Commit Graph
5421 Commits
Author SHA1 Message Date
Nicholas Bishop c684183ed8 Allow accessing abstract class fields (#7379)
In `Convert`, allow forming a value or reference of abstract class type,
but not an initializer.

For now, limit the scope to just `ClassElementAccess` to avoid affecting
tests where I'm unclear if allowing abstract types is correct.
2026-06-17 20:41:08 +00:00
Christopher Di Bella f55ffe5914 Add Iterate to the list of non-Clang operators (#7369)
This allows us to use non-generic C++ range types in Carbon range-for
loops.
2026-06-17 19:13:33 +00:00
Dana Jansens 0f14882dd1 Remove fail_todo_class_with_qualified_rewrite test (#7377)
This test was assuming that we'd allow qualified lookup in rewrite
constraints, but that is not in agreement with the design. The design
says that the LHS of a rewrite must be a member access designator like
`.Member`.
2026-06-17 16:31:26 +00:00
josh11bandJosh L a7f8df0383 Update svg code snippets to reflect changes from #7354 (#7370)
Co-authored-by: Josh L <josh11b@users.noreply.github.com>
2026-06-17 15:13:23 +00:00
Richard Smith c1080b25ae Sync utils/textmate directory to carbon.tmbundle repository. (#7374)
Provide a cut-down repository containing just our textmate bundle, both
for easy installation in general and so that github's linguist in
particular can pick it up and use it for highlighting Carbon files.

The sync_repos script is automatically run by our github workflow
whenever utils/ changes.
2026-06-17 14:00:39 +00:00
Richard Smith 5fc8e1cf3e Textmate grammar: avoid variable-width lookbehind. (#7373)
This is not supported by the textmate parser in github's linguist.

Assisted-by: Gemini via Antigravity
2026-06-17 05:43:44 +00:00
Richard Smith 1106d967df Add support for enum comparisons and bitwise operators (#7356)
If C++ overload resolution selects a builtin operator candidate for an
enum comparison or bitwise operator, provide support for that operator
by generating a corresponding Carbon builtin function. This is
structured to be easily extensible to other C++ builtin overload
candidates if we so choose, but for now the operators defined in the
prelude are doing what we want in most cases.

Bitwise operators on enums produce the same enum type as a result. This
intentionally deviates from C++, where they produce a promoted integral
type.

Assisted-by: Gemini via Antigravity
v0.0.0-0.nightly.2026.06.17
2026-06-16 19:51:11 +00:00
Richard Smith 30b6c22444 Remove comment missed by #7013. (#7365)
This comment reflects a special case that no longer exists.
2026-06-16 16:29:21 +00:00
Dana Jansens d68b3fa912 Don't crash when converting a tuple to type if it contains an ErrorInst (#7352)
The conversion will just produce an ErrorInst output.

Right now I am not sure how to get an ErrorInst into that position, but
with https://github.com/carbon-language/carbon-lang/pull/7364 rejecting
`.Self` we end up with this, and it crashes otherwise.
2026-06-16 13:51:38 +00:00
David Blaikie cf6a89db3f Init vptrs in Carbon initialization of Carbon-derived-from-C++ objects (#7323)
For review convenience, the Clang patch is available as an LLVM Draft PR
here: https://github.com/llvm/llvm-project/pull/202807
2026-06-16 04:50:57 +00:00
David Blaikie 88b3605eac Fix #7289: Add debug info module flags as-needed and verify if already present (#7336)
This avoids duplicate module flags when compiling C++ interop with debug
info.

Assisted-by: Gemini via Antigravity
v0.0.0-0.nightly.2026.06.16
2026-06-16 03:18:05 +00:00
Geoff Romer d13495771a Recover from an empty Label field in debug printing (#7363)
Closes #7361
2026-06-15 22:23:18 +00:00
josh11bandJosh L 988c47631e Update design docs to reflect #6177: C++ Interop: Mapping std::string_view to Core.Str (#7349)
Assisted-by: Gemini via Antigravity

---------

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
2026-06-15 22:19:45 +00:00
Nicholas Bishop f2c94517cc Reland "Fix crash from accessing a Check::Context during lowering (#7335)" (#7359)
In generate_ast.cpp, an `CarbonExternalASTSource` is installed that has
a `Check::Context` pointer. During lowering, this `ExternalASTSource` is
still installed, and using it can cause a crash if the now-invalid
pointer is dereferenced.

Fix by adding a new `ReadOnlyASTSource` in sem_ir, and using that during
lowering.

`CarbonExternalASTSource` now inherits from `ReadOnlyASTSource` to avoid
some code duplication.

In generate_ast.cpp, we now always install a multiplex source, even if
there's only one child source. Clang internally keeps pointers to the
top-level `ExternalASTSource` installed via `setExternalSource`, and
those pointers aren't updated if `setExternalSource` is called again. By
using `MultiplexExternalSemaSource`, we can keep the top-level
`ExternalASTSource` pointer the same, and only update its children.

Using `MultiplexExternalSemaSource` this way requires a new constructor
and a method to modify its child sources; added a new LLVM patch adding
those.

Originally landed in #7335, reverted in #7353 due to ASAN errors.
Changes since original:
* Use LLVM RTTI to make `Lower::Context::Finalize` less brittle.
Add LLVM RTTI to `ReadOnlyASTSource` (and `CarbonExternalASTSource`).
Change Finalize so that instead of just deleting the last multiplex
child source, it erases any multiplex child sources that match
`ReadOnlyASTSource`; this includes `CarbonExternalASTSource` since it's
a subclass.
* Fix ASAN error by updating the `MultiplexExternalSemaSource` earlier
in lowering. It is sometimes accessed during PrepareToLower, so update
it in `Context::GetFileContext` rather than `Context::Finalize`.

