rustc hangs

[aochagavia]

OS: Windows 10 x64
rustc: rustc 1.9.0 (e4e8b6668 2016-05-18) and rustc 1.11.0-nightly (ab0b87458 2016-06-13).

First of all I am sorry I was unable to come up with a minimal example. I tried a couple of times but it just didn't trigger the issue. I am working on a simple game, but instead of compiling in <10 seconds (as usual), it hangs indefinetly (I gave up after about 5 minutes).

Running with time-passes

When compiling with nightly, the output of cargo rustc -- -Ztime-passes is:

time: 0.032; rss: 27MB  parsing
time: 0.000; rss: 27MB  configuration 1
time: 0.000; rss: 27MB  recursion limit
time: 0.000; rss: 27MB  crate injection
time: 0.000; rss: 27MB  plugin loading
time: 0.000; rss: 27MB  plugin registration
time: 0.214; rss: 54MB  expansion
time: 0.000; rss: 54MB  gated configuration checking
time: 0.000; rss: 54MB  maybe building test harness
time: 0.000; rss: 54MB  checking for inline asm in case the target doesn't support it
time: 0.000; rss: 54MB  complete gated feature checking
time: 0.000; rss: 54MB  assigning node ids
time: 0.000; rss: 54MB  collecting defs
time: 0.849; rss: 131MB external crate/lib resolution
time: 0.000; rss: 131MB early lint checks
time: 0.000; rss: 131MB AST validation
^C

As you can see, the compiler is stuck after AST validation (note how I needed ^C to kill Cargo).

When compiling with stable, the output is:

time: 0.003; rss: 41MB  parsing
time: 0.000; rss: 42MB  configuration 1
time: 0.000; rss: 42MB  recursion limit
time: 0.000; rss: 42MB  gated macro checking
time: 0.000; rss: 42MB  crate injection
time: 0.020; rss: 43MB  macro loading
time: 0.000; rss: 43MB  plugin loading
time: 0.000; rss: 43MB  plugin registration
time: 0.005; rss: 44MB  expansion
time: 0.000; rss: 44MB  complete gated feature checking 1
time: 0.001; rss: 44MB  configuration 2
time: 0.000; rss: 44MB  gated configuration checking
time: 0.000; rss: 44MB  maybe building test harness
time: 0.001; rss: 44MB  prelude injection
time: 0.000; rss: 44MB  checking that all macro invocations are gone
time: 0.000; rss: 44MB  checking for inline asm in case the target doesn't support it
time: 0.000; rss: 44MB  complete gated feature checking 2
time: 0.000; rss: 44MB  const fn bodies and arguments
time: 0.000; rss: 44MB  assigning node ids
time: 0.000; rss: 44MB  lowering ast -> hir
time: 0.000; rss: 44MB  indexing hir
time: 0.000; rss: 44MB  attribute checking
time: 0.000; rss: 44MB  early lint checks
time: 0.144; rss: 50MB  external crate/lib resolution
time: 0.000; rss: 50MB  language item collection
^C

Additional information (tested on stable):

If I remove the controllers::keyboard module, the compiler runs without problems.

If I replace this line by pub fn press(key: u8) {, the output with -Ztime-passes changes:

