rustc panicked when I use 'let binding' to 'destructure' an enum

[yykkxk]

I know it is an error to 'destructure an enum with let binding'. But it should be a compile error, not a compiler panic. I find it occurs when an enum has three kinds of structs.(normal struct, unit struct, tuple struct)

I tried this code.

enum Language {
    Chinese(i32),
    Janpanese,
    Other {
          a: i32,
          b: i32,
    }
}

fn main() {
    let c = Language::Chinese(32);
    let Language::Chinese(i) = c;
}

I got this:

Compiling rust-study v0.1.0 (file:///home/ding/project-fedora/rust-study)
error: internal compiler error: unexpected panic
note: the compiler unexpectedly panicked. this is a bug.
note: we would appreciate a bug report: https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.md#bug-reports
note: run with RUST_BACKTRACE=1 for a backtrace
thread 'rustc' panicked at 'assertion failed: (left == right) (left: 2, right: 1)', ../src/librustc/middle/check_match.rs:1051
note: Run with RUST_BACKTRACE=1 for a backtrace.

Meta

rustc 1.9.0-nightly (7b0b80a 2016-03-02)
binary: rustc
commit-hash: 7b0b80a
commit-date: 2016-03-02
host: x86_64-unknown-linux-gnu
release: 1.9.0-nightly

Backtrace:

[...........]$ RUST_BACKTRACE=1 cargo build -v
Compiling ..........
Running rustc book_learn/enum.rs --crate-name gcc --crate-type bin -g --out-dir /home/ding/project-fedora/rust-study/target/debug --emit=dep-info,link -L dependency=/home/ding/project-fedora/rust-study/target/debug -L dependency=/home/ding/project-fedora/rust-study/target/debug/deps
error: internal compiler error: unexpected panic
note: the compiler unexpectedly panicked. this is a bug.
note: we would appreciate a bug report: https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.md#bug-reports
thread 'rustc' panicked at 'assertion failed: (left == right) (left: 2, right: 1)', ../src/librustc/middle/check_match.rs:1051
stack backtrace:
1: 0x7f279cde7420 - sys::backtrace::tracing::imp::write::hafd161163f579c22qhv
2: 0x7f279cdf07cb - panicking::default_handler::$u7b$$u7b$closure$u7d$$u7d$::closure.44622
3: 0x7f279cdf0323 - panicking::default_handler::hf2d947b7574856d7OWz
4: 0x7f279cdb4a9c - sys_common::unwind::begin_unwind_inner::hc47573e10f703d4dJ5t
5: 0x7f279cdb5538 - sys_common::unwind::begin_unwind_fmt::h46e3049686ee3eb0P4t
6: 0x7f279a0a0a68 - middle::check_match::check_irrefutable::hf4f3190a79f4e43992j
7: 0x7f279a071a12 - middle::check_match::check_local::h98b3e55827a94f0230j
8: 0x7f279a071c67 - middle::check_match::check_fn::h611a29c4ed420569T1j
9: 0x7f279a0723d1 - middle::check_match::check_crate::h958664ff10508e28DQi
10: 0x7f279d3181ce - driver::phase_3_run_analysis_passes::$u7b$$u7b$closure$u7d$$u7d$::closure.28569
11: 0x7f279d3150b4 - middle::ty::context::ctxt<'tcx>::create_and_enter::h9120522648527365715
12: 0x7f279d311b9f - driver::phase_3_run_analysis_passes::h6774489415173405543
13: 0x7f279d2e4ed5 - driver::compile_input::hff497ea9e892ddf1Hca
14: 0x7f279d2d2a57 - run_compiler::hd54b7109a035c12b6Oc
15: 0x7f279d2d01d1 - sys_common::unwind::try::try_fn::h12672314472111852986
16: 0x7f279cde4e0b - __rust_try
17: 0x7f279cddd2ed - sys_common::unwind::inner_try::h4ba21e6d9bc82236L2t
18: 0x7f279d2d0a20 - boxed::F.FnBox::call_box::h3704598993629746835
19: 0x7f279cdeed99 - sys::thread::Thread::new::thread_start::hf030860cf63100a98Ty
20: 0x7f2795556609 - start_thread
21: 0x7f279ca60a4c - clone
22: 0x0 -

Could not compile rust-study.

Caused by:
Process didn't exit successfully: rustc book_learn/enum.rs --crate-name gcc --crate-type bin -g --out-dir /home/ding/project-fedora/rust-study/target/debug --emit=dep-info,link -L dependency=/home/ding/project-fedora/rust-study/target/debug -L dependency=/home/ding/project-fedora/rust-study/target/debug/deps (exit code: 101)

[mitaa]

Could you try a newer nightly build? This should be fixed (#31561)

[yykkxk]

You are right. It has been fixed in the lastest nightly build. Thank you.