Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Point macros 1.1 errors to the input item #6

Closed
wants to merge 2 commits into from

Conversation

dtolnay
Copy link

@dtolnay dtolnay commented Sep 2, 2016

Fixes rust-lang#36218.

Before:

error[E0106]: missing lifetime specifier
  --> src/main.rs:10:10
   |
10 | #[derive(Serialize, Deserialize)]
   |          ^ expected lifetime parameter

error[E0038]: the trait `T` cannot be made into an object
  --> src/main.rs:15:15
   |
15 | #[derive(Serialize, Deserialize)]
   |          ^^^^^^^^^^ the trait `T` cannot be made into an object

After:

error[E0106]: missing lifetime specifier
  --> src/main.rs:11:1
   |
11 | struct A {
   | ^ expected lifetime parameter

error[E0038]: the trait `T` cannot be made into an object
  --> src/main.rs:16:1
   |
16 | struct B<'a> {
   | ^ the trait `T` cannot be made into an object

alexcrichton and others added 2 commits September 1, 2016 22:33
This commit is an implementation of [RFC 1681] which adds support to the
compiler for first-class user-define custom `#[derive]` modes with a far more
stable API than plugins have today.

[RFC 1681]: https://github.com/rust-lang/rfcs/blob/master/text/1681-macros-1.1.md

The main features added by this commit are:

* A new `rustc-macro` crate-type. This crate type represents one which will
  provide custom `derive` implementations and perhaps eventually flower into the
  implementation of macros 2.0 as well.

* A new `rustc_macro` crate in the standard distribution. This crate will
  provide the runtime interface between macro crates and the compiler. The API
  here is particularly conservative right now but has quite a bit of room to
  expand into any manner of APIs required by macro authors.

* The ability to load new derive modes through the `#[macro_use]` annotations on
  other crates.

All support added here is gated behind the `rustc_macro` feature gate, both for
the library support (the `rustc_macro` crate) as well as the language features.

There are a few minor differences from the implementation outlined in the RFC,
such as the `rustc_macro` crate being available as a dylib and all symbols are
`dlsym`'d directly instead of having a shim compiled. These should only affect
the implementation, however, not the public interface.

This commit also ended up touching a lot of code related to `#[derive]`, making
a few notable changes:

* Recognized derive attributes are no longer desugared to `derive_Foo`. Wasn't
  sure how to keep this behavior and *not* expose it to custom derive.

* Derive attributes no longer have access to unstable features by default, they
  have to opt in on a granular level.

* The `derive(Copy,Clone)` optimization is now done through another "obscure
  attribute" which is just intended to ferry along in the compiler that such an
  optimization is possible. The `derive(PartialEq,Eq)` optimization was also
  updated to do something similar.

---

One part of this PR which needs to be improved before stabilizing are the errors
and exact interfaces here. The error messages are relatively poor quality and
there are surprising spects of this such as `#[derive(PartialEq, Eq, MyTrait)]`
not working by default. The custom attributes added by the compiler end up
becoming unstable again when going through a custom impl.

Hopefully though this is enough to start allowing experimentation on crates.io!

syntax-[breaking-change]
Before:

```rust
error[E0106]: missing lifetime specifier
  --> src/main.rs:10:10
   |
10 | #[derive(Serialize, Deserialize)]
   |          ^ expected lifetime parameter

error[E0038]: the trait `T` cannot be made into an object
  --> src/main.rs:15:15
   |
15 | #[derive(Serialize, Deserialize)]
   |          ^^^^^^^^^^ the trait `T` cannot be made into an object
```

After:

```rust
error[E0106]: missing lifetime specifier
  --> src/main.rs:11:1
   |
11 | struct A {
   | ^ expected lifetime parameter

error[E0038]: the trait `T` cannot be made into an object
  --> src/main.rs:16:1
   |
16 | struct B<'a> {
   | ^ the trait `T` cannot be made into an object
```
@alexcrichton
Copy link
Owner

Hm I'm hesitant to do this'll make some errors better but make others worse. I'm not quite sure where the defaults should go, however. Perhaps we could hold off on this until it's in tree?

@dtolnay
Copy link
Author

dtolnay commented Sep 2, 2016

Makes sense, let's hold off.

bors added a commit to rust-lang/rust that referenced this pull request Sep 11, 2016
Point macros 1.1 errors to the input item

Moved from alexcrichton#6 to continue discussion. Fixes #36218.

Before:

```rust
error[E0106]: missing lifetime specifier
  --> src/main.rs:10:10
   |
10 | #[derive(Serialize, Deserialize)]
   |          ^ expected lifetime parameter

error[E0038]: the trait `T` cannot be made into an object
  --> src/main.rs:15:15
   |
15 | #[derive(Serialize, Deserialize)]
   |          ^^^^^^^^^^ the trait `T` cannot be made into an object
```

After:

```rust
error[E0106]: missing lifetime specifier
  --> src/main.rs:11:1
   |
11 | struct A {
   | ^ expected lifetime parameter

error[E0038]: the trait `T` cannot be made into an object
  --> src/main.rs:16:1
   |
16 | struct B<'a> {
   | ^ the trait `T` cannot be made into an object
```
alexcrichton pushed a commit that referenced this pull request Dec 2, 2016
Add small-copy optimization for copy_from_slice

## Summary

During benchmarking, I found that one of my programs spent between 5 and 10 percent of the time doing memmoves. Ultimately I tracked these down to single-byte slices being copied with a memcopy. Doing a manual copy if the slice contains only one element can speed things up significantly. For my program, this reduced the running time by 20%.

## Background

I am optimizing a program that relies heavily on reading a single byte at a time. To avoid IO overhead, I read all data into a vector once, and then I use a `Cursor` around that vector to read from. During profiling, I noticed that `__memmove_avx_unaligned_erms` was hot, taking up 7.3% of the running time. It turns out that these were caused by calls to `Cursor::read()`, which calls `<&[u8] as Read>::read()`, which calls `&[T]::copy_from_slice()`, which calls `ptr::copy_nonoverlapping()`. This one is implemented as a memcopy. Copying a single byte with a memcopy is very wasteful, because (at least on my platform) it involves calling `memcpy` in libc. This is an indirect call when libc is linked dynamically, and furthermore `memcpy` is optimized for copying large amounts of data at the cost of a bit of overhead for small copies.

