ICE: can't make T_opaque_trait with bare trait store

[kvark]

Got an ICE while porting a big project from 0.5 to 0.6. Rust log says the following:

RUST_LOG=rustc=1,::rt::backtrace rustc engine/engine.rs -L lib --out-dir lib
error: internal compiler error: can't make T_opaque_trait with bare trait store
rust: task failed at 'explicit failure', /build/src/rust-0.6/src/libsyntax/diagnostic.rs:99
/usr/lib/librustrt.so(_ZN9rust_task13begin_failureEPKcS1_m+0x4b)[0x7f74d607664b]
/usr/lib/librustrt.so(+0x2a189)[0x7f74d6087189]
/usr/lib/librustrt.so(upcall_fail+0x198)[0x7f74d60783a8]
/usr/lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x1055db)[0x7f74d927e5db]
/usr/lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x105582)[0x7f74d927e582]
/usr/lib/libcore-c3ca5d77d81b46c1-0.6.so(_ZN3sys12begin_unwind17_61fe198059b9e3fc3_06E+0x71)[0x7f74d91c6651]
/usr/lib/libsyntax-84efebcb12c867a2-0.6.so(_ZN10diagnostic14__extensions__9meth_84585fatal15_c79235bb6437b73_06E+0x196)[0x7f74d8734896]
/usr/lib/libsyntax-84efebcb12c867a2-0.6.so(_ZN10diagnostic14__extensions__9meth_84813bug15_c79235bb6437b73_06E+0x6f)[0x7f74d873502f]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6driver7session14__extensions__10meth_188433bug17_b5f71376f9f489aa3_06E+0x80)[0x7f74d7a99e50]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans6common14T_opaque_trait17_d487fd18f1d421363_06E+0x3f1)[0x7f74d7bb5691]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans7type_of14sizing_type_of15_c1bc195eb34bc63_06E+0xb8e)[0x7f74d7bc943e]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x11a75f)[0x7f74d7aa675f]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x34e4b7)[0x7f74d7cda4b7]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans3adt14represent_type17_cff2701782ac89703_06E+0x1789)[0x7f74d7b4c5c9]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans7type_of7type_of15_c1bc195eb34bc63_06E+0x17bd)[0x7f74d7ae736d]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans7type_of7type_of15_c1bc195eb34bc63_06E+0xf5e)[0x7f74d7ae6b0e]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x11a75f)[0x7f74d7aa675f]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x34f922)[0x7f74d7cdb922]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x34f4ce)[0x7f74d7cdb4ce]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans3adt9fields_of17_ffb4601ba2c964233_06E+0x3f)[0x7f74d7bd09df]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans7type_of7type_of15_c1bc195eb34bc63_06E+0x17ec)[0x7f74d7ae739c]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans7type_of7type_of15_c1bc195eb34bc63_06E+0x738)[0x7f74d7ae62e8]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans7type_of7type_of15_c1bc195eb34bc63_06E+0xf5e)[0x7f74d7ae6b0e]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans7type_of7type_of15_c1bc195eb34bc63_06E+0x3da)[0x7f74d7ae5f8a]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x11a75f)[0x7f74d7aa675f]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x34f922)[0x7f74d7cdb922]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x34f4ce)[0x7f74d7cdb4ce]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans3adt9fields_of17_ffb4601ba2c964233_06E+0x3f)[0x7f74d7bd09df]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans7type_of7type_of15_c1bc195eb34bc63_06E+0x17ec)[0x7f74d7ae739c]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans7type_of7type_of15_c1bc195eb34bc63_06E+0x738)[0x7f74d7ae62e8]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x11a75f)[0x7f74d7aa675f]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x34f922)[0x7f74d7cdb922]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x34f4ce)[0x7f74d7cdb4ce]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans3adt9fields_of17_ffb4601ba2c964233_06E+0x3f)[0x7f74d7bd09df]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans7type_of7type_of15_c1bc195eb34bc63_06E+0x17ec)[0x7f74d7ae739c]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans7type_of7