Remove semicolon note
In reference to issue #46186
r? @estebank
First time doing a pull request, if there are any suggestions on how to improve this please let me know.
@jjolly
MIR: Fix value moved diagnose messages
#45960. I believe this will take a different approach. Simply replacing all nouns to verbs (`desired_action`) messes up the message `use of moved value` (although fixes the message in original issue). Here is what happens:
<pre>
$ rustc -Zborrowck-mir src/test/ui/borrowck/borrowck-reinit.rs
error[E0382]: <b>used</b> of moved value: `x` (Mir)
--> src/test/ui/borrowck/borrowck-reinit.rs:18:16
|
17 | drop(x);
| - value moved here
18 | let _ = (1,x);
| ^ value used here after move
error: aborting due to 2 previous errors
</pre>
(Notice: *"**used** of moved value: `x`"* instead of *"**use**"*)
Which does not seem to be okay.
After experimenting a bit, it looks like [`report_use_of_moved_value()`](1dc0b573e7/src/librustc_mir/borrow_check.rs (L1319)) tries to handle both these messages by taking in only one form of`desired_action`.
These messages rise from: *"[{noun} of moved value](1dc0b573e7/src/librustc_mir/borrow_check.rs (L1338-L1342))"* and *"[value {verb} here after move](1dc0b573e7/src/librustc_mir/borrow_check.rs (L1343))"*.
This PR fixes *"value {verb} here after move"* type messages by passing a corresponding verb (`desired_action`) instead of the original noun.
Mir Borrowck: Parity with Ast for E0384 (Cannot assign twice to immutable)
- Closes#45199
- Don't allow assigning to dropped immutable variables
- Show the "first assignment" note on the first assignment that can actually come before the second assignment.
- Make "first assignment" notes point to function parameters if needed.
- Don't show a "first assignment" note if the first and second assignment have the same span (in a loop). This matches ast borrowck for now, but maybe this we should add "in previous loop iteration" as with some other borrowck errors. (Commit 2)
- Use revisions to check mir borrowck for the existing tests for this error. (Commit 3)
~~Still working on a less ad-hoc way to get 'first assignment' notes to show on the correct assignment. Also need to check mutating function arguments.~~ Now using a new dataflow pass.
Make accesses to fields of packed structs unsafe
To handle packed structs with destructors (which you'll think are a rare
case, but the `#[repr(packed)] struct Packed<T>(T);` pattern is
ever-popular, which requires handling packed structs with destructors to
avoid monomorphization-time errors), drops of subfields of packed
structs should drop a local move of the field instead of the original
one.
That's it, I think I'll use a strategy suggested by @Zoxc, where this mir
```
drop(packed_struct.field)
```
is replaced by
```
tmp0 = packed_struct.field;
drop tmp0
```
cc #27060 - this should deal with that issue after codegen of drop glue
is updated.
The new errors need to be changed to future-compatibility warnings, but
I'll rather do a crater run first with them as errors to assess the
impact.
cc @eddyb
Things which still need to be done for this:
- [ ] - handle `repr(packed)` structs in `derive` the same way I did in `Span`, and use derive there again
- [ ] - implement the "fix packed drops" pass and call it in both the MIR shim and validated MIR pipelines
- [ ] - do a crater run
- [ ] - convert the errors to compatibility warnings
mention nightly in -Z external-macro-backtrace note
Fix#46167 by mentioning that you need nightly in the message that tells you to pass `-Z external-macro-backtrace`.
Rationale:
1. The reason for having this message is to increase discoverability of the functionality. If the message is only shown on nightly it's less disoverable.
2. The same approach is taken if you call a const fn in const context without its feature gate (previously, if you called it without `#![feature(const_fn)]`).
cc @kennytm
MIR: adopt borrowck test
Fix trailing whitespace
span_bug! on unexpected action
Make RegionVid use newtype_index!