Fixes https://github.com/carbon-language/carbon-lang/issues/7142
2026-06-15 20:30:07 +00:00
Dana Jansens c3b6b084d4 Find correct nested rewrite constraints (#7280)
When a facet type contains a rewrite constraint like `.(J.J1).(I.I1)`
the ImplWitnessAccess should only use its RHS value if it's trying to
find `.(J.J1).(I.I1)`. It can't just look at the `.(I.I1)` part or it
may grab the RHS for a similar `.(K.K2).(I.I1)` rewrite.

While it's not possible to write a nested access on the LHS of a rewrite
constraint like `.(J.J1).(I.I1)`, it is possible to construct a facet
type that ends up with that as its rewrite using nested facet types:
```carbon
T:! J where .J1 impls (I where .I1 = ())
```

The access `T.(J.J1).(I.I1)` should evaluate to `()`. The
ImplWitnessAccess evaluation starts by looking for a rewrite of
`.(I.I1)` in the type of the access self, which is `T.(J.J1)`. Then it
looks for `.(I.I1)` in the type of that access self, which is `T`. At
that point it finds the rewrite of `.(J.J1).(I.I1) = ()` and can use the
`()`. However it can also find other rewrites that end in `.(I.I1)`.

To do this correctly, when moving through an ImplWitnessAccess to the
next nested access self, we record the access (interface, element) pair
that we are looking through. And then we require the rewrite constraint
to be prefixed by all of the (interface, element) pairs that we have
recorded.
2026-06-15 18:12:44 +00:00
ed51ba4b1a Update design docs to reflect proposal #4682: The Core.Array type... (#7354)
Also:

- Introduce `buf` so that existing examples using arrays can be updated
to use it.
- Update the examples linked to on the Carbon front page to something
closer to what we expect, moving away from old array syntax. Uses
`slice` though that name hasn't been settled. Updating the SVGs actually
referenced will need to be done as a separate step.
- Update links to the expression operators while I'm touching that
section.

Assisted-by: Gemini via Antigravity

---------

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
Co-authored-by: Nicholas Bishop <nbishop@nbishop.net>
2026-06-15 17:36:06 +00:00
Dana Jansens 3a7b49efaa Add some more test coverage of designators (#7347)
- A test showing we need to search facets in the specific interface of
an access to find a witness
- A test using a `<type> impls ...` constraint from earlier in the same
facet type
- Some tests to show a rewrite constraint from earlier in the same facet
type is not incorrectly used when it's applied to a different facet
- A test of a facet type with a rewrite as the RHS of another rewrite,
and the rewrite there should not leak or access things from the outer
facet type
2026-06-15 14:27:32 +00:00
dependabot[bot] fbf0157998 Bump esbuild from 0.25.12 to 0.28.1 in /utils/vscode in the npm_and_yarn group across 1 directory (#7358)
Bumps the npm_and_yarn group with 1 update in the /utils/vscode
directory: [esbuild](https://github.com/evanw/esbuild).

