Commit Graph
3392 Commits
Author SHA1 Message Date
Dana Jansens eca38a90e1 Remove empty lambda parameter lists (#7760)
clang-tidy 24 warns about these being redundant
2026-09-10 20:10:36 +00:00
ATHARVA d98784b972 Fix crash when initializing class with omitted base class (#7740)
### Description
When looking up default initializers for class elements in
`ConvertStructToClass`, the compiler previously assumed that every
member looked up from the class scope was a `FieldDecl` and called
`GetAs<SemIR::FieldDecl>` directly.

For a derived class with a base class, looking up `base` returns a
`BaseDecl`, which caused a `CHECK` assertion failure when casting to
`FieldDecl`. Use `TryGetAs<SemIR::FieldDecl>` instead so non-`FieldDecl`
entries like `BaseDecl` are recognized as having no default initializer,
cleanly diagnosing that the `base` field is missing.

Fixes #7722

Assisted-by: Google Deepmind Antigravity
2026-09-10 19:29:24 +00:00
Dana Jansens 6f1ae86ce4 Disable -Wunused-template in clangd-tidy (#7750)
This is firing on some of our _used_ templates in eval.cpp in clang-tidy
24

It was coming to `-Wall` for clang as well
(https://github.com/llvm/llvm-project/issues/202945) but was reverted
due to issues like false positives
(https://github.com/llvm/llvm-project/pull/218638). Some fixes were
applied to try enable in `-Wall` in clang 23
(https://github.com/llvm/llvm-project/pull/222336) but it still remains
disabled by default for clang.
2026-09-10 19:28:25 +00:00
Dana Jansens dbcae83784 Passthrough the StringRef to mapRequired instead of just the data() pointer (#7756)
The StringRef represents a bounded region of a string, but using data()
drops the end bound, and makes LLVM construct a new StringRef starting
in the same position and going until a nul terminator. If this worked
correctly before, it was because the StringRef was always pointing to a
full `std::string` or the tail of one.
2026-09-10 19:19:56 +00:00
Dana Jansens c6c40cc444 Avoid using string operator += for a single character (#7747)
This is flagged as a mistake by clang-tidy 24. String's operator `+=` is
pretty bad in general, this moves a few uses to push_back.
2026-09-10 16:39:08 +00:00
Nicholas Bishop c24adea6fe Allow assignment to be called on a template-dependent lhs (#7741) 2026-09-10 15:07:31 +00:00
Dana Jansens 2aeecef17a Gracefully handle member access on a runtime type value (#7744)
Avoid CHECK failure when performing member access on a runtime type
value. We will just fail to find the CanonicalFacetOrTypeValue and then
fail lookup.
2026-09-09 23:05:48 +00:00
Christopher Di Bella 431e349757 Allow witness tables to support aliases and other types of StructValue (#7738)
Changing the check from "is `FunctionDecl`" to "has `FunctionType`"
provides us with more flexibilty to use aliases and other types of
`StructValue`.
2026-09-09 19:35:43 +00:00
Richard Smith e090a0ef65 autoupdate: add missing verbose check. (#7742)
A check for `args.verbose` was missing for one line of autoupdate's
verbose output. Add a wrapper function to print verbose output to fix
this and to make it easier to get verbose output right in future.
2026-09-09 19:34:28 +00:00
Richard Smith 49c6f488b6 Include spliced inst value in fingerprint while lowering. (#7739)
This prevents different template instantiations from getting
over-eagerly merged. Unfortunately we don't have a good middle-ground
yet, and this effectively disables all merging for templates. We may be
able to find some smart way to fingerprint spliced instructions so that
we can still merge template instantiations, but for now this change is
just fixing the wrong-code bug.
2026-09-09 17:54:10 +00:00
Richard Smith a9fee27bbb Add test for symbolic arguments to templates. (#7736)
Test passing a template argument or a symbolic argument to a template.
Fix a bug in the template case where we'd crash when instantiating a
dependent discarded expression, because conversion produced an
`InstId::None` which the actions machinery did not expect and crashed
on.
2026-09-09 01:39:54 +00:00
Richard Smith d92a981083 Add explicit testing for use of non-constant template arguments. (#7735)
Also move another template test into the template/ subdirectory.
2026-09-08 23:36:36 +00:00
Özgür T. Önsoy c6d8d29172 Diagnose redundant redeclarations in impl files (#7695)
While forward declarations in impl files are allowed, having one in the
impl file is redundant when we also have one in the API file.
2026-09-08 23:15:42 +00:00
Lucile Rose Nihlen ca9e985fa8 Reconcile function default values between decl and def (#7665)
Updates the pattern matching code to support unspecified default values.
Adds logic to decl and def merge code to diagnose mismatches in defaults
if specified in both places, or if let entirely unspecified.

