Certain unicode character combinations make the compiler angry

[AngryLawyer]

So, I have the following

mod tokenizer {

    #[test]
    fn test_tokenize_one() {
        //Numbers
        let string = ~"1";
        let string = ~"321";

        //Strings
        let string = ~"'This is a string'";

        //Operators
        let string = ~"⍒";
        let string = ~"÷";

        //Comments
        let string = ~"⍝";
        let string = ~"⍝ lol";

        //Function definition
        let string = ~"∇Function";

        //Close function
        let string = ~"∇";

        //Endlines
        let string = ~"\n";

        //Variables
        let string = ~"⍙var";
        let string = ~"∆var";
        let string = ~"var";
    }
}

And for some reason, on both my OSX build of Incoming, and my on my Ubuntu build of it, I get an error:

rust: task failed at 'Assertion bpos == mbc.pos || bpos.to_uint() >= mbc.pos.to_uint() + mbc.bytes failed', /home/tony/Projects/rust/src/libsyntax/codemap.rs:500

When I start using the variables (such as sticking Print statements after each definition of it) it compiles fine. Taking out the weird APL symbols that my interpreter is going to be testing also fixes it.

Is there an issue with having too many unused instances of a variable? Or with trouble with (super obscure) Unicode glyphs?

[jdm]

The backtrace from rust_task_fail would be informative.

[AngryLawyer]

Of course. I assume it's all the gumpf that comes out of RUST_LOG=rustc=1,::rt::backtrace

Here we go:

