Simplify `size/align_of_val<T: Sized>` to `size/align_of<T>` instead
This is relevant to things like `Box<[u8; 1024]>` where the drop looks at the `size_of_val` (since obviously it might be DST in general) but where we don't actually need to do that since it's always that same value for the `Sized` type.
(Equivalent to rust-lang/rust#152681, but flipped in the rebase so it can land before rust-lang/rust#152641 instead of depending on it.)
Perform many const checks in typeck
Some smaller diagnostic changes, the biggest ones avoided by https://github.com/rust-lang/rust/pull/148641
We should be able to move various checks in mir const checking to using `span_bug!` instead of reporting an error, just like mir typeck does as a sanity check. I would like to start doing so separately though, as this PR is a big enough (in what effects it causes, pun intended).
r? @fee1-dead
rustc_expand: improve diagnostics for non-repeatable metavars in repetition
Enhance `NoSyntaxVarsExprRepeat` by suggesting similarly named metavariables, distinguishing repeatable vs non-repeatable bindings, and listing available repeatable variables when no match exists.
Simplify the canonical enum clone branches to a copy statement
I have overhauled MatchBranchSimplification in this PR. This pass tries to unify statements one by one, which is more readable and extensible.
This PR also unifies the following pattern that is mostly generated by GVN into one basic block that contains the copy statement:
```rust
match a {
Foo::A(_) => *a,
Foo::B => Foo::B
}
```
Fixes https://github.com/rust-lang/rust/issues/128081.
Avoid delayed-bug ICE for malformed diagnostic attrs
Fixesrust-lang/rust#152744
Skip suggestions in `expected_lit` when parsing with `Recovery::Forbidden`, since this may later cancel `InvalidMetaItem`. This avoids creating delayed bugs that can be promoted to ICE.
Add a mir-opt test for alignment check generation [zero changes outside tests]
I wrote this as part of rust-lang/rust#152641 which it looks like I'm going to just close, so submitting the new test separately since we didn't have any mir-opt testing of this pass that I could find (at least `x test tests/mir-opt` didn't fail when I broke them) so figured it's something that should exist.
tests: rustc_public: Check const allocation for all variables (1 of 11 was missing)
In the test `tests/ui-fulldeps/rustc_public/check_allocation.rs` there is a check for constant allocations of local variables of this function:
fn other_consts() {{
let _max_u128 = u128::MAX;
let _min_i128 = i128::MIN;
let _max_i8 = i8::MAX;
let _char = 'x';
let _false = false;
let _true = true;
let _ptr = &BAR;
let _null_ptr: *const u8 = NULL;
let _tuple = TUPLE;
let _char_id = const {{ type_id::<char>() }};
let _bool_id = const {{ type_id::<bool>() }};
}}
The current test only finds 10 out of 11 allocations. The constant allocation for
let _ptr = &BAR;
is not checked, because the `SingleUseConsts` MIR pass does not optimize away that assignment. Add code to also collect constant allocation from assignment rvalues to find the constant allocation for that last variable.
Not only does this change make sense on its own, it also makes the test pass both with and without the `SingleUseConsts` pass.
Discovered while investigating ways to avoid [this tests/ui-fulldeps/rustc_public/check_allocation.rs](https://github.com/Enselic/rust/commit/d7fffabc31904434cd41304c2f419f8b4abc6e70#diff-c4a926f9e8ba22bcfb1e6f2491b79b80608ab018641f85f66d6718d7f3716a5e) hack from https://github.com/rust-lang/rust/pull/151426 which wants to stop running `SingleUseConsts` for non-optimized builds.
Fix ICE in transmutability error reporting when type aliases are normalized
Fixesrust-lang/rust#151462
Transmutability error reporting hit an ICE when type aliases were normalized for diagnostics. For example, when type
`JustUnit = ()` normalizes to `()`, the check passes unexpectedly even though the original check with `JustUnit` failed.
Fixed by adding a retry in the `Answer::Yes` arm that checks with the root obligation's types before panicking. The retry only occurs when the root obligation differs and is a Transmute trait predicate.
