Roman numeral plugin example fails to run

[dtwood]

The roman numeral demo plugin compiles successfully, but fails with an ICE when run (the same as #26488).

rustc --version
rustc 1.3.0-nightly (69ca01256 2015-07-23)

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
Could not compile `hello_world`.

Caused by:
  Process didn't exit successfully: `rustc src/main.rs --crate-name hello_world --crate-type bin -g --out-dir /Users/david/Devel/rust/target/debug --emit=dep-info,link -L dependency=/Users/david/Devel/rust/target/debug -L dependency=/Users/david/Devel/rust/target/debug/deps --extern factorial=/Users/david/Devel/rust/target/debug/deps/libfactorial-9882d961a0581a0c.dylib --extern chrono=/Users/david/Devel/rust/target/debug/deps/libchrono-56e1e2f8a2c2ce0f.rlib` (exit code: 101)
st/target/debug/deps/libchrono-56e1e2f8a2c2ce0f.rlib`
       Fresh chrono v0.2.15
thread 'rustc' panicked at 'index out of bounds: the len is 60 but the index is 66', ../src/libcollections/vec.rs:1246

stack backtrace:
   1:        0x105349485 - sys::backtrace::write::hbce7e265eb321480bus
   2:        0x1053524ee - panicking::on_panic::hd723a4eed80dc3f1NUw
   3:        0x10530bf82 - rt::unwind::begin_unwind_inner::hba49c6e78082e98fYCw
   4:        0x10530ce2c - rt::unwind::begin_unwind_fmt::h9873384d3a1a818e4Bw
   5:        0x10535206c - rust_begin_unwind
   6:        0x1053a81a5 - panicking::panic_fmt::h4ce2c934001461b3PgC
   7:        0x1053a28e5 - panicking::panic_bounds_check::h5bd94edbff5d1337VfC
   8:        0x10a346a45 - parse::token::get_name::hc25bfcba291047ab0jT
   9:        0x10a34c8f8 - ast::Name.fmt..Display::fmt::h9df3ebcee2b7357bsSb
  10:        0x10cc4c3f2 - fmt::write::hf3476932417648edbfO
  11:        0x10cb7ddbb - rt::unwind::begin_unwind_fmt::h9873384d3a1a818e4Bw
  12:        0x101c3cc80 - expand_rn::h25af918a6623e675saa
  13:        0x109d8265e - ext::base::F.TTMacroExpander::expand::h8387169028212889737
  14:        0x102d54863 - ext::expand::expand_expr::closure.65736
  15:        0x102d4fce0 - ext::expand::expand_expr::h99e8da60288015c7Qeb
  16:        0x102d5878a - fold::noop_fold_expr::h12274104263851486159
  17:        0x102d4fece - ext::expand::expand_expr::closure.65736
  18:        0x102d4fce0 - ext::expand::expand_expr::h99e8da60288015c7Qeb
  19:        0x102d59ee2 - fold::noop_fold_expr::h12274104263851486159
  20:        0x102d4fece - ext::expand::expand_expr::closure.65736
  21:        0x102d4fce0 - ext::expand::expand_expr::h99e8da60288015c7Qeb
  22:        0x102d58dab - fold::noop_fold_expr::h12274104263851486159
  23:        0x102d4fece - ext::expand::expand_expr::closure.65736
  24:        0x102d4fce0 - ext::expand::expand_expr::h99e8da60288015c7Qeb
  25:        0x102d59323 - fold::noop_fold_expr::h12274104263851486159
  26:        0x102d4fece - ext::expand::expand_expr::closure.65736
  27:        0x102d4fce0 - ext::expand::expand_expr::h99e8da60288015c7Qeb
  28:        0x102d9d000 - ext::expand::expand_block_elts::closure.66444
  29:        0x102d62369 - ext::expand::expand_block_elts::hdd4860a523c2af11x0b
  30:        0x102d9cb42 - ext::expand::expand_block::h6f55c6087a5fa9a0SZb