tony@tony-ubuntu:~/Projects/rust-apl$ RUST_LOG=rustc=1,::rt::backtrace rustc src/rust-apl.rc -o bin/test --test
src/tests.rs:7:9: 7:17 warning: unused variable: `string`
src/tests.rs:7         let string = ~"1";
                        ^~~~~~~~
src/tests.rs:8:12: 8:20 warning: unused variable: `string`
src/tests.rs:8         let string = ~"321";
                           ^~~~~~~~
src/tests.rs:11:12: 11:20 warning: unused variable: `string`
src/tests.rs:11         let string = ~"'This is a string'";
                            ^~~~~~~~
src/tests.rs:14:12: 14:20 warning: unused variable: `string`
src/tests.rs:14         let string = ~"⍒";
                            ^~~~~~~~
src/tests.rs:15:12: 15:20 warning: unused variable: `string`
src/tests.rs:15         let string = ~"÷";
                            ^~~~~~~~
rust: task failed at 'Assertion bpos == mbc.pos || bpos.to_uint() >= mbc.pos.to_uint() + mbc.bytes failed', /home/tony/Projects/rust/src/libsyntax/codemap.rs:500
/usr/local/bin/../lib/librustrt.so(_ZN9rust_task13begin_failureEPKcS1_m+0x4b)[0x7f0ba053ef9b]
/usr/local/bin/../lib/librustrt.so(+0x2b109)[0x7f0ba0550109]
/usr/local/bin/../lib/librustrt.so(upcall_fail+0x188)[0x7f0ba0540d78]
/usr/local/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0xf8a5b)[0x7f0ba2081a5b]
/usr/local/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x413fe)[0x7f0ba1fca3fe]
/usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so(_ZN7codemap14__extensions__9meth_925124bytepos_to_local_charpos17_2ef2f680debabbad3_06E+0x3de)[0x7f0ba155149e]
/usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so(_ZN7codemap14__extensions__9meth_911110lookup_pos17_fa9d322f72fd53163_06E+0x7b)[0x7f0ba154f55b]
/usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so(_ZN7codemap14__extensions__9meth_911319lookup_char_pos_adj16_49afbe1de9c0f593_06E+0x54)[0x7f0ba154fc64]
/usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so(_ZN7codemap14__extensions__9meth_851411span_to_str17_cac44644182bf88b3_06E+0xe6)[0x7f0ba154c5b6]
/usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so(_ZN10diagnostic4emit16_d2f47fc894c93203_06E+0xe5)[0x7f0ba1547fb5]
/usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so(+0x2811b8)[0x7f0ba17661b8]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8ea193)[0x7f0ba106b193]
/usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so(_ZN10diagnostic14__extensions__9meth_81704emit16_d2f47fc894c93203_06E+0x4d)[0x7f0ba15463bd]
/usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so(_ZN10diagnostic14__extensions__9meth_81209span_warn14_2f48a8a4d33843_06E+0x10e)[0x7f0ba154547e]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x6dc93e)[0x7f0ba0e5d93e]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6middle8liveness14__extensions__10meth_6921217warn_about_unused17_eaa396e49e4084683_06E+0xe4)[0x7f0ba0e5a174]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x6dc5b6)[0x7f0ba0e5d5b6]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x6d03dc)[0x7f0ba0e513dc]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x701f2a)[0x7f0ba0e82f2a]
/usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so(_ZN8ast_util8walk_pat17_b8bf7b22f55e85f03_06E+0x45)[0x7f0ba1598205]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6middle8liveness14__extensions__10meth_6883112pat_bindings16_ddf8809261f68fb3_06E+0xaa)[0x7f0ba0e5129a]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x6cc99c)[0x7f0ba0e4d99c]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x1f9226)[0x7f0ba097a226]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x1f7ce1)[0x7f0ba0978ce1]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x1eaafa)[0x7f0ba096bafa]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x6bd832)[0x7f0ba0e3e832]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x1f6388)[0x7f0ba0977388]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x1f5c24)[0x7f0ba0976c24]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x1f63f9)[0x7f0ba09773f9]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x1f5c24)[0x7f0ba0976c24]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x1f63f9)[0x7f0ba09773f9]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x1f5c24)[0x7f0ba0976c24]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6middle8liveness11check_crate17_1628ef44bfc587c93_06E+0x40e)[0x7f0ba0e3448e]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8a92f9)[0x7f0ba102a2f9]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8a7f38)[0x7f0ba1028f38]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6driver6driver12compile_rest17_ae80a5494db8f5f03_06E+0x1d98)[0x7f0ba10262e8]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8ec184)[0x7f0ba106d184]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6driver6driver12compile_upto16_3511ccef3fbc8173_06E+0x107)[0x7f0ba102a677]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6driver6driver13compile_input17_da16f137dd9fced53_06E+0xb9)[0x7f0ba102aa79]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN12run_compiler16_a31e58461d354de3_06E+0x223a)[0x7f0ba1058d2a]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8e90e1)[0x7f0ba106a0e1]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8e774e)[0x7f0ba106874e]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8ec184)[0x7f0ba106d184]
/usr/local/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0xc3e5f)[0x7f0ba204ce5f]
/usr/local/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x129f60)[0x7f0ba20b2f60]
/usr/local/bin/../lib/librustrt.so(_Z18task_start_wrapperP10spawn_args+0x24)[0x7f0ba053f7e4]
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', /home/tony/Projects/rust/src/librustc/rustc.rc:364
/usr/local/bin/../lib/librustrt.so(_ZN9rust_task13begin_failureEPKcS1_m+0x4b)[0x7f0ba053ef9b]
/usr/local/bin/../lib/librustrt.so(+0x2b109)[0x7f0ba0550109]
/usr/local/bin/../lib/librustrt.so(upcall_fail+0x188)[0x7f0ba0540d78]
/usr/local/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0xf8a5b)[0x7f0ba2081a5b]
/usr/local/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0xf8a02)[0x7f0ba2081a02]
/usr/local/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(_ZN3sys12begin_unwind17_7cd364c41f10422f3_06E+0x71)[0x7f0ba1fca891]
/usr/local/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x129f60)[0x7f0ba20b2f60]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN7monitor17_fcefdec84997cb1d3_06E+0x5c85)[0x7f0ba105f8a5]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8ec184)[0x7f0ba106d184]
/usr/local/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN4main16_706f4ee7413ae583_06E+0x7e)[0x7f0ba106cd9e]
/usr/local/bin/../lib/librustrt.so(_Z18task_start_wrapperP10spawn_args+0x24)[0x7f0ba053f7e4]
rust: domain main @0x1cae3c0 root task failed

[jdm]

I actually meant the gdb backtrace from a breakpoint at rust_task_fail.

[AngryLawyer]

Oh. I'll see what I can do about that over the next couple of days - I've not played with GDB in some time.