time: 0.003; rss: 41MB  parsing
time: 0.000; rss: 42MB  configuration 1
time: 0.000; rss: 42MB  recursion limit
time: 0.000; rss: 42MB  gated macro checking
time: 0.000; rss: 42MB  crate injection
time: 0.020; rss: 43MB  macro loading
time: 0.000; rss: 43MB  plugin loading
time: 0.000; rss: 43MB  plugin registration
time: 0.004; rss: 44MB  expansion
time: 0.000; rss: 44MB  complete gated feature checking 1
time: 0.001; rss: 44MB  configuration 2
time: 0.000; rss: 44MB  gated configuration checking
time: 0.000; rss: 44MB  maybe building test harness
time: 0.001; rss: 44MB  prelude injection
time: 0.000; rss: 44MB  checking that all macro invocations are gone
time: 0.000; rss: 44MB  checking for inline asm in case the target doesn't support it
time: 0.000; rss: 44MB  complete gated feature checking 2
time: 0.000; rss: 44MB  const fn bodies and arguments
time: 0.000; rss: 44MB  assigning node ids
time: 0.000; rss: 44MB  lowering ast -> hir
time: 0.000; rss: 44MB  indexing hir
time: 0.000; rss: 44MB  attribute checking
time: 0.000; rss: 44MB  early lint checks
time: 0.144; rss: 50MB  external crate/lib resolution
time: 0.000; rss: 50MB  language item collection
time: 0.020; rss: 66MB  resolution
time: 0.000; rss: 66MB  lifetime resolution
time: 0.000; rss: 66MB  looking for entry point
time: 0.000; rss: 66MB  looking for plugin registrar
time: 0.000; rss: 66MB  region resolution
time: 0.000; rss: 66MB  loop checking
time: 0.000; rss: 66MB  static item recursion checking
time: 0.000; rss: 66MB  load_dep_graph
time: 0.003; rss: 66MB  type collecting
time: 0.000; rss: 66MB  variance inference
time: 0.094; rss: 101MB coherence checking
time: 0.001; rss: 101MB wf checking
time: 0.002; rss: 101MB item-types checking
^C

For whatever reason, rustc is able to go a little bit further in this case.

Related issues

Maybe this is a duplicate of #33776

[jseyfried]

I'll investigate.

[aochagavia]

@jseyfried Thanks! A short update (now using rustc 1.11.0-nightly (1ab87b65a 2016-07-02))

It may be interesting to note that I was importing piston_window::keyboard::key instead of piston_window::keyboard::Key (the former is wrong). Anyway, both cases trigger the issue.

Surprisingly, the code compiles after some changes (see the repo at the latest commit). You can see a diff here. After seeing this, I thought that the problem was solved by removing the piston dependency (see Cargo.toml and main.rs). However, I tested removing the piston dependency in the old code and it still triggered the issue.

In other words, adding modules and new dependencies randomly got my crate to compile.

[arielb1]

1.11 is now beta

[pnkfelix]

triage: P-high

[eddyb]

My suggestion here is to run it under a debugger and stop after it has been hung for a while, to get a backtrace.

[pnkfelix]

regression; needs to be investigated. @jseyfried are you still planning to try to look at this? (I think @arielb1 will also look at it in parallel.)

[jseyfried]

@pnkfelix Yeah, I'm planning on working on this over the weekend.
I'll be sure to leave a comment on this issue as soon as I have a idea what's going on so @arielb1 and I don't duplicate work.

[brson]

@jseyfried make any progress on this last week?

[jseyfried]

@brson sorry for the delay on this.

[jseyfried]

I'm having trouble reproducing this (I've tried on a two different Linux machines).
Can someone else try to reproduce it? (cc @arielb1)

[arielb1]

I was also not able to reproduce. Could you help us @aochagavia?

[aochagavia]

I tried to reproduce it, but the compiler hit an ICE when compiling xml-rs v0.3.4, which is one of the dependencies, so I can't check if the current nightly is still wrong.

[eddyb]

@aochagavia What about nightlies from a few days ago?

[aochagavia]

Using rustc 1.11.0-nightly (ab0b87458 2016-06-13) triggers the issue (testing on this commit) on my machine (Windows 10 x64). I am using the GNU ABI.

[sanxiyn]

I too can't reproduce on Linux. All of stable, beta, nightly-2016-06-14 terminates promptly with 3 errors.

[eddyb]

Is it entirely Windows-specific?

[pnkfelix]

(reassinging to niko in hopes that he can reproduce it on his windows box)

[brson]

My results building cd1b56c39d02cb7b6a0aa06b32f3e02e36b986e3 with the command cargo build:

• 1.9.0-i686-pc-windows-msvc - resolve errors in snake, keyboard.rs
• 1.9.0-i686-pc-windows-gnu - build errors
• 1.9.0-x86_64-pc-windows-gnu - build errors
• nightly-x86_64-pc-windows-gnu (b5ad277 2016-07-16) - build success
• nightly-x86_64-pc-windows-gnu (936bfea 2016-07-20) - ICE resolving keyboard.rs
• nightly-i686-pc-windowws-gnu (936bfea 2016-07-20) - ICE
• nightly-x86_64-pc-widows-msvc (936bfea 2016-07-20) - ICE.