Updates `esbuild` from 0.25.12 to 0.28.1
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/evanw/esbuild/releases">esbuild's
releases</a>.</em></p>
<blockquote>
<h2>v0.28.1</h2>
<ul>
<li>
<p>Disallow <code>\</code> in local development server HTTP requests (<a
href="https://github.com/evanw/esbuild/security/advisories/GHSA-g7r4-m6w7-qqqr">GHSA-g7r4-m6w7-qqqr</a>)</p>
<p>This release fixes a security issue where HTTP requests to esbuild's
local development server could traverse outside of the serve directory
on Windows using a <code>\</code> backslash character. It happened due
to the use of Go's <code>path.Clean()</code> function, which only
handles Unix-style <code>/</code> characters. HTTP requests with paths
containing <code>\</code> are no longer allowed.</p>
<p>Thanks to <a
href="https://github.com/dellalibera"><code>@​dellalibera</code></a> for
reporting this issue.</p>
</li>
<li>
<p>Add integrity checks to the Deno API (<a
href="https://github.com/evanw/esbuild/security/advisories/GHSA-gv7w-rqvm-qjhr">GHSA-gv7w-rqvm-qjhr</a>)</p>
<p>The previous release of esbuild added integrity checks to esbuild's
npm install script. This release also adds integrity checks to esbuild's
Deno install script. Now esbuild's Deno API will also fail with an error
if the downloaded esbuild binary contains something other than the
expected content.</p>
<p>Note that esbuild's Deno API installs from
<code>registry.npmjs.org</code> by default, but allows the
<code>NPM_CONFIG_REGISTRY</code> environment variable to override this
with a custom package registry. This change means that the esbuild
executable served by <code>NPM_CONFIG_REGISTRY</code> must now match the
expected content.</p>
<p>Thanks to <a
href="https://github.com/sondt99"><code>@​sondt99</code></a> for
reporting this issue.</p>
</li>
<li>
<p>Avoid inlining <code>using</code> and <code>await using</code>
declarations (<a
href="https://redirect.github.com/evanw/esbuild/issues/4482">#4482</a>)</p>
<p>Previously esbuild's minifier sometimes incorrectly inlined
<code>using</code> and <code>await using</code> declarations into
subsequent uses of that declaration, which then fails to dispose of the
resource correctly. This bug happened because inlining was done for
<code>let</code> and <code>const</code> declarations by avoiding doing
it for <code>var</code> declarations, which no longer worked when more
declaration types were added. Here's an example:</p>
<pre lang="js"><code>// Original code
{
  using x = new Resource()
  x.activate()
}
<p>// Old output (with --minify)<br />
new Resource().activate();</p>
<p>// New output (with --minify)<br />
{using e=new Resource;e.activate()}<br />
</code></pre></p>
</li>
<li>
<p>Fix module evaluation when an error is thrown (<a
href="https://redirect.github.com/evanw/esbuild/issues/4461">#4461</a>,
<a
href="https://redirect.github.com/evanw/esbuild/pull/4467">#4467</a>)</p>
<p>If an error is thrown during module evaluation, esbuild previously
didn't preserve the state of the module for subsequent module
references. This was observable if <code>import()</code> or
<code>require()</code> is used to import a module multiple times. The
thrown error is supposed to be thrown by every call to
<code>import()</code> or <code>require()</code>, not just the first.
With this release, esbuild will now throw the same error every time you
call <code>import()</code> or <code>require()</code> on a module that
throws during its evaluation.</p>
</li>
<li>
<p>Fix some edge cases around the <code>new</code> operator (<a
href="https://redirect.github.com/evanw/esbuild/issues/4477">#4477</a>)</p>
<p>Previously esbuild incorrectly printed certain edge cases involving
complex expressions inside the target of a <code>new</code> expression
(specifically an optional chain and/or a tagged template literal). The
generated code for the <code>new</code> target was not correctly wrapped
with parentheses, and either contained a syntax error or had different
semantics. These edge cases have been fixed so that they now correctly
wrap the <code>new</code> target in parentheses. Here is an example of
some affected code:</p>
<pre lang="js"><code>// Original code
new (foo()`bar`)()
new (foo()?.bar)()
<p>// Old output<br />
new foo()<code>bar</code>();<br />
new (foo())?.bar();</p>
<p></code></pre></p>
</li>
</ul>
<!-- raw HTML omitted -->
</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/evanw/esbuild/blob/main/CHANGELOG-2025.md">esbuild's
changelog</a>.</em></p>
<blockquote>
<h1>Changelog: 2025</h1>
<p>This changelog documents all esbuild versions published in the year
2025 (versions 0.25.0 through 0.27.2).</p>
<h2>0.27.2</h2>
<ul>
<li>
<p>Allow import path specifiers starting with <code>#/</code> (<a
href="https://redirect.github.com/evanw/esbuild/pull/4361">#4361</a>)</p>
<p>Previously the specification for <code>package.json</code> disallowed
import path specifiers starting with <code>#/</code>, but this
restriction <a
href="https://redirect.github.com/nodejs/node/pull/60864">has recently
been relaxed</a> and support for it is being added across the JavaScript
ecosystem. One use case is using it for a wildcard pattern such as
mapping <code>#/*</code> to <code>./src/*</code> (previously you had to
use another character such as <code>#_*</code> instead, which was more
confusing). There is some more context in <a
href="https://redirect.github.com/nodejs/node/issues/49182">nodejs/node#49182</a>.</p>
<p>This change was contributed by <a
href="https://github.com/hybrist"><code>@​hybrist</code></a>.</p>
</li>
<li>
<p>Automatically add the <code>-webkit-mask</code> prefix (<a
href="https://redirect.github.com/evanw/esbuild/issues/4357">#4357</a>,
<a
href="https://redirect.github.com/evanw/esbuild/issues/4358">#4358</a>)</p>
<p>This release automatically adds the <code>-webkit-</code> vendor
prefix for the <a
href="https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties/mask"><code>mask</code></a>
CSS shorthand property:</p>
<pre lang="css"><code>/* Original code */
main {
  mask: url(x.png) center/5rem no-repeat
}
<p>/* Old output (with --target=chrome110) */<br />
main {<br />
mask: url(x.png) center/5rem no-repeat;<br />
}</p>
<p>/* New output (with --target=chrome110) */<br />
main {<br />
-webkit-mask: url(x.png) center/5rem no-repeat;<br />
mask: url(x.png) center/5rem no-repeat;<br />
}<br />
</code></pre></p>
<p>This change was contributed by <a
href="https://github.com/BPJEnnova"><code>@​BPJEnnova</code></a>.</p>
</li>
<li>
<p>Additional minification of <code>switch</code> statements (<a
href="https://redirect.github.com/evanw/esbuild/issues/4176">#4176</a>,
<a
href="https://redirect.github.com/evanw/esbuild/issues/4359">#4359</a>)</p>
<p>This release contains additional minification patterns for reducing
<code>switch</code> statements. Here is an example:</p>
<pre lang="js"><code>// Original code
switch (x) {
  case 0:
    foo()
    break
  case 1:
  default:
    bar()
}
</code></pre>
</li>
</ul>
<!-- raw HTML omitted -->
</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/evanw/esbuild/commit/bb9db84c02433fbe37b3509f53f9f3e3cc48725e"><code>bb9db84</code></a>
publish 0.28.1 to npm</li>
<li><a
href="https://github.com/evanw/esbuild/commit/9ff053e53b8eeb990f59355dbea365277ac45ee2"><code>9ff053e</code></a>
security: add integrity checks to the Deno API</li>
<li><a
href="https://github.com/evanw/esbuild/commit/0a9bf2135b67c7e28989a5ba19f0f000805a5ab5"><code>0a9bf21</code></a>
enforce non-negative size in gzip parser</li>
<li><a
href="https://github.com/evanw/esbuild/commit/e2a1a7132058ee067fe736eac15f695861b8654e"><code>e2a1a71</code></a>
security: forbid <code>\\</code> in local dev server requests</li>
<li><a
href="https://github.com/evanw/esbuild/commit/83a2cbfc35809f4fd5152da59572d7bed7739d78"><code>83a2cbf</code></a>
fix <a
href="https://redirect.github.com/evanw/esbuild/issues/4482">#4482</a>:
don't inline <code>using</code> declarations</li>
<li><a
href="https://github.com/evanw/esbuild/commit/308ad745d824c77bc607603451b257d0f2fd9a38"><code>308ad74</code></a>
fix <a
href="https://redirect.github.com/evanw/esbuild/issues/4471">#4471</a>:
renaming of nested <code>var</code> declarations</li>
<li><a
href="https://github.com/evanw/esbuild/commit/f013f5f99a015bce92ec48d49181d4ad3177b29b"><code>f013f5f</code></a>
fix some typos</li>
<li><a
href="https://github.com/evanw/esbuild/commit/aafd6e48b1088336a5f5a17e930be7e840d43d8c"><code>aafd6e4</code></a>
chore: fix some minor issues in comments (<a
href="https://redirect.github.com/evanw/esbuild/issues/4462">#4462</a>)</li>
<li><a
href="https://github.com/evanw/esbuild/commit/15300c30b5e22f7cfcbed850c246d35095658386"><code>15300c3</code></a>
follow up: cjs evaluation fixes</li>
<li><a
href="https://github.com/evanw/esbuild/commit/1bda0c31d7697c0af44b3ab39b81e599e559a395"><code>1bda0c3</code></a>
fix <a
href="https://redirect.github.com/evanw/esbuild/issues/4461">#4461</a>,
fix <a
href="https://redirect.github.com/evanw/esbuild/issues/4467">#4467</a>:
esm evaluation fixes</li>
<li>Additional commits viewable in <a
href="https://github.com/evanw/esbuild/compare/v0.25.12...v0.28.1">compare
view</a></li>
</ul>
</details>
<details>
<summary>Maintainer changes</summary>
<p>This version was pushed to npm by <a
href="https://www.npmjs.com/~GitHub%20Actions">GitHub Actions</a>, a new
releaser for esbuild since your current version.</p>
</details>
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v0.0.0-0.nightly.2026.06.15
2026-06-14 22:43:32 +00:00
Geoff RomerandRichard Smith e023f75254 Implement thunking in terms of constant evaluation (#7332)
The bulk of this change is changing most pattern insts to be `Always`
rather than `AlwaysUnique` constants, so that they can be wrapped in
`SpecificConstant`s to perform substitution. That then lets thunking
rely much more on `SpecificConstant` wrappers instead of deep-copying
the inst tree with modified types.