Closes#45843
Check rvalue aggregates during check_stmt in tycheck, add initial, (not passing) test
Fix failing test
Remove attributes and test comments accidentally left behind, add in span_mirbugs
Normalize LvalueTy for ops and format code to satisfy tidy check
only normalize operand types when in an ADT constructor
avoid early return
handle the active field index in unions
normalize types in ADT constructor
Fixes#45940
Fix borrowck compiler errors for upvars contain "spurious" dereferences
Fixes#46003
added associated function Box::leak
Box::leak - improve documentation
Box::leak - fixed bug in documentation
Box::leak - relaxed constraints wrt. lifetimes
Box::leak - updated documentation
Box::leak - made an oops, fixed now =)
Box::leak: update unstable issue number (46179).
Add test for #44953
Add missing Debug impls to std_unicode
Also adds #![deny(missing_debug_implementations)] so they don't get
missed again.
Amend RELEASES for 1.22.1
and fix the date for 1.22.0
Rename param in `[T]::swap_with_slice` from `src` to `other`.
The idea of ‘source’ and ‘destination’ aren’t very applicable for this
operation since both slices can both be considered sources and
destinations.
Clarify stdin behavior of `Command::output`.
Fixes#44929.
Add hints for the case of confusing enum with its variants
Add failing testcases
Add module population and case of enum in place of expression
Use for_each_child_stable in find_module
Use multiline text for crate conflict diagnostics
Make float::from_bits transmute (and update the documentation to reflect this).
The current implementation/documentation was made to avoid sNaN because of
potential safety issues implied by old/bad LLVM documentation. These issues
aren't real, so we can just make the implementation transmute (as permitted
by the existing documentation of this method).
Also the documentation didn't actually match the behaviour: it said we may
change sNaNs, but in fact we canonicalized *all* NaNs.
Also an example in the documentation was wrong: it said we *always* change
sNaNs, when the documentation was explicitly written to indicate it was
implementation-defined.
This makes to_bits and from_bits perfectly roundtrip cross-platform, except
for one caveat: although the 2008 edition of IEEE-754 specifies how to
interpet the signaling bit, earlier editions didn't. This lead to some platforms
picking the opposite interpretation, so all signaling NaNs on x86/ARM are quiet
on MIPS, and vice-versa.
NaN-boxing is a fairly important optimization, while we don't even guarantee
that float operations properly preserve signalingness. As such, this seems like
the more natural strategy to take (as opposed to trying to mangle the signaling
bit on a per-platform basis).
This implementation is also, of course, faster.
Simplify an Iterator::fold to Iterator::any
This method of once-diagnostics doesn't allow nesting
UI tests extract the regular output from the 'rendered' field in json
Merge cfail and ui tests into ui tests
Add a MIR pass to lower 128-bit operators to lang item calls
Runs only with `-Z lower_128bit_ops` since it's not hooked into targets yet.
Include tuple projections in MIR tests
Add type checking for the lang item
As part of doing so, add more lang items instead of passing u128 to the i128 ones where it doesn't matter in twos-complement.
Handle shifts properly
* The overflow-checking shift items need to take a full 128-bit type, since they need to be able to detect idiocy like `1i128 << (1u128 << 127)`
* The unchecked ones just take u32, like the `*_sh?` methods in core
* Because shift-by-anything is allowed, cast into a new local for every shift
incr.comp.: Make sure we don't lose unused green results from the query cache.
rustbuild: Update LLVM and enable ThinLTO
This commit updates LLVM to fix#45511 (https://reviews.llvm.org/D39981) and
also reenables ThinLTO for libtest now that we shouldn't hit #45768. This also
opportunistically enables ThinLTO for libstd which was previously blocked
(#45661) on test failures related to debuginfo with a presumed cause of #45511.
Closes#45511
std: Flag Windows TLS dtor symbol as #[used]
Turns out ThinLTO was internalizing this symbol and eliminating it. Worse yet if
you compiled with LTO turns out no TLS destructors would run on Windows! The
`#[used]` annotation should be a more bulletproof implementation (in the face of
LTO) of preserving this symbol all the way through in LLVM and ensuring it makes
it all the way to the linker which will take care of it.