No hangs. I didn't try to find the exact nightly used in the OP, but used a more recent one.

[brson]

• nightly-x86_64-pc-windows-gnu (ab0b874 2016-06-13) - build errors
• nightly-i686-pc-windows-gnu (ab0b874 2016-06-13) - build errors

[arielb1]

ICE?

[jseyfried]

@brson @arielb1 The ICE is fixed by #34963~~, which has been approved but is having trouble landing due to spurious build-bot failures~~.

[nikomatsakis]

We're going to lower the priority, since we can't seem to reproduce it and it is not blocking @aochagavia (right?). @aochagavia if you are able to at least get a backtrace, that would certainly be helpful. Otherwise, we'll have to see if it occurs more often or elsewhere!

[nikomatsakis]

triage: P-medium

[aidanhs]

$ rustc --version
rustc 1.12.0-nightly (28ce3e8a5 2016-08-01)
$ RUST_LOG=debug OUT_DIR=$(pwd)/target/debug/build/ayzim-62448a58f04ea64b/out rustc src/lib.rs --crate-name ayzim --crate-type lib -g --out-dir /home/aidanhs/Desktop/rust/ayzim-opt/target/debug/deps --emit=dep-info,link -L dependency=/home/aidanhs/Desktop/rust/ayzim-opt/target/debug/deps [...] --verbose -Z verbose -Z time--passes
time: 0.025; rss: 67MB  parsing
time: 0.004; rss: 71MB  configuration
[...]
time: 0.020; rss: 143MB wf checking
time: 0.015; rss: 145MB item-types checking