type_of15_c1bc195eb34bc63_06E+0x91a)[0x7f74d7ae64ca]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans7type_of7type_of15_c1bc195eb34bc63_06E+0x3da)[0x7f74d7ae5f8a]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4expr15trans_local_var17_f79ea779daedaa9f3_06E+0x163)[0x7f74d7b9e5b3]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x20d3f2)[0x7f74d7b993f2]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x1f8b22)[0x7f74d7b84b22]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x1f6ea0)[0x7f74d7b82ea0]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x8b8b34)[0x7f74d8244b34]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4expr14trans_to_datum17_e5e293cc226c2b7b3_06E+0x321)[0x7f74d7aee861]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x20cf52)[0x7f74d7b98f52]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x1f8b22)[0x7f74d7b84b22]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x1f6ea0)[0x7f74d7b82ea0]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4expr14trans_to_datum17_e5e293cc226c2b7b3_06E+0x321)[0x7f74d7aee861]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans6callee14trans_arg_expr16_7c52c158fb4e7943_06E+0x9b3)[0x7f74d7b7f253]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4meth14trans_self_arg17_544359e931bae1b23_06E+0x120)[0x7f74d7c73920]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4meth19trans_method_callee17_63afa2148d7b3f823_06E+0x11f0)[0x7f74d7b65d60]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x1e089f)[0x7f74d7b6c89f]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x1effe2)[0x7f74d7b7bfe2]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4base10with_scope16_42e4eeeae78c8643_06E+0x56e)[0x7f74d7b3910e]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans6callee16trans_call_inner17_c39d6d201e1eca503_06E+0xc2)[0x7f74d7b6c182]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans6callee17trans_method_call17_4be16fc4341e49e93_06E+0x1fa)[0x7f74d7b6c4aa]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x1fd2d3)[0x7f74d7b892d3]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x1f7171)[0x7f74d7b83171]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4expr14trans_to_datum17_e5e293cc226c2b7b3_06E+0x321)[0x7f74d7aee861]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans6callee14trans_arg_expr16_7c52c158fb4e7943_06E+0x9b3)[0x7f74d7b7f253]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4meth14trans_self_arg17_544359e931bae1b23_06E+0x120)[0x7f74d7c73920]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4meth19trans_method_callee17_63afa2148d7b3f823_06E+0x11f0)[0x7f74d7b65d60]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x1e089f)[0x7f74d7b6c89f]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x1effe2)[0x7f74d7b7bfe2]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4base10with_scope16_42e4eeeae78c8643_06E+0x56e)[0x7f74d7b3910e]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans6callee16trans_call_inner17_c39d6d201e1eca503_06E+0xc2)[0x7f74d7b6c182]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans6callee17trans_method_call17_4be16fc4341e49e93_06E+0x1fa)[0x7f74d7b6c4aa]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x1fd2d3)[0x7f74d7b892d3]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4expr10trans_into16_54d763e594233573_06E+0xe97)[0x7f74d7aeb6c7]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4base10init_local15_3c07168daf987d3_06E+0x65f)[0x7f74d7bee32f]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x26461b)[0x7f74d7bf061b]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4base10trans_stmt17_2c2aa18584fe5be63_06E+0x5ae)[0x7f74d7aea3fe]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x15d43c)[0x7f74d7ae943c]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans11controlflow11trans_block16_a4e9a67bdd72ccb3_06E+0x19e)[0x7f74d7ae7bae]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x8b8b34)[0x7f74d8244b34]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