Startup objects disappearing from sysroot
When launching tests with --keep-stage option, startup objects such as rsbegin.o an rsend.o may disappear from the corresponding stageN compiler.
Fix issue #120784
Fix `ErrorGuaranteed` unsoundness with stash/steal.
When you stash an error, the error count is incremented. You can then use the non-zero error count to get an `ErrorGuaranteed`. You can then steal the error, which decrements the error count. You can then cancel the error.
Example code:
```
fn unsound(dcx: &DiagCtxt) -> ErrorGuaranteed {
let sp = rustc_span::DUMMY_SP;
let k = rustc_errors::StashKey::Cycle;
dcx.struct_err("bogus").stash(sp, k); // increment error count on stash
let guar = dcx.has_errors().unwrap(); // ErrorGuaranteed from error count > 0
let err = dcx.steal_diagnostic(sp, k).unwrap(); // decrement error count on steal
err.cancel(); // cancel error
guar // ErrorGuaranteed with no error emitted!
}
```
This commit fixes the problem in the simplest way: by not counting stashed errors in `DiagCtxt::{err_count,has_errors}`.
However, just doing this without any other changes leads to over 40 ui test failures. Mostly because of uninteresting extra errors (many saying "type annotations needed" when type inference fails), and in a few cases, due to delayed bugs causing ICEs when no normal errors are printed.
To fix these, this commit adds `DiagCtxt::stashed_err_count`, and uses it in three places alongside `DiagCtxt::{has_errors,err_count}`. It's dodgy to rely on it, because unlike `DiagCtxt::err_count` it can go up and down. But it's needed to preserve existing behaviour, and at least the three places that need it are now obvious.
r? oli-obk
Fix more `ty::Error` ICEs in MIR passes
Fixes#120791 - Add a check for `ty::Error` in the `ByMove` coroutine pass
Fixes#120816 - Add a check for `ty::Error` in the MIR validator
Also a drive-by fix for a FIXME I had asked oli to add
r? oli-obk
A drive-by rewrite of `give_region_a_name()`
This drive-by rewrite makes the cache-updating nature of the method clearer, using the Entry API into the hash table for region names to capture the update-insert nature of the method. May be marginally more efficient since it only runtime-borrows and indexes the map once, but in this context the performance impact is almost certainly completely negligible.
Note that this commit should preserve all externally visible behaviour. Notably, it preserves the debug logging:
1. printing even in the case of a `None` for the new computed name, and
2. only printing on new values, begin silent on reused values
Invert diagnostic lints.
That is, change `diagnostic_outside_of_impl` and `untranslatable_diagnostic` from `allow` to `deny`, because more than half of the compiler has been converted to use translated diagnostics.
This commit removes more `deny` attributes than it adds `allow` attributes, which proves that this change is warranted.
r? ````@davidtwco````
core/time: avoid divisions in Duration::new
In our (decently large) code base, we use `SystemTime::UNIX_EPOCH.elapsed()` in a lot of places & often in a loop or in the hot path. On [Unix](https://github.com/rust-lang/rust/blob/1.75.0/library/std/src/sys/unix/time.rs#L153-L162) at least, it seems we do calculations before hand to ensure that nanos is within the valid range, yet `Duration::new()` still checks it again, using 2 divisions. It seems like adding a branch can make this function 33% faster on ARM64 in the cases where nanos is already in the valid range & seems to have no effect in the other case.
