There are several indications that we should not ZST as a ScalarInt:
- We had two ways to have ZST valtrees, either an empty `Branch` or a `Leaf` with a ZST in it.
`ValTree::zst()` used the former, but the latter could possibly arise as well.
- Likewise, the interpreter had `Immediate::Uninit` and `Immediate::Scalar(Scalar::ZST)`.
- LLVM codegen already had to special-case ZST ScalarInt.
So instead add new ZST variants to those types that did not have other variants
which could be used for this purpose.
Rollup merge of #98350 - pcwalton:dwarf5, r=michaelwoerister
Implement support for DWARF version 5.
DWARF version 5 brings a number of improvements over version 4. Quoting from
the announcement [1]:
> Version 5 incorporates improvements in many areas: better data compression,
> separation of debugging data from executable files, improved description of
> macros and source files, faster searching for symbols, improved debugging
> optimized code, as well as numerous improvements in functionality and
> performance.
On platforms where DWARF version 5 is supported (Linux, primarily), this commit
adds support for it behind a new `-Z dwarf-version=5` flag.
Auto merge of #98816 - estebank:implicit-sized, r=oli-obk
Track implicit `Sized` obligations in type params
When we evaluate `ty::GenericPredicates` we introduce the implicit
`Sized` predicate of type params, but we do so with only the `Predicate`
its `Span` as context, we don't have an `Obligation` or
`ObligationCauseCode` we could influence. To try and carry this
information through, we add a new field to `ty::GenericPredicates` that
tracks both which predicates come from a type param and whether that
param has any bounds already (to use in suggestions).
We also suggest adding a `?Sized` bound if appropriate on E0599.
When deriving functions for zero-variant enums, we just generated a
function body that calls `std::instrincs::unreachable`. There is a large
comment with some not-very-useful historical discussion about
alternatives, including some discussion of feature-gating zero-variant
enums, which is clearly irrelevant today.
The deriving code has some complex parts involving iterations over
selflike args and also fields within structs and enum variants.
The return types for a few functions demonstrate this:
- `TraitDef::create_{struct_pattern,enum_variant_pattern}` returns a
`(P<ast::Pat>, Vec<(Span, Option<Ident>, P<Expr>)>)`
- `TraitDef::create_struct_field_accesses` returns a `Vec<(Span,
Option<Ident>, P<Expr>)>`.
This results in per-field data stored within per-selflike-arg data, with
lots of repetition within the per-field data elements. This then has to
be "transposed" in two places (`expand_struct_method_body` and
`expand_enum_method_body`) into per-self-like-arg data stored within
per-field data. It's all quite clumsy and confusing.
This commit rearranges things greatly. Data is obtained in the needed
form up-front, avoiding the need for transposition. Also, various
functions are split, removed, and added, to make things clearer and
avoid tuple return values.
The diff is hard to read, which reflects the messiness of the original
code -- there wasn't an easy way to break these changes into small
pieces. (Sorry!) It's a net reduction of 35 lines and a readability
improvement. The generated code is unchanged.
The deriving code has inconsistent terminology to describe args.
In some places it distinguishes between:
- the `&self` arg (if present), versus
- all other args.
In other places it distinguishes between:
- the `&self` arg (if present) and any other arguments with the same
type (in practice there is at most one, e.g. in `PartialEq::eq`),
versus
- all other args.
The terms "self_args" and "nonself_args" are sometimes used for the
former distinction, and sometimes for the latter. "args" is also
sometimes used for "all other args".
This commit makes the code consistently uses "self_args"/"nonself_args"
for the former and "selflike_args"/"nonselflike_args" for the latter.
This change makes the code easier to read.
The commit also adds a panic on an impossible path (the `Self_` case) in
`extract_arg_details`.
Patrick Walton [Mon, 20 Jun 2022 23:26:51 +0000 (16:26 -0700)]
Implement support for DWARF version 5.
DWARF version 5 brings a number of improvements over version 4. Quoting from
the announcement [1]:
> Version 5 incorporates improvements in many areas: better data compression,
> separation of debugging data from executable files, improved description of
> macros and source files, faster searching for symbols, improved debugging
> optimized code, as well as numerous improvements in functionality and
> performance.