Also added a test that reproduces the original ICE.
Enhance `NoSyntaxVarsExprRepeat` by suggesting similarly named
metavariables, distinguishing repeatable vs non-repeatable bindings,
and listing available repeatable variables when no match exists.
Co-authored-by: Esteban Küber <esteban@kuber.com.ar>
Signed-off-by: Usman Akinyemi <usmanakinyemi202@gmail.com>
make `rustc_allow_const_fn_unstable` an actual `rustc_attrs` attribute
It is already named like one, but used to have its own feature gate, which this PR now removes in favor of just using `#![feature(rustc_attrs)]`.
Most of the diff is just the line number changes in `malformed-attrs.stderr`.
Fix invalid `mut T` suggestion for `&mut T` in missing lifetime error
close: rust-lang/rust#150077
When suggesting to return an owned value instead of a borrowed one, the diagnostic was only removing `&` instead of `&mut `, resulting in invalid syntax like `mut T`. This PR fixes the span calculation to properly cover the entire `&mut ` prefix.
remove the explicit error for old `rental` versions
This was converted to a hard error 20 months ago (in rust-lang/rust#125596). This seems like enough time for anyone still using it to notice, so remove the note entirely now.
In comparison, the explicit note for the more impactful `time` breakage was already removed after 6 months (rust-lang/rust#129343).
Closesrust-lang/rust#73933.
Closesrust-lang/rust#83125.
r? @petrochenkov
Unify wording of resolve error
Remove "failed to resolve" from the main error message and use the same format we use in other resolution errors "cannot find `name`":
```
error[E0433]: cannot find `nonexistent` in `existent`
--> $DIR/custom_attr_multisegment_error.rs:5:13
|
LL | #[existent::nonexistent]
| ^^^^^^^^^^^ could not find `nonexistent` in `existent`
```
The intent behind this is to end up with all resolve errors eventually be on the form of
```
error[ECODE]: cannot find `{NAME}` in {SCOPE}
--> $DIR/file.rs:5:13
|
LL | #[existent::nonexistent]
| ^^^^^^^^^^^ {SPECIFIC LABEL}
```
A category of errors that is interest are those that involve keywords. For example:
```
error[E0433]: cannot find `Self` in this scope
--> $DIR/issue-97194.rs:2:35
|
LL | fn bget(&self, index: [usize; Self::DIM]) -> bool {
| ^^^^ `Self` is only available in impls, traits, and type definitions
```
and
```
error[E0433]: cannot find `super` in this scope
--> $DIR/keyword-super.rs:2:9
|
LL | let super: isize;
| ^^^^^ there are too many leading `super` keywords
```
For these the label provides the actual help, while the message is less informative beyond telling you "couldn't find `name`".
This is an off-shoot of https://github.com/rust-lang/rust/pull/126810 and https://github.com/rust-lang/rust/pull/128086, a subset of the intended changes there with review comments applied.
r? @petrochenkov
Remove "failed to resolve" and use the same format we use in other resolution errors "cannot find `name`".
```
error[E0433]: cannot find `nonexistent` in `existent`
--> $DIR/custom_attr_multisegment_error.rs:5:13
|
LL | #[existent::nonexistent]
| ^^^^^^^^^^^ could not find `nonexistent` in `existent`
```
remove `#![allow(stable_features)]` from most tests
The only remaining usages are tests that specifically deal with feature gates.
This also deletes the very weird `#![feature(issue_5723_bootstrap)]`, a 13 year old "temporary fix" (rust-lang/rust#5723).
Revert "Fix an ICE in the vtable iteration for a trait reference"
The ICE fix appears to be unsound, causing a miscompilation involving `dyn Trait` and `async {}` which induces segfaults in safe Rust code. As the patch only hid an ICE, it does not seem worth the risk.
This addresses the problem in rust-lang/rust#152735 but it may still merit team discussion even if this PR is merged.
This reverts commit 8afd63610b, reversing changes made to 19122c03c7.
bors