[NLL] Improve closure region bound errors
Previously, we would report free region errors that originate from closure with the span of the closure and a "closure body requires ..." message. This is now updated to use a reason and span from inside the closure.
Thanks to reviewers Tyler Mandry (for pointing out that this is
ridiculous and we need a helper function), Niko Matsakis (for pointing
out that the span-calculation code only has a couple free variables),
and Esteban Küber (for pointing out `get_generics`).
Add the library search box on the 404 page
It actually has a link to search already, but it would be better to
have the search "box" as like index.md to be consistent.
<style> can be shared with index.md, but these pages currently
use https://doc.rust-lang.org/rust.css directly.
Fixes#14572.
Fix dead code lint for functions using impl Trait
Fixes https://github.com/rust-lang/rust/issues/54754
This is a minimal fix that doesn't add any new queries or touches unnecessary code. Please nominate for beta backport if wanted.
rustc: Allow `#[no_mangle]` anywhere in a crate
This commit updates the compiler to allow the `#[no_mangle]` (and
`#[export_name]` attributes) to be located anywhere within a crate.
These attributes are unconditionally processed, causing the compiler to
always generate an exported symbol with the appropriate name.
After some discussion on #54135 it was found that not a great reason
this hasn't been allowed already, and it seems to match the behavior
that many expect! Previously the compiler would only export a
`#[no_mangle]` symbol if it were *publicly reachable*, meaning that it
itself is `pub` and it's otherwise publicly reachable from the root of
the crate. This new definition is that `#[no_mangle]` *is always
reachable*, no matter where it is in a crate or whether it has `pub` or
not.
This should make it much easier to declare an exported symbol with a
known and unique name, even when it's an internal implementation detail
of the crate itself. Note that these symbols will persist beyond LTO as
well, always making their way to the linker.
Along the way this commit removes the `private_no_mangle_functions` lint
(also for statics) as there's no longer any need to lint these
situations. Furthermore a good number of tests were updated now that
symbol visibility has been changed.
Closes#54135
NLL: temps in block tail expression diagnostic
This change adds a diagnostic that explains when temporaries in a block tail expression live longer than block local variables that they borrow, and attempts to suggest turning the tail expresion into a statement (either by adding a semicolon at the end, when its result value is clearly unused, or by introducing a `let`-binding for the result value and then returning that).
Fix#54556
This commit updates the compiler to allow the `#[no_mangle]` (and
`#[export_name]` attributes) to be located anywhere within a crate.
These attributes are unconditionally processed, causing the compiler to
always generate an exported symbol with the appropriate name.
After some discussion on #54135 it was found that not a great reason
this hasn't been allowed already, and it seems to match the behavior
that many expect! Previously the compiler would only export a
`#[no_mangle]` symbol if it were *publicly reachable*, meaning that it
itself is `pub` and it's otherwise publicly reachable from the root of
the crate. This new definition is that `#[no_mangle]` *is always
reachable*, no matter where it is in a crate or whether it has `pub` or
not.
This should make it much easier to declare an exported symbol with a
known and unique name, even when it's an internal implementation detail
of the crate itself. Note that these symbols will persist beyond LTO as
well, always making their way to the linker.
Along the way this commit removes the `private_no_mangle_functions` lint
(also for statics) as there's no longer any need to lint these
situations. Furthermore a good number of tests were updated now that
symbol visibility has been changed.
Closes#54135
wasm: Explicitly export all symbols with LLD
This commit fixes an oddity on the wasm target where LTO can produce
working executables but plain old optimizations doesn't. The compiler
already knows what set of symbols it would like to export, but LLD only
discovers this list transitively through symbol visibilities. LLD may
not, however, always find all the symbols that we'd like to export.
For example if you depend on an rlib with a `#[no_mangle]` symbol, then
if you don't actually use anything from the rlib then the symbol won't
appear in the final artifact! It will appear, however, with LTO. This
commit attempts to rectify this situation by ensuring that all symbols
rustc would otherwise preserve through LTO are also preserved through
the linking process with LLD by default.
Rollup of 11 pull requests
Successful merges:
- #54078 (Expand the documentation for the `std::sync` module)
- #54717 (Cleanup rustc/ty part 1)
- #54781 (Add examples to `TyKind::FnDef` and `TyKind::FnPtr` docs)
- #54787 (Only warn about unused `mut` in user-written code)
- #54804 (add suggestion for inverted function parameters)
- #54812 (Regression test for #32382.)
- #54833 (make `Parser::parse_foreign_item()` return a foreign item or error)
- #54834 (rustdoc: overflow:auto doesn't work nicely on small screens)
- #54838 (Fix typo in src/libsyntax/parse/parser.rs)
- #54851 (Fix a regression in 1.30 by reverting #53564)
- #54853 (Remove unneccessary error from test, revealing NLL error.)
Failed merges:
r? @ghost
Remove unneccessary error from test, revealing NLL error.
Part of #52663.
Removes unnecessary type mismatch error from test that was hiding
borrow check error from NLL stderr.
r? @nikomatsakis
rustdoc: overflow:auto doesn't work nicely on small screens
This property was introduced by 3f92ff34b5, but looks it doesn't
overwrap even without the property.
Fixes#54672.
make `Parser::parse_foreign_item()` return a foreign item or error
Fixes `Parser::parse_foreign_item()` to follow the convention of `parse_trait_item()` and `parse_impl_item()` in that it *must* parse an item or return an error, and then the caller is responsible for detecting the closing delimiter.
This prevents it from looping endlessly on an unexpected token in `ext/expand.rs` where it was also leaking memory by continually pushing to `Parser::expected_tokens` via `Parser::check_keyword()`.
closes#54441
r? @petrochenkov
cc @dtolnay
Add examples to `TyKind::FnDef` and `TyKind::FnPtr` docs
This adds two examples to the docs of `TyKind::FnDef` and `TyKind::FnPtr`.
I found these two types a bit confusing when I learned about them and I think adding these examples might help others.
Cleanup rustc/ty part 1
Part 2 will follow soon; I wouldn't want these changes to rot too quickly.
- improve stack shifting and remove related allocations
- move a faster early return up
- improve allocations
- use Cow<str> where applicable
- simplify common patterns
- whitespace fixes
Expand the documentation for the `std::sync` module
I've tried to expand the documentation for Rust's synchronization primitives. The module level documentation explains why synchronization is required when working with a multiprocessor system,
and then links to the appropiate structure in this module.
Fixes#29377, since this should be the last item on the checklist (documentation for `Atomic*` was fixed in #44854, but not ticked off the checklist).
