3.so
#16 0x00007ffff63fd6d2 in rustc_trans::back::write::run_passes::hb492d8bcd01a6d9e ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_trans-18402db3.so
#17 0x00007ffff7a7d5e8 in rustc_driver::driver::phase_5_run_llvm_passes::h3e9465e211407306 ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_driver-18402db3.so
#18 0x00007ffff7a40451 in rustc_driver::driver::compile_input::h650fe5b01cb8d74d ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_driver-18402db3.so
#19 0x00007ffff7a26435 in rustc_driver::run_compiler::h68d23e0e9b7b247d ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_driver-18402db3.so
#20 0x00007ffff7a23892 in std::sys_common::unwind::try::try_fn::h67fde221a73148bc ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_driver-18402db3.so
#21 0x00007ffff74ada1c in __rust_try () from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/libstd-18402db3.so
#22 0x00007ffff74ad9ae in std::sys_common::unwind::inner_try::h4e97625a08807651 ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/libstd-18402db3.so
#23 0x00007ffff7a240db in _$LT$F$u20$as$u20$std..boxed..FnBox$LT$A$GT$$GT$::call_box::hc8936fa120642c49 ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/librustc_driver-18402db3.so
#24 0x00007ffff74bbb45 in std::sys::thread::Thread::new::thread_start::h74af400293164137 ()
   from /nix/store/npk25f8bbr4n666i2kik2w593nbz6vwx-rustc-nightly-2016-04-09/lib/libstd-18402db3.so
#25 0x00007fffef10b714 in start_thread () from /nix/store/pv9sza1cf2kpawck7wbwdnhlip5h57lg-glibc-2.23/lib/libpthread.so.0
#26 0x00007ffff711cc5d in clone () from /nix/store/pv9sza1cf2kpawck7wbwdnhlip5h57lg-glibc-2.23/lib/libc.so.6

probably also asm!() related.

[Mark-Simulacrum]

I suspect, though am uncertain, that this now breaks within LLVM. It's possible that we run code in between, though, so I can't be certain. I'm also not sure what specifically is breaking, but the exit code is 1.

Last few lines of time-passes:

time: 0.000; rss: 91MB	MIR optimisations
  time: 0.000; rss: 91MB	write metadata
  time: 0.000; rss: 91MB	translation item collection
  time: 0.000; rss: 91MB	codegen unit partitioning
  time: 0.000; rss: 112MB	internalize symbols
time: 0.054; rss: 112MB	translation
time: 0.000; rss: 112MB	assert dep graph
time: 0.000; rss: 112MB	serialize dep graph
  time: 0.000; rss: 112MB	llvm function passes [0]
  time: 0.000; rss: 112MB	llvm module passes [0]

[steveklabnik]

Triage: not aware of changes

[pnkfelix]

ICE is dependent on feature(asm) (cc #29722), which is not on the 2019 roadmap. Marking as P-medium until we get an overall plan for asm in Rust. (Although the fact that this can cause rustc itself to segfault, presumably via a problem internal to LLVM, does lead me to wonder if I should up the priority to P-high anyway.)