Benchmarks:
M1 Pro (14-inch base model):
```
duration/current/checked
time: [1.5945 ns 1.6167 ns 1.6407 ns]
Found 5 outliers among 100 measurements (5.00%)
2 (2.00%) high mild
3 (3.00%) high severe
duration/current/unchecked
time: [1.5941 ns 1.6051 ns 1.6179 ns]
Found 2 outliers among 100 measurements (2.00%)
1 (1.00%) high mild
1 (1.00%) high severe
duration/branched/checked
time: [1.1997 ns 1.2048 ns 1.2104 ns]
Found 8 outliers among 100 measurements (8.00%)
4 (4.00%) high mild
4 (4.00%) high severe
duration/branched/unchecked
time: [1.5881 ns 1.5957 ns 1.6039 ns]
Found 6 outliers among 100 measurements (6.00%)
3 (3.00%) high mild
3 (3.00%) high severe
```
EC2 c7gd.16xlarge (Graviton 3):
```
duration/current/checked
time: [2.7996 ns 2.8000 ns 2.8003 ns]
Found 5 outliers among 100 measurements (5.00%)
2 (2.00%) low severe
3 (3.00%) low mild
duration/current/unchecked
time: [2.9922 ns 2.9925 ns 2.9928 ns]
Found 7 outliers among 100 measurements (7.00%)
4 (4.00%) low severe
1 (1.00%) low mild
2 (2.00%) high mild
duration/branched/checked
time: [2.0830 ns 2.0843 ns 2.0857 ns]
Found 3 outliers among 100 measurements (3.00%)
1 (1.00%) low severe
1 (1.00%) low mild
1 (1.00%) high mild
duration/branched/unchecked
time: [2.9879 ns 2.9886 ns 2.9893 ns]
Found 5 outliers among 100 measurements (5.00%)
3 (3.00%) low severe
2 (2.00%) low mild
```
EC2 r7iz.16xlarge (Intel Xeon Scalable-based (Sapphire Rapids)):
```
duration/current/checked
time: [980.60 ps 980.79 ps 980.99 ps]
Found 10 outliers among 100 measurements (10.00%)
4 (4.00%) low severe
2 (2.00%) low mild
3 (3.00%) high mild
1 (1.00%) high severe
duration/current/unchecked
time: [979.53 ps 979.74 ps 979.96 ps]
Found 6 outliers among 100 measurements (6.00%)
2 (2.00%) low severe
1 (1.00%) low mild
2 (2.00%) high mild
1 (1.00%) high severe
duration/branched/checked
time: [938.72 ps 938.96 ps 939.22 ps]
Found 4 outliers among 100 measurements (4.00%)
1 (1.00%) low mild
1 (1.00%) high mild
2 (2.00%) high severe
duration/branched/unchecked
time: [1.0103 ns 1.0110 ns 1.0118 ns]
Found 10 outliers among 100 measurements (10.00%)
2 (2.00%) low mild
7 (7.00%) high mild
1 (1.00%) high severe
```
Bench code (ran using stable 1.75.0 & criterion latest 0.5.1):
I couldn't find any benches for `Duration` in this repo, so I just copied the relevant types & recreated it.
```rust
use criterion::{black_box, criterion_group, criterion_main, Criterion};
pub fn duration_bench(c: &mut Criterion) {
const NANOS_PER_SEC: u32 = 1_000_000_000;
#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
#[repr(transparent)]
struct Nanoseconds(u32);
impl Default for Nanoseconds {
#[inline]
fn default() -> Self {
// SAFETY: 0 is within the valid range
unsafe { Nanoseconds(0) }
}
}
#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
pub struct Duration {
secs: u64,
nanos: Nanoseconds, // Always 0 <= nanos < NANOS_PER_SEC
}
impl Duration {
#[inline]
pub const fn new_current(secs: u64, nanos: u32) -> Duration {
let secs = match secs.checked_add((nanos / NANOS_PER_SEC) as u64) {
Some(secs) => secs,
None => panic!("overflow in Duration::new"),
};
let nanos = nanos % NANOS_PER_SEC;
// SAFETY: nanos % NANOS_PER_SEC < NANOS_PER_SEC, therefore nanos is within the valid range
Duration { secs, nanos: unsafe { Nanoseconds(nanos) } }
}
#[inline]
pub const fn new_branched(secs: u64, nanos: u32) -> Duration {
if nanos < NANOS_PER_SEC {
// SAFETY: nanos < NANOS_PER_SEC, therefore nanos is within the valid range
Duration { secs, nanos: unsafe { Nanoseconds(nanos) } }
} else {
let secs = match secs.checked_add((nanos / NANOS_PER_SEC) as u64) {
Some(secs) => secs,
None => panic!("overflow in Duration::new"),
};
let nanos = nanos % NANOS_PER_SEC;
// SAFETY: nanos % NANOS_PER_SEC < NANOS_PER_SEC, therefore nanos is within the valid range
Duration { secs, nanos: unsafe { Nanoseconds(nanos) } }
}
}
}
let mut group = c.benchmark_group("duration/current");
group.bench_function("checked", |b| {
b.iter(|| black_box(Duration::new_current(black_box(1_000_000_000), black_box(1_000_000))));
});
group.bench_function("unchecked", |b| {
b.iter(|| {
black_box(Duration::new_current(black_box(1_000_000_000), black_box(2_000_000_000)))
});
});
drop(group);
let mut group = c.benchmark_group("duration/branched");
group.bench_function("checked", |b| {
b.iter(|| {
black_box(Duration::new_branched(black_box(1_000_000_000), black_box(1_000_000)))
});
});
group.bench_function("unchecked", |b| {
b.iter(|| {
black_box(Duration::new_branched(black_box(1_000_000_000), black_box(2_000_000_000)))
});
});
}
criterion_group!(duration_benches, duration_bench);
criterion_main!(duration_benches);
```
Make privacy visitor use types more (instead of HIR)
r? ``@petrochenkov``
This is a prerequisite to normalizing projections, as otherwise we have too many invalid bound vars (hir_ty_to_ty is creating types that have bound vars, but no binder).