On platforms where DWARF version 5 is supported (Linux, primarily), this commit
adds support for it behind a new `-Z dwarf-version=5` flag.
Auto merge of #98614 - oli-obk:take_unsound_opaque_types, r=wesleywiser
don't succeed `evaluate_obligation` query if new opaque types were registered
fixes #98608
fixes #98604
The root cause of all this is that in type flag computation we entirely ignore nongeneric things like struct fields and the signature of function items. So if a flag had to be set for a struct if it is set for a field, that will only happen if the field is generic, as only the generic parameters are checked.
I now believe we cannot use type flags to handle opaque types. They seem like the wrong tool for this.
Instead, this PR replaces the previous logic by adding a new variant of `EvaluatedToOk`: `EvaluatedToOkModuloOpaqueTypes`, which says that there were some opaque types that got hidden types bound, but that binding may not have been legal (because we don't know if the opaque type was in its defining scope or not).
Rollup merge of #98533 - jyn514:drop-tracking-debugging, r=eholk
Add a `-Zdump-drop-tracking-cfg` debugging flag
This is useful for debugging drop-tracking; previously, you had to recompile
rustc from source and manually add a call to `write_graph_to_file`. This
makes the option more discoverable and configurable at runtime.
I also took the liberty of making the labels for the CFG nodes much easier to read:
previously, they looked like `id(2), local_id: 48`, now they look like
```
expr from_config (hir_id=HirId { owner: DefId(0:10 ~ default_struct_update[79f9]::foo), local_id: 2})
```
Auto merge of #98758 - nnethercote:more-derive-output-improvements, r=Mark-Simulacrum
More derive output improvements
This PR includes:
- Some test improvements.
- Some cosmetic changes to derive output that make the code look more like what a human would write.
- Some more fundamental improvements to `cmp` and `partial_cmp` generation.
Auto merge of #98638 - bjorn3:less_string_interning, r=tmiasko
Use less string interning
This removes string interning in a couple of places where doing so won't result in perf improvements. I also switched one place to use pre-interned symbols.
Auto merge of #99047 - matthiaskrgr:rollup-01vn70s, r=matthiaskrgr
Rollup of 6 pull requests
Successful merges:
- #95635 (sess: stabilize `--terminal-width` as `--diagnostic-width`)
- #98718 (Stabilize `into_future`)
- #98795 (A few cleanups)
- #98798 (Fix caching bug in `download-rustc = true`)
- #99019 (Add doc comments in `rustc_middle::mir`)
- #99026 (Add test for and fix rust-lang/rust-clippy#9131)
Rollup merge of #98798 - jyn514:download-rustc-cached, r=Mark-Simulacrum
Fix caching bug in `download-rustc = true`
When moving this to rustbuild, I introduced a bug: if you had the file already downloaded, but
deleted the sysroot for whatever reason, rustbuil would fail to unpack the cached tarball.
This only affects people if they have a cached tarball, which is probably why we haven't seen an issue yet -
wiping `build/cache` would work around the issue, or just not deleting `build/$TARGET/stage2`.
Fixes the following error:
```
thread 'main' panicked at 'fs::read_dir(&lib_dir) failed with No such file or directory (os error 2) ("/home/jnelson/rust-lang/rust2/build/x86_64-unknown-linux-gnu/ci-rustc/lib")', config.rs:1563:20
```
Rollup merge of #98718 - yoshuawuyts:stabilize-into-future, r=yaahc
Stabilize `into_future`
https://github.com/rust-lang/rust/issues/67644 has been labeled with [S-tracking-ready-to-stabilize](https://github.com/rust-lang/rust/labels/S-tracking-ready-to-stabilize) - which mentions someone needs to file a stabilization PR. So hence this PR! :sparkles: Thanks!
Rollup merge of #95635 - davidtwco:terminal-width-stabilization, r=oli-obk
sess: stabilize `--terminal-width` as `--diagnostic-width`
Formerly `-Zterminal-width`, `--terminal-width` allows the user or build
tool to inform rustc of the width of the terminal so that diagnostics
can be truncated.