Add enum InitializationRequiringAction
Fix tidy tests
Include enclosing span when suggesting dereference on a span that is
already a reference:
```
error: non-reference pattern used to match a reference (see issue #42640)
--> dont-suggest-dereference-on-arg.rs:16:19
|
16 | .filter(|&(ref a, _)| foo(a))
| ^^^^^^^^^^^ help: consider using: `&&(ref k, _)`
|
= help: add #![feature(match_default_bindings)] to the crate attributes to enable
```
Add hints for the case of confusing enum with its variants
A solution for https://github.com/rust-lang/rust/issues/43871. When one uses an enum in a place that accepts variants (e.g., `Option(result)` instead of `Some(result)`), suggest one of this enum's variants.
cc @estebank
Implement in-band lifetime bindings
TODO (perhaps in a future PR): Should we ban explicit instantiation of generics with in-band lifetimes, or is it uncontroversial to just append them to the end of the lifetimes list?
Fixes#46042, cc #44524.
r? @nikomatsakis
Use the proper term when using non-existing variant
When using a non-existing variant, function or associated item, refer to
the proper term, instead of defaulting to "associated item" in
diagnostics.
Fix#28972.
```
error[E0599]: no variant named `Quux` found for type `Foo` in the current scope
--> file.rs:7:9
|
7 | Foo::Quux(..) =>(),
| ^^^^^^^^^^^^^
```
Prevent fmt::Arguments from being shared across threads
Fixes#45197
This is a **breaking change**! Without doing this it's very easy to create race conditions.
There's probably a way to do this without breaking valid use cases, but it would require quite an overhaul of the formatting machinery.
MIR-borrowck: Some minor fixes
- Remove parens when printing dereference (fix#45185)
- Change argument type of `autoderef` to `bool`
- Change argument type of `field_index` to `Field`
move closure kind, signature into `ClosureSubsts`
Instead of using side-tables, store the closure-kind and signature in the substitutions themselves. This has two key effects:
- It means that the closure's type changes as inference finds out more things, which is very nice.
- As a result, it avoids the need for the `freshen_closure_like` code (though we still use it for generators).
- It avoids cyclic closures calls.
- These were never meant to be supported, precisely because they make a lot of the fancy inference that we do much more complicated. However, due to an oversight, it was previously possible -- if challenging -- to create a setup where a closure *directly* called itself (see e.g. #21410).
We have to see what the effect of this change is, though. Needs a crater run. Marking as [WIP] until that has been assessed.
r? @arielb1
impl Trait Lifetime Handling
This PR implements the updated strategy for handling `impl Trait` lifetimes, as described in [RFC 1951](https://github.com/rust-lang/rfcs/blob/master/text/1951-expand-impl-trait.md) (cc #42183).
With this PR, the `impl Trait` desugaring works as follows:
```rust
fn foo<T, 'a, 'b, 'c>(...) -> impl Foo<'a, 'b> { ... }
// desugars to
exists type MyFoo<ParentT, 'parent_a, 'parent_b, 'parent_c, 'a, 'b>: Foo<'a, 'b>;
fn foo<T, 'a, 'b, 'c>(...) -> MyFoo<T, 'static, 'static, 'static, 'a, 'b> { ... }
```
All of the in-scope (parent) generics are listed as parent generics of the anonymous type, with parent regions being replaced by `'static`. Parent regions referenced in the `impl Trait` return type are duplicated into the anonymous type's generics and mapped appropriately.
One case came up that wasn't specified in the RFC: it's possible to write a return type that contains multiple regions, neither of which outlives the other. In that case, it's not clear what the required lifetime of the output type should be, so we generate an error.
There's one remaining FIXME in one of the tests: `-> impl Foo<'a, 'b> + 'c` should be able to outlive both `'a` and `'b`, but not `'c`. Currently, it can't outlive any of them. @nikomatsakis and I have discussed this, and there are some complex interactions here if we ever allow `impl<'a, 'b> SomeTrait for AnonType<'a, 'b> { ... }`, so the plan is to hold off on this until we've got a better idea of what the interactions are here.
cc #34511.