This approach to thunking should scale better, particularly as things
like form generics make function signatures more complex, because we can
leverage the existing support for constant evaluation and substitution.
Unfortunately, applying this approach to binding patterns will require
more work; see the TODO near the top of `thunk.cpp` for details.

---------

Co-authored-by: Richard Smith <richard@metafoo.co.uk>
v0.0.0-0.nightly.2026.06.14 v0.0.0-0.nightly.2026.06.13
2026-06-13 00:22:00 +00:00
Nicholas Bishop 40d2d8f68c Revert "Fix crash from accessing a Check::Context during lowering (#7335)" (#7353)
This reverts commit afd679129d.

The commit introduced ASAN errors:

https://github.com/carbon-language/carbon-lang/actions/runs/27436787960/job/81100665405
2026-06-12 23:04:50 +00:00
mstr-six 250da35c3b Recover when converting to an invalid integer type (#7342)
Converting an integer value to a destination type that is not a valid
integer type -- such as `i8388609` or `i16777216`, whose bit widths are
diagnosed as invalid -- hit a CHECK failure in
`TypeStore::GetIntTypeInfo` during constant evaluation of `int.convert`
/ `int.convert_checked`:

```
CHECK failure at toolchain/sem_ir/type.cpp:189: int_info: Type type(...) is not an integer type
```

The width error is already diagnosed when forming the type
(`IntWidthNotMultipleOf8` / `IntWidthTooLarge`), so `PerformIntConvert`
and `PerformCheckedIntConvert` now use `TryGetIntTypeInfo` and produce
an error value instead of crashing, following the existing
`SemIR::ErrorInst::ConstantId` convention in `eval.cpp`.

Added a file test covering all three reproducers from the issue
(`i8388609`, `i16777216`, `Core.Int(8388609)`); it crashes without this
change. The full `//toolchain/testing:file_test` suite (1578 tests)
passes.

Fixes #7278.

I have reviewed this change and take responsibility for it.

Assisted-by: Claude
2026-06-12 21:19:57 +00:00
Nicholas Bishop afd679129d Fix crash from accessing a Check::Context during lowering (#7335)
In generate_ast.cpp, an `CarbonExternalASTSource` is installed that has
a `Check::Context` pointer. During lowering, this `ExternalASTSource` is
still installed, and using it can cause a crash if the now-invalid
pointer is dereferenced.

Fix by adding a new `ReadOnlyASTSource` in sem_ir, and using that during
lowering.

`CarbonExternalASTSource` now inherits from `ReadOnlyASTSource` to avoid
some code duplication.

