Make `Decodable` and `Decoder` infallible.
`Decoder` has two impls:
- opaque: this impl is already partly infallible, i.e. in some places it
currently panics on failure (e.g. if the input is too short, or on a
bad `Result` discriminant), and in some places it returns an error
(e.g. on a bad `Option` discriminant). The number of places where
either happens is surprisingly small, just because the binary
representation has very little redundancy and a lot of input reading
can occur even on malformed data.
- json: this impl is fully fallible, but it's only used (a) for the
`.rlink` file production, and there's a `FIXME` comment suggesting it
should change to a binary format, and (b) in a few tests in
non-fundamental ways. Indeed #85993 is open to remove it entirely.
And the top-level places in the compiler that call into decoding just
abort on error anyway. So the fallibility is providing little value, and
getting rid of it leads to some non-trivial performance improvements.
Much of this PR is pretty boring and mechanical. Some notes about
a few interesting parts:
- The commit removes `Decoder::{Error,error}`.
- `InternIteratorElement::intern_with`: the impl for `T` now has the same
optimization for small counts that the impl for `Result<T, E>` has,
because it's now much hotter.
- Decodable impls for SmallVec, LinkedList, VecDeque now all use
`collect`, which is nice; the one for `Vec` uses unsafe code, because
that gave better perf on some benchmarks.
r? `@bjorn3`
build: dist: defer PlainSourceTarball
Apparently it changes some tool sources and invalidates their fingerprints, forcing us to build them several times (before and after vendoring sources).
I have not dug into why vendoring actually invalidates the figreprints, but moving the vendoring lower in the pipeline seems to avoid the issue.
I could imagine that we somehow write a .cargo/config somewhere which somehow makes subsequent builds use the vendored deps but I was not able to find anything.
I checked the sizes of generated archives pre and post patch and their are the same, so I hope there is no functional change.
Fixes#93033
Disable drop range tracking in generators
Generator drop tracking caused an ICE for generators involving the Never type (Issue #93161). Since this breaks a test case with miri, we temporarily disable drop tracking so miri is unblocked while we properly fix the issue.
update uclibc instructions for new toolchain, add link from platforms doc
2 quick things:
1) `libc` was updated to make use of features in a uclibc version more recent than the recommended toolchain in the target document, so I updated the link.
2) As has been done with other platforms, link directly from the platform support doc to the target-specific document.
Fix spacing for `·` between stability and source
This puts in an actual space (by adjusting the space-eating operators in our templates), updates the test, and remove the now-unnecessary CSS rule.
r? ``@GuillaumeGomez``
impl Not for !
The lack of this impl caused trouble for me in some degenerate cases of macro-generated code of the form `if !$cond {...}`, even without `feature(never_type)` on a stable compiler. Namely if `$cond` contains a `return` or `break` or similar diverging expression, which would otherwise be perfectly legal in boolean position, the code previously failed to compile with:
```console
error[E0600]: cannot apply unary operator `!` to type `!`
--> library/core/tests/ops.rs:239:8
|
239 | if !return () {}
| ^^^^^^^^^^ cannot apply unary operator `!`
```
rustdoc: remove dashed underline under main heading
This was removed in #92797 but accidentally re-introduced by a bad merge in #92861.
r? ```@camelid```
Reject unsupported naked functions
Transition unsupported naked functions future incompatibility lint into an error:
* Naked functions must contain a single inline assembly block. Introduced as future incompatibility lint in 1.50 #79653. Change into an error fixes a soundness issue described in #32489.
* Naked functions must not use any forms of inline attribute. Introduced as future incompatibility lint in 1.56 #87652.
Closes#32490.
Closes#32489.
r? ```@Amanieu``` ```@npmccallum``` ```@joshtriplett```
Print a helpful message if unwinding aborts when it reaches a nounwind function
This is implemented by routing `TerminatorKind::Abort` back through the panic handler, but with a special flag in the `PanicInfo` which indicates that the panic handler should *not* attempt to unwind the stack and should instead abort immediately.
This is useful for the planned change in https://github.com/rust-lang/lang-team/issues/97 which would make `Drop` impls `nounwind` by default.
