remexre
commented
6 years ago I'm the bystander; I built a rustc from 9af8d42ec7 with debuginfo, it looks like it's getting stuck during macro expansion while resolving macro imports? The full stack trace of the non-sleeping thread is:
#0 0x00007fd72af105c8 in __memcmp_avx2_movbe () from /usr/lib/libc.so.6
#1 0x00007fd72a0a719c in <[u8] as core::slice::SliceOrd<u8>>::compare (self=...,
other=...) at /home/nathan/Projects/rust/src/libcore/slice/mod.rs:2887
#2 core::slice::<impl core::cmp::Ord for [T]>::cmp (self=..., other=...)
at /home/nathan/Projects/rust/src/libcore/slice/mod.rs:2759
#3 core::str::traits::<impl core::cmp::Ord for str>::cmp (self=..., other=...)
at /home/nathan/Projects/rust/src/libcore/str/mod.rs:1597
#4 core::str::traits::<impl core::cmp::PartialOrd for str>::partial_cmp (
self=..., other=...) at /home/nathan/Projects/rust/src/libcore/str/mod.rs:1625
#5 core::cmp::PartialOrd::lt (self=..., other=...)
at /home/nathan/Projects/rust/src/libcore/cmp.rs:645
#6 core::cmp::impls::<impl core::cmp::PartialOrd<&'b B> for &'a A>::lt (
self=<optimized out>, other=<optimized out>)
at /home/nathan/Projects/rust/src/libcore/cmp.rs:923
#7 <syntax_pos::symbol::InternedString as core::cmp::PartialOrd>::lt (
self=<optimized out>, __arg_0=<optimized out>)
at /home/nathan/Projects/rust/src/libsyntax_pos/symbol.rs:352
#8 core::tuple::<impl core::cmp::PartialOrd for (A, B)>::lt (
other=<optimized out>, self=<optimized out>)
at /home/nathan/Projects/rust/src/libcore/tuple.rs:92
#9 <[T] as core::slice::SliceExt>::sort_unstable_by_key::{{closure}} (
a=<optimized out>, b=<optimized out>)
at /home/nathan/Projects/rust/src/libcore/slice/mod.rs:754
#10 core::slice::sort::partition_in_blocks (v=..., pivot=<optimized out>,
is_less=<optimized out>)
at /home/nathan/Projects/rust/src/libcore/slice/sort.rs:300
#11 core::slice::sort::partition (v=..., pivot=..., is_less=<optimized out>)
at /home/nathan/Projects/rust/src/libcore/slice/sort.rs:422
#12 core::slice::sort::recurse (v=..., is_less=0x7fd7205f7120, pred=..., limit=10)
at /home/nathan/Projects/rust/src/libcore/slice/sort.rs:667
#13 0x00007fd72a08fcaa in core::slice::sort::quicksort (v=..., is_less=...)
at /home/nathan/Projects/rust/src/libcore/slice/sort.rs:702
#14 <[T] as core::slice::SliceExt>::sort_unstable_by_key (self=..., f=...)
at /home/nathan/Projects/rust/src/libcore/slice/mod.rs:754
#15 alloc::slice::<impl [T]>::sort_unstable_by_key (self=..., f=...)
at /home/nathan/Projects/rust/src/liballoc/slice.rs:1434
#16 rustc_resolve::ModuleData::for_each_child_stable (self=<optimized out>, f=...)
at librustc_resolve/lib.rs:987
#17 rustc_resolve::Resolver::lookup_import_candidates (lookup_name=...,
namespace=rustc_resolve::Namespace::TypeNS, self=<optimized out>,
filter_fn=...) at librustc_resolve/lib.rs:3596
#18 rustc_resolve::Resolver::resolve_path (self=<optimized out>, path=...,
opt_ns=...,
record_used=<error reading variable: access outside bounds of object referenced via synthetic pointer>, path_span=...) at librustc_resolve/lib.rs:3092
#19 0x00007fd72a0c8542 in rustc_resolve::resolve_imports::ImportResolver::resolve_import (directive=0x7fd6f6a8ed70, self=<optimized out>)
at librustc_resolve/resolve_imports.rs:538
#20 rustc_resolve::resolve_imports::ImportResolver::resolve_imports (
self=0x7fd7205f7378) at librustc_resolve/resolve_imports.rs:468
#21 0x00007fd72a068ba5 in rustc_resolve::macros::<impl syntax::ext::base::Resolver ---Type <return> to continue, or q <return> to quit---
for rustc_resolve::Resolver<'a>>::resolve_imports (self=<optimized out>)
at librustc_resolve/macros.rs:206
#22 0x00007fd7260749f4 in syntax::ext::expand::MacroExpander::resolve_imports (
self=0x7fd7205f81c0) at libsyntax/ext/expand.rs:388
#23 syntax::ext::expand::MacroExpander::expand (self=<optimized out>,
expansion=...) at libsyntax/ext/expand.rs:281
#24 0x00007fd726072c83 in syntax::ext::expand::MacroExpander::expand_crate (
self=0x7fd7205f81c0, krate=...) at libsyntax/ext/expand.rs:245
