mGCA: Make trait object types with type-level associated consts dyn compatible
Under feature `min_generic_const_args` (mGCA) (rust-lang/rust#132980), render traits with non-parametrized type-level associated constants (i.e., `#[type_const]` ones) dyn compatible but force the user to specify all type-level associated consts in the trait object type via bindings (either directly, via supertrait bounds and/or behind trait aliases) just like associated types, their sibling.
Fixesrust-lang/rust#130300 (feature request).
Fixesrust-lang/rust#136063 (bug).
Fixesrust-lang/rust#137260 (bug).
Fixesrust-lang/rust#137514 (bug).
While I'm accounting for most illegal `Self` references via const projections & params, I'm intentionally ignoring RUST-123140 (and duplicates) in this PR which is to be tackled some other time.
Additional context: Crate `rustc-demangle` had to be updated to fix v0 demangling. I've patched it in PR https://github.com/rust-lang/rustc-demangle/pull/87 which was was released in version 0.1.27 via PR https://github.com/rust-lang/rustc-demangle/pull/88.
So that when we later add support for revisions we can use the same
syntax for revisions as elsewhere.
This also prevents people from making typos for commands since
`src/tools/compiletest/src/directives/directive_names.rs` will catch such
typos now.
Note that we one FIXME for a non-trivial change for later:
```
// FIXME(148097): Change `// cdb-checksimple_closure` to `//@ cdb-check:simple_closure`
```
Rust's current mangling scheme depends on compiler internals; loses
information about generic parameters (and other things) which makes for
a worse experience when using external tools that need to interact with
Rust symbol names; is inconsistent; and can contain `.` characters
which aren't universally supported. Therefore, Rust has defined its own
symbol mangling scheme which is defined in terms of the Rust language,
not the compiler implementation; encodes information about generic
parameters in a reversible way; has a consistent definition; and
generates symbols that only use the characters `A-Z`, `a-z`, `0-9`, and
`_`.
Support for the new Rust symbol mangling scheme has been added to
upstream tools that will need to interact with Rust symbols (e.g.
debuggers).
This commit changes the default symbol mangling scheme from the legacy
scheme to the new Rust mangling scheme.
Signed-off-by: David Wood <david.wood@huawei.com>
To make debugger stepping intuitive with `-Copt-level=0`. See the
adjusted `basic-stepping.rs` test.
This is kind of a revert of bd0aae92dc, except we don't revert it,
we just make it conditional on `opt-level`. That commit regressed
`basic-stepping.rs`, but it was not noticed since that test did not
exist back then. I have retroactively bisected to find that out.
It seems messy to sprinkle if-cases inside of the
`write_operand_repeatedly()` so make the whole function conditional.
The test that bd0aae92dc added in
`tests/codegen/issues/issue-111603.rs` already use `-Copt-level=3`, so
we don't need to adjust the compiler flags for it to keep passing.
While looking at the pretty-printers, I found a few minor oddities in
StdNonZeroNumberProvider.
First, gdb.Type.fields() already returns a sequence, so there's no
need to call list().
Second, it's more idiomatic for the (somewhat misnamed) to_string
method to simply return the underlying gdb.Value. This also lets gdb
apply whatever formats were passed to `print`, as the new test shows.
Third, there's no need to use the field's name when looking up a field
in a value, the gdb.Field itself can be used.
tests: activate misspelled `gdb-check` in `function-arg-initialization.rs`
In 9253e1206e a bunch of `gdbr-check` (for `rust-gdb`) directives and `gdbg-check` (for plain `gdb`) directives were added. But in two places the author accidentally wrote `gdbt-check` instead (`t` is next to `r` on the keyboard). This commit fixes that typo.
rust-lang/rust#129218 later renamed `gdbr-check` to just `gdb-check` which is why we rename to `gdb-check` directly.
The test still passes locally for me after the change, but fails if I change the `gdb-check` checks to check for some other string, so the check seems to still perform its intended function.
Note that we need to add a `std::hint::black_box()` to avoid
$4 = <optimized out>
prints on at least `aarch64-gnu-llvm-20-1`.
After this there are no more instances of the string `gdbt` in the code base:
```console
$ git grep gdbt
```
try-job: dist-i586-gnu-i586-i686-musl
In 9253e1206e a bunch of `gdbr-check` (for `rust-gdb`) and
`gdbg-check` (for plain `gdb`) was added. But in two places the author
accidentally wrote `gdbt-check` instead. This commit fixes this typo.
[Debuginfo] improve enum value formatting in LLDB for better readability
> TL;DR: When debugging with CodeLLDB, I noticed enum values were often hard to read because LLDB lists every possible variant, resulting in a verbose and cluttered view, even though only one variant is actually valid. Interestingly, raw enum types display nicely. After some investigation, I found that `&enum` values get classified as `Other`, so it falls back to `DefaultSyntheticProvider`, which causes this verbose output.
