Mostly wanted to more clearly separate the closing observations from the
rest of the report. Noticed the missing link while I was there so fixing
that too.
This is intended to be used only when creating source locations that are known to be ignored because they are fed into operations whose diagnostics are discarded and that do not store the location in any created object.
As requested in review of #2321.
Per recent discussion, in `... where .A = B`, require that `B` is implicitly convertible to the type of `A` immediately, rather than treating that as part of the criteria that a type must satisfy to satisfy the resulting constraint. Extend the implementation of implicit conversion so that conversion of a type to a constraint checks that the type satisfies the constraint.
As part of implementing this, stop duplicating rewrite constraints as equality constraints. Instead, when checking that a constraint is satisfied, check both its equality constraints and its rewrite constraints. This fixes an infinite recursion that would otherwise be caused by this change, and is also a necessary prerequisite for applying rewrite constraints to equality constraints, where we would otherwise collapse the implied equality constraints to a tautological `V == V` constraint.
In passing, make ErrorBuilder support building the error message more incrementally and use that to improve diagnostics for mismatched values with equality constraints.
This rewrites semantics towards a more pure instruction model, in pursuit of the simple instruction-style output.
I think I can get this approach to type-check as it goes along, but obviously this change doesn't prove that yet. I'm separating it out because it's a large rewrite of the semantics structure, tossing out a lot of what was there before. But I think it does help towards several requests, like setting up a clear path for consolidating duplicate identifiers and making the node style more standardized.
I expect to need to pass multiple args to function calls, that'd probably be storing vectors of args similar to how I'm showing identifiers and integer literals stored.
This removes the semantics namespace because (a) it was getting annoying writing the `::` everywhere, and (b) I think the leaning with Carbon is to avoid namespaces (@chandlerc asked not to put SemanticsIR/SemanticsFactory in a namespace, which is the crux of the issue). But, it's still necessary to avoid name conflicts so I just prefix everything with "Semantics" (still a lot of typing, but no `::`).
Note, not trying to address every last error, just some obvious/easy ones.
```
/usr/local/google/home/jperkins/dev/carbon-lang/common/string_helpers.cpp:200:13: warning: prefer transparent functors 'less_equal<>' [modernize-use-transparent-functors]
auto le = std::less_equal<const char*>();
^
/usr/local/google/home/jperkins/dev/carbon-lang/toolchain/semantics/nodes/function.h:22:45: warning: pass by value and use std::move [modernize-pass-by-value]
Function(ParseTree::Node node, NodeId id, llvm::SmallVector<NodeRef> body)
^
/usr/local/google/home/jperkins/dev/carbon-lang/explorer/ast/declaration.cpp:230:14: warning: static member accessed through instance [readability-static-accessed-through-instance]
return cast<SelfDeclaration>(declaration).name();
^
/usr/local/google/home/jperkins/dev/carbon-lang/explorer/interpreter/type_checker.cpp:1104:33: warning: std::move of the variable 'impl' of the trivially-copyable type 'ConstraintType::ImplConstraint' has no effect [performance-move-const-arg]
impl_constraints_.push_back(std::move(impl));
^
/usr/local/google/home/jperkins/dev/carbon-lang/explorer/interpreter/type_checker.cpp:1145:36: warning: std::move of the variable 'rewrite' of the trivially-copyable type 'ConstraintType::RewriteConstraint' has no effect [performance-move-const-arg]
rewrite_constraints_.push_back(std::move(rewrite));
^
/usr/local/google/home/jperkins/dev/carbon-lang/explorer/interpreter/type_checker.cpp:1156:32: warning: std::move of the variable 'context' of the trivially-copyable type 'ConstraintType::LookupContext' has no effect [performance-move-const-arg]
lookup_contexts_.push_back(std::move(context));
^