[AngryLawyer]

OK, not sure if this is what you were after:

(gdb) backtrace full
#0  rust_task_fail (task=0x7fffec10ba70, 
    expr=0x7ffff70f9830 "Assertion bpos == mbc.pos || bpos.to_uint() >= mbc.pos.to_uint() + mbc.bytes failed", 
    file=0x7ffff70f9580 "/home/tony/Projects/rust/src/libsyntax/codemap.rs", 
    line=500) at /home/tony/Projects/rust/src/rt/rust_task.cpp:85
No locals.
#1  0x00007ffff5ee2109 in __morestack () from /usr/local/bin/../lib/librustrt.so
No symbol table info available.
#2  0x00007ffff5ed2d78 in call_on_c_stack (fn_ptr=0x7ffff5ed26b0, 
    args=0x7fffe415f4c0, this=0x7fffec10ba70)
    at /home/tony/Projects/rust/src/rt/rust_task.h:475
        prev_rust_sp = 0
        borrowed_a_c_stack = true
        sp = <optimised out>
#3  call_upcall_on_c_stack (fn_ptr=0x7ffff5ed26b0, args=0x7fffe415f4c0, 
    task=<optimised out>) at /home/tony/Projects/rust/src/rt/rust_upcall.cpp:45
No locals.
#4  upcall_fail (expr=<optimised out>, 
    file=0x7ffff70f9580 "/home/tony/Projects/rust/src/libsyntax/codemap.rs", 
    line=500) at /home/tony/Projects/rust/src/rt/rust_upcall.cpp:123
        task = 0x7fffec10ba70
        args = {task = 0x7fffec10ba70, 
          expr = 0x7ffff70f9830 "Assertion bpos == mbc.pos || bpos.to_uint() >= mbc.---Type <return> to continue, or q <return> to quit---
pos.to_uint() + mbc.bytes failed", 
          file = 0x7ffff70f9580 "/home/tony/Projects/rust/src/libsyntax/codemap.rs", line = 500}
#5  0x00007ffff7a13a5b in sys::begin_unwind_::_15feb4cf285334c::_06 ()
   from /usr/local/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so
No symbol table info available.
#6  0x00007ffff795c3fe in rt::rt_fail_::_f79ba45ac636dce::_06 ()
   from /usr/local/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so
No symbol table info available.
#7  0x00007ffff6ee349e in codemap::__extensions__::meth_9251::bytepos_to_local_charpos::_2ef2f680debabbad::_06 ()
   from /usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so
No symbol table info available.
#8  0x00007ffff6ee155b in codemap::__extensions__::meth_9111::lookup_pos::_fa9d322f72fd5316::_06 () from /usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so
No symbol table info available.
#9  0x00007ffff6ee1c64 in codemap::__extensions__::meth_9113::lookup_char_pos_adj::_49afbe1de9c0f59::_06 ()
   from /usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so
No symbol table info available.
#10 0x00007ffff6ede5b6 in codemap::__extensions__::meth_8514::span_to_str::_cac44644182bf88b::_06 () from /usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so
No symbol table info available.
---Type <return> to continue, or q <return> to quit---
#11 0x00007ffff6ed9fb5 in diagnostic::emit::_d2f47fc894c9320::_06 ()
   from /usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so
No symbol table info available.
#12 0x00007ffff70f81b8 in __morestack ()
   from /usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so
No symbol table info available.
#13 0x00007ffff69fd193 in monitor::anon::anon::expr_fn_89179 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#14 0x00007ffff6ed83bd in diagnostic::__extensions__::meth_8170::emit::_d2f47fc894c9320::_06 () from /usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so
No symbol table info available.
#15 0x00007ffff6ed747e in diagnostic::__extensions__::meth_8120::span_warn::_2f48a8a4d3384::_06 () from /usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so
No symbol table info available.
#16 0x00007ffff67ef93e in middle::liveness::__extensions__::warn_about_unused::anon::expr_fn_69339 () from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#17 0x00007ffff67ec174 in middle::liveness::__extensions__::meth_69212::warn_about_unused::_eaa396e49e408468::_06 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#18 0x00007ffff67ef5b6 in middle::liveness::__extensions__::warn_about_unused_or_dea---Type <return> to continue, or q <return> to quit---
d_vars_in_pat::anon::expr_fn_69337 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#19 0x00007ffff67e33dc in middle::liveness::__extensions__::pat_bindings::anon::expr_fn_68834 () from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#20 0x00007ffff6814f2a in middle::pat_util::pat_bindings::anon::expr_fn_70517 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#21 0x00007ffff6f2a205 in ast_util::walk_pat::_b8bf7b22f55e85f0::_06 ()
   from /usr/local/bin/../lib/libsyntax-84efebcb12c867a2-0.6.so
No symbol table info available.
