Implement RFC3695 Allow boolean literals as cfg predicates
This PR implements https://github.com/rust-lang/rfcs/pull/3695: allow boolean literals as cfg predicates, i.e. `cfg(true)` and `cfg(false)`.
r? `@nnethercote` *(or anyone with parser knowledge)*
cc `@clubby789`
Refactoring to `OpaqueTyOrigin`
Pulled out of a larger PR that uses these changes to do cross-crate encoding of opaque origin, so we can use them for edition 2024 migrations. These changes should be self-explanatory on their own, tho 😄
Add `File` constructors that return files wrapped with a buffer
In addition to the light convenience, these are intended to raise visibility that buffering is something you should consider when opening a file, since unbuffered I/O is a common performance footgun to Rust newcomers.
ACP: https://github.com/rust-lang/libs-team/issues/446
Tracking Issue: #130804
linker: Allow MSVC to use import libraries following the Meson/MinGW convention
Hi all,
This PR implements support for `MsvcLinker` to use import libraries following Meson and the MinGW toolchain's naming convention. Meson [follows the `libfoo.dll.a` naming convention](https://mesonbuild.com/FAQ.html#why-does-building-my-project-with-msvc-output-static-libraries-called-libfooa) to disambiguate between static and import libraries.
This support already existed for static libraries (see #100101), but not for dynamic libraries. The latter case was added by duplicating the logic in `native_libs::find_native_static_library`, but a separate case was added in `link_dylib_by_name` for the Windows CRT libraries which must be handled by the linker itself.
See for prerequisites #129366, #126094, and #128370.
All feedback is appreciated!
Fixes#122455
cc `@sdroege` `@nirbheek`
Correctly handle stability of `#[diagnostic]` attributes
This commit changes the way we treat the stability of attributes in the
`#[diagnostic]` namespace. Instead of relaying on ad-hoc checks to
ensure at call side that a certain attribute is really usable at that
location it centralises the logic to one place. For diagnostic
attributes comming from other crates it just skips serializing
attributes that are not stable and that do not have the corresponding
feature enabled. For attributes from the current crate we can just use
the feature information provided by `TyCtx`.
r? `@compiler-errors`
This commit changes the way we treat the stability of attributes in the
`#[diagnostic]` namespace. Instead of relaying on ad-hoc checks to
ensure at call side that a certain attribute is really usable at that
location it centralises the logic to one place. For diagnostic
attributes comming from other crates it just skips serializing
attributes that are not stable and that do not have the corresponding
feature enabled. For attributes from the current crate we can just use
the feature information provided by `TyCtx`.
Make decoding non-optional `LazyArray` panic if not set
Tables may be [defined](9649706ead/compiler/rustc_metadata/src/rmeta/mod.rs (L377)) as `optional:` or `defaulted:`. If optional, if we try to read a value from a key that was never encoded, we should panic. This has high value in ensuring correctness over a defaulted table, so the tradeoff is worth considering, since it signals the compiler has a buggy encode impl, rather than just defaulting to a value.
HOWEVER, `optional:` arrays were side-stepping this. So this PR fixes that, and makes `optional:` tables of `LazyArray` act like `LazyValue`, and panic if it's not assigned a value during encoding.
During this PR, I found that `deduced_param_attrs` has buggy (?? i think??) implementation where it will refuse to encode cross-crate `deduced_param_attrs` unless we're codegening, we're optimizing the library, and incremental is disabled. This seems incredibly wrong, but I don't want to fix it in this PR.
9649706ead/compiler/rustc_metadata/src/rmeta/encoder.rs (L1733-L1747)
Stop using `ty::GenericPredicates` for non-predicates_of queries
`GenericPredicates` is a struct of several parts: A list of of an item's own predicates, and a parent def id (and some effects related stuff, but ignore that since it's kinda irrelevant). When instantiating these generic predicates, it calls `predicates_of` on the parent and instantiates its predicates, and appends the item's own instantiated predicates too:
acb4e8b625/compiler/rustc_middle/src/ty/generics.rs (L407-L413)
Notice how this should result in a recursive set of calls to `predicates_of`... However, `GenericPredicates` is *also* misused by a bunch of *other* queries as a convenient way of passing around a list of predicates. For these queries, we don't ever set the parent def id of the `GenericPredicates`, but if we did, then this would be very easy to mistakenly call `predicates_of` instead of some other intended parent query.
Given that footgun, and the fact that we don't ever even *use* the parent def id in the `GenericPredicates` returned from queries like `explicit_super_predicates_of`, It really has no benefit over just returning `&'tcx [(Clause<'tcx>, Span)]`.
This PR additionally opts to wrap the results of `EarlyBinder`, as we've tended to use that in the return type of these kinds of queries to properly convey that the user has params to deal with, and it also gives a convenient way of iterating over a slice of things after instantiating.
Simplify some extern providers
Simplifies some extern crate providers:
1. Generalize the `ProcessQueryValue` identity impl to work on non-`Option` types.
2. Allow `ProcessQueryValue` to wrap its output in an `EarlyBinder`, to simplify `explicit_item_bounds`/`explicit_item_super_predicates`.
3. Use `{ table }` and friends more when possible.
linker: Synchronize native library search in rustc and linker
Also search for static libraries with alternative naming (`libname.a`) on MSVC when producing executables or dynamic libraries, and not just rlibs.
This unblocks https://github.com/rust-lang/rust/pull/123436.
try-job: x86_64-msvc
Move `'tcx` lifetime off of impl and onto methods for `CrateMetadataRef`
Unconstrained type and const variables are not allowed, but unconstrained lifetimes are. This is not very good style, though, and it leads to unnecessary captures of a lifetime in edition 2024 (not that it matters, but it does trigger the edition migration lint).
