thread 'rustc' panicked at 'Box<Any>', C:/bot/slave/beta-dist-rustc-win-64/build/src/libsyntax\diagnostic.rs:190

[frast]

rustc 1.0.0-beta (9854143cb 2015-04-02) (built 2015-04-02)
binary: rustc
commit-hash: 9854143cba679834bc4ef932858cd5303f015a0e
commit-date: 2015-04-02
build-date: 2015-04-02
host: x86_64-pc-windows-gnu
release: 1.0.0-beta

>cargo test
   Compiling maumau v0.0.1 (file:///D:/Frank/wsrust/maumau)
error: internal compiler error: translating unsupported cast: collections::vec::Vec<Card> (cast_other) -> collections::vec::Vec<Card> (cast_other)
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 'Box<Any>', C:/bot/slave/beta-dist-rustc-win-64/build/src/libsyntax\diagnostic.rs:190

stack backtrace:
   1:         0x7120a633 - sys::backtrace::write::h25aa4e11fcc2028f1WC
   2:         0x7121fba1 - rt::unwind::register::h9ce64145fe2dc510hwI
   3:         0x71183620 - rt::unwind::begin_unwind_inner::hf236e20eb0b16c32rtI
   4:           0x754cd9 - diagnostic::SpanHandler::span_bug::h88a5d2017e48721bInB
   5:           0x755315 - diagnostic::Handler::bug::h82c8da3961402202otB
   6:           0xee6a59 - session::Session::bug::hb5ab23038284b253BXq
   7:         0x6366fe85 - trans::common::erase_regions::RegionEraser<'a, 'tcx>.TypeFolder<'tcx>::fold_substs::hbbda23566821fce0twk
   8:         0x63658642 - trans::expr::Dest...std..clone..Clone::clone::h11cda8eb15b4885aNdh
   9:         0x63610295 - trans::cleanup::FunctionContext<'blk, 'tcx>.CleanupMethods<'blk, 'tcx>::pop_and_trans_ast_cleanup_scope::hba39b06ec7f781a4ekK
  10:         0x636111c8 - trans::cleanup::FunctionContext<'blk, 'tcx>.CleanupMethods<'blk, 'tcx>::pop_and_trans_ast_cleanup_scope::hba39b06ec7f781a4ekK
  11:         0x636df257 - trans::base::FindNestedReturn.Visitor<'v>::visit_expr::h39e34e4386a53ebct5s
  12:         0x635fadcb - trans::context::CrateContext<'b, 'tcx>::sess::h1d81b1d9bc057ec9B9l
  13:         0x635f5be4 - trans::context::CrateContext<'b, 'tcx>::stats::h16ae95abc845dd19kkm
  14:         0x636e749c - trans::base::trans_crate::h78838eb055cd54ebuZu
  15:         0x652eccf5 - driver::phase_4_translate_to_llvm::hb6104f3c215dde0caOa
  16:         0x652c2e5a - driver::compile_input::hd172863ffe4dd5a9Qba
  17:         0x65376df3 - run_compiler::ha8dc88b187adc4adV4b
  18:         0x65374bff - run::h4d0e6e374a64009fB4b
  19:         0x65373fda - run::h4d0e6e374a64009fB4b
  20:         0x712591fc - rust_try
  21:         0x712591d9 - rust_try
  22:         0x653742c1 - run::h4d0e6e374a64009fB4b
  23:         0x71213914 - sys::tcp::TcpListener::bind::haf20c04cf24cedd8oVG
  24:     0x7ff8849e13d2 - BaseThreadInitThunk

Could not compile `maumau`.

program:

extern crate rand;
use rand::Rng;

#[allow(dead_code)]
fn main() {
    println!("Hello World!");
}

#[derive(PartialEq, Eq, Clone, Copy)]
pub enum Rank {
    R7,
    R8,
    R9,
    R10,
    B,
    Q,
    K,
    A,
}

#[derive(PartialEq, Eq, Clone, Copy)]
pub enum Suit {
    Clubs,
    Diamonds,
    Hearts,
    Spades,
}

#[derive(PartialEq, Eq, Clone, Copy)]
struct Card(i8);

impl Card {
    pub fn rank(&self) -> Rank {
        Rank::R7
    }

    pub fn suit(&self) -> Suit {
        Suit::Clubs
    }
}

pub type Cards = Vec<Card>;

pub fn shuffled_deck() -> Cards {
    let mut rng = rand::thread_rng();
    let mut cds = Vec::with_capacity(10);
    for _ in 0..10 {
        cds.push(Card((rng.gen::<u8>() % 32) as i8));
    }
    cds as Cards
}

#[cfg(test)]
mod test {
    use super::*;

    #[test]
    fn card_test() {
        let c = shuffled_deck()[0];
        assert!(c.rank() == Rank::R7);
        assert!(c.suit() == Suit::Clubs);
    }
}

[bytwise]

Reduced testcase:

type Cards = Vec<u8>;

fn main() {
    let v: Vec<u8> = Vec::new();
    v as Cards;
}

[pmarcelll]

I can't reproduce it with rustc 1.2.0-nightly (20d23d8e5 2015-06-18).

[alexcrichton]

Agreed, thanks @pmarcelll for the triage!

[pmarcelll]

👍