## Benchmarks

Before I made this change, `perf` reported the following for my program. I only included the relevant functions, and how they rank. (This is on a different machine than where I ran the original benchmarks. It has an older CPU, so `__memmove_sse2_unaligned_erms` is called instead of `__memmove_avx_unaligned_erms`.)

```
#3   5.47%  bench_decode  libc-2.24.so      [.] __memmove_sse2_unaligned_erms
#5   1.67%  bench_decode  libc-2.24.so      [.] memcpy@GLIBC_2.2.5
#6   1.51%  bench_decode  bench_decode      [.] memcpy@plt
```

`memcpy` is eating up 8.65% of the total running time, and the overhead of dispatching to a specialized fast copy function (`memcpy@GLIBC` showing up) is clearly visible. The price of dynamic linking (`memcpy@plt` showing up) is visible too.

After this change, this is what `perf` reports:

```
#5   0.33%  bench_decode  libc-2.24.so      [.] __memmove_sse2_unaligned_erms
rust-lang#14  0.01%  bench_decode  libc-2.24.so      [.] memcpy@GLIBC_2.2.5
```

Now only 0.34% of the running time is spent on memcopies. The dynamic linking overhead is not significant at all any more.

To add some more data, my program generates timing results for the operation in its main loop. These are the timings before and after the change:

| Time before   | Time after    | After/Before |
|---------------|---------------|--------------|
| 29.8 ± 0.8 ns | 23.6 ± 0.5 ns |  0.79 ± 0.03 |

The time is basically the total running time divided by a constant; the actual numbers are not important. This change reduced the total running time by 21% (much more than the original 9% spent on memmoves, likely because the CPU is stalling a lot less because data dependencies are more transparent). Of course YMMV and for most programs this will not matter at all. But when it does, the gains can be significant!