Pending agreement to stabilize, see tracking issue at #84673.
Auto merge of #98360 - estebank:uninit-binding, r=oli-obk
On partial uninit error point at where we need init
When a binding is declared without a value, borrowck verifies that all
codepaths have *one* assignment to them to initialize them fully. If
there are any cases where a condition can be met that leaves the binding
uninitialized or we attempt to initialize a field of an uninitialized
binding, we emit E0381.
We now look at all the statements that initialize the binding, and use
them to explore branching code paths that *don't* and point at them. If
we find *no* potential places where an assignment to the binding might
be missing, we display the spans of all the existing initializers to
provide some context.
Auto merge of #99024 - matthiaskrgr:rollup-8ygpcpg, r=matthiaskrgr
Rollup of 9 pull requests
Successful merges:
- #97917 (Implement ExitCodeExt for Windows)
- #98844 (Reword comments and rename HIR visiting methods.)
- #98979 (interpret: use AllocRange in UninitByteAccess)
- #98986 (Fix missing word in comment)
- #98994 (replace process exit with more detailed exit in src/bootstrap/*.rs)
- #98995 (Add a test for #80471)
- #99002 (suggest adding a derive for #[default] applied to variants)
- #99004 (Add a test for #70408)
- #99017 (Replace boolean argument for print_where_clause with an enum to make code more clear)
Esteban Küber [Tue, 21 Jun 2022 18:57:45 +0000 (11:57 -0700)]
On partial uninit error point at where we need init
When a binding is declared without a value, borrowck verifies that all
codepaths have *one* assignment to them to initialize them fully. If
there are any cases where a condition can be met that leaves the binding
uninitialized or we attempt to initialize a field of an unitialized
binding, we emit E0381.
We now look at all the statements that initialize the binding, and use
them to explore branching code paths that *don't* and point at them. If
we find *no* potential places where an assignment to the binding might
be missing, we display the spans of all the existing initializers to
provide some context.
I implemeted "detail_exit.rs" in lib.rs, and replace all of std::process::exit.
So, error code should panic in test code.
```
// lib.rs
pub fn detail_exit(code: i32) -> ! {
// Successful exit
if code == 0 {
std::process::exit(0);
}
if cfg!(test) {
panic!("status code: {}", code);
} else {
std::panic::resume_unwind(Box::new(code));
}
}
```
Rollup merge of #98844 - cjgillot:deep-visit, r=jyn514
Reword comments and rename HIR visiting methods.
Sparked by this discussion in [zulip](https://rust-lang.zulipchat.com/#narrow/stream/182449-t-compiler.2Fhelp/topic/Confused.20by.20comment.20on.20.60deep_visit_item_likes_in_module.60)
Rollup merge of #97917 - AronParker:master, r=ChrisDenton
Implement ExitCodeExt for Windows
Fixes #97914
### Motivation:
On Windows it is common for applications to return `HRESULT` (`i32`) or `DWORD` (`u32`) values. These stem from COM based components ([HRESULTS](https://docs.microsoft.com/en-us/windows/win32/api/objbase/nf-objbase-coinitialize)), Win32 errors ([GetLastError](https://docs.microsoft.com/en-us/windows/win32/api/errhandlingapi/nf-errhandlingapi-getlasterror)), GUI applications ([WM_QUIT](https://docs.microsoft.com/en-us/windows/win32/winmsg/wm-quit)) and more. The newly stabilized `ExitCode` provides an excellent fit for propagating these values, because `std::process::exit` does not run deconstructors which can result in errors. However, `ExitCode` currently only implements `From<u8> for ExitCode`, which disallows the full range of `i32`/`u32` values. This pull requests attempts to address that shortcoming by providing windows specific extensions that accept a `u32` value (which covers all possible `HRESULTS` and Win32 errors) analog to [ExitStatusExt::from_raw](https://doc.rust-lang.org/std/os/windows/process/trait.ExitStatusExt.html#tymethod.from_raw).