In generate_ast.cpp, we now always install a multiplex source, even if
there's only one child source. Clang internally keeps pointers to the
top-level `ExternalASTSource` installed via `setExternalSource`, and
those pointers aren't updated if `setExternalSource` is called again. By
using `MultiplexExternalSemaSource`, we can keep the top-level
`ExternalASTSource` pointer the same, and only update its children.

Using `MultiplexExternalSemaSource` this way requires a new constructor
and a method to modify its child sources; added a new LLVM patch adding
those.

https://github.com/carbon-language/carbon-lang/issues/7142
2026-06-12 18:05:19 +00:00
mstr-six f3b8e231ca Recover base declarations missing a colon (#7341)
Malformed `base` declarations with an omitted colon need two different
recovery paths. For `extend base`, the consumed `extend` modifier
requires the parse tree to retain its `BaseColon` and base expression
children, so this synthesizes an errored `BaseColon` and continues
parsing the expression.

Other malformed forms, such as `base calss X {}`, now use the standard
declaration-error recovery: emit `ExpectedAfterBase`, skip past the
likely declaration end, and form an errored `BaseDecl` without inventing
a colon or cascading diagnostics.

The regression covers `extend base Foo;`, bare `base;`, and the reviewer
counterexample `base calss X {}`.

Tests:
- `prek run --files toolchain/parse/handle_base.cpp
toolchain/parse/testdata/class/fail_base.carbon`
- `./scripts/run_bazelisk.py test -c dbg //toolchain/parse/...`
- `./scripts/run_bazelisk.py test -c dbg //toolchain/testing:file_test`

AI assistance: OpenAI Codex helped inspect the parser recovery path,
implement the change, and run verification. The operator reviewed and
authorized the contribution.

Assisted-by: OpenAI Codex
v0.0.0-0.nightly.2026.06.12
2026-06-11 22:33:29 +00:00
Christopher Di Bella 103fa5dadf Remove LICENSE from exported files (#7344) 2026-06-11 22:09:42 +00:00
Richard Smith c3fc59b8b9 Don't form a bound method when calling a C++ operator. (#7345)
Because we now support calling a function with a `self` parameter
directly, we can unconditionally call `operator$(lhs, rhs)` rather than
calling `lhs.operator$(rhs)` if the selected operator function happens
to be a member function.

This makes the logic a bit simpler and the SemIR a bit smaller.

We can't do the same for Carbon operators, unfortunately, as we use the
member access to trigger impl lookup.
2026-06-11 21:49:20 +00:00
Christopher Di Bella e83422b375 Declare package licence type (#7343) 2026-06-11 20:28:37 +00:00
Richard Smith 6fe9db297d Fix crash after anonymous generic binding deduction failure (#7330)
A binding can have a constant value that is an `ErrorInst` during error
recovery. In that case, deduction would crash when attempting to
diagnose that the binding had no deduced value.
2026-06-11 19:20:22 +00:00
Chandler CarruthandGeoff Romer f7e628562f Shrink debug info emitted for CARBON_CHECK message formatting (#7339)
This is based on an idea suggested during review of the original type
erasure PR.

The type-erased check failure path lowers each check through
`CheckFailFormat<Ts...>`, which builds one format adapter per value,
down to the out-of-line `CheckFailImpl`, which takes an array of
base-class `format_adapter*` pointers. Previously a separate variadic
`CheckFailWithAdapters<Adapters...>` template sat in between: it existed
only to bind the adapter temporaries to named parameters so that
pointers to their base class could be collected into a `std::array` and
outlive the call to `CheckFailImpl`.

This removes that layer. `CheckFailFormat` now builds the pointer array
directly, in the braced-init-list of the `CheckFailImpl` call, using a
small `CheckFailFormatAdapterAddr<T>` helper to take the base-class
address of each adapter. The adapter temporaries are materialized as
named parameters of that helper within the same full-expression as the
`CheckFailImpl` call, so they remain alive across the call without a
dedicated function for that purpose.

The win is in debug info, not code. `CheckFailWithAdapters<Adapters...>`
was instantiated once per distinct adapter-type sequence in every
translation unit that uses `CARBON_CHECK`, and each instantiation
carried its own DWARF records -- type entries, string-table offsets, and
range lists. Dropping it removes those records from every such
translation unit. The generated machine code is unchanged.

Measured impact (fastbuild, the inputs to the inner-loop links):

- First-party object files shrink by 173,728 bytes (-0.233%) across the
`carbon-busybox` link inputs; 232 of 270 objects get smaller and none
grow. The largest reductions are in the check-densest translation units
(`type_completion`, `type`, `import_ref`, `function_context`,
`constant`, ...).
- Per `bloaty`, the reduction is almost entirely DWARF (`.debug_info`,
`.debug_str`, `.rela.debug_str_offsets`, `.debug_rnglists`); the loaded
code (VM size) is unchanged.

Assisted-by: Claude Code

---------

Co-authored-by: Geoff Romer <gromer@google.com>
2026-06-11 17:53:31 +00:00
Richard Smith 77790e44a6 Refactor and extend tool usage skills (#7338)
Split out the `prek` tool usage instructions into a separate skill. This
should make the agent more likely to realize the skill is relevant to a
particular task and consult it. Extend the skill to include instructions
for using `prek` in a jj workspace, and add a helper script for that
situation.

Add a `jj` skill, with the main purpose being to instruct the agent to
use `jj` not `git`, and to use `--no-pager` when running it.

Extend the `bazel` tool description slightly to more strongly encourage
agents to read and follow it.