## Alternatives

* At first I implemented this in `io::Cursor`. I moved it to `&[T]::copy_from_slice()` instead, but this might be too intrusive, especially because it applies to all `T`, not just `u8`. To restrict this to `io::Read`, `<&[u8] as Read>::read()` is probably the best place.
* I tried copying bytes in a loop up to 64 or 8 bytes before calling `Read::read`, but both resulted in about a 20% slowdown instead of speedup.
alexcrichton pushed a commit that referenced this pull request Feb 12, 2017
LeakSanitizer, ThreadSanitizer, AddressSanitizer and MemorySanitizer support

```
$ cargo new --bin leak && cd $_

$ edit Cargo.toml && tail -n3 $_
```

``` toml
[profile.dev]
opt-level = 1
```

```
$ edit src/main.rs && cat $_
```

``` rust
use std::mem;

fn main() {
    let xs = vec![0, 1, 2, 3];
    mem::forget(xs);
}
```

```
$ RUSTFLAGS="-Z sanitizer=leak" cargo run --target x86_64-unknown-linux-gnu; echo $?
    Finished dev [optimized + debuginfo] target(s) in 0.0 secs
     Running `target/debug/leak`

=================================================================
==10848==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 16 byte(s) in 1 object(s) allocated from:
    #0 0x557c3488db1f in __interceptor_malloc /shared/rust/checkouts/lsan/src/compiler-rt/lib/lsan/lsan_interceptors.cc:55
    #1 0x557c34888aaa in alloc::heap::exchange_malloc::h68f3f8b376a0da42 /shared/rust/checkouts/lsan/src/liballoc/heap.rs:138
    #2 0x557c34888afc in leak::main::hc56ab767de6d653a $PWD/src/main.rs:4
    #3 0x557c348c0806 in __rust_maybe_catch_panic ($PWD/target/debug/leak+0x3d806)

SUMMARY: LeakSanitizer: 16 byte(s) leaked in 1 allocation(s).
23
```

```
$ cargo new --bin racy && cd $_

$ edit src/main.rs && cat $_
```

``` rust
use std::thread;

static mut ANSWER: i32 = 0;

fn main() {
    let t1 = thread::spawn(|| unsafe { ANSWER = 42 });
    unsafe {
        ANSWER = 24;
    }
    t1.join().ok();
}
```

```
$ RUSTFLAGS="-Z sanitizer=thread" cargo run --target x86_64-unknown-linux-gnu; echo $?
==================
WARNING: ThreadSanitizer: data race (pid=12019)
  Write of size 4 at 0x562105989bb4 by thread T1:
    #0 racy::main::_$u7b$$u7b$closure$u7d$$u7d$::hbe13ea9e8ac73f7e $PWD/src/main.rs:6 (racy+0x000000010e3f)
    #1 _$LT$std..panic..AssertUnwindSafe$LT$F$GT$$u20$as$u20$core..ops..FnOnce$LT$$LP$$RP$$GT$$GT$::call_once::h2e466a92accacc78 /shared/rust/checkouts/lsan/src/libstd/panic.rs:296 (racy+0x000000010cc5)
    #2 std::panicking::try::do_call::h7f4d2b38069e4042 /shared/rust/checkouts/lsan/src/libstd/panicking.rs:460 (racy+0x00000000c8f2)
    #3 __rust_maybe_catch_panic <null> (racy+0x0000000b4e56)
    #4 std::panic::catch_unwind::h31ca45621ad66d5a /shared/rust/checkouts/lsan/src/libstd/panic.rs:361 (racy+0x00000000b517)
    #5 std::thread::Builder::spawn::_$u7b$$u7b$closure$u7d$$u7d$::hccfc37175dea0b01 /shared/rust/checkouts/lsan/src/libstd/thread/mod.rs:357 (racy+0x00000000c226)
    #6 _$LT$F$u20$as$u20$alloc..boxed..FnBox$LT$A$GT$$GT$::call_box::hd880bbf91561e033 /shared/rust/checkouts/lsan/src/liballoc/boxed.rs:605 (racy+0x00000000f27e)
    #7 std::sys::imp::thread::Thread::new::thread_start::hebdfc4b3d17afc85 <null> (racy+0x0000000abd40)

  Previous write of size 4 at 0x562105989bb4 by main thread:
    #0 racy::main::h23e6e5ca46d085c3 $PWD/src/main.rs:8 (racy+0x000000010d7c)
    #1 __rust_maybe_catch_panic <null> (racy+0x0000000b4e56)
    #2 __libc_start_main <null> (libc.so.6+0x000000020290)

  Location is global 'racy::ANSWER::h543d2b139f819b19' of size 4 at 0x562105989bb4 (racy+0x0000002f8bb4)

  Thread T1 (tid=12028, running) created by main thread at:
    #0 pthread_create /shared/rust/checkouts/lsan/src/compiler-rt/lib/tsan/rtl/tsan_interceptors.cc:902 (racy+0x00000001aedb)
    #1 std::sys::imp::thread::Thread::new::hce44187bf4a36222 <null> (racy+0x0000000ab9ae)
    #2 std::thread::spawn::he382608373eb667e /shared/rust/checkouts/lsan/src/libstd/thread/mod.rs:412 (racy+0x00000000b5aa)
    #3 racy::main::h23e6e5ca46d085c3 $PWD/src/main.rs:6 (racy+0x000000010d5c)
    #4 __rust_maybe_catch_panic <null> (racy+0x0000000b4e56)
    #5 __libc_start_main <null> (libc.so.6+0x000000020290)

SUMMARY: ThreadSanitizer: data race $PWD/src/main.rs:6 in racy::main::_$u7b$$u7b$closure$u7d$$u7d$::hbe13ea9e8ac73f7e
==================
ThreadSanitizer: reported 1 warnings
66
```

```
$ cargo new --bin oob && cd $_

$ edit src/main.rs && cat $_
```

``` rust
fn main() {
    let xs = [0, 1, 2, 3];
    let y = unsafe { *xs.as_ptr().offset(4) };
}
```

```
$ RUSTFLAGS="-Z sanitizer=address" cargo run --target x86_64-unknown-linux-gnu; echo $?
=================================================================
==13328==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7fff29f3ecd0 at pc 0x55802dc6bf7e bp 0x7fff29f3ec90 sp 0x7fff29f3ec88
READ of size 4 at 0x7fff29f3ecd0 thread T0
    #0 0x55802dc6bf7d in oob::main::h0adc7b67e5feb2e7 $PWD/src/main.rs:3
    #1 0x55802dd60426 in __rust_maybe_catch_panic ($PWD/target/debug/oob+0xfe426)
    #2 0x55802dd58dd9 in std::rt::lang_start::hb2951fc8a59d62a7 ($PWD/target/debug/oob+0xf6dd9)
    #3 0x55802dc6c002 in main ($PWD/target/debug/oob+0xa002)
    #4 0x7fad8c3b3290 in __libc_start_main (/usr/lib/libc.so.6+0x20290)
    #5 0x55802dc6b719 in _start ($PWD/target/debug/oob+0x9719)

Address 0x7fff29f3ecd0 is located in stack of thread T0 at offset 48 in frame
    #0 0x55802dc6bd5f in oob::main::h0adc7b67e5feb2e7 $PWD/src/main.rs:1

  This frame has 1 object(s):
    [32, 48) 'xs' <== Memory access at offset 48 overflows this variable
HINT: this may be a false positive if your program uses some custom stack unwind mechanism or swapcontext
      (longjmp and C++ exceptions *are* supported)
SUMMARY: AddressSanitizer: stack-buffer-overflow $PWD/src/main.rs:3 in oob::main::h0adc7b67e5feb2e7
Shadow bytes around the buggy address:
  0x1000653dfd40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1000653dfd50: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1000653dfd60: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1000653dfd70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1000653dfd80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x1000653dfd90: 00 00 00 00 f1 f1 f1 f1 00 00[f3]f3 00 00 00 00
  0x1000653dfda0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1000653dfdb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1000653dfdc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1000653dfdd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1000653dfde0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07
  Heap left redzone:       fa
  Heap right redzone:      fb
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack partial redzone:   f4
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==13328==ABORTING
1
```

```
$ cargo new --bin uninit && cd $_

$ edit src/main.rs && cat $_
```

``` rust
use std::mem;

fn main() {
    let xs: [u8; 4] = unsafe { mem::uninitialized() };
    let y = xs[0] + xs[1];
}
```

```
$ RUSTFLAGS="-Z sanitizer=memory" cargo run; echo $?
==30198==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x563f4b6867da in uninit::main::hc2731cd4f2ed48f8 $PWD/src/main.rs:5
    #1 0x563f4b7033b6 in __rust_maybe_catch_panic ($PWD/target/debug/uninit+0x873b6)
    #2 0x563f4b6fbd69 in std::rt::lang_start::hb2951fc8a59d62a7 ($PWD/target/debug/uninit+0x7fd69)
    #3 0x563f4b6868a9 in main ($PWD/target/debug/uninit+0xa8a9)
    #4 0x7fe844354290 in __libc_start_main (/usr/lib/libc.so.6+0x20290)
    #5 0x563f4b6864f9 in _start ($PWD/target/debug/uninit+0xa4f9)

SUMMARY: MemorySanitizer: use-of-uninitialized-value $PWD/src/main.rs:5 in uninit::main::hc2731cd4f2ed48f8
Exiting
77
```
alexcrichton pushed a commit that referenced this pull request Sep 9, 2019
rebase code from rust-lang/rust master branch
alexcrichton pushed a commit that referenced this pull request Nov 30, 2020
Don't run `resolve_vars_if_possible` in `normalize_erasing_regions`

Neither `@eddyb` nor I could figure out what this was for. I changed it to `assert_eq!(normalized_value, infcx.resolve_vars_if_possible(&normalized_value));` and it passed the UI test suite.

<details><summary>

Outdated, I figured out the issue - `needs_infer()` needs to come _after_ erasing the lifetimes

</summary>

Strangely, if I change it to `assert!(!normalized_value.needs_infer())` it panics almost immediately:

```
query stack during panic:
#0 [normalize_generic_arg_after_erasing_regions] normalizing `<str::IsWhitespace as str::pattern::Pattern>::Searcher`
#1 [needs_drop_raw] computing whether `str::iter::Split<str::IsWhitespace>` needs drop
#2 [mir_built] building MIR for `str::<impl str>::split_whitespace`
#3 [unsafety_check_result] unsafety-checking `str::<impl str>::split_whitespace`
#4 [mir_const] processing MIR for `str::<impl str>::split_whitespace`
#5 [mir_promoted] processing `str::<impl str>::split_whitespace`
#6 [mir_borrowck] borrow-checking `str::<impl str>::split_whitespace`
#7 [analysis] running analysis passes on this crate
end of query stack
```

I'm not entirely sure what's going on - maybe the two disagree?