  31:        0x102d598b1 - fold::noop_fold_expr::h12274104263851486159
  32:        0x102d4fece - ext::expand::expand_expr::closure.65736
  33:        0x102d4fce0 - ext::expand::expand_expr::h99e8da60288015c7Qeb
  34:        0x102d96ed1 - fold::noop_fold_stmt::h10788056147892267108
  35:        0x102d77b90 - ext::expand::expand_stmt::h08fa462260688915BPb
  36:        0x102d7aaec - iter::FlatMap<I, U, F>.Iterator::next::h2819660546420465906
  37:        0x102d7a4a7 - util::small_vector::SmallVector<T>.FromIterator<T>::from_iter::h13187313789686060428
  38:        0x102d79167 - ext::expand::expand_stmt::h08fa462260688915BPb
  39:        0x102d9df33 - ext::expand::expand_block_elts::closure.66450
  40:        0x102d9dc65 - iter::FlatMap<I, U, F>.Iterator::next::h7643140614824393032
  41:        0x102d9d324 - vec::Vec<T>.FromIterator<T>::from_iter::h732420624926570779
  42:        0x102d9cf17 - ext::expand::expand_block_elts::closure.66444
  43:        0x102d62369 - ext::expand::expand_block_elts::hdd4860a523c2af11x0b
  44:        0x102d9cb42 - ext::expand::expand_block::h6f55c6087a5fa9a0SZb
  45:        0x102d61e93 - ext::expand::expand_and_rename_fn_decl_and_block::h48826170e337e771Wtc
  46:        0x102d68dd6 - ext::expand::expand_item_underscore::h35b61265f1e6e32a1Db
  47:        0x102dbe7a7 - fold::noop_fold_item_simple::h15338532747737711936
  48:        0x102dbe306 - fold::noop_fold_item::h4339851499862307845
  49:        0x102d66bb7 - ext::expand::expand_annotatable::ha45359526cbf62faTac
  50:        0x102d624f9 - ext::expand::expand_item::h7d12f4c897ccb936qDb
  51:        0x102d6e8e5 - iter::FlatMap<I, U, F>.Iterator::next::h9898030771278316288
  52:        0x102d6e3bc - vec::Vec<T>.FromIterator<T>::from_iter::h13205230158317958734
  53:        0x102d6e0b7 - fold::noop_fold_mod::h15770947105538165412
  54:        0x102d69650 - ext::expand::expand_item_underscore::h35b61265f1e6e32a1Db
  55:        0x102dbe7a7 - fold::noop_fold_item_simple::h15338532747737711936
  56:        0x102dbe306 - fold::noop_fold_item::h4339851499862307845
  57:        0x102d677ed - ext::expand::expand_annotatable::ha45359526cbf62faTac
  58:        0x102d624f9 - ext::expand::expand_item::h7d12f4c897ccb936qDb
  59:        0x102dc63fc - ext::expand::expand_crate::he66664571162d53arCc
  60:        0x10180c960 - driver::phase_2_configure_and_expand::closure.22185
  61:        0x1017c15c0 - driver::phase_2_configure_and_expand::h9663d9fc8460a0b7ita
  62:        0x1017b1b08 - driver::compile_input::h88e989740af3db2aTba
  63:        0x1018948ab - run_compiler::he6382510493c3ff3A7b
  64:        0x101892120 - boxed::F.FnBox<A>::call_box::h16554067582215296081
  65:        0x101891997 - rt::unwind::try::try_fn::h9037081342499356393
  66:        0x105351f9f - __rust_try_inner
  67:        0x105351fda - __rust_try
  68:        0x10533ba65 - rt::unwind::try::inner_try::h1e2d97fb62ce1595Ryw
  69:        0x101891bd9 - boxed::F.FnBox<A>::call_box::h15046611992369909973
  70:        0x105350efd - sys::thread::Thread::new::thread_start::h2b5c9a2728ae8fd5RWv
  71:     0x7fff8df83267 - _pthread_body
  72:     0x7fff8df831e4 - _pthread_start