$ pstree -p 16871
rustc(16871)───rustc(16872)───{rustc}(16873)
$ sudo gdb -p 16871 --batch -ex bt
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
0x00007f808256be8c in __libc_waitpid (pid=16872, stat_loc=0x7ffc614a9d7c, options=0) at ../sysdeps/unix/sysv/linux/waitpid.c:31
31      ../sysdeps/unix/sysv/linux/waitpid.c: No such file or directory.
#0  0x00007f808256be8c in __libc_waitpid (pid=16872, stat_loc=0x7ffc614a9d7c, options=0) at ../sysdeps/unix/sysv/linux/waitpid.c:31
#1  0x0000555a9c9fff7b in std::process::Child::wait::h3efe8d2fdb58555e ()
#2  0x0000555a9c5fcf36 in rustup_init::proxy_mode::direct_proxy::h37bbd13facb3f408 ()
#3  0x0000555a9c5b9747 in rustup_init::run_multirust::h70cbf6663515e18b ()
#4  0x0000555a9c5b6ee2 in rustup_init::main::h81d74e5ca7cf36c2 ()
#5  0x0000555a9ca0b485 in std::sys_common::unwind::try::try_fn::h04c0c89e4add6cc4 ()
#6  0x0000555a9ca02c6c in __rust_try ()
#7  0x0000555a9ca0aecc in std::rt::lang_start::h61f4934e780b4dfc ()
#8  0x00007f8081fa2f45 in __libc_start_main (main=0x555a9c5baf10 <main>, argc=45, argv=0x7ffc614afa08, init=<optimised out>, fini=<optimised out>, rtld_fini=<optimised out>, stack_end=0x7ffc614af9f8) at libc-start.c:287
#9  0x0000555a9c5b6dd5 in _start ()
$ sudo gdb -p 16872 --batch -ex bt
[New LWP 16873]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
0x00007fd6576df65b in pthread_join (threadid=140558540470016, thread_return=0x0) at pthread_join.c:92
92      pthread_join.c: No such file or directory.
#0  0x00007fd6576df65b in pthread_join (threadid=140558540470016, thread_return=0x0) at pthread_join.c:92
#1  0x00007fd66026f5cb in std::sys::thread::Thread::join::h22a49811a1b525c8 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/libstd-c8005792.so
#2  0x00007fd66080a09a in rustc_driver::run::hebe6a2a70ce6ae1e () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_driver-c8005792.so
#3  0x00007fd6608186ed in rustc_driver::main::h2290eb64ff3fc98a () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_driver-c8005792.so
#4  0x00007fd660271609 in std::panicking::try::call::h5df3ac2979db3c90 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/libstd-c8005792.so
#5  0x00007fd660281187 in __rust_maybe_catch_panic () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/libstd-c8005792.so
#6  0x00007fd66027075d in std::rt::lang_start::hfe9ab243c60ffb9b () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/libstd-c8005792.so
#7  0x00007fd65fdd1f45 in __libc_start_main (main=0x559ff04908d0 <main>, argc=47, argv=0x7ffeb624b7f8, init=<optimised out>, fini=<optimised out>, rtld_fini=<optimised out>, stack_end=0x7ffeb624b7e8) at libc-start.c:287
#8  0x0000559ff0490779 in _start ()
$ sudo gdb -p 16873 --batch -ex bt                                                                                                                
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
0x00007fd65fe9b72d in write () at ../sysdeps/unix/syscall-template.S:81
81      ../sysdeps/unix/syscall-template.S: No such file or directory.
#0  0x00007fd65fe9b72d in write () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007fd660247401 in _$LT$std..io..stdio..Stderr$u20$as$u20$std..io..Write$GT$::write::hd0e839e43939c007 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-u
nknown-linux-gnu/lib/libstd-c8005792.so
#2  0x00007fd65628a73d in _$LT$term..terminfo..TerminfoTerminal$LT$T$GT$$u20$as$u20$std..io..Write$GT$::write::hdd258bedc9595a9c () from /home/aidanhs/.multirust/toolchai
ns/nightly-x86_64-unknown-linux-gnu/lib/libterm-c8005792.so
#3  0x00007fd657fec1e3 in _$LT$std..io..Write..write_fmt..Adaptor$LT$$u27$a$C$$u20$T$GT$$u20$as$u20$core..fmt..Write$GT$::write_str::h312bc07629475bdf () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_errors-c8005792.so
#4  0x00007fd6602e8e08 in core::fmt::write::h955c581c22098b7a () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/libstd-c8005792.so
#5  0x00007fd657fe9d63 in std::io::Write::write_fmt::hfee6c576dc30ba81 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_errors-c8
005792.so
#6  0x00007fd657ff7924 in rustc_errors::emitter::emit_to_destination::h38d36f33b3cf5586 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/l