</details>

For context, this came up while reviewing rust-lang#77467 (cc `@lcnr).`

Possibly this needs a crater run?

r? `@nikomatsakis`
cc `@matthewjasper`
alexcrichton pushed a commit that referenced this pull request Jan 28, 2024
Change prefetch to avoid deadlock

Was abled to reproduce the deadlock in rust-lang#118205 and created a coredump when it happen. When looking at the backtraces  I noticed that the prefetch of exported_symbols (Thread 17 frame 4) started after the "actual" exported_symbols (Thread 2 frame 18) but it also is working on some of the collect_crate_mono_items (Thread 17 frame12 ) that Thread 2 is blocked on resulting in a deadlock.

This PR results in less parallell work that can be done at the same time but from what I can find we do not call the query exported_symbols from multiple places in the same join call any more.

```
Thread 17 (Thread 0x7f87b6299700 (LWP 11370)):
#0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007f87be5166a9 in <parking_lot::condvar::Condvar>::wait_until_internal () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
#2  0x00007f87be12d854 in <rustc_query_system::query::job::QueryLatch>::wait_on () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
#3  0x00007f87bd27d16f in rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::VecCache<rustc_span::def_id::CrateNum, rustc_middle::query::erase::Erased<[u8; 16]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
#4  0x00007f87bd0b5b6a in rustc_query_impl::query_impl::exported_symbols::get_query_non_incr::__rust_end_short_backtrace () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
#5  0x00007f87bdaebb0a in rustc_metadata::rmeta::encoder::encode_metadata::{closure#1}::{closure#1} () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
#6  0x00007f87bdae1509 in rayon_core::join::join_context::call_b::<core::option::Option<rustc_data_structures::marker::FromDyn<&[(rustc_middle::middle::exported_symbols::ExportedSymbol, rustc_middle::middle::exported_symbols::SymbolExportInfo)]>>, rayon_core::join::join::call<core::option::Option<rustc_data_structures::marker::FromDyn<&[(rustc_middle::middle::exported_symbols::ExportedSymbol, rustc_middle::middle::exported_symbols::SymbolExportInfo)]>>, rustc_data_structures::sync::parallel::enabled::join<rustc_metadata::rmeta::encoder::encode_metadata::{closure#1}::{closure#0}, rustc_metadata::rmeta::encoder::encode_metadata::{closure#1}::{closure#1}, (), &[(rustc_middle::middle::exported_symbols::ExportedSymbol, rustc_middle::middle::exported_symbols::SymbolExportInfo)]>::{closure#0}::{closure#1}>::{closure#0}>::{closure#0} () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
#7  0x00007f87bdae32ff in <rayon_core::job::StackJob<rayon_core::latch::SpinLatch, rayon_core::join::join_context::call_b<core::option::Option<rustc_data_structures::marker::FromDyn<&[(rustc_middle::middle::exported_symbols::ExportedSymbol, rustc_middle::middle::exported_symbols::SymbolExportInfo)]>>, rayon_core::join::join::call<core::option::Option<rustc_data_structures::marker::FromDyn<&[(rustc_middle::middle::exported_symbols::ExportedSymbol, rustc_middle::middle::exported_symbols::SymbolExportInfo)]>>, rustc_data_structures::sync::parallel::enabled::join<rustc_metadata::rmeta::encoder::encode_metadata::{closure#1}::{closure#0}, rustc_metadata::rmeta::encoder::encode_metadata::{closure#1}::{closure#1}, (), &[(rustc_middle::middle::exported_symbols::ExportedSymbol, rustc_middle::middle::exported_symbols::SymbolExportInfo)]>::{closure#0}::{closure#1}>::{closure#0}>::{closure#0}, core::option::Option<rustc_data_structures::marker::FromDyn<&[(rustc_middle::middle::exported_symbols::ExportedSymbol, rustc_middle::middle::exported_symbols::SymbolExportInfo)]>>> as rayon_core::job::Job>::execute () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
#8  0x00007f87b8338823 in <rayon_core::registry::WorkerThread>::wait_until_cold () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
#9  0x00007f87bc2edbaf in rayon_core::join::join_context::<rayon::iter::plumbing::bridge_producer_consumer::helper<rayon::vec::DrainProducer<rustc_middle::mir::mono::MonoItem>, rayon::iter::for_each::ForEachConsumer<rustc_data_structures::sync::parallel::enabled::par_for_each_in<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure#0}>::{closure#0}::{closure#0}>>::{closure#0}, rayon::iter::plumbing::bridge_producer_consumer::helper<rayon::vec::DrainProducer<rustc_middle::mir::mono::MonoItem>, rayon::iter::for_each::ForEachConsumer<rustc_data_structures::sync::parallel::enabled::par_for_each_in<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure#0}>::{closure#0}::{closure#0}>>::{closure#1}, (), ()>::{closure#0} () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#10 0x00007f87bc2ed313 in rayon_core::registry::in_worker::<rayon_core::join::join_context<rayon::iter::plumbing::bridge_producer_consumer::helper<rayon::vec::DrainProducer<rustc_middle::mir::mono::MonoItem>, rayon::iter::for_each::ForEachConsumer<rustc_data_structures::sync::parallel::enabled::par_for_each_in<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure#0}>::{closure#0}::{closure#0}>>::{closure#0}, rayon::iter::plumbing::bridge_producer_consumer::helper<rayon::vec::DrainProducer<rustc_middle::mir::mono::MonoItem>, rayon::iter::for_each::ForEachConsumer<rustc_data_structures::sync::parallel::enabled::par_for_each_in<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure#0}>::{closure#0}::{closure#0}>>::{closure#1}, (), ()>::{closure#0}, ((), ())> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#11 0x00007f87bc2db2a4 in rayon::iter::plumbing::bridge_producer_consumer::helper::<rayon::vec::DrainProducer<rustc_middle::mir::mono::MonoItem>, rayon::iter::for_each::ForEachConsumer<rustc_data_structures::sync::parallel::enabled::par_for_each_in<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure#0}>::{closure#0}::{closure#0}>> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#12 0x00007f87bc2eead2 in <rayon_core::job::StackJob<rayon_core::latch::SpinLatch, rayon_core::join::join_context::call_b<(), rayon::iter::plumbing::bridge_producer_consumer::helper<rayon::vec::DrainProducer<rustc_middle::mir::mono::MonoItem>, rayon::iter::for_each::ForEachConsumer<rustc_data_structures::sync::parallel::enabled::par_for_each_in<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure#0}>::{closure#0}::{closure#0}>>::{closure#1}>::{closure#0}, ()> as rayon_core::job::Job>::execute () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#13 0x00007f87b8338823 