[dtwood]

Minimal example:

> main
  > Cargo.toml
  > src
    > plugin
      > Cargo.toml
      > src
        > lib.rs
    > lib.rs

main/src/lib.rs:

#![feature(plugin)]
#![plugin(factorial)]

fn main() {
    println!(rn!(I));
}

main/src/plugin/src/lib.rs

#![crate_type="dylib"]
#![feature(plugin_registrar, rustc_private)]

extern crate syntax;
extern crate rustc;

use syntax::codemap::Span;
use syntax::parse::token;
use syntax::ast::{TokenTree, TtToken};
use syntax::ext::base::{ExtCtxt, MacResult};
use rustc::plugin::Registry;

fn expand_rn(_: &mut ExtCtxt, _: Span, args: &[TokenTree])
        -> Box<MacResult + 'static> {
    let _ = match args[0] {
        TtToken(_, token::Ident(s, _)) => panic!("{}", s),
        _ => {
            unimplemented!();
        }
    };
    unimplemented!();
}

#[plugin_registrar]
pub fn plugin_registrar(reg: &mut Registry) {
    reg.register_macro("rn", expand_rn);
}

[Munksgaard]

I'm not getting an error with rustc 1.3.0-dev (7276d8b 2015-07-25)

[dtwood]

Still broken here I'm afraid:
rustc --version rustc 1.3.0-nightly (922aef035 2015-07-27)
uname -a Darwin dtw-laptop.local 14.4.0 Darwin Kernel Version 14.4.0: Thu May 28 11:35:04 PDT 2015; root:xnu-2782.30.5~1/RELEASE_X86_64 x86_64

[Munksgaard]

Here's what I did:

plugin.rs:

#![crate_type="dylib"]
#![feature(plugin_registrar, rustc_private)]
#![feature(slice_patterns)]

extern crate syntax;
extern crate rustc;

use syntax::codemap::Span;
use syntax::parse::token;
use syntax::ast::{TokenTree, TtToken};
use syntax::ext::base::{ExtCtxt, MacResult, DummyResult, MacEager};
use syntax::ext::build::AstBuilder;  // trait for expr_usize
use rustc::plugin::Registry;

fn expand_rn(cx: &mut ExtCtxt, sp: Span, args: &[TokenTree])
        -> Box<MacResult + 'static> {

    static NUMERALS: &'static [(&'static str, u32)] = &[
        ("M", 1000), ("CM", 900), ("D", 500), ("CD", 400),
        ("C",  100), ("XC",  90), ("L",  50), ("XL",  40),
        ("X",   10), ("IX",   9), ("V",   5), ("IV",   4),
        ("I",    1)];

    let text = match args {
        [TtToken(_, token::Ident(s, _))] => token::get_ident(s).to_string(),
        _ => {
            cx.span_err(sp, "argument should be a single identifier");
            return DummyResult::any(sp);
        }
    };

    let mut text = &*text;
    let mut total = 0;
    while !text.is_empty() {
        match NUMERALS.iter().find(|&&(rn, _)| text.starts_with(rn)) {
            Some(&(rn, val)) => {
                total += val;
                text = &text[rn.len()..];
            }
            None => {
                cx.span_err(sp, "invalid Roman numeral");
                return DummyResult::any(sp);
            }
        }
    }

    MacEager::expr(cx.expr_u32(sp, total))
}

#[plugin_registrar]
pub fn plugin_registrar(reg: &mut Registry) {
    reg.register_macro("rn", expand_rn);
}

main.rs:

#![feature(plugin)]
#![plugin(plugin)]

fn main() {
    println!(rn!(I));
}

 $ rustc plugin.rs
 $ rustc -L . main.rs
 $ ./main
1

Does that work for you?