## What does this PR do?
This PR contains 2 commits:
1. change the enum value formatting from showing 2 separate fields (`value` for attached data and `$discr$` for the discriminator) to a concise `<readable variant name>: <attached data>` format
2. dereference pointer types in `classify_rust_type` so that it can return more accurate type for reference type
## Self-test proof
Before:
<img width="1706" height="799" alt="before" src="https://github.com/user-attachments/assets/b66c7e22-990a-4da5-9036-34e3f9f62367" />
After:
<img width="1541" height="678" alt="after" src="https://github.com/user-attachments/assets/36db32e2-f822-4883-8f17-cb8067e509f6" />
fix(debuginfo): handle false positives in overflow check
Fixesrust-lang/rust#144636.
Duplicate wrappers and normal recursive types can lead to false positives.
```rust
struct Recursive {
a: Box<Box<Recursive>>,
}
```
The ADT stack can be:
- `Box<Recursive>`
- `Recursive`
- `Box<Box<Recursive>>` (`Box` now detected as expanding)
We can filter them out by tracing the generic arg back through the stack, as true expanding recursive types must have their expanding arg used as generic arg throughout.
r? ````@wesleywiser````
Instead of collecting pretty printers transitively when building
executables/staticlibs/cdylibs, let the debugger find each crate's
pretty printers via its .debug_gdb_scripts section. This covers the case
where libraries defining custom pretty printers are loaded dynamically.
Disabling loading of pretty printers in the debugger itself is more
reliable. Before this commit the .gdb_debug_scripts section couldn't be
included in dylibs or rlibs as otherwise there is no way to disable the
section anymore without recompiling the entire standard library.
f16 support for PowerPC has issues in LLVM, therefore we need a small
workaround to prevent LLVM from emitting symbols that don't exist for
PowerPC yet.
It also appears that unused by-value non-immedate issue with gdb applies
to PowerPC targets as well, though I've only tested 64-bit Linux targets.
Signed-off-by: Jens Reidel <adrian@travitia.xyz>
Stabilize `repr128`
## Stabilisation report
The `repr128` feature ([tracking issue](https://github.com/rust-lang/rust/issues/56071)) allows the use of `#[repr(u128)]` and `#[repr(i128)]` on enums in the same way that other primitive representations such as `#[repr(u64)]` can be used. For example:
```rust
#[repr(u128)]
enum Foo {
One = 1,
Two,
Big = u128::MAX,
}
#[repr(i128)]
enum Bar {
HasThing(u16) = 42,
HasSomethingElse(i64) = u64::MAX as i128 + 1,
HasNothing,
}
```
This is the final part of adding 128-bit integers to Rust ([RFC 1504](https://rust-lang.github.io/rfcs/1504-int128.html)); all other parts of 128-bit integer support were stabilised in #49101 back in 2018.
From a design perspective, `#[repr(u128)]`/`#[repr(i128)]` function like `#[repr(u64)]`/`#[repr(i64)]` but for 128-bit integers instead of 64-bit integers. The only differences are:
- FFI safety: as `u128`/`i128` are not currently considered FFI safe, neither are `#[repr(u128)]`/`#[repr(i128)]` enums (I discovered this wasn't the case while drafting this stabilisation report, so I have submitted #138282 to fix this).
- Debug info: while none of the major debuggers currently support 128-bit integers, as of LLVM 20 `rustc` will emit valid debuginfo for both DWARF and PDB (PDB makes use of the same natvis that is also used for all enums with fields, whereas DWARF has native support).
Tests for `#[repr(u128)]`/`#[repr(i128)]` enums include:
- [ui/enum-discriminant/repr128.rs](385970f0c1/tests/ui/enum-discriminant/repr128.rs): checks that 128-bit enum discriminants have the correct values.
- [debuginfo/msvc-pretty-enums.rs](385970f0c1/tests/debuginfo/msvc-pretty-enums.rs): checks the PDB debuginfo is correct.
- [run-make/repr128-dwarf](385970f0c1/tests/run-make/repr128-dwarf/rmake.rs): checks the DWARF debuginfo is correct.
Stabilising this feature does not require any changes to the Rust Reference as [the documentation on primitive representations](https://doc.rust-lang.org/nightly/reference/type-layout.html#r-layout.repr.primitive.intro) already includes `u128` and `i128`.
Closes#56071
Closes https://github.com/rust-lang/reference/issues/1368
r? lang
```@rustbot``` label +I-lang-nominated +T-lang
This especially improves the developer experience for long chains
of function calls that span multiple lines, which is common with
builder patterns, chains of iterator/future combinators, etc.
avoid overflow when generating debuginfo for expanding recursive types
Fixes#135093Fixes#121538Fixes#107362Fixes#100618Fixes#115994
The overflow happens because expanding recursive types keep creating new nested types when recurring into sub fields.
I fixed that by returning an empty stub node when expanding recursion is detected.
