Fixes#55001, #54744
Previously, SelectionContext would unconditionally cache the selection
result for an obligation. This worked fine for most users of
SelectionContext, but it caused an issue when used by Rustdoc's blanket
impl finder.
The issue occured when SelectionContext chose a ParamCandidate which
contained inference variables. Since inference variables can change
between calls to select(), it's not safe to cache the selection result -
the chosen candidate might not be applicable for future results, leading
to an ICE when we try to run confirmation.
This commit prevents SelectionContext from caching any ParamCandidate
that contains inference variables. This should always be completely
safe, as trait selection should never depend on a particular result
being cached.
I've also added some extra debug!() statements, which I found helpful in
tracking down this bug.
`compute_missing_ctors` is called a lot. It produces a vector, which can
be reasonably large (e.g. 100+ elements), but the vector is almost
always only checked for emptiness.
This commit changes `compute_missing_ctors` so it can be called in a
cheap way that just indicates if the vector would be empty. If
necessary, the function can subsequently be called in an expensive way
to compute the full vector.
This change reduces instruction counts for several benchmarks up to 2%.
Use a keyword in raw identifier example
That's a very small documentation fix. The text says "you can now use keywords as identifiers" but example didn't use a keyword and would work without raw identifiers.
Felix S. Klock II pointed out that this suggestion (introduced in
pull-request #43178 / eac74104) was being issued for one-field-struct
expected types (in which case it is misleading and outright wrong),
even though it was only intended for one-field enum-variants (most
notably, `Some`). Particularly tender-hearted code-historians may be
inclined to show mercy towards the author of #43178 on the grounds
that it's somewhat confusing that struct field definitions are given
in a type called `ty::VariantDef`.
Add a conditional to adhere to the original intent. (It would be
possible to generalize to structs, but not obviously net desirable.)
This adds a level of indentation, so the diff here is going to be
easier to read in ignore-whitespace mode (`-w`).
Resolves#55250.
The example was not as clear as it could be because it was making an assumption about the structure of the data in order to multiply the number of collection elements by the item size. This change demonstrates the idea more straightforwardly, without the calculation.
Changes:
````
new_ret_no_self: add sample from #3313 to Known Problems section.
Support multiline comments and hopefully fix panic
Check for comments in collapsible ifs
Resolve ICE in needless range loop lint
RIIR update_lints: Update changelog links
Rename if_let_redundant_pattern_matching to redundant_pattern_matching
Add lint for redundant pattern matching for explicit return boolean
Fix issue #3322: reword help message for len_zero
Simplify manual_memcpy suggestion in some cases
Fix dogfood
Update known problems for unnecessary_fold
RIIR update_lints: Replace lint count in README.md
Rename `active_lints` to `usable_lints`
Add comment on WalkDir vs. fs::read_dir
sort_by -> sort_by_key
Some more documentation for clippy_dev
Use `WalkDir` to also gather from subdirectories
Avoid linting `boxed_local` on trait implementations.
Website: Make lint categories linkable
Restore clippy_dummy's placeholder name
Swap order of methods in `needless_range_loop` suggestion in some cases
Revert "Exclude pattern guards from unnecessary_fold lint"
Exclude pattern guards from unnecessary_fold lint
````
[NLL] Use new region infer errors when explaining borrows
Use the new free region infer errors for explaining borrows
This gives at least some explanation for why a borrow is expected to
last for a certain free region. Also:
* Reports E0373: "closure may outlive the current function" with NLL.
* Special cases the case of returning a reference to (or value referencing) a local variable or temporary (E0515).
* Special case assigning a reference to a local variable in a closure to a captured variable. (E0521)
Closes#51026 - `regions-nested-fns-2.rs` isn't changed to that diagnostic, since that would not be the correct error here.
Closes#51169
cc #53882 - The error is (IMO) better now, but it could be better when we trace lifetimes in these error messages.
r? @nikomatsakis cc @pnkfelix
This gives at least some explanation for why a borrow is expected to
last for a certain free region. Also:
* Reports E0373: "closure may outlive the current function" with NLL.
* Special cases the case of returning a reference to (or value
referencing) a local variable or temporary (E0515).
* Special case assigning a reference to a local variable in a closure
to a captured variable.
Update Cargo, build curl/OpenSSL statically via features
In addition to to updating Cargo's submodule and Cargo's dependencies,
this also updates Cargo's build to build OpenSSL statically into Cargo
as well as libcurl unconditionally. This removes OpenSSL build logic
from the bootstrap code, and otherwise requests that even on OSX we
build curl statically.