### Code
```rust
#![feature(c_unwind)]
fn panic() {
panic!()
}
extern "C" fn nounwind() {
panic();
}
fn main() {
nounwind();
}
```
### Before
```
$ ./test
thread 'main' panicked at 'explicit panic', test.rs:4:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Illegal instruction (core dumped)
```
### After
```
$ ./test
thread 'main' panicked at 'explicit panic', test.rs:4:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
thread 'main' panicked at 'panic in a function that cannot unwind', test.rs:7:1
stack backtrace:
0: 0x556f8f86ec9b - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hdccefe11a6ac4396
1: 0x556f8f88ac6c - core::fmt::write::he152b28c41466ebb
2: 0x556f8f85d6e2 - std::io::Write::write_fmt::h0c261480ab86f3d3
3: 0x556f8f8654fa - std::panicking::default_hook::{{closure}}::h5d7346f3ff7f6c1b
4: 0x556f8f86512b - std::panicking::default_hook::hd85803a1376cac7f
5: 0x556f8f865a91 - std::panicking::rust_panic_with_hook::h4dc1c5a3036257ac
6: 0x556f8f86f079 - std::panicking::begin_panic_handler::{{closure}}::hdda1d83c7a9d34d2
7: 0x556f8f86edc4 - std::sys_common::backtrace::__rust_end_short_backtrace::h5b70ed0cce71e95f
8: 0x556f8f865592 - rust_begin_unwind
9: 0x556f8f85a764 - core::panicking::panic_no_unwind::h2606ab3d78c87899
10: 0x556f8f85b910 - test::nounwind::hade6c7ee65050347
11: 0x556f8f85b936 - test::main::hdc6e02cb36343525
12: 0x556f8f85b7e3 - core::ops::function::FnOnce::call_once::h4d02663acfc7597f
13: 0x556f8f85b739 - std::sys_common::backtrace::__rust_begin_short_backtrace::h071d40135adb0101
14: 0x556f8f85c149 - std::rt::lang_start::{{closure}}::h70dbfbf38b685e93
15: 0x556f8f85c791 - std::rt::lang_start_internal::h798f1c0268d525aa
16: 0x556f8f85c131 - std::rt::lang_start::h476a7ee0a0bb663f
17: 0x556f8f85b963 - main
18: 0x7f64c0822b25 - __libc_start_main
19: 0x556f8f85ae8e - _start
20: 0x0 - <unknown>
thread panicked while panicking. aborting.
Aborted (core dumped)
```
`Decoder` has two impls:
- opaque: this impl is already partly infallible, i.e. in some places it
currently panics on failure (e.g. if the input is too short, or on a
bad `Result` discriminant), and in some places it returns an error
(e.g. on a bad `Option` discriminant). The number of places where
either happens is surprisingly small, just because the binary
representation has very little redundancy and a lot of input reading
can occur even on malformed data.
- json: this impl is fully fallible, but it's only used (a) for the
`.rlink` file production, and there's a `FIXME` comment suggesting it
should change to a binary format, and (b) in a few tests in
non-fundamental ways. Indeed #85993 is open to remove it entirely.
And the top-level places in the compiler that call into decoding just
abort on error anyway. So the fallibility is providing little value, and
getting rid of it leads to some non-trivial performance improvements.
Much of this commit is pretty boring and mechanical. Some notes about
a few interesting parts:
- The commit removes `Decoder::{Error,error}`.
- `InternIteratorElement::intern_with`: the impl for `T` now has the same
optimization for small counts that the impl for `Result<T, E>` has,
because it's now much hotter.
- Decodable impls for SmallVec, LinkedList, VecDeque now all use
`collect`, which is nice; the one for `Vec` uses unsafe code, because
that gave better perf on some benchmarks.