Assisted-by: Gemini via Antigravity
2026-06-11 17:18:16 +00:00
Richard Smith 25e72882fc Implement Core.CharLiteral operations from #6710 and #7314 (#7316)
Adds support for arithmetic and comparison operators on
`Core.CharLiteral`s, as well as conversions between `CharLiteral` and
integer types.

Make some minor tweaks to fix skill issues encountered while making this
change.

Assisted-by: Gemini via Antigravity
2026-06-11 16:45:39 +00:00
Christopher Di Bella a914dba888 Add utils/vscode/BUILD (#7337)
This helps with some VSCode derivatives' extension management.
v0.0.0-0.nightly.2026.06.11
2026-06-10 23:04:09 +00:00
Geoff Romer b04634a0cd Implement a custom LLDB formatter for Carbon IDs (#7333)
This removes the inheritance noise, and adds label prefixes for
consistency with the raw textual format.

Before:
```
> p function_info.first_owning_decl_id
(Carbon::SemIR::InstId) {
  Carbon::IdBase<Carbon::SemIR::InstId> = {
    Carbon::AnyIdBase = (index = 0x50000023)
  }
}

> p function_info.call_param_ranges.implicit_end_
(Carbon::SemIR::CallParamIndex) {
  Carbon::IndexBase<Carbon::SemIR::CallParamIndex> = {
    Carbon::IdBase<Carbon::SemIR::CallParamIndex> = {
      Carbon::AnyIdBase = (index = 0x00000001)
    }
  }
}
```

After:
```
> p function_info.first_owning_decl_id
(Carbon::SemIR::InstId) inst50000023

> p function_info.call_param_ranges.implicit_end_
(Carbon::SemIR::CallParamIndex) call_param1
```

The benefit compounds when printing aggregates (which often lack `Dump`
support or omit information from it). For example, this change reduces
`p function_info` from 129 lines to just 31 (including reducing the
`call_param_ranges` field from 32 lines to just 1):

```
> p function_info
(Carbon::SemIR::Function) {
  Carbon::SemIR::EntityWithParamsBase = {
    name_id = name1
    parent_scope_id = name_scope50000002
    generic_id = generic<none>
    first_param_node_id = nodeB
    last_param_node_id = node12
    pattern_block_id = inst_block5000000E
    implicit_param_patterns_id = inst_block5000000A
    param_patterns_id = inst_block0
    is_extern = false
    extern_library_id = library_name<none>
    non_owning_decl_id = inst<none>
    first_owning_decl_id = inst50000023
    definition_id = inst<none>
  }
  Carbon::SemIR::FunctionFields = {
    call_param_patterns_id = inst_block5000000C
    call_params_id = inst_block5000000D
    call_param_ranges = (implicit_end_ = call_param1, explicit_end_ = call_param1, return_end_ = call_param1)
    return_type_inst_id = inst<none>
    return_form_inst_id = inst<none>
    return_pattern_id = inst<none>
    special_function_kind = None
    virtual_modifier = None
    virtual_index = 0xffffffff
    evaluation_mode = None
    self_param_id = inst50000020
    special_function_kind_data = any_raw<none>
    body_block_ids = size=0 {}
  }
}
```
2026-06-10 18:19:07 +00:00
Chandler Carruthandjosh11b 7871237c15 Move self to the explicit () parameter list (proposal #7016) (#7272)
Implements proposal #7016: `self` moves from the deduced implicit list
(`fn F[self: Self]()`) to the front of the explicit list. Its type may
be written explicitly (`fn F(self: Self)`) or omitted, in which case it
defaults to `Self` (`fn F(self)`, `fn F(ref self)`); `self` in the
implicit list is rejected.

Throughout checking, `self` is modeled as the first explicit parameter.
Because a method is just a function whose first parameter is `self`, it
can also be called as an ordinary function with the receiver passed
explicitly (`Type.M(obj, ...)`), not only as `obj.M(...)`. A new
`SemIR::CallArgParamPatterns` helper chooses the parameters matched
against the explicit arguments, excluding a leading `self` only when it
is supplied as a method-call receiver; arity checking, conversion, and
generic deduction use it. The resulting SemIR and lowering are
unchanged: `self` is still `call_param0`, and witnesses, thunks, and
vtables are unaffected.

An omitted `self` type is parsed as a `SelfBindingPattern` node with no
type expression; checking synthesizes the `Self` type so it behaves
exactly like `self: Self`. However, the exact spelling used must match
between a forward declaration and a definition, following #3763's rules
around declaration matching.

Generated functions, thunks, and C++ interop import/export build `self`
as the first explicit parameter, and the `self`-type override (e.g.
Derived->Base for a virtual override) applies to the explicit `self`.
Placement is validated by new diagnostics: `SelfInImplicitParamList`,
`SelfNotFirstParam`, and `SelfOutsideParamList`. The benchmark source
generator and the documentation adopt the `(self)` shorthand; the
prelude, the examples, and the test data are migrated in the following
commits.

Assisted-by: Claude Code with Claude Opus 4.7

---------

Co-authored-by: josh11b <15258583+josh11b@users.noreply.github.com>
2026-06-10 15:30:43 +00:00
Richard Smith fb05da761f Fix formation of invalid value_of_initializer instructions. (#7329)
This is only valid when the operand is an initializing expression that
holds a copy of the value, but we were incorrectly also forming it when
the operand was an in-place initializing expression.