I cannot compile main.rs with your minimal example above: It explicitly panics at I.

rustc 1.3.0-dev (8988043da 2015-07-27)

[dtwood]

That doesn't work for me either - I've copied the source you plug above, then rustc plugin.rs succeeds, and gives me libplugin.dylib. rustc -L . main.rs then fails with the following:

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 'index out of bounds: the len is 60 but the index is 65', ../src/libcollections/vec.rs:1246

stack backtrace:
   1:        0x11070c5a5 - sys::backtrace::write::h8d57f899e3fda16elus
   2:        0x11071560e - panicking::on_panic::h5ba36379bfe7cb23XUw
   3:        0x1106cf062 - rt::unwind::begin_unwind_inner::hfdefe03d89c9e15c8Cw
   4:        0x1106cff0c - rt::unwind::begin_unwind_fmt::h4abe28056f41fed5eCw
   5:        0x11071518c - rust_begin_unwind
   6:        0x11076b2f5 - panicking::panic_fmt::h13125e855ad0c512EhC
   7:        0x110765a35 - panicking::panic_bounds_check::h930022a157a2365dKgC
   8:        0x1157d65f7 - util::interner::StrInterner::get::hd168b7b16d7f039aFpa
   9:        0x110be2aa4 - parse::token::get_name::hd9e2929ac0706451apT
  10:        0x110be29d8 - parse::token::get_ident::h8eabd2f158c72c5frpT
  11:        0x110bdeeb3 - expand_rn::h7069071bf5512a5esaa
  12:        0x11521066e - ext::base::F.TTMacroExpander::expand::h13800486614208293857
  13:        0x10e115fcd - ext::expand::expand_expr::closure.66042
  14:        0x10e1103da - ext::expand::expand_expr::h10d1ec6bb3acc3e4rlb
  15:        0x10e0bf88b - ext::base::get_exprs_from_tts::h3230de70dec5bb6fTC5
  16:        0x10e0b848c - ext::concat::expand_syntax_ext::h6d30518a25606a73bi7
  17:        0x10e0bcc0e - ext::base::F.TTMacroExpander::expand::h17916794981785300046
  18:        0x10e115fcd - ext::expand::expand_expr::closure.66042
  19:        0x10e1103da - ext::expand::expand_expr::h10d1ec6bb3acc3e4rlb
  20:        0x10e1b41d8 - ext::format::expand_preparsed_format_args::h39749fc855abdc45vGd
  21:        0x10e0b5f57 - ext::format::expand_format_args::h2034aa489443eeeaIFd
  22:        0x10e0b640e - ext::base::F.TTMacroExpander::expand::h1414252957907639972
  23:        0x10e115fcd - ext::expand::expand_expr::closure.66042
  24:        0x10e1103da - ext::expand::expand_expr::h10d1ec6bb3acc3e4rlb
  25:        0x10e11abcf - fold::noop_fold_expr::h8234447633789036141
  26:        0x10e1105f3 - ext::expand::expand_expr::closure.66042
  27:        0x10e1103da - ext::expand::expand_expr::h10d1ec6bb3acc3e4rlb
  28:        0x10e158fc1 - fold::noop_fold_stmt::h6333715652680442577
  29:        0x10e139d30 - ext::expand::expand_stmt::h8c4bd9703af6a2f7b4b
  30:        0x10e13cc8c - iter::FlatMap<I, U, F>.Iterator::next::h10170223740143956055
  31:        0x10e13c647 - util::small_vector::SmallVector<T>.FromIterator<T>::from_iter::h3322216669002410848
  32:        0x10e13b307 - ext::expand::expand_stmt::h8c4bd9703af6a2f7b4b
  33:        0x10e13cc8c - iter::FlatMap<I, U, F>.Iterator::next::h10170223740143956055
  34:        0x10e13c647 - util::small_vector::SmallVector<T>.FromIterator<T>::from_iter::h3322216669002410848
  35:        0x10e13b307 - ext::expand::expand_stmt::h8c4bd9703af6a2f7b4b
  36:        0x10e15ffe3 - ext::expand::expand_block_elts::closure.66799