This was also intended by the original Stabilization https://github.com/rust-lang/rust/pull/93840#issue-1129209143= as pointed out by ``@eggyal`` in https://github.com/rust-lang/rust/issues/97914#issuecomment-1151076755:
> Issues around platform specific representations: We resolved this issue by changing the return type of report from i32 to the opaque type ExitCode. __That way we can change the underlying representation without affecting the API, letting us offer full support for platform specific exit code APIs in the future.__
[Emphasis added]
### API
```rust
/// Windows-specific extensions to [`process::ExitCode`].
///
/// This trait is sealed: it cannot be implemented outside the standard library.
/// This is so that future additional methods are not breaking changes.
#[stable(feature = "windows_process_exit_code_from", since = "1.63.0")]
pub trait ExitCodeExt: Sealed {
/// Creates a new `ExitCode` from the raw underlying `u32` return value of
/// a process.
#[stable(feature = "windows_process_exit_code_from", since = "1.63.0")]
fn from_raw(raw: u32) -> Self;
}
I apologize in advance if I misplaced any attributes regarding stabilzation, as far as I learned traits are insta-stable so I chose to make them stable. If this is an error, please let me know and I'll correct it. I also added some additional machinery to make it work, analog to [ExitStatus](https://doc.rust-lang.org/std/process/struct.ExitStatus.html#).
Auto merge of #95573 - cjgillot:lower-query, r=michaelwoerister
Make lowering a query
Split from https://github.com/rust-lang/rust/pull/88186.
This PR refactors the relationship between lowering and the resolver outputs in order to make lowering itself a query.
In a first part, lowering is changed to avoid modifying resolver outputs, by maintaining its own data structures for creating new `NodeId`s and so.
Then, the `TyCtxt` is modified to allow creating new `LocalDefId`s from inside it. This is done by:
- enclosing `Definitions` in a lock, so as to allow modification;
- creating a query `register_def` whose purpose is to declare a `LocalDefId` to the query system.
See `TyCtxt::create_def` and `TyCtxt::iter_local_def_id` for more detailed explanations of the design.
Rollup merge of #98930 - tmiasko:pub-basic-blocks, r=oli-obk
Make MIR basic blocks field public
This makes it possible to mutably borrow different fields of the MIR
body without resorting to methods like `basic_blocks_local_decls_mut_and_var_debug_info`.
To preserve validity of control flow graph caches in the presence of
modifications, a new struct `BasicBlocks` wraps together basic blocks
and control flow graph caches.
The `BasicBlocks` dereferences to `IndexVec<BasicBlock, BasicBlockData>`.
On the other hand a mutable access requires explicit `as_mut()` call.
Rollup merge of #98901 - davidtwco:split-dwarf-incr-workproduct, r=michaelwoerister
incr: cache dwarf objects in work products
Cache DWARF objects alongside object files in work products when those exist so that DWARF object files are available for thorin in packed mode in incremental scenarios.
Rollup merge of #98507 - xFrednet:rfc-2383-manual-expectation-magic, r=wesleywiser
Finishing touches for `#[expect]` (RFC 2383)
This PR adds documentation and some functionality to rustc's lint passes, to manually fulfill expectations. This is needed for some lints in Clippy. Hopefully, it should be one of the last things before we can move forward with stabilizing this feature.
As part of this PR, I've also updated `clippy::duplicate_mod` to showcase how this new functionality can be used and to ensure that it works correctly.
Auto merge of #98675 - eddyb:cg-array-literal, r=nikic
rustc_codegen_ssa: use `project_index`, not `project_field`, for array literals.
See https://github.com/rust-lang/rust/pull/98615#issuecomment-1170082774 for some context.
In short, we were using `project_field` even for array `mir::Rvalue::Aggregate`s, which results in benchmarks like `deep-vector.rs` (and presumably also some real-world usecases?) being impacted by how we handle non-array aggregate fields.
(This is a separate PR so that we can measure the perf effects in isolation)
Oli Scherer [Thu, 7 Jul 2022 08:10:50 +0000 (08:10 +0000)]
not knowing about opaque types is worse than not knowing about regions, make sure we don't accidentally mark something as ok-modulo-regions if there are opaque types involved