Fixes a crash in lowering when attempting to lower an invalid
`value_of_initializer`.
2026-06-10 15:28:56 +00:00
Chandler Carruth 41e3c9bd82 Type-erase CARBON_CHECK message formatting. (#7325)
`CARBON_CHECK` and `CARBON_FATAL` messages are formatted with
`llvm::formatv`. Previously each check site that had a message
instantiated its own copy of the formatv machinery -- a `formatv_object`
over a tuple of per-argument format adapters, plus that tuple -- in
every translation unit, keyed on the site's file, line, condition, and
format strings. A translation unit with many checks paid for that
machinery over and over.

This restructures check failure so that the formatting machinery is
compiled exactly once, and only a single small adapter is instantiated
per distinct value type per translation unit:

- `CheckFailImpl` (out-of-line) now takes the message's format string
and an array of already-type-erased `format_adapter`s, and renders the
whole failure message -- prefix plus the extra message -- directly into
one stream. The extra message is rendered in place, so no separate
string is ever materialized for it.

- `FormatvInto` (in the `.cpp`) renders a format string over that
adapter array. Rather than instantiate `llvm::formatv`, it drives the
formatv replacement loop over the public
`formatv_object_base::parseFormatString`, so this rendering code exists
exactly once. (A TODO notes that we should add a type-erased entry point
upstream in LLVM rather than reimplement the loop here.)

- The lowering from the macro down to that out-of-line call is split so
that the only per-check-site instantiation is trivial:
- `CheckFail<...>` is instantiated once per site, since its file, line,
condition, and format template-string parameters are unique to the site.
It just lowers those compile-time strings to ordinary arguments and
forwards to `CheckFailFormat`.
- `CheckFailFormat<Ts...>` is instantiated once per distinct value-type
sequence and shared across sites; it builds one type-erased adapter per
value.
- `CheckFailWithAdapters<Adapters...>` collects pointers to those
adapters into an array and calls `CheckFailImpl`. It is a distinct
function so the adapter temporaries stay alive while pointers to their
base class are in flight.

Format semantics, including runtime format-string validation, are
unchanged, and the rendered message is byte-for-byte identical.

For `DCHECK` in optimized builds the check is dead code; its arguments
are now routed through a trivial `IgnoreDeadCheckArgs` no-op rather than
`CheckFail`. This still type-checks the arguments so they cannot bitrot,
without instantiating any formatting machinery for them and without
provoking unused-variable warnings.

Measured full-rebuild impact (353 first-party translation units,
fastbuild): -112.6s CPU, -6.9% relative to trunk.

Assisted-by: Claude
2026-06-10 06:49:00 +00:00
Christopher Di Bella eaf16a5250 Adapters should only be destroyable if their adapted type is destroyable (#7271)
Adapters were erroneously satisfying `Core.Destroy` because we were
directly getting the object's representation without consideration for
abstract and adapted types. This change ensures that adapted types'
representations are used instead of the adapter types.
v0.0.0-0.nightly.2026.06.10
2026-06-10 00:48:33 +00:00
Richard Smith c7b60662f7 CharLiteral difference should be an IntLiteral (#7314)
Change the result type `CharLiteral - CharLiteral` from `i32` to
`Core.IntLiteral`.

Assisted-by: Gemini via Antigravity
2026-06-09 23:26:22 +00:00
Chandler Carruth ad1578166f Freeze the ruff pre-commit and pin ty's version (#7331)
Hopefully this will get us to more consistent behavior between local and
CI runs of these checks.

Assisted-by: Antigravity with Gemini
2026-06-09 22:48:16 +00:00
Geoff Romer d63e929135 Support dumping ImportIRInstIds (#7328) 2026-06-09 22:17:18 +00:00
Geoff RomerandRichard Smith 85c53fa00c Reimplement derived class thunk in terms of down-casting (#7322)
This helps us move away from the clone-with-modifications approach to
thunking, which gets unwieldy as signatures get more complex.

---------

Co-authored-by: Richard Smith <richard@metafoo.co.uk>
2026-06-09 21:10:18 +00:00
Lucile Rose Nihlen 1a26b57732 add first implementation of carbon build subcommand (#7239)
This is the first draft of the implementation of
[p6333](https://docs.carbon-lang.dev/proposals/p6333.html).

The `build` subcommand shared logic with the `compile` and `link`
subcommands,
so I've moved some of the functionality in `compile` and `link` to
shared
`CompileDriver` and `LinkDriver` classes, respectively. This also
required exposing the
`CompileOptions` and `LinkOptions` subcommand structs for re-use.

There's still some work to do on the proposal, most notably the package
include automatic path resolution and import, and the refactors to
`carbon compile`.
2026-06-09 20:24:01 +00:00
Richard Smith e7ffb559f5 Reorganize lower interop tests. (#7327)
Split existing class and function tests into
`{class,function}/{import,export}` as appropriate. Remove the now-empty
`reverse/` directory.
2026-06-09 17:50:52 +00:00
d173121dc6 Name lookup design doc update (#7317)
Assisted-by: Gemini via Antigravity

---------

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
Co-authored-by: Dana Jansens <danakj@orodu.net>
2026-06-09 16:50:18 +00:00
Dana Jansens 233a58fcb1 Fix ty errors for missing generic parameters (#7326)
Mostly these errors were around `dict` missing arguments, and they are
almost always `[str, Any]`.

But a real thorn here was `xml.etree.ElementTree.Element`. `ty` insists
that this is a generic type, and indeed it appears to be one, or
becoming one, in some python version. But it is not generic in python
3.12. So we are stuck in an unsolvable land where:
- `ty` gives an error unless you write `[str]` on the type, because it
thinks it is generic.
- python3.12 gives an error if you do write `[str]` on the type, because
it thinks it is not generic.