Per https://github.com/carbon-language/carbon-lang/pull/7521.
2026-09-08 20:41:58 +00:00
Richard Smith 5a07a14fe9 Support for lowering templates (#7727)
Add basic support for lowering templates: we can now lower `SpliceInst`
in the case where the generic and specific are from the same file (and
we don't support importing templates from other files yet in general).
In order for this to work, lowering needs to be able to query the
expression category, and to handle instructions that appear to be
(template) constants in the generic but turn out to be non-constant in
the specific, so support for that is added.

Switch `type_of_inst` from being added as an action inst to being added
as a normal inst, since it's not an action and the old approach led to a
crash in lowering.
2026-09-08 18:39:57 +00:00
David Blaikie 3339dd85de Lower FacetType to TypeType to match FacetValue lowering (#7734)
SemIR::FacetValue lowers to context.GetTypeAsValue(), which produces a
constant of LLVM type %type (context.GetTypeType()). However,
SemIR::FacetType previously fell back to an anonymous empty struct {},
causing an argument type mismatch assertion failure when passing a
FacetValue to a function expecting a FacetType parameter.

Identified by @danakj in #7731

Assisted-by: Antigravity with Gemini
2026-09-08 18:32:34 +00:00
ATHARVA e5f30d1738 Cache SemIR::Mangler in FileContext (#7730)
### Description
When lowering symbols (functions, global variables, and vtables), a new
`SemIR::Mangler` was being created on each call. Each `Mangler` creates
its own `InstFingerprinter` with a fresh store, preventing any
fingerprint computations from being reused across manglings.

This PR caches a single `SemIR::Mangler` instance in `FileContext` so
that the underlying fingerprint cache is preserved and reused across all
symbol manglings within the file.

Assisted-by: Google Deepmind Antigravity
2026-09-08 17:53:10 +00:00
DavidLoftusandDavid Blaikie 301172f589 Update Carbon::Format to produce semi-reasonable output. (#7687)
Makes following changes to Carbon::Format()

- TokenKind::Period (i.e. `.`) should never have a space before or after
it.
- TokenKind::CloseSquareParen (i.e. `]`) should be treated as packed
content (no space preceeding it)
  - Only exception I can think of is `impl forall [...]`
- Remove preceeding space from `[` and `(` if previous token was an
identifier (or identifier-ish token)
- Remove seperator following `++` / `--` unary operators.
- Explicit gaps in source code should be retained, up to 2 new lines.

Multiple test files were added to test formatting. 

I imagine eventually this will need to be updated to read parse tree to
gather more context but this atleast lets us get a decent-ish format for
many of our current sample files (e.g. sieve.carbon)

Assisted-With: Gemini / Antigravity

---------

Co-authored-by: David Blaikie <dblaikie@gmail.com>
2026-09-08 16:20:47 +00:00
Richard Smith 812cc1e032 Add SpecificInst to represent a specific version of a template-dependent instruction (#7726)
Replace `refine_type_action` with `refine_inst_action`, and generate a
`specific_inst` instead of an `as_compatible` to represent the specific
version of an instruction that's used as an input to a template action.
This gives us a place to handle other properties of the instruction that
might vary from generic to specific beyond its type, such as its
constant value and its expression category.