4base13trans_closure17_85d646a672f846683_06E+0x50e)[0x7f74d7bf96ee]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4base8trans_fn17_fe1e7f81b93e452d3_06E+0x3b9)[0x7f74d7aa1449]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4meth12trans_method17_bea14be21fcde8563_06E+0x40d)[0x7f74d7adf21d]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x2e768d)[0x7f74d7c7368d]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4meth10trans_impl16_fe66dbbe5a7fa333_06E+0x14e)[0x7f74d7c0001e]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4base10trans_item16_ed7df62f5f126563_06E+0x69d)[0x7f74d7a98a2d]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4base9trans_mod17_33f95ffa6ea6f19d3_06E+0xa3)[0x7f74d7c00263]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4base10trans_item16_ed7df62f5f126563_06E+0x46e)[0x7f74d7a987fe]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4base9trans_mod17_33f95ffa6ea6f19d3_06E+0xa3)[0x7f74d7c00263]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6middle5trans4base11trans_crate15_aa5d2b86af98143_06E+0x13c4)[0x7f74d7c1ff14]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x87a290)[0x7f74d8206290]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6driver6driver12compile_rest17_b2b258b84b35f3533_06E+0x331e)[0x7f74d820329e]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x8b8b34)[0x7f74d8244b34]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6driver6driver12compile_upto17_12335154b455986e3_06E+0x108)[0x7f74d82064a8]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x8b8b34)[0x7f74d8244b34]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN6driver6driver13compile_input15_bb29edf7a232863_06E+0xca)[0x7f74d82068ea]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN12run_compiler17_64d52739a36d169c3_06E+0x20aa)[0x7f74d8235fca]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x8b6601)[0x7f74d8242601]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x8b2e2c)[0x7f74d823ee2c]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x8b8b34)[0x7f74d8244b34]
/usr/lib/libcore-c3ca5d77d81b46c1-0.6.so(+0xce08e)[0x7f74d924708e]
/usr/lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x14dcb4)[0x7f74d92c6cb4]
/usr/lib/librustrt.so(_Z18task_start_wrapperP10spawn_args+0x24)[0x7f74d6076e64]
rust: task failed at 'explicit failure', /build/src/rust-0.6/src/librustc/rustc.rc:357
/usr/lib/librustrt.so(_ZN9rust_task13begin_failureEPKcS1_m+0x4b)[0x7f74d607664b]
/usr/lib/librustrt.so(+0x2a189)[0x7f74d6087189]
/usr/lib/librustrt.so(upcall_fail+0x198)[0x7f74d60783a8]
/usr/lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x1055db)[0x7f74d927e5db]
/usr/lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x105582)[0x7f74d927e582]
/usr/lib/libcore-c3ca5d77d81b46c1-0.6.so(_ZN3sys12begin_unwind17_61fe198059b9e3fc3_06E+0x71)[0x7f74d91c6651]
/usr/lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x14dcb4)[0x7f74d92c6cb4]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN7monitor17_78935df9ff9e1afa3_06E+0x1577)[0x7f74d82385f7]
/usr/lib/librustc-c84825241471686d-0.6.so(+0x8b8b34)[0x7f74d8244b34]
/usr/lib/librustc-c84825241471686d-0.6.so(_ZN4main15_c4de63b748e03d3_06E+0x7e)[0x7f74d824474e]
/usr/lib/librustrt.so(_Z18task_start_wrapperP10spawn_args+0x24)[0x7f74d6076e64]
rust: domain main @0x23743c0 root task failed
make: *** [engine-code] Error 101

[kvark]

I was able to procude a simple testcase:
trait Curve {}
enum E {X(Curve)}
fn main() {}

Now I see why this is wrong, it would be nice to have a proper error message for this case.

[euphoris]

a similar case:

struct Struct {
    r: io::Reader
}

fn new_struct(r: io::Reader) -> Struct {
    Struct { r: r }
}

[nikomatsakis]

Can you re-test this with incoming? That particular ICE is no longer
relevant, but there may be some similar bug that occurs.

[catamorphism]

This is fixed. Added a test case in #7863 -- this can close when it lands.

[catamorphism]

Forgot to close this. Closing now.