The commits are still chaotic, I'm gonna clean them up, but I just wanted to let you know about the general direction and wondering if we could land this before adding normalization, as normalization is where behavioral changes happen, and I'd like to keep that part as minimal as possible.
[context can be found on zulip](https://rust-lang.zulipchat.com/#narrow/stream/315482-t-compiler.2Fetc.2Fopaque-types/topic/weak.20type.20aliases.20and.20privacy)
Toggle assert_unsafe_precondition in codegen instead of expansion
The goal of this PR is to make some of the unsafe precondition checks in the standard library available in debug builds. Some UI tests are included to verify that it does that.
The diff is large, but most of it is blessing mir-opt tests and I've also split up this PR so it can be reviewed commit-by-commit.
This PR:
1. Adds a new intrinsic, `debug_assertions` which is lowered to a new MIR NullOp, and only to a constant after monomorphization
2. Rewrites `assume_unsafe_precondition` to check the new intrinsic, and be monomorphic.
3. Skips codegen of the `assume` intrinsic in unoptimized builds, because that was silly before but with these checks it's *very* silly
4. The checks with the most overhead are `ptr::read`/`ptr::write` and `NonNull::new_unchecked`. I've simply added `#[cfg(debug_assertions)]` to the checks for `ptr::read`/`ptr::write` because I was unable to come up with any (good) ideas for decreasing their impact. But for `NonNull::new_unchecked` I found that the majority of callers can use a different function, often a safe one.
Yes, this PR slows down the compile time of some programs. But in our benchmark suite it's never more than 1% icount, and the average icount change in debug-full programs is 0.22%. I think that is acceptable for such an improvement in developer experience.
https://github.com/rust-lang/rust/issues/120539#issuecomment-1922687101
internal: fix crash inside `filter_unnecessary_bounds` for a missing generic param
`@Wilfred` reported a crash here shortly after reporting https://github.com/rust-lang/rust-analyzer/issues/16516, which makes us think that the blast radius of ambiguities in Chalk can be larger than expected. This PR tries to be a bit more defensive as a result.
(The 20th frame is the salient frame in the backtrace below.)