/usr/local/google/home/jperkins/dev/carbon-lang/explorer/fuzzing/fuzzverter.cpp:74:42: warning: argument name 'trace' in comment does not match parameter name 'parser_debug' [bugprone-argument-comment]
/*trace=*/false);
^
./explorer/syntax/parse.h:19:17: note: 'parser_debug' declared here
bool parser_debug) -> ErrorOr<Carbon::AST>;
^
/usr/local/google/home/jperkins/dev/carbon-lang/explorer/fuzzing/proto_to_carbon_test.cpp:34:55: warning: argument name 'trace' in comment does not match parameter name 'parser_debug' [bugprone-argument-comment]
const ErrorOr<AST> ast = Carbon::Parse(&arena, f, /*trace=*/false);
^
./explorer/syntax/parse.h:19:17: note: 'parser_debug' declared here
bool parser_debug) -> ErrorOr<Carbon::AST>;
^
/usr/local/google/home/jperkins/dev/carbon-lang/explorer/fuzzing/proto_to_carbon_test.cpp:42:41: warning: argument name 'trace' in comment does not match parameter name 'parser_debug' [bugprone-argument-comment]
&arena, f, source_from_proto, /*trace=*/false);
^
./explorer/syntax/parse.h:25:59: note: 'parser_debug' declared here
std::string_view file_contents, bool parser_debug)
^
/usr/local/google/home/jperkins/dev/carbon-lang/explorer/syntax/parse_test.cpp:27:60: warning: argument name 'trace' in comment does not match parameter name 'parser_debug' [bugprone-argument-comment]
ParseFromString(&arena, "file.carbon", FileContents, /*trace=*/false);
^
./explorer/syntax/parse.h:25:59: note: 'parser_debug' declared here
std::string_view file_contents, bool parser_debug)
^
/usr/local/google/home/jperkins/dev/carbon-lang/migrate_cpp/cpp_refactoring/var_decl.cpp:57:58: warning: string concatenation results in allocation of unnecessary temporary strings; consider using 'operator+=' or 'string::append()' instead [performance-inefficient-string-concatenation]
segments.push_back({type_loc_class, qual_str + " " + range_str});
^
/usr/local/google/home/jperkins/dev/carbon-lang/explorer/fuzzing/ast_to_proto_test.cpp:105:55: warning: argument name 'trace' in comment does not match parameter name 'parser_debug' [bugprone-argument-comment]
const ErrorOr<AST> ast = Carbon::Parse(&arena, f, /*trace=*/false);
^
./explorer/syntax/parse.h:19:17: note: 'parser_debug' declared here
bool parser_debug) -> ErrorOr<Carbon::AST>;
^
```
In summary - some of the changes here are focused on producing the same test results for SemanticsIR, but I think the next step will be to change the SemanticsIR structure to reduce how much is added to the traversal stack.
Switching semantics to a postorder traversal is intended to be more efficient. The traversal stack is to eliminate risk of recursion limits within the semantic analysis that could come from layered code structures. However, we need to start considering the implications for type-checking and what the ParseTree looks like, as well as copying of data here.
As we start thinking about type-checking in SemanticsIR, it's helpful for a function to know its own signature in order to perform lookup recursive calls. The challenge in the post-order walk without this change is it doesn't know it's in a function definition (or similar) until it reaches the FunctionDeclaration; this restructures so that either:
1. For a declaration, the signature is a child of FunctionDeclaration(";")
2. For a definition, the signature is a child of FunctionDefinitionStart("{") which pairs with FunctionDefinition("}"), replacing CodeBlock.
This similarly reorients CodeBlock to be CodeBlockStart("{") as the first child of CodeBlock("}"). I'm not doing that with ParameterList here just because it affects a bit more, and felt like it could be delayed.
Overall, my goal is making the postorder traversal more intuitive along scope boundaries. I think we may also not need subtree_size, so I'm avoiding use of that now.
Currently the SemanticsIRFactory implementation is less clean than I might like (there are a couple comments to this point), but I was starting to feel like a more complete rewrite would be appropriate rather than trying to clean it up further: in particular, I think the node structures are off, but changing them is significant and also changes test output; in turn it may also warrant more substantial ParseTree changes. If you prefer from a reviewer POV, I can do a more complete rewrite.
