It's always good to make `rustc_middle` smaller. `rustc_interface` is
the best destination, because it's the only crate that calls
`get_recursive_limit`.
It's similar to the other limits, e.g. obtained via `get_limit`. So it
makes sense to handle it consistently with the other limits. We now use
`Limit`/`usize` in most places instead of `Option<usize>`, so we use
`Limit::new(usize::MAX)`/`usize::MAX` to emulate how `None` used to work.
The commit also adds `Limit::unlimited`.
The following is a weird pattern for a file within `rustc_middle`:
```
use rustc_middle::aaa;
use crate::bbb;
```
More sensible and standard would be this:
```
use crate::{aaa, bbb};
```
I.e. we generally prefer using `crate::` to using a crate's own name.
(Exceptions are things like in macros where `crate::` doesn't work
because the macro is used in multiple crates.)
This commit fixes a bunch of these weird qualifiers.
`NamedVarMap` is extremely similar to `ResolveBoundVars`. The former
contains two `UnordMap<ItemLocalId, T>` fields (obscured behind
`ItemLocalMap` typedefs). The latter contains two
`SortedMap<ItemLocalId, T>` fields. We construct a `NamedVarMap` and
then convert it into a `ResolveBoundVars` by sorting the `UnordMap`s,
which is unnecessary busywork.
This commit removes `NamedVarMap` and constructs a `ResolveBoundVars`
directly. `SortedMap` and `NamedVarMap` have slightly different
perf characteristics during construction (e.g. speed of insertion) but
this code isn't hot enough for that to matter.
A few details to note.
- A `FIXME` comment is removed.
- The detailed comments on the fields of `NamedVarMap` are copied to
`ResolveBoundVars` (which has a single, incorrect comment).
- `BoundVarContext::map` is renamed.
- `ResolveBoundVars` gets a derived `Default` impl.
deprecate `std::intrinsics::transmute` etc, use `std::mem::*` instead
The `rustc_allowed_through_unstable_modules` attribute lets users call `std::mem::transmute` as `std::intrinsics::transmute`. The former is a reexport of the latter, and for a long time we didn't properly check stability for reexports, so making this a hard error now would be a breaking change for little gain. But at the same time, `std::intrinsics::transmute` is not the intended path for this function, so I think it is a good idea to show a deprecation warning when that path is used. This PR implements that, for all the functions in `std::intrinsics` that carry the attribute.
I assume this will need ``@rust-lang/libs-api`` FCP.
Treat safe target_feature functions as unsafe by default [less invasive variant]
This unblocks
* #134090
As I stated in https://github.com/rust-lang/rust/pull/134090#issuecomment-2541332415 I think the previous impl was too easy to get wrong, as by default it treated safe target feature functions as safe and had to add additional checks for when they weren't. Now the logic is inverted. By default they are unsafe and you have to explicitly handle safe target feature functions.
This is the less (imo) invasive variant of #134317, as it doesn't require changing the Safety enum, so it only affects FnDefs and nothing else, as it should.
`rustc_span::symbol` defines some things that are re-exported from
`rustc_span`, such as `Symbol` and `sym`. But it doesn't re-export some
closely related things such as `Ident` and `kw`. So you can do `use
rustc_span::{Symbol, sym}` but you have to do `use
rustc_span::symbol::{Ident, kw}`, which is inconsistent for no good
reason.
This commit re-exports `Ident`, `kw`, and `MacroRulesNormalizedIdent`,
and changes many `rustc_span::symbol::` qualifiers in `compiler/` to
`rustc_span::`. This is a 200+ net line of code reduction, mostly
because many files with two `use rustc_span` items can be reduced to
one.
It is treated as a map already. This is using FxIndexMap rather than
UnordMap because the latter doesn't provide an api to pick a single
value iff all values are equal, which each_linked_rlib depends on.
take 2
open up coroutines
tweak the wordings
the lint works up until 2021
We were missing one case, for ADTs, which was
causing `Result` to yield incorrect results.
only include field spans with significant types
deduplicate and eliminate field spans
switch to emit spans to impl Drops
Co-authored-by: Niko Matsakis <nikomat@amazon.com>
collect drops instead of taking liveness diff
apply some suggestions and add explantory notes
small fix on the cache
let the query recurse through coroutine
new suggestion format with extracted variable name
fine-tune the drop span and messages
bugfix on runtime borrows
tweak message wording
filter out ecosystem types earlier
apply suggestions
clippy
check lint level at session level
further restrict applicability of the lint
translate bid into nop for stable mir
detect cycle in type structure
Use backticks instead of single quotes for library feature names in diagnostics
This PR changes the text of library feature errors for using unstable or body-unstable items. Displaying library feature names in backticks is consistent with other diagnostics (e.g. those from `rustc_passes`) and with the `reason`s on unstable attributes in the library. Additionally, this simplifies diagnostics when supporting multiple unstable attributes on items (see #131824) since `DiagSymbolList` also displays symbols using backticks.
This is consistent with all other diagnostics I could find containing
features and enables the use of `DiagSymbolList` for generalizing
diagnostics for unstable library features to multiple features.
Rescope temp lifetime in if-let into IfElse with migration lint
Tracking issue #124085
This PR shortens the temporary lifetime to cover only the pattern matching and consequent branch of a `if let`.
At the expression location, means that the lifetime is shortened from previously the deepest enclosing block or statement in Edition 2021. This warrants an Edition change.
Coming with the Edition change, this patch also implements an edition lint to warn about the change and a safe rewrite suggestion to preserve the 2021 semantics in most cases.
Related to #103108.
Related crater runs: https://github.com/rust-lang/rust/pull/129466.
Clean up a few minor refs in `format!` macro, as it has a performance cost. Apparently the compiler is unable to inline `format!("{}", &variable)`, and does a run-time double-reference instead (format macro already does one level referencing). Inlining format args prevents accidental `&` misuse.
DependencyList: removed outdated comment
Comment was outdated. Didn't updated description, as `Linkage` enum have descriptive names.
Also added fixme about moving this file to rustc_metadata.