<details>
<summary>Backtrace of the crash</summary>
```
request handler panicked: no entry found for key
backtrace:
0: stdx::panic_context::PanicContext::init::{{closure}}::{{closure}}::{{closure}}
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/stdx/src/panic_context.rs:32:43
1: stdx::panic_context::with_backtrace::{{closure}}
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/stdx/src/panic_context.rs:61:32
2: std:🧵:local::LocalKey<T>::try_with
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/thread/local.rs:270:16
3: std:🧵:local::LocalKey<T>::with
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/thread/local.rs:246:9
4: stdx::panic_context::with_backtrace
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/stdx/src/panic_context.rs:61:5
5: stdx::panic_context::PanicContext::init::{{closure}}::{{closure}}
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/stdx/src/panic_context.rs:31:21
6: stdx::panic_context::with_ctx::{{closure}}
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/stdx/src/panic_context.rs:53:20
7: std:🧵:local::LocalKey<T>::try_with
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/thread/local.rs:270:16
8: std:🧵:local::LocalKey<T>::with
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/thread/local.rs:246:9
9: <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/alloc/src/boxed.rs:2021:9
10: std::panicking::rust_panic_with_hook
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/panicking.rs:783:13
11: std::panicking::begin_panic_handler::{{closure}}
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/panicking.rs:657:13
12: std::sys_common::backtrace::__rust_end_short_backtrace
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/sys_common/backtrace.rs:170:18
13: rust_begin_unwind
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/panicking.rs:645:5
14: core::panicking::panic_fmt
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/core/src/panicking.rs:72:14
15: core::panicking::panic_display
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/core/src/panicking.rs:178:5
16: core::panicking::panic_str
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/core/src/panicking.rs:152:5
17: core::option::expect_failed
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/core/src/option.rs:1985:5
18: core::option::Option<T>::expect
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/core/src/option.rs:894:21
19: <std::collections:#️⃣:map::HashMap<K,V,S> as core::ops::index::Index<&Q>>::index
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/collections/hash/map.rs:1341:23
20: ide_assists::handlers::generate_function::filter_unnecessary_bounds::{{closure}}
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/ide-assists/src/handlers/generate_function.rs:911:71
21: core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &mut F>::call_once
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/core/src/ops/function.rs:305:13
22: core::option::Option<T>::map
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/core/src/option.rs:1072:29
23: <core::iter::adapters::map::Map<I,F> as core::iter::traits::iterator::Iterator>::next
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/core/src/iter/adapters/map.rs:103:26
24: ide_assists::handlers::generate_function::Graph::compute_reachable_nodes
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/ide-assists/src/handlers/generate_function.rs:1158:20
25: ide_assists::handlers::generate_function::filter_unnecessary_bounds
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/ide-assists/src/handlers/generate_function.rs:912:21
26: ide_assists::handlers::generate_function::fn_generic_params
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/ide-assists/src/handlers/generate_function.rs:640:5
27: ide_assists::handlers::generate_function::FunctionBuilder::from_call
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/ide-assists/src/handlers/generate_function.rs:283:13
28: ide_assists::handlers::generate_function::gen_fn
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/ide-assists/src/handlers/generate_function.rs:78:28
29: ide_assists::handlers::generate_function::generate_function
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/ide-assists/src/handlers/generate_function.rs:55:5
30: ide_assists::assists::{{closure}}
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/ide-assists/src/lib.rs:99:9
31: <core::slice::iter::Iter<T> as core::iter::traits::iterator::Iterator>::for_each
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/core/src/slice/iter/macros.rs:254:21
32: ide_assists::assists
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/ide-assists/src/lib.rs:98:5
33: ide::Analysis::assists_with_fixes::{{closure}}
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/ide/src/lib.rs:667:27
34: ide::Analysis::with_db::{{closure}}
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/ide/src/lib.rs:764:29
35: std::panicking::try::do_call
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/panicking.rs:552:40
36: std::panicking::try
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/panicking.rs:516:19
37: std::panic::catch_unwind
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/panic.rs:142:14
38: salsa::Cancelled::catch
at /var/twsvcscm/.cargo/registry/src/index.crates.io-6f17d22bba15001f/rust-analyzer-salsa-0.17.0-pre.5/src/lib.rs:631:15
39: ide::Analysis::with_db
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/ide/src/lib.rs:764:9
40: ide::Analysis::assists_with_fixes
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/ide/src/lib.rs:656:9
41: rust_analyzer::handlers::request::handle_code_action