#22 0x00007ffff67e329a in middle::liveness::__extensions__::meth_68831::pat_bindings::_ddf8809261f68fb::_06 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#23 0x00007ffff67df99c in middle::liveness::check_local::_22f6234b85df82a::_06 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#24 0x00007ffff630c226 in visit::default_visitor_27195::anon::expr_fn_27642 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#25 0x00007ffff630ace1 in visit::visit_stmt_27583::_407f2e602dd0ae55::_06 ()
---Type <return> to continue, or q <return> to quit---
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#26 0x00007ffff62fdafa in visit::visit_block_26801::_7fa773563467a885::_06 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#27 0x00007ffff67d0832 in middle::liveness::visit_fn::_24b64fce76d3c6b5::_06 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#28 0x00007ffff6309388 in visit::visit_item_27461::_7993a9ab1149fd3::_06 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#29 0x00007ffff6308c24 in visit::default_visitor_27195::anon::expr_fn_27410 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#30 0x00007ffff63093f9 in visit::visit_item_27461::_7993a9ab1149fd3::_06 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#31 0x00007ffff6308c24 in visit::default_visitor_27195::anon::expr_fn_27410 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#32 0x00007ffff63093f9 in visit::visit_item_27461::_7993a9ab1149fd3::_06 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
---Type <return> to continue, or q <return> to quit---
#33 0x00007ffff6308c24 in visit::default_visitor_27195::anon::expr_fn_27410 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#34 0x00007ffff67c648e in middle::liveness::check_crate::_1628ef44bfc587c9::_06 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#35 0x00007ffff69bc2f9 in driver::driver::compile_rest::anon::expr_fn_86790 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#36 0x00007ffff69baf38 in driver::driver::time_86660::_bd3632ba6dcca720::_06 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#37 0x00007ffff69b82e8 in driver::driver::compile_rest::_ae80a5494db8f5f0::_06 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#38 0x00007ffff69ff184 in __morestack ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#39 0x00007ffff69bc677 in driver::driver::compile_upto::_3511ccef3fbc817::_06 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#40 0x00007ffff69bca79 in driver::driver::compile_input::_da16f137dd9fced5::_06 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
---Type <return> to continue, or q <return> to quit---
No symbol table info available.
#41 0x00007ffff69ead2a in run_compiler::_a31e58461d354de::_06 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#42 0x00007ffff69fc0e1 in monitor::anon::expr_fn_89125 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#43 0x00007ffff69fa74e in task::__extensions__::try_88691::anon::expr_fn_88960 ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#44 0x00007ffff69ff184 in __morestack ()
   from /usr/local/bin/../lib/librustc-c84825241471686d-0.6.so
No symbol table info available.
#45 0x00007ffff79dee5f in task::spawn::spawn_raw::make_child_wrapper::anon::expr_fn_12299 () from /usr/local/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so
No symbol table info available.
#46 0x00007ffff7a44f60 in __morestack ()
   from /usr/local/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so
No symbol table info available.
#47 0x00007ffff5ed17e4 in task_start_wrapper (a=<optimised out>)
    at /home/tony/Projects/rust/src/rt/rust_task.cpp:162
        __PRETTY_FUNCTION__ = "void task_start_wrapper(spawn_args*)"
        env = <optimised out>
---Type <return> to continue, or q <return> to quit---
        ca = {spargs = 0x0, threw_exception = false}
        task = 0x7fffec10ba70
        threw_exception = false
#48 0x0000000000000000 in ?? ()
No symbol table info available.

I'm kinda in alien territory here. Do I need to compile Rust with debug symbols or anything to make that useful to you?

[jdm]

No, this output is the best you can get right now. Thanks!

[jdm]

And entertainingly enough, it actually shows us that emitting certain warnings about unused variables is triggering assertions when providing the extra data required.

[sanxiyn]

Is this related to #4780?

[AngryLawyer]

It does look to be a duplicate, as the APL glyphs I'm using are multibyte.

[catamorphism]

Closing as dup of #4780 -- reopen if it turns out not to be :-)