For now, we provide a non-template-dependent constant value to the
`specific_inst` in addition to the non-template-dependent type we have
traditionally provided. This doesn't seem to matter for any current
actions, but sets us up to better handle future actions. The
`specific_inst` representation also allows downstream consumers of the
instruction to track which specific they should be requesting
information from. Providing a correct expression category for
`specific_inst` will be handled in a future PR.
2026-09-08 16:01:09 +00:00
Dana Jansens efb7ca9b90 Include ASTContext where it's used in mangler.cpp (#7723) 2026-09-04 16:52:16 +00:00
Lucile Rose Nihlen 2952ec9c10 Fix a crash when checking a nested tuple-pattern (#7716)
Adds a virtual node to `DefaultValuePattern` to end the
`ExprRegionForPattern` before checking the expression
for the default value.

When checking the default value expression, the context
was still configured to interpret expressions as patterns,
which caused some corruption of state with tuple-pattern
subpatterns.

Corrects an assertion failure I found while working on
feedback from #7665.
2026-09-04 01:22:16 +00:00
Dana Jansens 1b969c292b Remove a comment that looks to be left behind from a refactoring (#7718)
The GetFacetTypeForQuerySpecificInterface function has two comments on
top of it. The second one actually refers to what the function does.
2026-09-03 19:56:34 +00:00
Özgür T. Önsoy 5474347d7d Support lexing and parsing positional params (#7651)
This implements lexing and parsing positional parameters such as `$0`.
2026-09-03 19:06:20 +00:00
Nicholas Bishop 27849b385c Add TemplateInst and drop CallCppTemplateAction (#7689)
`TemplateInst` wraps another inst. If that inst is symbolic, it is
treated as a template by `OperandDependence`.

Use this to replace `CallCppTemplateAction` with the more general
`CallAction`.
2026-09-03 17:45:47 +00:00
Richard Smith 7c966c2d59 Initialize specifics in-place. (#7717)
Don't wait until we reach the end of the eval block to set the value
block on the specific. This is a prerequisite for allowing template
actions to read from the specific.
2026-09-03 17:06:22 +00:00
Richard Smith b8814f6c80 Add named constraints for Eq and Ordered. (#7714)
Also add a default for `EqWith.NotEqual`.

Switch advent examples to use these named constraints, and also go
through all the other TODOs in the advent examples and fix the ones that
are trivially fixable now.
2026-09-03 16:20:13 +00:00
Dana Jansens 2299b94b20 Use match_first to make the same_self_and_interface.carbon test pass again (#7711) 2026-09-03 14:58:13 +00:00
Dana Jansens b6ba4ecdbb Use match_first to make the impl_recurse_with_simpler_type_in_generic_param_bidirectional_no_cycle.carbon test pass again (#7712) 2026-09-02 21:56:12 +00:00
Richard Smith 01815b6c47 Fix refinement of call action operands. (#7710)
Two somewhat related fixes. The first is call-specific for now (because
it's the first action to take a `MetaInstId`), and the second is general
across all actions, but it seems like calls are the easiest place to hit
it.

1) Add support for refining inst blocks as action operands. Refine all
   the insts in the block, using the appropriate InstId-derived type.
2) When an action operand is a `MetaInstId` referring to an unattached
   constant, form a corresponding attached constant. This comes up when
   forming (for example) an implicit `AddWith(%T)` call, where the `%T`
   operand is an unattached constant.

This causes us to form correct specifics in more cases, where previously
we formed specifics that contained values that were still
template-dependent.