in <rayon_core::registry::WorkerThread>::wait_until_cold () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#14 0x00007f87be52d1f9 in <rayon_core::registry::ThreadBuilder>::run () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#15 0x00007f87b8461c57 in <scoped_tls::ScopedKey<rustc_span::SessionGlobals>>::set::<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#3}::{closure#0}::{closure#0}::{closure#0}, ()> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#16 0x00007f87b846e465 in rustc_span::set_session_globals_then::<(), rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#3}::{closure#0}::{closure#0}::{closure#0}> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#17 0x00007f87b844f282 in <<crossbeam_utils::thread::ScopedThreadBuilder>::spawn<<rayon_core::ThreadPoolBuilder>::build_scoped<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#3}::{closure#0}::{closure#0}, rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#3}::{closure#0}::{closure#1}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#0}::{closure#0}::{closure#0}, ()>::{closure#0} as core::ops::function::FnOnce<()>>::call_once::{shim:vtable#0} () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#18 0x00007f87b846af58 in <<std::thread::Builder>::spawn_unchecked_<alloc::boxed::Box<dyn core::ops::function::FnOnce<(), Output = ()> + core::marker::Send>, ()>::{closure#1} as core::ops::function::FnOnce<()>>::call_once::{shim:vtable#0} () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#19 0x00007f87b7898e85 in std::sys::unix::thread::Thread::new::thread_start () from /home/andjo403/.rustup/toolchains/stage1/lib/libstd-d570b0650d35d951.so
rust-lang#20 0x00007f87b7615609 in start_thread (arg=<optimized out>) at pthread_create.c:477
rust-lang#21 0x00007f87b7755133 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7f87b729b700 (LWP 11368)):
#0  syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1  0x00007f87b7887b51 in std::sys::unix::locks::futex_condvar::Condvar::wait () from /home/andjo403/.rustup/toolchains/stage1/lib/libstd-d570b0650d35d951.so
#2  0x00007f87b8339478 in <rayon_core::sleep::Sleep>::sleep () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
#3  0x00007f87b83387c3 in <rayon_core::registry::WorkerThread>::wait_until_cold () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
#4  0x00007f87bc2edbaf in rayon_core::join::join_context::<rayon::iter::plumbing::bridge_producer_consumer::helper<rayon::vec::DrainProducer<rustc_middle::mir::mono::MonoItem>, rayon::iter::for_each::ForEachConsumer<rustc_data_structures::sync::parallel::enabled::par_for_each_in<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure#0}>::{closure#0}::{closure#0}>>::{closure#0}, rayon::iter::plumbing::bridge_producer_consumer::helper<rayon::vec::DrainProducer<rustc_middle::mir::mono::MonoItem>, rayon::iter::for_each::ForEachConsumer<rustc_data_structures::sync::parallel::enabled::par_for_each_in<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure#0}>::{closure#0}::{closure#0}>>::{closure#1}, (), ()>::{closure#0} () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
#5  0x00007f87bc2ed313 in rayon_core::registry::in_worker::<rayon_core::join::join_context<rayon::iter::plumbing::bridge_producer_consumer::helper<rayon::vec::DrainProducer<rustc_middle::mir::mono::MonoItem>, rayon::iter::for_each::ForEachConsumer<rustc_data_structures::sync::parallel::enabled::par_for_each_in<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure#0}>::{closure#0}::{closure#0}>>::{closure#0}, rayon::iter::plumbing::bridge_producer_consumer::helper<rayon::vec::DrainProducer<rustc_middle::mir::mono::MonoItem>, rayon::iter::for_each::ForEachConsumer<rustc_data_structures::sync::parallel::enabled::par_for_each_in<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure#0}>::{closure#0}::{closure#0}>>::{closure#1}, (), ()>::{closure#0}, ((), ())> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
#6  0x00007f87bc2db50c in <rayon::vec::IntoIter<rustc_middle::mir::mono::MonoItem> as rayon::iter::ParallelIterator>::for_each::<rustc_data_structures::sync::parallel::enabled::par_for_each_in<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure#0}>::{closure#0}::{closure#0}> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
#7  0x00007f87bc2e8cd7 in <rustc_session::session::Session>::time::<(), rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
#8  0x00007f87bc2b8f2c in rustc_monomorphize::collector::collect_crate_mono_items () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
#9  0x00007f87bc2c30d9 in rustc_monomorphize::partitioning::collect_and_partition_mono_items () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#10 0x00007f87bcf2cde6 in rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::collect_and_partition_mono_items::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 24]>> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#11 0x00007f87bd156a3c in <rustc_query_impl::query_impl::collect_and_partition_mono_items::dynamic_query::{closure#2} as core::ops::function::FnOnce<(rustc_middle::ty::context::TyCtxt, ())>>::call_once () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#12 0x00007f87bd1c6a7d in rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::SingleCache<rustc_middle::query::erase::Erased<[u8; 24]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#13 0x00007f87bd15df40 in rustc_query_impl::query_impl::collect_and_partition_mono_items::get_query_non_incr::__rust_end_short_backtrace () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#14 0x00007f87bd7a0ad9 in rustc_codegen_ssa::back::symbol_export::exported_symbols_provider_local () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#15 0x00007f87bcf29acb in rustc_query_impl::plumbing::__rust_begin_short_backtrace::<rustc_query_impl::query_impl::exported_symbols::dynamic_query::{closure#2}::{closure#0}, rustc_middle::query::erase::Erased<[u8; 16]>> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#16 0x00007f87bcfdb350 in <rustc_query_impl::query_impl::exported_symbols::dynamic_query::{closure#2} as core::ops::function::FnOnce<(rustc_middle::ty::context::TyCtxt, rustc_span::def_id::CrateNum)>>::call_once () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#17 0x00007f87bd27d64f in rustc_query_system::query::plumbing::try_execute_query::<rustc_query_impl::DynamicConfig<rustc_query_system::query::caches::VecCache<rustc_span::def_id::CrateNum, rustc_middle::query::erase::Erased<[u8; 16]>>, false, false, false>, rustc_query_impl::plumbing::QueryCtxt, false> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#18 