CTFE: tweak abort-on-uninhabited message
Having an "aborted execution:" makes it more consistent with the `Abort` terminator saying "the program aborted execution". Right now, at least one of the two errors will look weird in Miri.
r? `@oli-obk`
Clarify the 'default is only allowed on...' error
Code like
impl Foo {
default fn foo() {}
}
will trigger the error
error: `default` is only allowed on items in `impl` definitions
--> src/lib.rs:5:5
|
5 | default fn foo() {}
| -------^^^^^^^^^
| |
| `default` because of this
but that's very confusing! I *did* put it on an item in an impl!
So this commit changes the message to
error: `default` is only allowed on items in trait impls
--> src/lib.rs:5:5
|
5 | default fn foo() {}
| -------^^^^^^^^^
| |
| `default` because of this
Constier maybe uninit
I was playing around trying to make `[T; N]::zip()` in #79451 be `const fn`. One of the things I bumped into was `MaybeUninit::assume_init`. Is there any reason for the intrinsic `assert_inhabited<T>()` and therefore `MaybeUninit::assume_init` not being `const`?
---
I have as best as I could tried to follow the instruction in [library/core/src/intrinsics.rs](https://github.com/rust-lang/rust/blob/master/library/core/src/intrinsics.rs#L11). I have no idea what I am doing but it seems to compile after some slight changes after the copy paste. Is this anywhere near how this should be done?
Also any ideas for name of the feature gate? I guess `const_maybe_assume_init` is quite misleading since I have added some more methods. Should I add test? If so what should be tested?
remove this weird special case from promotion
Promotion has a special case to ignore interior mutability under some specific circumstances. The purpose of this PR is to figure out what changes if we remove that. Since `Cell::new` and friends only get promoted inside `const`/`static` initializers these days, it actually is not easy to exploit this case: you need something like
```rust
const TEST_INTERIOR_MUT: () = {
// The "0." case is already ruled out by not permitting any interior mutability in `const`.
let _val: &'static _ = &(Cell::new(1), 2).1;
};
```
I assume something like `&Some(&(Cell::new(1), 2).1)` would hit the nested case inside `validate_rvalue`... though I am not sure why that would not just trigger nested promotion, first promoting the inner reference and then the outer one?
Fixes https://github.com/rust-lang/rust/issues/67534 (by simply rejecting that code^^)
r? `@oli-obk` (but for now this is not meant to be merged!)
Cc `@rust-lang/wg-const-eval`
Code like
impl Foo {
default fn foo() {}
}
will trigger the error
error: `default` is only allowed on items in `impl` definitions
--> src/lib.rs:5:5
|
5 | default fn foo() {}
| -------^^^^^^^^^
| |
| `default` because of this
but that's very confusing! I *did* put it on an item in an impl!
So this commit changes the message to
error: `default` is only allowed on items in trait impls
--> src/lib.rs:5:5
|
5 | default fn foo() {}
| -------^^^^^^^^^
| |
| `default` because of this
Validate naked functions definitions
Validate that naked functions are defined in terms of a single inline assembly
block that uses only `const` and `sym` operands and has `noreturn` option.
Implemented as future incompatibility lint with intention to migrate it into
hard error. When it becomes a hard error it will ensure that naked functions are
either unsafe or contain an unsafe block around the inline assembly. It will
guarantee that naked functions do not reference functions parameters (obsoleting
part of existing checks from #79411). It will limit the definitions of naked
functions to what can be reliably supported. It will also reject naked functions
implemented using legacy LLVM style assembly since it cannot satisfy those
conditions.
https://github.com/rust-lang/rfcs/pull/2774https://github.com/rust-lang/rfcs/pull/2972
Const parameters can not be inferred with `_` help note
This should close: #79557
# Example output
```
error[E0747]: type provided when a constant was expected
--> inferred_const_note.rs:6:19
|
6 | let a = foo::<_, 2>([0, 1, 2]);
| ^
|
= help: Const parameters can not be inferred with `_`
error: aborting due to previous error
For more information about this error, try `rustc --explain E0747`.
```
r? `@lcnr`
A slightly clearer diagnostic when misusing const
Fixes#79598
This produces the following diagnostic:
"expected one of `>`, a const expression, lifetime, or type, found keyword `const`"
Instead of the previous, more confusing:
"expected one of `>`, const, lifetime, or type, found keyword `const`"
This might not be completely clear as some users might not understand what a const expression is, but I do believe this is an improvement.
Fix src/test/ui/env-vars.rs on 128-core machines on Windows
On Windows, the environment variable NUMBER_OF_PROCESSORS has special
meaning. Unfortunately, you can get different answers, depending on
whether you are enumerating all environment variables or querying a
specific variable. This was causing the src/test/ui/env-vars.rs test
to fail on machines with more than 64 processors when run on Windows.
check the recursion limit when finding a struct's tail
fixes#79437
This does a `delay_span_bug` (via `ty_error_with_message`) rather than emit a new error message, under the assumption that there will be an error elsewhere (even if the type isn't infinitely recursive, just deeper than the recursion limit, this appears to be the case).
On Windows, the environment variable NUMBER_OF_PROCESSORS has special
meaning. Unfortunately, you can get different answers, depending on
whether you are enumerating all environment variables or querying a
specific variable. This was causing the src/test/ui/env-vars.rs test
to fail on machines with more than 64 processors when run on Windows.
Revert "Auto merge of #79209
r? `@nikomatsakis`
This has caused some issues (#79560) so better to revert and try to come up with a proper fix without rush.