Replace ASCII control chars with Unicode Control Pictures
Replace ASCII control chars like `CR` with Unicode Control Pictures like `␍`:
```
error: bare CR not allowed in doc-comment
--> $DIR/lex-bare-cr-string-literal-doc-comment.rs:3:32
|
LL | /// doc comment with bare CR: '␍'
| ^
```
Centralize the checking of unicode char width for the purposes of CLI display in one place. Account for the new replacements. Remove unneeded tracking of "zero-width" unicode chars, as we calculate these in the `SourceMap` as needed now.
Remove unnecessary impl sorting in queries and metadata
Removes unnecessary impl sorting because queries already return their keys in HIR definition order: https://github.com/rust-lang/rust/issues/120371#issuecomment-1926422838
r? `@cjgillot` or `@lcnr` -- unless I totally misunderstood what was being asked for here? 😆fixes#120371
No longer track "zero-width" chars in `SourceMap`, read directly from the line when calculating the `display_col` of a `BytePos`. Move `char_width` to `rustc_span` and use it from the emitter.
This change allows the following to properly align in terminals (depending on the font, the replaced control codepoints are rendered as 1 or 2 width, on my terminal they are rendered as 1, on VSCode text they are rendered as 2):
```
error: this file contains an unclosed delimiter
--> $DIR/issue-68629.rs:5:17
|
LL | ␜␟ts␀![{i
| -- unclosed delimiter
| |
| unclosed delimiter
LL | ␀␀ fn rݻoa>rݻm
| ^
```
Implement new effects desugaring
cc `@rust-lang/project-const-traits.` Will write down notes once I have finished.
* [x] See if we want `T: Tr` to desugar into `T: Tr, T::Effects: Compat<true>`
* [x] Fix ICEs on `type Assoc: ~const Tr` and `type Assoc<T: ~const Tr>`
* [ ] add types and traits to minicore test
* [ ] update rustc-dev-guide
Fixes#119717Fixes#123664Fixes#124857Fixes#126148
Introduce `{IndexNewtype,SyntaxContext}::from_u16` for convenience because small indices are sometimes encoded as `u16`.
Use `SpanData::span` instead of `Span::new` where appropriate.
Add a clarifying comment about decoding span parents.
Implement `needs_async_drop` in rustc and optimize async drop glue
This PR expands on #121801 and implements `Ty::needs_async_drop` which works almost exactly the same as `Ty::needs_drop`, which is needed for #123948.
Also made compiler's async drop code to look more like compiler's regular drop code, which enabled me to write an optimization where types which do not use `AsyncDrop` can simply forward async drop glue to `drop_in_place`. This made size of the async block from the [async_drop test](67980dd6fb/tests/ui/async-await/async-drop.rs) to decrease by 12%.
Remove more `#[macro_use] extern crate tracing`
Because explicit importing of macros via use items is nicer (more standard and readable) than implicit importing via `#[macro_use]`. Continuing the work from #124511 and #124914.
r? `@jackh726`
Add a footer in FileEncoder and check for it in MemDecoder
We have a few reports of ICEs due to decoding failures, where the fault does not lie with the compiler. The goal of this PR is to add some very lightweight and on-by-default validation to the compiler's outputs. If validation fails, we emit a fatal error for rmeta files in general that mentions the path that didn't load, and for incremental compilation artifacts we emit a verbose warning that tries to explain the situation and treat the artifacts as outdated.
The validation currently implemented here is very crude, and yet I think we have 11 ICE reports currently open (you can find them by searching issues for `1002111927320821928687967599834759150`) which this simple validation would have detected. The structure of the code changes here should permit the addition of further validation code, such as a checksum, if it is merited. I would like to have code to detect corruption such as reported in https://github.com/rust-lang/rust/issues/124719, but I'm not yet sure how to do that efficiently, and this PR is already a good size.
The ICE reports I have in mind that this PR would have smoothed over are:
https://github.com/rust-lang/rust/issues/124469https://github.com/rust-lang/rust/issues/123352https://github.com/rust-lang/rust/issues/123376 [^1]
https://github.com/rust-lang/rust/issues/99763https://github.com/rust-lang/rust/issues/93900.
---
[^1]: This one might be a compiler bug, but even if it is I think the workflow described is pushing the envelope of what we can support. This issue is one of the reasons this warning still asks people to file an issue.
always print nice 'std not found' error when std is not found
Fixes https://github.com/rust-lang/miri/issues/3529
Arguably Miri is doing something odd by letting people create no-std sysroots for arbitrary targets -- but equally arguably, there's no good reason for rustc to special-case the host triple here. Being a non-host triple does not imply the target is a no-std target, after all.
Enable `CrateNum` query feeding via `TyCtxt`
Instead of having a magic function that violates some `TyCtxtFeed` invariants, add a `create_def` equivalent for `CrateNum`s.
Note that this still isn't tracked by the query system (unlike `create_def`), and that feeding most `CrateNum` queries for crates other than the local one will likely cause performance regressions.
These things should be attempted on their own separately, but this PR should stand on its own
weak lang items are not allowed to be #[track_caller]
For instance the panic handler will be called via this import
```rust
extern "Rust" {
#[lang = "panic_impl"]
fn panic_impl(pi: &PanicInfo<'_>) -> !;
}
```
A `#[track_caller]` would add an extra argument and thus make this the wrong signature.
The 2nd commit is a consistency rename; based on the docs [here](https://doc.rust-lang.org/unstable-book/language-features/lang-items.html) and [here](https://rustc-dev-guide.rust-lang.org/lang-items.html) I figured "lang item" is more widely used. (In the compiler output, "lang item" and "language item" seem to be pretty even.)