Fixes#44727.
show macro backtrace with -Z flag
Fixes#39413 by adding a facility to restore the "old school" macro expansion backtraces (previously removed in 61865384b8).
The restored functionality is accessed through the flag `-Z external-macro-backtrace`. Errors showing the truncated backtraces will suggest this flag.
### Example
Code: <details>
`a/src/lib.rs`
```rust
#[macro_export]
macro_rules! a {
() => { a!(@) };
(@) => { a!(@@) };
(@@) => {
syntax error;
}
}
```
`b/src/main.rs`
```rust
#[macro_use] extern crate a;
macro_rules! b {
() => { b!(@) };
(@) => { b!(@@) };
(@@) => {
syntax error;
}
}
fn main() {
a!();
b!();
}
```
</details>
<br/><br/>
Running without env var (note: first error is from remote macro, second from local macro):
<details>
```
$ cargo +custom run
Compiling b v0.1.0
error: expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found `error`
--> src/main.rs:12:5
|
12 | a!();
| ^^^^^
| |
| expected one of 8 possible tokens here
| unexpected token
|
= note: this error originates in a macro outside of the current crate (run with RUST_MACRO_BACKTRACE=1 for more info)
error: expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found `error`
--> src/main.rs:7:16
|
7 | syntax error;
| -^^^^^ unexpected token
| |
| expected one of 8 possible tokens here
...
13 | b!();
| ----- in this macro invocation
error: aborting due to 2 previous errors
error: Could not compile `b`.
To learn more, run the command again with --verbose.
```
</details>
The output is the same as today, except for an addition to the note which aids discoverability of the new environment variable.
<br/><br/>
Running _with_ env var:
<details>
```
$ RUST_MACRO_BACKTRACE=1 cargo +custom run
Compiling b v0.1.0
error: expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found `error`
--> <a macros>:1:72
|
1 | ( ) => { a ! ( @ ) } ; ( @ ) => { a ! ( @ @ ) } ; ( @ @ ) => { syntax error ;
| -^^^^^ unexpected token
| |
| expected one of 8 possible tokens here
src/main.rs:12:5: 12:10 note: in this expansion of a! (defined in <a macros>)
<a macros>:1:11: 1:20 note: in this expansion of a! (defined in <a macros>)
<a macros>:1:36: 1:47 note: in this expansion of a! (defined in <a macros>)
error: expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found `error`
--> src/main.rs:7:16
|
7 | syntax error;
| -^^^^^ unexpected token
| |
| expected one of 8 possible tokens here
src/main.rs:12:5: 12:10 note: in this expansion of a! (defined in <a macros>)
<a macros>:1:11: 1:20 note: in this expansion of a! (defined in <a macros>)
<a macros>:1:36: 1:47 note: in this expansion of a! (defined in <a macros>)
error: expected one of `!`, `.`, `::`, `;`, `?`, `{`, `}`, or an operator, found `error`
--> src/main.rs:7:16
|
7 | syntax error;
| -^^^^^ unexpected token
| |
| expected one of 8 possible tokens here
src/main.rs:13:5: 13:10 note: in this expansion of b! (defined in src/main.rs)
src/main.rs:4:13: 4:18 note: in this expansion of b! (defined in src/main.rs)
src/main.rs:5:14: 5:20 note: in this expansion of b! (defined in src/main.rs)
error: aborting due to 2 previous errors
error: Could not compile `b`.
To learn more, run the command again with --verbose.
```
</details>
The output is hard to read, but better than nothing (and it's exactly what we used to have before the infamous `fix_multispans_in_std_macros`).
<br/><br/>
Wishlist:
- Save the actual source of macros in crate metadata, not just AST, so the output can be improved
- Hopefully this would allow line numbers in the trace as well
- Show the actual macro invocations in the traces
r? @nrc