0x00007f87bd0b5b6a in rustc_query_impl::query_impl::exported_symbols::get_query_non_incr::__rust_end_short_backtrace () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#19 0x00007f87bda927ce in rustc_middle::query::plumbing::query_get_at::<rustc_query_system::query::caches::VecCache<rustc_span::def_id::CrateNum, rustc_middle::query::erase::Erased<[u8; 16]>>> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#20 0x00007f87bda9c93f in <rustc_metadata::rmeta::encoder::EncodeContext>::encode_crate_root () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#21 0x00007f87bdaa6ef7 in rustc_metadata::rmeta::encoder::encode_metadata_impl () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#22 0x00007f87bdae0b77 in rayon_core::join::join_context::<rayon_core::join::join::call<core::option::Option<rustc_data_structures::marker::FromDyn<()>>, rustc_data_structures::sync::parallel::enabled::join<rustc_metadata::rmeta::encoder::encode_metadata::{closure#0}, rustc_metadata::rmeta::encoder::encode_metadata::{closure#1}, (), ()>::{closure#0}::{closure#0}>::{closure#0}, rayon_core::join::join::call<core::option::Option<rustc_data_structures::marker::FromDyn<()>>, rustc_data_structures::sync::parallel::enabled::join<rustc_metadata::rmeta::encoder::encode_metadata::{closure#0}, rustc_metadata::rmeta::encoder::encode_metadata::{closure#1}, (), ()>::{closure#0}::{closure#1}>::{closure#0}, core::option::Option<rustc_data_structures::marker::FromDyn<()>>, core::option::Option<rustc_data_structures::marker::FromDyn<()>>>::{closure#0} () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#23 0x00007f87bdaded2f in rayon_core::registry::in_worker::<rayon_core::join::join_context<rayon_core::join::join::call<core::option::Option<rustc_data_structures::marker::FromDyn<()>>, rustc_data_structures::sync::parallel::enabled::join<rustc_metadata::rmeta::encoder::encode_metadata::{closure#0}, rustc_metadata::rmeta::encoder::encode_metadata::{closure#1}, (), ()>::{closure#0}::{closure#0}>::{closure#0}, rayon_core::join::join::call<core::option::Option<rustc_data_structures::marker::FromDyn<()>>, rustc_data_structures::sync::parallel::enabled::join<rustc_metadata::rmeta::encoder::encode_metadata::{closure#0}, rustc_metadata::rmeta::encoder::encode_metadata::{closure#1}, (), ()>::{closure#0}::{closure#1}>::{closure#0}, core::option::Option<rustc_data_structures::marker::FromDyn<()>>, core::option::Option<rustc_data_structures::marker::FromDyn<()>>>::{closure#0}, (core::option::Option<rustc_data_structures::marker::FromDyn<()>>, core::option::Option<rustc_data_structures::marker::FromDyn<()>>)> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#24 0x00007f87bdaa5a03 in rustc_metadata::rmeta::encoder::encode_metadata () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#25 0x00007f87bdaed628 in rustc_metadata::fs::encode_and_write_metadata () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#26 0x00007f87b86608be in rustc_interface::passes::start_codegen () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#27 0x00007f87b8664946 in <rustc_middle::ty::context::GlobalCtxt>::enter::<<rustc_interface::queries::Queries>::codegen_and_build_linker::{closure#0}, core::result::Result<rustc_interface::queries::Linker, rustc_span::ErrorGuaranteed>> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#28 0x00007f87b864db00 in <rustc_interface::queries::Queries>::codegen_and_build_linker () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#29 0x00007f87b849400f in <rustc_interface::interface::Compiler>::enter::<rustc_driver_impl::run_compiler::{closure#0}::{closure#0}, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#30 0x00007f87b846e067 in rustc_span::set_source_map::<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}::{closure#0}> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#31 0x00007f87b844dc13 in <rayon_core::thread_pool::ThreadPool>::install::<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#0} () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#32 0x00007f87b84509a1 in <rayon_core::job::StackJob<rayon_core::latch::LatchRef<rayon_core::latch::LockLatch>, <rayon_core::registry::Registry>::in_worker_cold<<rayon_core::thread_pool::ThreadPool>::install<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#0}::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>> as rayon_core::job::Job>::execute () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#33 0x00007f87b8338823 in <rayon_core::registry::WorkerThread>::wait_until_cold () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#34 0x00007f87be52d1f9 in <rayon_core::registry::ThreadBuilder>::run () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#35 0x00007f87b8461c57 in <scoped_tls::ScopedKey<rustc_span::SessionGlobals>>::set::<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#3}::{closure#0}::{closure#0}::{closure#0}, ()> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#36 0x00007f87b846e465 in rustc_span::set_session_globals_then::<(), rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#3}::{closure#0}::{closure#0}::{closure#0}> () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#37 0x00007f87b844f282 in <<crossbeam_utils::thread::ScopedThreadBuilder>::spawn<<rayon_core::ThreadPoolBuilder>::build_scoped<rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#3}::{closure#0}::{closure#0}, rustc_interface::util::run_in_thread_pool_with_globals<rustc_interface::interface::run_compiler<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#0}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#3}::{closure#0}::{closure#1}, core::result::Result<(), rustc_span::ErrorGuaranteed>>::{closure#0}::{closure#0}::{closure#0}, ()>::{closure#0} as core::ops::function::FnOnce<()>>::call_once::{shim:vtable#0} () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#38 0x00007f87b846af58 in <<std::thread::Builder>::spawn_unchecked_<alloc::boxed::Box<dyn core::ops::function::FnOnce<(), Output = ()> + core::marker::Send>, ()>::{closure#1} as core::ops::function::FnOnce<()>>::call_once::{shim:vtable#0} () from /home/andjo403/.rustup/toolchains/stage1/lib/librustc_driver-70ddb84e8f7ce707.so
rust-lang#39 0x00007f87b7898e85 in std::sys::unix::thread::Thread::new::thread_start () from /home/andjo403/.rustup/toolchains/stage1/lib/libstd-d570b0650d35d951.so
rust-lang#40 0x00007f87b7615609 in start_thread (arg=<optimized out>) at pthread_create.c:477
rust-lang#41 0x00007f87b7755133 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

