MIR-borrowck: Migrate remaining ast diagnostics
This PR migrates all of the remaining diagnostics in `rustc_borrowck` over to `rustc_mir`, exposing them for use by both AST-borrowck and MIR-borrowck.
This should hopefully resolve all remaining cases of diagnostic messages emitted from borrowck under `-Z borrowck-mir` without an origin annotation.
Extend mir dump to dump each region
Building on #44878, implement the feature discussed in #44872.
Through discussions on the WG-nll-gitter, @nikomatsakis and I decided to implement this by extending `dump_mir` and all functions that it calls to take a callback of signature `FnMut(PassWhere, &mut Write) -> io::Result<()>` where `PassWhere` is an enum that represents possible locations that we may want to print out extra data in the process of dumping the MIR.
I'm not particularly wedded to the name `PassWhere`, but I felt that simply calling the enum `Where` wasn't the right thing to name it.
This work depends strongly on #44878, and should be rebased on the final version of that tree, whatever that may be.
MIR-borrowck: gather and signal any move errors
When building up the `MoveData` structure for a given MIR, also accumulate any erroneous actions, and then report all of those errors when the construction is complete.
This PR adds a host of move-related error constructor methods to `trait BorrowckErrors`. I think I got the notes right; but we should plan to audit all of the notes before turning MIR-borrowck on by default.
Fix#44830
Extend `dump_mir` and functions it calls in order to allow callers to
add custom information. We do this by adding an enum `PassWhere` and
an extra argument of type `FnMut(PassWhere, &mut Write) ->
io::Result<()>`. This callback is responsible for printing the extra
information when MIR is dumped at various stages.
For the "nll" pass, use the new mechanism to dump the `Region`
information after the header, but before the control flow graph for
every function.
In the interest of keeping the output somewhat concise, implement
a custom Debug impl for `Region`
Open Questions:
* What should we call what has been called `PassWhere` so far?
MIR borrowck: move span_label to `borrowck_errors.rs`
The calls to `span_label` are moved and factorized for:
* E0503 (`cannot_use_when_mutably_borrowed()`)
* E0506 (`cannot_assign_to_borrowed()`)
Additionnally, the error E0594 (`cannot_assign_static()`) has been factorized between `check_loan.rs` and `borrowc_check.rs`.
Part of #44596
This commit moves the calculation of the `LanguageItems` structure into a
query rather than being calculated before the `TyCtxt` exists, with the eventual
end goal of removing some `CrateStore` methods.
post-rebase: Do not put "(Ast)" suffix in error msg unless passed `-Z borrowck-mir`.
(But unconditionally include "(Mir)" suffix for mir-borrowck errors.)
* Emit `EndRegion` for every code-extent for which we observe a
borrow. To do this, we needed to thread source info back through
to `fn in_scope`, which makes this commit a bit more painful than
one might have expected.
* There is `end_region` emission in `Builder::pop_scope` and in
`Builder::exit_scope`; the first handles falling out of a scope
normally, the second handles e.g. `break`.
* Remove `EndRegion` statements during the erase_regions mir
transformation.
* Preallocate the terminator block, and throw an `Unreachable` marker
on it from the outset. Then overwrite that Terminator as necessary
on demand.
* Instead of marking the scope as needs_cleanup after seeing a
borrow, just treat every scope in the chain as being part of the
diverge_block (after any *one* of them has separately signalled
that it needs cleanup, e.g. due to having a destructor to run).
* Allow for resume terminators to be patched when looking up drop flags.
(In particular, `MirPatch::new` has an explicit code path,
presumably previously unreachable, that patches up such resume
terminators.)
* Make `Scope` implement `Debug` trait.
* Expanded a stray comment: we do not emit StorageDead on diverging
paths, but that end behavior might not be desirable.
Create directory for dump-mir-dir automatically
Fixes#35543 r? @Mark-Simulacrum
@Mark-Simulacrum I know someone else said that they'll work on this, but it has been 3+ weeks and I had nothing to do and wanted to contribute a bit.
I now added the call to automatically create the directory as discussed, but was wondering how you feel about the suggestion to set a default directory, i.e. `target/mir`?
This fixes leakage on panic with arrays & slices. I am using a C-style
for-loop instead of a pointer-based loop because that would be ugly-er
to implement.
Use the trait-environment+type as the key. Note that these
are only invoked on types that live for the entire compilation
(no inference artifacts). We no longer need the various special-case
bits and caches that were in place before.