This does some more work to the run_clang_tidy.py wrapper script, and runs an example pass.
"again" because it's really the proto fuzzer changes that broke it, it had been working before.
"mostly" because there's still an issue within the proto fuzzer that it can't find "port/protobuf.h", i.e. https://github.com/google/libprotobuf-mutator/tree/master/port, but I'm still hesitant to add an include path there.
We don't seem to have any need for `TypeOf*Type` types, and having them introduces the temptation to use them during type-checking, which would lead to types having different behavior when their type-of-type is `Type` versus when it's a more precise type. Remove these types for now.
If we later decide that we want each type literal to have a unique type, as we do for value literals, we can introduce a single value kind for that rather than one for each kind of type.
No changes to `TypeOfMemberName`, `TypeOfParameterizedEntityName`, and `TypeOfMixinPseudoType`, which are placeholders, not real types.
Provides a documented cadence, publishing target, and template for Code of Conduct and moderation transparency reports.
Based on the initial proposal draft from @CelineausBerlin.
Co-authored-by: Céline Dedaj <CelineausBerlin@users.noreply.github.com>
In particular, if we find the name of an interface after `is`, it should
be exapnded to a constraint, including any implied constraints such as
extended interfaces, rather than forming a constraint requiring only
that interface in isolation.
Add checking that a type only satisfies a constraint if it satisfies all of that constraint's equality and rewrite constraints.
Enforce the rule that `=` must be used in impls when specifying associated constant values rather than `==`.
Turn off the pre-#2173 single-step equality behavior. This is getting somewhat ahead of the approved design, but it's a one-line change to restore the old behavior.
Fix `CARBON_CHECK` to handle top-level `,`s in its argument, such as may happen in template argument lists, as this change introduces such a check.
llvm::InitLLVM starts getting stacks on assertion errors. Tieing errs to outs causes outs to be flushed when errs is used (avoiding munging out incompletely flushed output).
LLVM_SYMBOLIZER_PATH is required if `llvm-symbolizer` isn't in the developer's PATH. This sets it via bazel instead of having a developer handle it. I noticed this because the apt install of clang doesn't put llvm-symbolizer in the PATH.
I'd like to make this the default without putting it everywhere, but I don't see a way to do this intrinsically through [the toolchain](https://bazel.build/docs/cc-toolchain-config-reference), and the [rules_cc/defs.bzl](https://github.com/bazelbuild/rules_cc/blob/main/cc/defs.bzl) remains a thin wrapper around the native cc_binary.
Since I'm adding another env, it seems undesirable to have the macos asan workaround separate. As a consequence, this merges it in. Note bazel doesn't support merging a dict and a select, so it's also necessary to have the two env vars at least mildly aware there's something up (and this could get worse if we end up having more selects).
This had already hit one bug in LLVM, and now I've hit another:
https://github.com/llvm/llvm-project/issues/58385
Since this isn't specific to a config, and it seems to be a clear sign
that this isn't the best tested path, let's just drop to the more fully
tested flags. Probably should have done this rather than the more
targeted workaround last time...
This switch is being done in order to make it easier to update tests when the parse tree structure changes. I've been spending a lot of time doing such updates as part of refactoring the parse tree, and I expect more, so that's really at the root of all the refactoring I've been doing to lit updates.
There are lots of ways a declaration can be used before we have the information necessary to handle that use. Issue diagnostics for these.
Interleave declaration and type-checking of global declarations so that declaring a later declaration can depend on the results of type-checking an earlier one.
Incorporates tests added in #2266.
Fixes#1394, fixes#1395, fixes#1396.
Co-authored-by: pmqtt <51272730+pmqtt@users.noreply.github.com>
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
Adds a simple script to merge stdout/stderr and put on labels. This is hidden to the RUN line using lit.cfg.py.