#25 0x00007fd72b5a3039 in rustc_driver::driver::phase_2_configure_and_expand::{{closure}} () at librustc_driver/driver.rs:780
#26 0x00007fd72b589650 in rustc::util::common::time (do_it=<optimized out>,
what=..., f=...) at /home/nathan/Projects/rust/src/librustc/util/common.rs:120
#27 0x00007fd72b62dad8 in rustc_driver::driver::phase_2_configure_and_expand (
sess=<optimized out>, cstore=<optimized out>, krate=..., registry=...,
crate_name=..., addl_plugins=..., make_glob_map=<optimized out>,
after_expand=...) at librustc_driver/driver.rs:739
#28 rustc_driver::driver::compile_input (sess=<optimized out>,
cstore=0x7fd7205fa801, input_path=<optimized out>, input=<optimized out>,
outdir=<optimized out>, output=<optimized out>, addl_plugins=...,
control=<optimized out>) at librustc_driver/driver.rs:162
#29 0x00007fd72b6366ad in rustc_driver::run_compiler (args=..., callbacks=...,
file_loader=..., emitter_dest=...) at librustc_driver/lib.rs:248
#30 0x00007fd72b534ee6 in rustc_driver::main::{{closure}} ()
at librustc_driver/lib.rs:1305
#31 rustc_driver::run::{{closure}} () at librustc_driver/lib.rs:132
#32 rustc_driver::monitor::{{closure}} () at librustc_driver/lib.rs:1212
#33 std::sys_common::backtrace::__rust_begin_short_backtrace (f=...)
at /home/nathan/Projects/rust/src/libstd/sys_common/backtrace.rs:133
#34 0x00007fd72b209b9f in __rust_maybe_catch_panic (f=0x49,
data=0x7fd71f337ce0 "IsCallable\000", data_ptr=0x7fd7205fe9f8,
vtable_ptr=0x7fd7205fe9f0) at libpanic_unwind/lib.rs:102
#35 0x00007fd72b583e37 in std::panicking::try (f=...)
at /home/nathan/Projects/rust/src/libstd/panicking.rs:458
#36 std::panic::catch_unwind (f=...)
at /home/nathan/Projects/rust/src/libstd/panic.rs:358
#37 std::thread::Builder::spawn::{{closure}} ()
at /home/nathan/Projects/rust/src/libstd/thread/mod.rs:405
#38 <F as alloc::boxed::FnBox<A>>::call_box (self=0x7fd720716b60,
args=<optimized out>) at /home/nathan/Projects/rust/src/liballoc/boxed.rs:817
#39 0x00007fd72b1de438 in _$LT$alloc..boxed..Box$LT$alloc..boxed..FnBox$LT$A$C$$u20$Output$u3d$R$GT$$u20$$u2b$$u20$$u27$a$GT$$u20$as$u20$core..ops..function..FnOnce$LT$A$GT$$GT$::call_once::h2c212c9eabf9bacb (
self=<error reading variable: access outside bounds of object referenced via synthetic pointer>, args=<optimized out>)
at /home/nathan/Projects/rust/src/liballoc/boxed.rs:827
#40 std::sys_common::thread::start_thread (main=0x7fd72062b040 "`kq \327\177\000")
at libstd/sys_common/thread.rs:24
#41 0x00007fd72b1e7249 in std::sys::unix::thread::Thread::new::thread_start (
main=0x7fd71f337ce0) at libstd/sys/unix/thread.rs:90
#42 0x00007fd7251d808c in start_thread () from /usr/lib/libpthread.so.0
#43 0x00007fd72aeb2e1f in clone () from /usr/lib/libc.so.6
Let my start by saying that I'm NOT asking for help with my project, and I KNOW my code is broken. I just want rustc to give me an error message instead of deadlocking. :)
I found this while trying to make a version of Servo without JavaScript. I started by deleting all references to mozjs from .toml files and deleting all "use js::" lines from .rs files. That should* cause the compile to fail almost right away with compile errors. Instead, rustc just hangs when it reaches the "script" crate.
OS and RustC version This is 64-bit Linux Mint 18, corresponding to Ubuntu 16.04. My rustc version is rustc 1.23.0 (766bd11c8 2018-01-01).
To Reproduce
Expected Results Compilation should fail as soon as it hits the "script" crate with a huge number of error messages.
Actual Results rustc just hangs. Instead of the expected CPU utilization (8 threads going full blast) there is only one thread. When I attach gdb to the rustc process, I see only two threads. One thread is stuck on a pthread_join, and another thread is in a loop that seems to call memcmp a lot.
A Second Opinion A very kind bystander on IRC was able to reproduce the same problem using both the stable and nightly versions of rustc.
An Apology I wish I could narrow down the problem instead of just dumping this huge codebase on you, but I frankly am not sure how to even begin doing that.