this test was included for demonstrative and discussion purposes but does not test what its name alleges - in fact it does not test much of value at all!
as mentioned in this comment, https://github.com/rust-lang/rust/pull/122770#issuecomment-2474256965 , writing a correct test for this codegen outcome is difficult (partially because the public interface to std::fmt intentionally includes an #[inline(never)] function!), so to test this correctly will require more than i can offer in 122770.
PR 130999 added the file_lock feature, but libc does not define
flock() for the Solaris platform leading to a compilation error.
Additionally, I went through all the Tier 2 platforms and read through
their documentation to see whether flock was implemented. This turned up
5 more Unix platforms where flock is not supported, even though it may
exist in the libc crate.
[perf] rustdoc: Perform less work when cleaning middle::ty parenthesized generic args
CC #132697. I presume the perf regression it caused (if real) boils down to query invocation overhead, namely of `def_kind` & `trait_def` as we don't seem to be decoding more often from the crate metadata.
I won't try the obvious and reduce the amount of query calls by threading information via params as that would render the code awkward.
So instead I'm simply trying to attack some low-hanging fruits in the vicinity.
---
Previously, we would `clean_middle_generic_args` *unconditionally* inside `clean_middle_generic_args_with_constraints` even though we didn't actually use its result for parenthesized generic args (`Trait(...) -> ...`).
Now, we only call `clean_middle_generic_args` when necessary. Lastly, I've simplified `clean_middle_generic_args_with_constraints`.
---
r? ghost
pipe2 allows the newly-created pipe to atomically be CLOEXEC.
pipe2 was added to illumos a long time ago:
5dbfd19ad5.
I've verified that this change passes all tests.
Closes https://github.com/rust-lang/rust-clippy/issues/10118
This lint checks `map_or` method calls to check if they can be
consolidated down to something simpler and/or more readable.
For example, the code
```rs
let x = Some(5);
x.map_or(false, |n| n == 5)
```
can be rewritten as
```rs
let x = Some(5);
x == Some(5)
```
In addition, when the closure is more complex, the code can be altered
from, say,
```rs
let x = Ok::<Vec<i32>, i32>(vec![5]);
x.map_or(false, |n| n == [5])
```
into
```rs
let x = Ok::<Vec<i32>, i32>(vec![5]);
x.is_some_and(|n| n == [5])
```
This lint also considers cases where the `map_or` can be chained with
other method calls, and accommodates accordingly by adding extra
parentheses as needed to the suggestion.
changelog: add new lint `unnecessary_map_or`
CFI: Append debug location to CFI blocks
Currently we're not appending debug locations to the inserted CFI blocks. This shows up in #132615 and #100783. This change fixes that by passing down the debug location to the CFI type-test generation and appending it to the blocks.
Credits also belong to `@jakos-sec` who worked with me on this.
clarify `must_produce_diag` ICE for debugging
We have a sanity check to ensure the expensive `trimmed_def_paths` functions are called only when producing diagnostics, and not e.g. on the happy path. The panic often happens IME during development because of randomly printing stuff, causing an ICE if no diagnostics were also emitted.
I have this change locally but figured it could be useful to others, so this PR clarifies the message when this happens during development.
The output currently looks like this by default; it's a bit confusing with words missing:
```
thread 'rustc' panicked at compiler/rustc_errors/src/lib.rs:628:17:
must_produce_diag: `trimmed_def_paths` called but no diagnostics emitted; `with_no_trimmed_paths` for debugging. called at: disabled backtrace
stack backtrace:
0: 0x7ffff79570f6 - std::backtrace_rs::backtrace::libunwind::trace::h33576c57327a3cea
at .../library/std/src/../../backtrace/src/backtrace/libunwind.rs:116:5
1: 0x7ffff79570f6 - std::backtrace_rs::backtrace::trace_unsynchronized::h7972a09393b420db
at .../library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
2: 0x7ffff79570f6 - std::sys::backtrace::_print_fmt::hae8c5bbfbf7a8322
at .../library/std/src/sys/backtrace.rs:66:9
3: 0x7ffff79570f6 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::h1fd6a7a210f5b535
...
```
The new output mentions how to get more information and locate where the `with_no_trimmed_paths` call needs to be added.
1. By default, backtraces are disabled:
```
thread 'rustc' panicked at compiler/rustc_errors/src/lib.rs:642:17:
`trimmed_def_paths` called, diagnostics were expected but none were emitted. Use `with_no_trimmed_paths` for debugging. Backtraces are currently disabled: set `RUST_BACKTRACE=1` and re-run to see where it happened.
stack backtrace:
0: 0x7ffff79565f6 - std::backtrace_rs::backtrace::libunwind::trace::h33576c57327a3cea
...
```
2. With backtraces enabled:
```
thread 'rustc' panicked at compiler/rustc_errors/src/lib.rs:642:17:
`trimmed_def_paths` called, diagnostics were expected but none were emitted. Use `with_no_trimmed_paths` for debugging. This happened in the following `must_produce_diag` call's backtrace:
0: <rustc_errors::DiagCtxtHandle>::set_must_produce_diag
at .../compiler/rustc_errors/src/lib.rs:1133:58
1: <rustc_session::session::Session>::record_trimmed_def_paths
at .../compiler/rustc_session/src/session.rs:327:9
2: rustc_middle::ty::print::pretty::trimmed_def_paths
at .../compiler/rustc_middle/src/ty/print/pretty.rs:3351:5
...
```
A `\n` could be added here or there, but it didn't matter much whenever I hit this case with the new message.