This is my solution to addressing how errors printed by the toolchain break sorting of stdout output; just put stdout first. We could also have toggles for interleaving output or such, which might help test whether we do it properly.
This also moves some previous-distributed replacement logic into lit_autoupdate_base.py: I think having that adjacent to lit.cfg.py is probably the better choice, and it reduces duplication in toolchain scripts. It happens here because I need to change the resulting commands to include the merge.
This change left a test broken and removed a fair amount of test coverage for unrelated features, and after further discussion it's not clear that this is the direction we want to go in.
This reverts commit 6cf2272bbe.
I've refactored the script in order to make it work in more contexts, which is why the delta is lost. I've actually refactored a significant amount with the intent of making the logic easier to understand, because I was also adjusting bits of it.
Some key notes:
- Removes the multi-pass update that was dealing with unfixed line numbers in explorer (I think the current script should work in one pass)
- Fixed explorer to handle multiple line numbers on the same line (turns out we can rely on local format for line numbers).
- Using execv instead of imports because making Python imports work in a setup like this feels like it's not worth it; only a nuisance.
- Adding __init__.py to satisfy mypy, which otherwise considers the lit_autoupdate.py scripts to be issues.
- Using py because I was thinking sh would be more platform-dependent. py should port better to Windows.
- Getting rid of [[ID#]] capture groups in the semantics-ir tests because with the autoupdate it's kind of moot (also, hard to autogenerate the pairs without relying on the %### value).
Note this does mean tests switch to more of a "make a change, see which tests change" setup. I don't know that that's a _bad_ thing though -- it's pretty much how tests are being written right now, which is why I went down this rabbit hole. It's a nuisance to make a change then _manually_ have to update a bunch of code.
My intent is to use this for to convert parse-tree tests to lit, but I wanted to do this with _existing_ tests first as a proof of concept and to make sure there's agreement.
Implements basic support for rewrite constraints as proposed in #2173.
Support for associated constants and complex constraints in general is also made more robust: argument deduction now properly computes and substitutes witnesses, and interface declarations track a more correct description of the constraint that they introduce than the one we previously built.
Change explorer's handling of witnesses to track them wherever possible. Associated constant support needs witnesses to be available much more pervasively.
The main changes here are:
- `Substitute` now takes a set of bindings covering both `Value`s for `GenericBinding`s and `Witness`es for `ImplBinding`s, and substitutes both.
- Witnesses are now tracked within `ConstraintType`s. The `.Self` type has an `ImplBinding` that self-references from parts of the constraint to other parts of the constraint can use to access the witness for the constraint.
- The constraint type for an `impl` and for a `GenericBinding` are now stored in pre-substituted form, with references to the actual constrained type rather than symbolic references to `.Self`. This results in minor changes in diagnostic text.
Argument deduction still performs substitutions without remapping witnesses.
On #2224 @zygoloid pointed out we needed --implicit-check-not to ensure we were correctly matching output. This is the standard way we're writing explorer tests, so I was looking at unifying our lit approaches.
This is one take on it, making more use of substitutions to bring various testing into alignment, as well as symlinks to avoid config skew (maybe I'll eventually figure out a better solution than symlinks).
Makes a couple small fixes in explorer to remove end-of-line whitespace on output.
1) toolchain and explorer use the same working dir logic, share it
2) explorer's carbon.cpp and main_bin.cpp use the same relative path logic, share it
3) You can append a longer path in one call with the right kind of iterator
4) Fix what's maybe a bug in passing `relative_prelude_path.str()` to `cl::init`
5) Collapse Main and ExplorerMain to avoid passing more parameters between
The only usage of this set is to include this list in trace output when
tracing type-checking of patterns. But that in turn seems arbitrary and
not useful.
Previously explorer worked under `bazel run` but not when run directly, because it was finding the prelude relative to the current working directory. Now it looks for it relative to the location of the binary, so it works both when run directly and when run with `bazel run`.
Adrien Leravat
Chandler Carruth
Richard Smith
Jon Ross-Perkins
Kareem Ergawyandergawy