$ RUST_LOG=rustc=1,::rt::backtrace rustc frscript.rs
rust: task failed at 'assertion failed: rp.is_none()', /build/rust/src/rust-0.7/src/librustc/middle/typeck/collect.rs:1040
/usr/lib/librustrt.so(_ZN9rust_task13begin_failureEPKcS1_m+0x4b)[0x7f6564c2ebcb]
/usr/lib/librustrt.so(+0x2b081)[0x7f6564c40081]
/usr/lib/librustrt.so(upcall_fail+0x198)[0x7f6564c30b78]
/usr/lib/libstd-6c65cf4b443341b1-0.7.so(_ZN3sys13begin_unwind_16_89e154cd09156717_0$x2e7E+0x3cc)[0x7f656669a1ec]
/usr/lib/libstd-6c65cf4b443341b1-0.7.so(+0xfde12)[0x7f6566699e12]
/usr/lib/libstd-6c65cf4b443341b1-0.7.so(+0xfdd41)[0x7f6566699d41]
/usr/lib/libstd-6c65cf4b443341b1-0.7.so(+0xfddcc)[0x7f6566699dcc]
/usr/lib/libstd-6c65cf4b443341b1-0.7.so(+0xfdd41)[0x7f6566699d41]
/usr/lib/libstd-6c65cf4b443341b1-0.7.so(_ZN3sys14__extensions__10meth_100689fail_with17_d96679812a86c3677_0$x2e7E+0x7b)[0x7f656660425b]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(_ZN6middle6typeck7collect10ty_of_item17_beaa83da2b58af297_0$x2e7E+0x6c9)[0x7f6565354ae9]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(_ZN6middle6typeck7collect7convert17_f4b5d9644b94cdce7_0$x2e7E+0x323)[0x7f6565352a53]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(+0x4ee66a)[0x7f656535266a]
/usr/lib/libsyntax-64629f7f0c6a9bc-0.7.so(_ZN5visit17mk_simple_visitor6v_item16_95d273f237092797_0$x2e7E+0x4c)[0x7f6565bebcbc]
/usr/lib/libsyntax-64629f7f0c6a9bc-0.7.so(+0xf81a8)[0x7f6565bee1a8]
/usr/lib/libsyntax-64629f7f0c6a9bc-0.7.so(+0xcba15)[0x7f6565bc1a15]
/usr/lib/libsyntax-64629f7f0c6a9bc-0.7.so(_ZN5visit17mk_simple_visitor5v_mod17_f6d0e148e46248147_0$x2e7E+0xc1)[0x7f6565beb7f1]
/usr/lib/libsyntax-64629f7f0c6a9bc-0.7.so(+0xf7e64)[0x7f6565bede64]
/usr/lib/libsyntax-64629f7f0c6a9bc-0.7.so(+0xcc4bd)[0x7f6565bc24bd]
/usr/lib/libsyntax-64629f7f0c6a9bc-0.7.so(_ZN5visit17mk_simple_visitor6v_item16_95d273f237092797_0$x2e7E+0x69)[0x7f6565bebcd9]
/usr/lib/libsyntax-64629f7f0c6a9bc-0.7.so(+0xf81a8)[0x7f6565bee1a8]
/usr/lib/libsyntax-64629f7f0c6a9bc-0.7.so(+0xcba15)[0x7f6565bc1a15]
/usr/lib/libsyntax-64629f7f0c6a9bc-0.7.so(_ZN5visit17mk_simple_visitor5v_mod17_f6d0e148e46248147_0$x2e7E+0xc1)[0x7f6565beb7f1]
/usr/lib/libsyntax-64629f7f0c6a9bc-0.7.so(+0xf7e64)[0x7f6565bede64]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(+0x26ffef)[0x7f65650d3fef]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(_ZN6middle6typeck7collect18collect_item_types16_dc19ff6aa918bfe7_0$x2e7E+0x610)[0x7f6565351d40]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(+0x52a960)[0x7f656538e960]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(_ZN6middle6typeck11check_crate16_a8160c649eefde67_0$x2e7E+0x18a)[0x7f656538e3aa]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(_ZN6driver6driver12compile_rest17_9d43bfd27f75116d7_0$x2e7E+0x11b6)[0x7f656560e586]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(+0x7df6f4)[0x7f65656436f4]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(_ZN6driver6driver12compile_upto15_6fdb4f7b58f7cc7_0$x2e7E+0x13c)[0x7f6565611eac]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(_ZN6driver6driver13compile_input17_2dfa2321fefd7a847_0$x2e7E+0xd5)[0x7f6565612245]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(_ZN12run_compiler17_7449a6c8ce5854637_0$x2e7E+0x1b13)[0x7f6565631633]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(+0x7df41e)[0x7f656564341e]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(+0x7dcec7)[0x7f6565640ec7]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(+0x7d47db)[0x7f65656387db]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(+0x7df6f4)[0x7f65656436f4]
/usr/lib/libstd-6c65cf4b443341b1-0.7.so(+0xd0ca1)[0x7f656666cca1]
/usr/lib/libstd-6c65cf4b443341b1-0.7.so(+0x1470ac)[0x7f65666e30ac]
/usr/lib/librustrt.so(_Z18task_start_wrapperP10spawn_args+0x22)[0x7f6564c2f502]
error: internal compiler error: unexpected failure
note: the compiler hit an unexpected failure path. this is a bug
note: try running with RUST_LOG=rustc=1,::rt::backtrace to get further details and report the results to github.com/mozilla/rust/issues
rust: task failed at 'explicit failure', /build/rust/src/rust-0.7/src/librustc/rustc.rs:354
/usr/lib/librustrt.so(_ZN9rust_task13begin_failureEPKcS1_m+0x4b)[0x7f6564c2ebcb]
/usr/lib/librustrt.so(+0x2b081)[0x7f6564c40081]
/usr/lib/librustrt.so(upcall_fail+0x198)[0x7f6564c30b78]
/usr/lib/libstd-6c65cf4b443341b1-0.7.so(_ZN3sys13begin_unwind_16_89e154cd09156717_0$x2e7E+0x3cc)[0x7f656669a1ec]
/usr/lib/libstd-6c65cf4b443341b1-0.7.so(+0xfe372)[0x7f656669a372]
/usr/lib/libstd-6c65cf4b443341b1-0.7.so(+0xfdd41)[0x7f6566699d41]
/usr/lib/libstd-6c65cf4b443341b1-0.7.so(+0xfe32c)[0x7f656669a32c]
/usr/lib/libstd-6c65cf4b443341b1-0.7.so(+0xfdd41)[0x7f6566699d41]
/usr/lib/libstd-6c65cf4b443341b1-0.7.so(+0x7d0a4)[0x7f65666190a4]
/usr/lib/libstd-6c65cf4b443341b1-0.7.so(+0x1470ac)[0x7f65666e30ac]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(_ZN7monitor17_bd33c0a4efdb3aac7_0$x2e7E+0x2295)[0x7f6565634515]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(+0x7df6f4)[0x7f65656436f4]
/usr/lib/librustc-d3cb8c2ccd84a7a7-0.7.so(_ZN4main15_f3d16eaf7d57387_0$x2e7E+0x87)[0x7f6565643347]
/usr/lib/librustrt.so(_Z18task_start_wrapperP10spawn_args+0x22)[0x7f6564c2f502]
rust: domain main @0xf1ad70 root task failed