ibrustc_errors-c8005792.so
#7  0x00007fd657ff6445 in rustc_errors::emitter::EmitterWriter::emit_message_old_school::hf000ccfd00396981 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unkn
own-linux-gnu/lib/librustc_errors-c8005792.so
#8  0x00007fd657fee7ea in _$LT$rustc_errors..emitter..EmitterWriter$u20$as$u20$rustc_errors..emitter..Emitter$GT$::emit::hb6bf465c9fd02120 () from /home/aidanhs/.multirus
t/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_errors-c8005792.so
#9  0x00007fd657ffc330 in rustc_errors::DiagnosticBuilder::emit::h92f9c1795d5aff70 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librus
tc_errors-c8005792.so
#10 0x00007fd65c9871ed in rustc::infer::InferCtxt::report_mismatched_types::h0b609f1ce41bfd4e () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu
/lib/librustc-c8005792.so
#11 0x00007fd65e617b9c in rustc_typeck::check::demand::_$LT$impl$u20$rustc_typeck..check..FnCtxt$LT$$u27$a$C$$u20$$u27$gcx$C$$u20$$u27$tcx$GT$$GT$::demand_eqtype_with_ori
gin::h9ab18fcb8f617943 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_typeck-c8005792.so
#12 0x00007fd65e5fb487 in rustc_typeck::check::_match::_$LT$impl$u20$rustc_typeck..check..FnCtxt$LT$$u27$a$C$$u20$$u27$gcx$C$$u20$$u27$tcx$GT$$GT$::check_pat_tuple_struct
::h314035dae70bea90 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_typeck-c8005792.so
#13 0x00007fd65e5f887f in rustc_typeck::check::_match::_$LT$impl$u20$rustc_typeck..check..FnCtxt$LT$$u27$a$C$$u20$$u27$gcx$C$$u20$$u27$tcx$GT$$GT$::check_pat::h7b18286e9f
b261f3 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_typeck-c8005792.so
#14 0x00007fd65e5fb654 in rustc_typeck::check::_match::_$LT$impl$u20$rustc_typeck..check..FnCtxt$LT$$u27$a$C$$u20$$u27$gcx$C$$u20$$u27$tcx$GT$$GT$::check_pat_tuple_struct
::h314035dae70bea90 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_typeck-c8005792.so
#15 0x00007fd65e5f887f in rustc_typeck::check::_match::_$LT$impl$u20$rustc_typeck..check..FnCtxt$LT$$u27$a$C$$u20$$u27$gcx$C$$u20$$u27$tcx$GT$$GT$::check_pat::h7b18286e9f
b261f3 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_typeck-c8005792.so
#16 0x00007fd65e5f9793 in rustc_typeck::check::_match::_$LT$impl$u20$rustc_typeck..check..FnCtxt$LT$$u27$a$C$$u20$$u27$gcx$C$$u20$$u27$tcx$GT$$GT$::check_pat::h7b18286e9f
b261f3 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_typeck-c8005792.so
#17 0x00007fd65e5fb654 in rustc_typeck::check::_match::_$LT$impl$u20$rustc_typeck..check..FnCtxt$LT$$u27$a$C$$u20$$u27$gcx$C$$u20$$u27$tcx$GT$$GT$::check_pat_tuple_struct
::h314035dae70bea90 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_typeck-c8005792.so
#18 0x00007fd65e5f887f in rustc_typeck::check::_match::_$LT$impl$u20$rustc_typeck..check..FnCtxt$LT$$u27$a$C$$u20$$u27$gcx$C$$u20$$u27$tcx$GT$$GT$::check_pat::h7b18286e9f
b261f3 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_typeck-c8005792.so
#19 0x00007fd65e5fa763 in rustc_typeck::check::_match::_$LT$impl$u20$rustc_typeck..check..FnCtxt$LT$$u27$a$C$$u20$$u27$gcx$C$$u20$$u27$tcx$GT$$GT$::check_match::h541c2744
e41fdabc () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_typeck-c8005792.so
#20 0x00007fd65e6825ec in rustc_typeck::check::FnCtxt::check_expr_with_expectation_and_lvalue_pref::hf9af8b059be90a47 () from /home/aidanhs/.multirust/toolchains/nightly-
x86_64-unknown-linux-gnu/lib/librustc_typeck-c8005792.so
#21 0x00007fd65e68777e in rustc_typeck::check::FnCtxt::check_decl_initializer::hba36f65b1576a6af () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-
gnu/lib/librustc_typeck-c8005792.so
#22 0x00007fd65e68782e in rustc_typeck::check::FnCtxt::check_decl_local::h2a0e3673e09cd8bc () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/li
b/librustc_typeck-c8005792.so
#23 0x00007fd65e687a89 in rustc_typeck::check::FnCtxt::check_stmt::hd7eaaa481f8ccc18 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/libr
ustc_typeck-c8005792.so
#24 0x00007fd65e687e84 in rustc_typeck::check::FnCtxt::check_block_with_expected::h55da64af5446ca47 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-lin
ux-gnu/lib/librustc_typeck-c8005792.so