```

fixes rust-lang#118205
fixes rust-lang#117759 from the latest logs it is the same query map as in rust-lang#118205
fixes rust-lang#118529
fixes rust-lang#117784
cc rust-lang#118206

r? `@SparrowLii`
alexcrichton pushed a commit that referenced this pull request Oct 23, 2024
…raheemdev

Optimize `Box::default` and `Arc::default` to construct more types in place

Both the `Arc` and `Box` `Default` impls currently call `T::default()` before allocating, and then moving the resulting `T` into the allocation.

Most `Default` impls are trivial, which should in theory allow
LLVM to construct `T: Default` directly in the `Box` allocation when calling
`<Box<T>>::default()`.

However, the allocation may fail, which necessitates calling `T`'s destructor if it has one.
If the destructor is non-trivial, then LLVM has a hard time proving that it's
sound to elide, which makes it construct `T` on the stack first, and then copy it into the allocation.

Change both of these impls to allocate first, and then call `T::default` into the uninitialized allocation, so that LLVM doesn't have to prove that it's sound to elide the destructor/initial stack copy.

For example, given the following Rust code:

```rust
#[derive(Default, Clone)]
struct Foo {
    x: Vec<u8>,
    z: String,
    y: Vec<u8>,
}

#[no_mangle]
pub fn src() -> Box<Foo> {
    Box::default()
}
```

<details open>
<summary>Before this PR:</summary>

```llvm
`@__rust_no_alloc_shim_is_unstable` = external global i8

; drop_in_place() generated in case the allocation fails

; core::ptr::drop_in_place<playground::Foo>
; Function Attrs: nounwind nonlazybind uwtable
define internal fastcc void `@"_ZN4core3ptr36drop_in_place$LT$playground..Foo$GT$17hff376aece491233bE"(ptr` noalias nocapture noundef readonly align 8 dereferenceable(72) %_1) unnamed_addr #0 personality ptr `@rust_eh_personality` {
start:
  %_1.val = load i64, ptr %_1, align 8
  %0 = icmp eq i64 %_1.val, 0
  br i1 %0, label %bb6, label %"_ZN63_$LT$alloc..alloc..Global$u20$as$u20$core..alloc..Allocator$GT$10deallocate17heaa87468709346b1E.exit.i.i.i4.i"

"_ZN63_$LT$alloc..alloc..Global$u20$as$u20$core..alloc..Allocator$GT$10deallocate17heaa87468709346b1E.exit.i.i.i4.i": ; preds = %start
  %1 = getelementptr inbounds i8, ptr %_1, i64 8
  %_1.val6 = load ptr, ptr %1, align 8, !nonnull !3, !noundef !3
  tail call void `@__rust_dealloc(ptr` noundef nonnull %_1.val6, i64 noundef %_1.val, i64 noundef 1) #8
  br label %bb6

bb6:                                              ; preds = %"_ZN63_$LT$alloc..alloc..Global$u20$as$u20$core..alloc..Allocator$GT$10deallocate17heaa87468709346b1E.exit.i.i.i4.i", %start
  %2 = getelementptr inbounds i8, ptr %_1, i64 24
  %.val9 = load i64, ptr %2, align 8
  %3 = icmp eq i64 %.val9, 0
  br i1 %3, label %bb5, label %"_ZN63_$LT$alloc..alloc..Global$u20$as$u20$core..alloc..Allocator$GT$10deallocate17heaa87468709346b1E.exit.i.i.i4.i.i11"

"_ZN63_$LT$alloc..alloc..Global$u20$as$u20$core..alloc..Allocator$GT$10deallocate17heaa87468709346b1E.exit.i.i.i4.i.i11": ; preds = %bb6
  %4 = getelementptr inbounds i8, ptr %_1, i64 32
  %.val10 = load ptr, ptr %4, align 8, !nonnull !3, !noundef !3
  tail call void `@__rust_dealloc(ptr` noundef nonnull %.val10, i64 noundef %.val9, i64 noundef 1) #8
  br label %bb5

bb5:                                              ; preds = %"_ZN63_$LT$alloc..alloc..Global$u20$as$u20$core..alloc..Allocator$GT$10deallocate17heaa87468709346b1E.exit.i.i.i4.i.i11", %bb6
  %5 = getelementptr inbounds i8, ptr %_1, i64 48
  %.val4 = load i64, ptr %5, align 8
  %6 = icmp eq i64 %.val4, 0
  br i1 %6, label %"_ZN4core3ptr46drop_in_place$LT$alloc..vec..Vec$LT$u8$GT$$GT$17hb5ca95423e113cf7E.exit16", label %"_ZN63_$LT$alloc..alloc..Global$u20$as$u20$core..alloc..Allocator$GT$10deallocate17heaa87468709346b1E.exit.i.i.i4.i15"

"_ZN63_$LT$alloc..alloc..Global$u20$as$u20$core..alloc..Allocator$GT$10deallocate17heaa87468709346b1E.exit.i.i.i4.i15": ; preds = %bb5
  %7 = getelementptr inbounds i8, ptr %_1, i64 56
  %.val5 = load ptr, ptr %7, align 8, !nonnull !3, !noundef !3
  tail call void `@__rust_dealloc(ptr` noundef nonnull %.val5, i64 noundef %.val4, i64 noundef 1) #8
  br label %"_ZN4core3ptr46drop_in_place$LT$alloc..vec..Vec$LT$u8$GT$$GT$17hb5ca95423e113cf7E.exit16"

"_ZN4core3ptr46drop_in_place$LT$alloc..vec..Vec$LT$u8$GT$$GT$17hb5ca95423e113cf7E.exit16": ; preds = %bb5, %"_ZN63_$LT$alloc..alloc..Global$u20$as$u20$core..alloc..Allocator$GT$10deallocate17heaa87468709346b1E.exit.i.i.i4.i15"
  ret void
}

; Function Attrs: nonlazybind uwtable
define noalias noundef nonnull align 8 ptr `@src()` unnamed_addr #1 personality ptr `@rust_eh_personality` {
start:

; alloca to place `Foo` in.
  %_1 = alloca [72 x i8], align 8
  call void `@llvm.lifetime.start.p0(i64` 72, ptr nonnull %_1)
  store i64 0, ptr %_1, align 8
  %_2.sroa.4.0._1.sroa_idx = getelementptr inbounds i8, ptr %_1, i64 8
  store ptr inttoptr (i64 1 to ptr), ptr %_2.sroa.4.0._1.sroa_idx, align 8
  %_2.sroa.5.0._1.sroa_idx = getelementptr inbounds i8, ptr %_1, i64 16
  %_3.sroa.4.0..sroa_idx = getelementptr inbounds i8, ptr %_1, i64 32
  call void `@llvm.memset.p0.i64(ptr` noundef nonnull align 8 dereferenceable(16) %_2.sroa.5.0._1.sroa_idx, i8 0, i64 16, i1 false)
  store ptr inttoptr (i64 1 to ptr), ptr %_3.sroa.4.0..sroa_idx, align 8
  %_3.sroa.5.0..sroa_idx = getelementptr inbounds i8, ptr %_1, i64 40
  %_4.sroa.4.0..sroa_idx = getelementptr inbounds i8, ptr %_1, i64 56
  call void `@llvm.memset.p0.i64(ptr` noundef nonnull align 8 dereferenceable(16) %_3.sroa.5.0..sroa_idx, i8 0, i64 16, i1 false)
  store ptr inttoptr (i64 1 to ptr), ptr %_4.sroa.4.0..sroa_idx, align 8
  %_4.sroa.5.0..sroa_idx = getelementptr inbounds i8, ptr %_1, i64 64
  store i64 0, ptr %_4.sroa.5.0..sroa_idx, align 8
  %0 = load volatile i8, ptr `@__rust_no_alloc_shim_is_unstable,` align 1, !noalias !4
  %_0.i.i.i = tail call noalias noundef align 8 dereferenceable_or_null(72) ptr `@__rust_alloc(i64` noundef 72, i64 noundef 8) #8, !noalias !4
  %1 = icmp eq ptr %_0.i.i.i, null
  br i1 %1, label %bb2.i, label %"_ZN5alloc5boxed12Box$LT$T$GT$3new17h0864de14f863a27aE.exit"

bb2.i:                                            ; preds = %start
; invoke alloc::alloc::handle_alloc_error
  invoke void `@_ZN5alloc5alloc18handle_alloc_error17h98142d0d8d74161bE(i64` noundef 8, i64 noundef 72) #9
          to label %.noexc unwind label %cleanup.i

.noexc:                                           ; preds = %bb2.i
  unreachable

cleanup.i:                                        ; preds = %bb2.i
  %2 = landingpad { ptr, i32 }
          cleanup
; call core::ptr::drop_in_place<playground::Foo>
  call fastcc void `@"_ZN4core3ptr36drop_in_place$LT$playground..Foo$GT$17hff376aece491233bE"(ptr` noalias noundef nonnull align 8 dereferenceable(72) %_1) rust-lang#10
  resume { ptr, i32 } %2

"_ZN5alloc5boxed12Box$LT$T$GT$3new17h0864de14f863a27aE.exit": ; preds = %start

; Copy from stack to heap if allocation is successful
  call void `@llvm.memcpy.p0.p0.i64(ptr` noundef nonnull align 8 dereferenceable(72) %_0.i.i.i, ptr noundef nonnull align 8 dereferenceable(72) %_1, i64 72, i1 false)
  call void `@llvm.lifetime.end.p0(i64` 72, ptr nonnull %_1)
  ret ptr %_0.i.i.i
}