This unfortunately causes some existing template tests to produce more
errors, but those errors reflect cases where we were previously silently
doing the wrong thing.
2026-09-02 20:36:18 +00:00
Nicholas Bishop d8bb181db8 Fix SemIR not showing insts used to compute FieldDecl type (#7706)
Add an `ExprRegionId` to `FieldDecl`. This required moving the `NameId`
into `Field`.
2026-09-02 20:28:05 +00:00
Dana Jansens ed074e85ab Include StringSet where it is used (#7708) 2026-09-02 19:38:23 +00:00
Dana Jansens b8eca6a6da Include the ASTContext header where it's used (#7701) 2026-09-02 17:35:31 +00:00
Richard Smith 2209a3477e Step through splices when checking for a bound method. (#7700)
`GetCallee` is sometimes called on a spliced instruction, and is
checking its exact inst operand to see if it's a `BoundMethod`. This
fails if the `BoundMethod` is wrapped in another instruction, such as a
splice. Normally our approach for such a situation would be to
constant-evaluate the operand, but that doesn't work here because the
`BoundMethod` will be non-constant if its bound `self` is. So instead we
now step through splice instructions manually when looking for the
`BoundMethod`.
2026-09-02 15:19:59 +00:00
Richard Smith 6724d506f3 Add cycle detection to instruction fingerprinting. (#7691)
Use a version of Brent's algorithm, suitably adapted to work for our
worklist-based graph traversal, to very cheaply detect if instruction
fingerprinting fell into a cycle and terminate cleanly with a dump of
the cycle.

The algorithm does not immediately catch when we enter a cycle, but is
guaranteed to catch it eventually (generally after running through the
cycle no more than twice).
2026-09-02 00:33:32 +00:00
Lucile Rose Nihlen 3e64670122 Transform pattern default values to SemIR (#7649)
Adds check functionality to transform the parse node to SemIR. Only
supported for single declarations of functions, re-declaration and
imports to come in a subsequent PR.

Per #7521.
2026-09-01 16:12:34 +00:00
Lucile Rose Nihlen 91c1e1049d Add parsing of default value exprs in pattern lists (#7631)
Adds parsing support only for default value expressions in pattern
lists, including leaving the default value unspecified with an
underscore `_`.

Per #7521.
2026-09-01 01:19:13 +00:00
Richard Smith 742684635a Add --verbose / -v flag to autoupdate. (#7692)
With this set, autoupdate will print messages indicating what it's
doing, such as the command that it's invoking to execute bazel. For
example:

```console
$ ./toolchain/autoupdate_testdata.py -v toolchain/check/testdata/basics/empty.carbon 
Detected --compilation_mode: fastbuild
/home/zygoloid/carbon-lang/scripts/run_bazel.py run -c fastbuild --experimental_convenience_symlinks=ignore --ui_event_filters=-info,-stdout,-stderr,-finish //toolchain/testing:file_test -- --autoupdate --print_slowest_tests 0 --file_tests=toolchain/check/testdata/basics/empty.carbon
[... normal output ...]
```
2026-08-31 20:59:40 +00:00
DavidLoftus dc2ee5bd5e Implement lsp/formatting for Carbon::LanguageServer (#7688)
Implements formatting support within LSP. Current implementation
performs while file formatting, we just replace file with output of
Carbon::Format()

https://github.com/carbon-language/carbon-lang/pull/7687 independently
improves formatting so that this output is somewhat decent.

Assisted-With: Gemini / Antigravity
2026-08-31 16:38:38 +00:00
Nicholas Bishop f519cccaf2 Add CallAction to allow deferring calls (#7682)
Calls with template callee or args can now be deferred via an
InstAction. This allows code like this to check:

```carbon
import Cpp inline '''
template<typename T>
struct C {};
''';

fn F(generic T: type) {
  let unused c: Cpp.C(T) = Cpp.C(T).C();
}
```
2026-08-28 18:00:58 +00:00
Richard Smith 0ea8fb2e74 Add documentation for our constrained overload set idiom. (#7681)
As used in #7679.
2026-08-27 18:51:30 +00:00
Chandler Carruth ba0011bca8 Enable rumdl markdown line-length enforcement and reflowing (#7667)
This should handle over-long lines. I had tried to make the normalize
method work, but it doesn't seem promising and so let's at least enable
this version.