#25 0x00007fd65e678c3b in rustc_typeck::check::FnCtxt::check_then_else::h1653533aed17af75 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib
/librustc_typeck-c8005792.so
#26 0x00007fd65e682644 in rustc_typeck::check::FnCtxt::check_expr_with_expectation_and_lvalue_pref::hf9af8b059be90a47 () from /home/aidanhs/.multirust/toolchains/nightly-
x86_64-unknown-linux-gnu/lib/librustc_typeck-c8005792.so
#27 0x00007fd65e678cb6 in rustc_typeck::check::FnCtxt::check_then_else::h1653533aed17af75 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib
/librustc_typeck-c8005792.so
#28 0x00007fd65e682644 in rustc_typeck::check::FnCtxt::check_expr_with_expectation_and_lvalue_pref::hf9af8b059be90a47 () from /home/aidanhs/.multirust/toolchains/nightly-
x86_64-unknown-linux-gnu/lib/librustc_typeck-c8005792.so
#29 0x00007fd65e688072 in rustc_typeck::check::FnCtxt::check_block_with_expected::h55da64af5446ca47 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-lin
ux-gnu/lib/librustc_typeck-c8005792.so
#30 0x00007fd65e660dc7 in rustc_typeck::check::check_fn::h6c476956211c7381 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_typec
k-c8005792.so
#31 0x00007fd65e65f567 in rustc_typeck::check::check_bare_fn::h952d7c729d98a4e9 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_
typeck-c8005792.so
#32 0x00007fd65e66577f in rustc_typeck::check::check_item_body::h26c5d995a8cf2591 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librust
c_typeck-c8005792.so
#33 0x00007fd65e65e07e in rustc_typeck::check::check_item_bodies::h879e0600ff9f7c52 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/libru
stc_typeck-c8005792.so
#34 0x00007fd65e6d5486 in rustc_typeck::check_crate::hcd055bbbc96bb85b () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_typeck-c8
005792.so
#35 0x00007fd6608257ec in rustc_driver::driver::phase_3_run_analysis_passes::_$u7b$$u7b$closure$u7d$$u7d$::h7f2cec505064b4bf () from /home/aidanhs/.multirust/toolchains/n
ightly-x86_64-unknown-linux-gnu/lib/librustc_driver-c8005792.so
#36 0x00007fd660783e0c in rustc::ty::context::TyCtxt::create_and_enter::hab8fd8369376d0f6 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib
/librustc_driver-c8005792.so
#37 0x00007fd6607e682d in rustc_driver::driver::compile_input::hb4cc34cf85dc1edf () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc
_driver-c8005792.so
#38 0x00007fd66080c178 in rustc_driver::run_compiler::h50f95674bd902ab5 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_driver-c
8005792.so
#39 0x00007fd66075785e in std::panicking::try::call::h4577500a5284c6ff () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/librustc_driver-c8
005792.so
#40 0x00007fd660281187 in __rust_maybe_catch_panic () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/libstd-c8005792.so
#41 0x00007fd660772570 in _$LT$F$u20$as$u20$alloc..boxed..FnBox$LT$A$GT$$GT$::call_box::h24f3eb0b42327962 () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unkno
wn-linux-gnu/lib/librustc_driver-c8005792.so
#42 0x00007fd66026f478 in std::sys::thread::Thread::new::thread_start::h8f3bd45211e9f5ea () from /home/aidanhs/.multirust/toolchains/nightly-x86_64-unknown-linux-gnu/lib/
libstd-c8005792.so
#43 0x00007fd6576de184 in start_thread (arg=0x7fd655dff700) at pthread_create.c:312
#44 0x00007fd65feaa37d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

I've commented out all use of plugins in my crate, though I use a bunch of nightly features.

Looking at strace output, it appears the bottom child is blocking on writeing errors to the top process, whereas the top level process is wait4ing on the middle process and the middle process is blocked on a futex. So deadlock. This is supported by my cpu being completely idle.

Maybe there are too many errors?

$ for i in $(seq 1 1000); do echo "fn x$i() { a }" >> t.rs; done
$ rustc -Z time-passes t.rs
time: 0.005; rss: 63MB  parsing
[...]
time: 0.000; rss: 102MB AST validation

This isn't the same hang location I'm encountering in practice (item-types checking per beginning of this comment), but it is the same as one of the examples in the first comment of this issue.

[arielb1]

The "too many errors" does not hang on my computer

[arielb1]

Ah 16871 is rustup.

[arielb1]

moved to rust-lung-nursery/rustup.rs#639