```
</details>

<details>
<summary>After this PR</summary>

```llvm
; Notice how there's no `drop_in_place()` generated as well

define noalias noundef nonnull align 8 ptr `@src()` unnamed_addr #0 personality ptr `@rust_eh_personality` {
start:
; no stack allocation

  %0 = load volatile i8, ptr `@__rust_no_alloc_shim_is_unstable,` align 1
  %_0.i.i.i.i.i = tail call noalias noundef align 8 dereferenceable_or_null(72) ptr `@__rust_alloc(i64` noundef 72, i64 noundef 8) #5
  %1 = icmp eq ptr %_0.i.i.i.i.i, null
  br i1 %1, label %bb3.i, label %"_ZN5alloc5boxed16Box$LT$T$C$A$GT$13new_uninit_in17h80d6355ef4b73ea3E.exit"

bb3.i:                                            ; preds = %start
; call alloc::alloc::handle_alloc_error
  tail call void `@_ZN5alloc5alloc18handle_alloc_error17h98142d0d8d74161bE(i64` noundef 8, i64 noundef 72) #6
  unreachable

"_ZN5alloc5boxed16Box$LT$T$C$A$GT$13new_uninit_in17h80d6355ef4b73ea3E.exit": ; preds = %start
; construct `Foo` directly into the allocation if successful

  store i64 0, ptr %_0.i.i.i.i.i, align 8
  %_8.sroa.4.0._1.sroa_idx = getelementptr inbounds i8, ptr %_0.i.i.i.i.i, i64 8
  store ptr inttoptr (i64 1 to ptr), ptr %_8.sroa.4.0._1.sroa_idx, align 8
  %_8.sroa.5.0._1.sroa_idx = getelementptr inbounds i8, ptr %_0.i.i.i.i.i, i64 16
  %_8.sroa.7.0._1.sroa_idx = getelementptr inbounds i8, ptr %_0.i.i.i.i.i, i64 32
  tail call void `@llvm.memset.p0.i64(ptr` noundef nonnull align 8 dereferenceable(16) %_8.sroa.5.0._1.sroa_idx, i8 0, i64 16, i1 false)
  store ptr inttoptr (i64 1 to ptr), ptr %_8.sroa.7.0._1.sroa_idx, align 8
  %_8.sroa.8.0._1.sroa_idx = getelementptr inbounds i8, ptr %_0.i.i.i.i.i, i64 40
  %_8.sroa.10.0._1.sroa_idx = getelementptr inbounds i8, ptr %_0.i.i.i.i.i, i64 56
  tail call void `@llvm.memset.p0.i64(ptr` noundef nonnull align 8 dereferenceable(16) %_8.sroa.8.0._1.sroa_idx, i8 0, i64 16, i1 false)
  store ptr inttoptr (i64 1 to ptr), ptr %_8.sroa.10.0._1.sroa_idx, align 8
  %_8.sroa.11.0._1.sroa_idx = getelementptr inbounds i8, ptr %_0.i.i.i.i.i, i64 64
  store i64 0, ptr %_8.sroa.11.0._1.sroa_idx, align 8
  ret ptr %_0.i.i.i.i.i
}
```

</details>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

Successfully merging this pull request may close these issues.

2 participants