Improve string concatenation suggestion
Before:
error[E0369]: cannot add `&str` to `&str`
--> file.rs:2:22
|
2 | let _x = "hello" + " world";
| ------- ^ -------- &str
| | |
| | `+` cannot be used to concatenate two `&str` strings
| &str
|
help: `to_owned()` can be used to create an owned `String` from a string reference. String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
|
2 | let _x = "hello".to_owned() + " world";
| ~~~~~~~~~~~~~~~~~~
After:
error[E0369]: cannot add `&str` to `&str`
--> file.rs:2:22
|
2 | let _x = "hello" + " world";
| ------- ^ -------- &str
| | |
| | `+` cannot be used to concatenate two `&str` strings
| &str
|
= note: string concatenation requires an owned `String` on the left
help: create an owned `String` from a string reference
|
2 | let _x = "hello".to_owned() + " world";
| +++++++++++
Improve error message for key="value" cfg arguments.
Hi, I ran into difficulties using the `--cfg` flag syntax, first hit when googling for the error was issue https://github.com/rust-lang/rust/issues/66450. Reading that issue, it sounded like the best way to improve the experience was to improve the error message, this is low risk and doesn't introduce any additional argument parsing.
The issue mentions that it is entirely dependent on the shell, while this may be true, I think guiding the the user into the realization that the quotes may need to be escaped is helpful. The two suggested escapings both work in Bash and in the Windows command prompt.
fyi `@ehuss`
Ensure that early-bound function lifetimes are always 'local'
During borrowchecking, we treat any free (early-bound) regions on
the 'defining type' as `RegionClassification::External`. According
to the doc comments, we should only have 'external' regions when
checking a closure/generator.
However, a plain function can also have some if its regions
be considered 'early bound' - this occurs when the region is
constrained by an argument, appears in a `where` clause, or
in an opaque type. This was causing us to incorrectly mark these
regions as 'external', which caused some diagnostic code
to act as if we were referring to a 'parent' region from inside
a closure.
This PR marks all instantiated region variables as 'local'
when we're borrow-checking something other than a
closure/generator/inline-const.
Add more granular `--exclude` in `x.py`
x.py has support for excluding some steps from the current invocation, but unfortunately that's not granular enough: some steps have the same name in different modules, and that prevents excluding only *some* of them.
As a practical example, let's say you need to run everything in `./x.py test` except for the standard library tests, as those tests require IPv6 and need to be executed on a separate machine. Before this commit, if you were to just run this:
./x.py test --exclude library/std
...the invocation would eventually fail, as that would not only exclude running the tests for the standard library (`library/std` in the `test` module), it would also exclude generating its documentation (`library/std` in the `doc` module), breaking linkchecker.
This commit adds support to the `--exclude` flag for prefixing paths with the name of the module their step is defined in, allowing the user to choose which module to exclude from:
./x.py test --exclude test::library/std
This maintains backward compatibility with existing invocations, while allowing more ganular exclusion. Examples of the behavior:
| `--exclude` | Docs | Tests |
| ------------------- | ------- | ------- |
| `library/std` | Skipped | Skipped |
| `doc::library/std` | Skipped | Run |
| `test::library/std` | Run | Skipped |
Note that this PR only changes the `--exclude` flag, and not in other `x.py` arguments or flags yet.
In the implementation I tried to limit the impact this would have with rustbuild as a whole as much as possible. The module name is extracted from the step by parsing the result of `std::any::type_name()`: unfortunately that output can change at any point in time, but IMO it's better than having to annotate all the existing and future `Step` implementations with the module name. I added a test to ensure the parsing works as expected, so hopefully if anyone makes changes to the output of `std::any::type_name()` they'll also notice they have to update rustbuild.
r? `@Mark-Simulacrum`
Override rustc version in ui and mir-opt tests to get stable hashes
Building a dozen separate regexps for each test in compiletest consumes significant amounts of CPU cycles.
UI test timings on my machine:
OLD: 39.63s
NEW: 30.27s
Generator drop tracking caused an ICE for generators involving the Never
type (Issue #93161). Since this breaks miri, we temporarily disable drop
tracking so miri is unblocked while we properly fix the issue.
x.py has support for excluding some steps from the invocation, but
unfortunately that's not granular enough: some steps have the same name
in different modules, and that prevents excluding only *some* of them.
As a practical example, let's say you need to run everything in `./x.py
test` except for the standard library tests, as those tests require IPv6
and need to be executed on a separate machine. Before this commit, if
you were to just run this:
./x.py test --exclude library/std
...the execution would fail, as that would not only exclude running the
tests for the standard library, it would also exclude generating its
documentation (breaking linkchecker).