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/rust-analyzer/src/handlers/request.rs:1149:19
42: rust_analyzer::dispatch::RequestDispatcher::on_with_thread_intent::{{closure}}::{{closure}}
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/rust-analyzer/src/dispatch.rs:198:54
43: std::panicking::try::do_call
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/panicking.rs:552:40
44: std::panicking::try
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/panicking.rs:516:19
45: std::panic::catch_unwind
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/panic.rs:142:14
46: rust_analyzer::dispatch::RequestDispatcher::on_with_thread_intent::{{closure}}
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/rust-analyzer/src/dispatch.rs:198:26
47: rust_analyzer::task_pool::TaskPool<T>::spawn::{{closure}}
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/rust-analyzer/src/task_pool.rs:26:33
48: stdx:🧵:pool::Pool::spawn::{{closure}}
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/stdx/src/thread/pool.rs:82:13
49: core::ops::function::FnOnce::call_once{{vtable.shim}}
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/core/src/ops/function.rs:250:5
50: <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/alloc/src/boxed.rs:2007:9
51: stdx:🧵:pool::Pool:🆕:{{closure}}
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/stdx/src/thread/pool.rs:61:29
52: stdx:🧵:Builder::spawn::{{closure}}
at /data/sandcastle/boxes/eden-trunk-hg-fbcode-fbsource/third-party/rust-analyzer/master/crates/stdx/src/thread.rs:66:13
53: std::sys_common::backtrace::__rust_begin_short_backtrace
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/sys_common/backtrace.rs:154:18
54: std:🧵:Builder::spawn_unchecked_::{{closure}}::{{closure}}
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/thread/mod.rs:529:17
55: <core::panic::unwind_safe::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/core/src/panic/unwind_safe.rs:272:9
56: std::panicking::try::do_call
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/panicking.rs:552:40
57: std::panicking::try
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/panicking.rs:516:19
58: std::panic::catch_unwind
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/panic.rs:142:14
59: std:🧵:Builder::spawn_unchecked_::{{closure}}
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/thread/mod.rs:528:30
60: core::ops::function::FnOnce::call_once{{vtable.shim}}
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/core/src/ops/function.rs:250:5
61: <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/alloc/src/boxed.rs:2007:9
62: <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/alloc/src/boxed.rs:2007:9
63: std::sys::unix:🧵:Thread:🆕:thread_start
at /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/std/src/sys/unix/thread.rs:108:17
64: start_thread
65: clone3
```
</details>
Always check the result of `pthread_mutex_lock`
Fixes#120147.
Instead of manually adding a list of "good" platforms, I've simply made the check unconditional. pthread's mutex is already quite slow on most platforms, so one single well-predictable branch shouldn't hurt performance too much.
When launching tests with --keep-stage option, startup objects
such as rsbegin.o an rsend.o may disappear from the corresponding
stageN compiler.
Fix issue #120784
The documentation for atomic integers says that they have the "same
in-memory representation" as their underlying integers. This might be
misconstrued as implying that they have the same layout. Therefore,
clarify that atomic integers' alignment is equal to their size.
When you stash an error, the error count is incremented. You can then
use the non-zero error count to get an `ErrorGuaranteed`. You can then
steal the error, which decrements the error count. You can then cancel
the error.
Example code:
```
fn unsound(dcx: &DiagCtxt) -> ErrorGuaranteed {
let sp = rustc_span::DUMMY_SP;
let k = rustc_errors::StashKey::Cycle;
dcx.struct_err("bogus").stash(sp, k); // increment error count on stash
let guar = dcx.has_errors().unwrap(); // ErrorGuaranteed from error count > 0
let err = dcx.steal_diagnostic(sp, k).unwrap(); // decrement error count on steal
err.cancel(); // cancel error
guar // ErrorGuaranteed with no error emitted!
}
```
This commit fixes the problem in the simplest way: by not counting
stashed errors in `DiagCtxt::{err_count,has_errors}`.
However, just doing this without any other changes leads to over 40 ui
test failures. Mostly because of uninteresting extra errors (many saying
"type annotations needed" when type inference fails), and in a few
cases, due to delayed bugs causing ICEs when no normal errors are
printed.
To fix these, this commit adds `DiagCtxt::stashed_err_count`, and uses
it in three places alongside `DiagCtxt::{has_errors,err_count}`. It's
dodgy to rely on it, because unlike `DiagCtxt::err_count` it can go up
and down. But it's needed to preserve existing behaviour, and at least
the three places that need it are now obvious.
internal: Migrate assists to the structured snippet API, part 6/7
Continuing from #16082
Migrates the following assists:
- `extract_function`
- `generate_getter_or_setter`
- `generate_impl`
- `generate_new`
- `replace_derive_with_manual_impl`
Would've been the final PR in the structured snippet migration series, but I didn't notice that `generate_trait_from_impl` started to use `{insert,replace}_snippet` when I first started the migration 😅. This appears to be a pretty self-contained change, so I'll leave that for a separate future PR.
This also removes the last usages of `render_snippet`, which was a follow up goal of #11638. 🎉
bors