Assisted-by: Antigravity with Gemini
2026-08-27 00:13:39 +00:00
Richard Smith 197cae22f1 Use consistent pattern to generate constrained overload sets. (#7679)
Follow the pattern used by eval_inst.h's `EvalConstantInst` to generate
declarations of an overload set that handles some but not all typed inst
classes. The pattern is:

* A template computes the signature to use for a particular overload,
producing a fallback `() -> void` signature for overloads that should
not exist.
* The `.def` file is used to generate a declaration per instruction
kind, whose signature is generated by the template.
* The `() -> void` signature that all the "should not exist" cases
generate is explicitly deleted.

This avoids the redundancy of manually declaring all the overloads, as
we did for `PerformAction`, and is less error-prone as it both catches
signature errors and definitions of overloads that are dead code and
should not exist, as it did for the `FacetAccessType` overload of
`LowerInst`.
2026-08-26 19:34:37 +00:00
Chandler Carruth 95fc6fae22 common: Decouple LLVM hashing dependencies from common/hashing.h (#7646)
- Move formatted printing to `hashing.cpp` instead of `hashing.h`
- Separate APInt and APFloat hashing specializations into a new
`hashing_llvm.h`
- Update toolchain/base dependencies and include sites that hash LLVM
data types to include `hashing_llvm.h`

Combined, this reduces the transitive includes caused by `hashing.h`.

Assisted-by: Antigravity with Gemini
2026-08-26 00:41:51 +00:00
Richard SmithandGeoff Romer c7dcc50768 language-server: Remove an unnecessary vector copy on each source change. (#7669)
We track a "next" index into each bucket when we insert instructions.
The insert loop effectively shifts each element in the "next" vector
left by one place, so if we instead start the bucket counts shifted one
place to the right, we can use the same vector for "next" and for the
bucket start indexes.

Assisted-by: Claude Code

---------

Co-authored-by: Geoff Romer <gromer@google.com>
2026-08-25 21:26:46 +00:00
Özgür T. Önsoy 2bdcb1fa62 Unify MergeRedecl functions (#7632)
As discussed in #7620.
2026-08-25 18:43:52 +00:00
Geoff Romer 1410795bf7 Support arbitrary parameter forms in MakeGeneratedFunctionDecl (#7654)
This allows generated functions to have different forms for different
parameters, and by-ref or by-value return forms. As a byproduct, this
allows generated functions to supply a return type _inst_ ID when they
have one, which preserves things like location information.
2026-08-24 21:15:50 +00:00
Nicholas Bishop 0745bda899 Support using Carbon generic types as C++ template parameters (#7673)
Example:
```carbon
import Cpp library "<vector>";

class C(T: type) {
  var v: Cpp.std.vector(T);
}

inline Cpp '''
void F() {
  Carbon::C<int> c;
  c.v.push_back(123);
  std::cout << c.v.back() << std::endl;
}
''';
```

A new `CallCppTemplateAction` is used to delay performing the C++
template call until non-symbolic arguments are known.
2026-08-24 18:53:24 +00:00
Richard Smith 6515090557 Don't provide the "start of file" token to the bracket fixer. (#7675)
We previously passed in the start of file token, classified as
BracketTokenKind::Other, which allowed the bracket fixer to consider
corrections where it inserted tokens (such as a `{`) *before* the
start-of-file token.

Fixes #7672.
2026-08-24 18:14:10 +00:00
Nicholas Bishop 7f3584a123 Support constant InstActions (#7671)
Treat `InstConstantKind::InstAction` the same as
`InstConstantKind::ConstInstAction`. Drop `ConstInstAction`, since the
two now behave the same.

Fix eval for specifics in a couple places to handle `InstId::None`.
2026-08-24 18:05:15 +00:00
Chandler Carruth 369b8fd06f Fix top-of-tree Clang build warnings (#7670)
`-Wunused-template` was added to `-Wunused`, so clean up the things it
found. One of them was a bug in the Clang warning that I've worked
around and reported upstream:

https://github.com/llvm/llvm-project/issues/218429
2026-08-24 15:54:21 +00:00