This commit adds support for an optional module annotation in --exclude
paths, allowing the user to choose which module to exclude from:
./x.py test --exclude test::library/std
This maintains backward compatibility, but also allows for more ganular
exclusion. More examples on how this works:
| `--exclude` | Docs | Tests |
| ------------------- | ------- | ------- |
| `library/std` | Skipped | Skipped |
| `doc::library/std` | Skipped | Run |
| `test::library/std` | Run | Skipped |
Note that the new behavior only works in the `--exclude` flag, and not
in other x.py arguments or flags yet.
Rollup of 17 pull requests
Successful merges:
- #91032 (Introduce drop range tracking to generator interior analysis)
- #92856 (Exclude "test" from doc_auto_cfg)
- #92860 (Fix errors on blanket impls by ignoring the children of generated impls)
- #93038 (Fix star handling in block doc comments)
- #93061 (Only suggest adding `!` to expressions that can be macro invocation)
- #93067 (rustdoc mobile: fix scroll offset when jumping to internal id)
- #93086 (Add tests to ensure that `let_chains` works with `if_let_guard`)
- #93087 (Fix src/test/run-make/raw-dylib-alt-calling-convention)
- #93091 (⬆ chalk to 0.76.0)
- #93094 (src/test/rustdoc-json: Check for `struct_field`s in `variant_tuple_struct.rs`)
- #93098 (Show a more informative panic message when `DefPathHash` does not exist)
- #93099 (rustdoc: auto create output directory when "--output-format json")
- #93102 (Pretty printer algorithm revamp step 3)
- #93104 (Support --bless for pp-exact pretty printer tests)
- #93114 (update comment for `ensure_monomorphic_enough`)
- #93128 (Add script to prevent point releases with same number as existing ones)
- #93136 (Backport the 1.58.1 release notes to master)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Transition unsupported naked functions future incompatibility lint into
an error:
* Naked functions must contain a single inline assembly block.
Introduced as future incompatibility lint in 1.50 #79653.
Change into an error fixes a soundness issue described in #32489.
* Naked functions must not use any forms of inline attribute.
Introduced as future incompatibility lint in 1.56 #87652.
Building a dozen separate regexps for each test in compiletest consumes significant amounts of CPU cycles.
Using `RUSTC_FORCE_INCR_COMP_ARTIFACT_HEADER` stabilizes hashes calcuated for the individual tests so
no test-dependent normalization is needed. Hashes for the standard library still change so some
normalizations are still needed.
Add script to prevent point releases with same number as existing ones
This will hopefully prevent what happened today with #93110 and #93121, where we built point release artifacts without changing version numbers, thus requiring another PR to change the version number.
r? `@Mark-Simulacrum`
Support --bless for pp-exact pretty printer tests
I ran into this while working on the stack of PRs containing #93102. `x.py test src/test/pretty --bless` previously would `fatal` instead of blessing the input files.
Tested by making a silly pretty-printer tweak and running the above command: 98823c3929ebfe796786345c5ee713f63317d9c6
rustdoc: auto create output directory when "--output-format json"
This PR allows rustdoc to automatically create output directory in case it does not exist (when run with `--output-format json`).
This fixes rustdoc crash:
````
$ rustdoc --output-format json -Z unstable-options src/main.rs
error: couldn't generate documentation: No such file or directory (os error 2)
|
= note: failed to create or modify "doc/main.json"
error: aborting due to previous error
````
With this fix behavior of `rustdoc --output-format json` becomes consistent with `rustdoc --output-format html` (which already auto-creates output directory if it's missing)
src/test/rustdoc-json: Check for `struct_field`s in `variant_tuple_struct.rs`
The presence of `struct_field`s is being checked for already in
`variant_struct.rs`. We should also check for them in `variant_tuple_struct.rs`.
This PR is one small step towards resolving #92945.
Fix src/test/run-make/raw-dylib-alt-calling-convention
Fix the test headers so that the test now runs on all intended platforms; it is currently ignored on all platforms because the headers are incorrect. Also comment out a couple of function calls that fail because of an unrelated problem, described in issue #91167.