Forcing `ty` to target exactly python 3.12 does not help. So I have just
used a linter-ignore comment on that line.
2026-06-09 15:08:39 +00:00
josh11bandJosh L efb78c593c Update design for proposal #6395: Type completeness in extend (#7315)
Assisted-by: Gemini via Antigravity

Co-authored-by: Josh L <josh11b@users.noreply.github.com>
v0.0.0-0.nightly.2026.06.09
2026-06-08 21:27:48 +00:00
Lucile Rose Nihlen 014c7346d6 Canonicalize the path to clang resource directory (#7321)
When building Carbon on Fedora, clang reports the
resource directory as `/usr/bin/../lib/clang/22`.
This fails to string match against `/usr/lib/clang/22`
and so bazel reports an error.

This PR canonicalizes the path returned by clang
so that it will string match successfully.
2026-06-08 18:56:07 +00:00
Chandler Carruth 3625e74a7d Out-of-line cold YAML and debug-printing paths from widely-included headers (#7320)
These were defined inline in headers reached by most of the toolchain,
and as non-template functions their bodies -- including some very
expensive template instantiations -- are compiled in every including TU
even though they are only cold debug/dump paths:

- BundleStore's YAML output entry points instantiate IdAndKind::Dispatch
  over all ~50 ID kinds (two ~365ms instantiations per TU) plus
  Yaml::OutputScalar/std::function machinery; moved to a new bundle.cpp.
- TypeStore, ConstantValueStore, NameStoreWrapper, and SharedValueStores
  OutputYaml bodies wrap capturing lambdas in std::function via
  Yaml::OutputMapping; moved to their existing .cpp files.

This change appears to be worth another 10% compile time reduction.

Assisted-by: Claude
v0.0.0-0.nightly.2026.06.08
2026-06-08 02:42:23 +00:00
Chandler Carruth 7901fb3857 Don't include expensive Clang headers in widely-included headers (#7319)
Fundamentally, this uses forward declarations of Clang types to reduce
the overall compile time cost of Clang headers across the codebase.

Tracing and profiling showed ~2s of every check TU's ~8-12s compile time
going just to parsing Clang frontend and AST headers pulled in via a few
sem_ir and check headers that only use the Clang types by pointer or
reference:

- sem_ir/cpp_file.h (reached via sem_ir/file.h by ~150 TUs) included
clang/Frontend/CompilerInstance.h, clang/CodeGen/ModuleBuilder.h,
clang/AST/Mangle.h, and llvm/IR/Module.h. CppFile's accessors move out
of line to a new cpp_file.cpp and the header now forward-declares the
Clang types.
- check/cpp/context.h (reached via check/context.h by ~100 TUs) included
clang/Frontend/FrontendAction.h and clang/Parse/Parser.h, pulling in
clang's Sema.h and ASTUnit.h.
- sem_ir/clang_decl.h included clang/AST/Decl.h; the three small
functions that need complete Clang types move out of line.
- sem_ir/cpp_overload_set.h included clang/Sema/Overload.h solely for
the three-field OverloadCandidateSet::OperatorRewriteInfo, which is now
mirrored as CppOverloadSet::OperatorRewriteInfo, and clang/AST/Decl.h
solely for a pointer.
- sem_ir/name_scope.h's clang/AST/DeclBase.h include was vestigial.

TUs (and more narrowly included headers) that genuinely use the Clang
definitions now include the Clang headers directly.

Representative compile times (fastbuild, aarch64), combined with the
preceding instantiation-cost changes, relative to trunk:
- check/eval.cpp: 11.85s -> 6.94s (-41%)
- check/handle_operator.cpp: 7.71s -> 3.30s (-57%)
- language_server.cpp: 6.68s -> 3.16s (-53%)
- lower/handle.cpp: 6.75s -> 3.66s (-46%)
- sem_ir/file.cpp: 8.60s -> 6.11s (-29%)
- driver.cpp: 6.68s -> 4.78s (-28%)

Measured full-rebuild impact (316 first-party TUs, fastbuild): -689.5s
CPU, -29.9% relative to trunk.

Assisted-by: Claude
2026-06-07 16:27:22 +00:00
Richard Smith 20972ec748 Don't perform access-control checks on namespace-scope entities. (#7310)
Instead of silently producing an `ErrorInst::InstId` when looking up a
private qualified name in the current package, bypass the access check.
We don't need it -- private names from other libraries are filtered out
by the import logic.

Also fix `DiagnoseInvalidQualifiedNameAccess` to actually always produce
a diagnostic, instead of silently ignoring access control failures in
non-class types. This is a no-op after the fix to the access logic,
since we only allow access control at class and namespace scope
currently, but should avoid this issue from recurring when that changes.

Assisted-by: Gemini via Antigravity
v0.0.0-0.nightly.2026.06.06 v0.0.0-0.nightly.2026.06.07
2026-06-05 23:30:09 +00:00
Richard Smith ae6846197a Remove trailing () from Core.*Literal and Core.Bool. (#7313)
We exposed `Core.IntLiteral()`, `Core.FloatLiteral()`,
`Core.CharLiteral()`, and `Core.Bool()` as functions as a workaround,
because we had no way to provide the type names without parentheses that
the design requests. But now we can do so, by using an alias. Switch all
of these over from being functions to simply being names of the
corresponding types.

Assisted-by: Gemini via Antigravity
2026-06-05 22:33:30 +00:00