  37:        0x10e15fd15 - iter::FlatMap<I, U, F>.Iterator::next::h12880663052903539887
  38:        0x10e15f3d4 - vec::Vec<T>.FromIterator<T>::from_iter::h11897925576472944830
  39:        0x10e15efc7 - ext::expand::expand_block_elts::closure.66792
  40:        0x10e124529 - ext::expand::expand_block_elts::h57e4fa0ef3fb82095ec
  41:        0x10e15ebf2 - ext::expand::expand_block::hebf31e0d54524c16qec
  42:        0x10e124053 - ext::expand::expand_and_rename_fn_decl_and_block::h9735bb96b0f3ef77uIc
  43:        0x10e12af97 - ext::expand::expand_item_underscore::hf55f46424c3923c8BSb
  44:        0x10e1806e7 - fold::noop_fold_item_simple::h13360826160893592273
  45:        0x10e180246 - fold::noop_fold_item::h6178621647060960707
  46:        0x10e128d77 - ext::expand::expand_annotatable::h196830a9bb0064b9rpc
  47:        0x10e1246b9 - ext::expand::expand_item::h20b8951f3ce4e5750Rb
  48:        0x10e130a95 - iter::FlatMap<I, U, F>.Iterator::next::h16067873143848592029
  49:        0x10e13056c - vec::Vec<T>.FromIterator<T>::from_iter::h5969725813415914631
  50:        0x10e130267 - fold::noop_fold_mod::h15221366836033915591
  51:        0x10e12b8d6 - ext::expand::expand_item_underscore::hf55f46424c3923c8BSb
  52:        0x10e1806e7 - fold::noop_fold_item_simple::h13360826160893592273
  53:        0x10e180246 - fold::noop_fold_item::h6178621647060960707
  54:        0x10e1299ad - ext::expand::expand_annotatable::h196830a9bb0064b9rpc
  55:        0x10e1246b9 - ext::expand::expand_item::h20b8951f3ce4e5750Rb
  56:        0x10e18837c - ext::expand::expand_crate::h3f3f15780cfbd68bhRc
  57:        0x10cbb3a70 - driver::phase_2_configure_and_expand::closure.22339
  58:        0x10cb68430 - driver::phase_2_configure_and_expand::h39dfa417ce3247ddita
  59:        0x10cb58978 - driver::compile_input::h87a640b6a6c7679fTba
  60:        0x10cc3bb4b - run_compiler::h1988d61cd748f5f6A7b
  61:        0x10cc393c0 - boxed::F.FnBox<A>::call_box::h8812244964073324717
  62:        0x10cc38c37 - rt::unwind::try::try_fn::h15965772982377226605
  63:        0x1107150bf - __rust_try_inner
  64:        0x1107150fa - __rust_try
  65:        0x1106feb45 - rt::unwind::try::inner_try::h211b654f88b1ec3f1yw
  66:        0x10cc38e79 - boxed::F.FnBox<A>::call_box::h6462970046057749915
  67:        0x11071401d - sys::thread::Thread::new::thread_start::h9dddbcf4515946ba1Wv
  68:     0x7fff904dc267 - _pthread_body
  69:     0x7fff904dc1e4 - _pthread_start

[dtwood]

Just got the nightly (so both 8b83557) working on my linux install, and it's running fine. So it appears to be an OS X only issue.

[Munksgaard]

I guess that would explain something. I forgot to mention that I'm on linux:

$ uname -a
Linux turing 4.0.0-rc3 #15 SMP Mon Mar 9 16:42:51 CET 2015 x86_64 Intel(R) Core(TM) i7-4600U CPU @ 2.10GHz GenuineIntel GNU/Linux

[russellmcc]

I actually am reproducing this issue still on homebrew (the Mac OS X package manager) nightlies, but not when I build myself from source. Very strange.

rustc 1.3.0-nightly (83b9deaf2 2015-08-01)

[regexident]

Working fine on OS X with rustc 1.13.0-nightly. Should this be closed?

[dtwood]

Yup, this now seems to be working with the latest version of rust from homebrew, so closing