The IdResolver chain is the main way for C to implement lookup rules.
Every new partial translation unit caused clang to exit the top-most
scope which in turn cleaned up the IdResolver chain. That was not an
issue for C++ because its lookup is implemented on the level of
declaration contexts.
This patch keeps the IdResolver chain across partial translation units
maintaining proper C-style lookup infrastructure.
Clang crashes when diagnosing the following invalid redeclaration in
C++11:
```
struct A {
void f();
};
constexpr void A::f() { } // crash here
```
This happens because `DiagnoseInvalidRedeclaration` tries to create a
fix-it to remove `const` from the out-of-line declaration of `f`, but
there is no `SourceLocation` for the `const` qualifier (it's implicitly
`const` due to `constexpr`) and an assert in
`FunctionTypeInfo::getConstQualifierLoc` fails.
This patch changes `DiagnoseInvalidRedeclaration` to only suggest the removal of the
`const` qualifier when it was explicitly specified in the _cv-qualifier-seq_ of the declaration.
Add `environment` parameter to Clang availability attribute. The allowed
values for this parameter are a subset of values allowed in the
`llvm::Triple` environment component. If the `environment` parameters is
present, the declared availability attribute applies only to targets
with the same platform and environment.
This new parameter will be initially used for annotating HLSL functions
for the `shadermodel` platform because in HLSL built-in function
availability can depend not just on the shader model version (mapped to
`llvm::Triple::OSType`) but also on the target shader stage (mapped to
`llvm::Triple::EnvironmentType`). See example in #89802 and
microsoft/hlsl-specs#204 for more details.
The environment parameter is currently supported only for HLSL.
Fixes#89802
Scalable types are only available when:
* The function is compiled with +sve
* The function is compiled with +sme and the function is executed in
Streaming-SVE mode.
I'm planning to remove StringRef::equals in favor of
StringRef::operator==.
- StringRef::operator==/!= outnumber StringRef::equals by a factor of
24 under clang/ in terms of their usage.
- The elimination of StringRef::equals brings StringRef closer to
std::string_view, which has operator== but not equals.
- S == "foo" is more readable than S.equals("foo"), especially for
!Long.Expression.equals("str") vs Long.Expression != "str".
With the commit d5308949cf884d8e4b971d51a8b4f73584c4adec, we now
preserve the initializer for invalid decls with the recovery-expr.
However there is a chance that the original init expr is a typo-expr, we
should not preserve it in the final AST, as typo-expr is an internal AST
node. We should use the one after the typo correction.
This is spotted by a clangd hover crash on the testcase.
Fixes#85447
---
This PR resolves a crash in `ActOnUninitializedDecl` due to an oversight
in updating the `isInvalidDecl` state before invocation. The crash
occurs due to a missing invocation of `setInvalidDecl()` for an invalid
`Anon` declaration. To address this issue, the `setInvalidDecl()` method
is now properly invoked to mark the `Anon` declaration as invalid before
running `ActOnUninitializedDecl()`.
Reapplies #84050, addressing a bug which cases a crash when an
expression with the type of the current instantiation is used as the
_postfix-expression_ in a class member access expression (arrow form).
Consider the following:
```cpp
template<typename T>
struct A
{
auto f()
{
return this->x;
}
};
```
Although `A` has no dependent base classes and the lookup context for
`x` is the current instantiation, we currently do not diagnose the
absence of a member `x` until `A<T>::f` is instantiated. This patch
moves the point of diagnosis for such expressions to occur at the point
of definition (i.e. prior to instantiation).
Add separate messages about passing arguments or returning parameters
with scalable types.
---------
Co-authored-by: Sander de Smalen <sander.desmalen@arm.com>
Attribute `optnone` must turn off all optimizations including fast-math
ones. Actually AST nodes in the 'optnone' function still had fast-math
flags. This change implements fixing FP options before function body is
parsed.
Reapplies #87541 and #88311 (again) addressing the bug which caused
expressions naming overload sets to be incorrectly rebuilt, as well as
the bug which caused base class members to always be treated as overload
sets.
The primary change since #88311 is `UnresolvedLookupExpr::Create` is called directly in `BuildPossibleImplicitMemberExpr` with `KnownDependent` as `true` (which causes the expression type to be set to `ASTContext::DependentTy`). This ensures that any further semantic analysis involving the type of the potentially implicit class member access expression is deferred until instantiation.
Try to fix https://github.com/llvm/llvm-project/issues/75221
This crash caused by calculating record layout which contains a field
declaration with dependent type. Make it invalid before it is a complete
definition to prevent this crash. Define a new scope type to record this
type alias and set the record declaration invalid when it is defined in
a type alias template.
Co-authored-by: huqizhi <836744285@qq.com>
This patch converts the enum into scoped enum, and moves it into its own header for the time being. It's definition is needed in `Sema.h`, and is going to be needed in upcoming `SemaObjC.h`. `Lookup.h` can't hold it, because it includes `Sema.h`.
The approved resolution for CWG2858 changes
[expr.prim.id.qual] p2 sentence 2 to read:
> A declarative _nested-name-specifier_ shall not have a
_computed-type-specifier_.
This patch implements the approved resolution. Since we don't consider
_nested-name-specifiers_ in friend declarations to be declarative (yet),
it currently isn't possible to write a test that would produce this
diagnostic (`diagnoseQualifiedDeclaration` is never called if the
`DeclContext` can't be computed). Nevertheless, tests were added which
will produce the diagnostic once we start calling
`diagnoseQualifiedDeclaration` for friend declarations.
The compiler doesn't know in advance if the streaming and non-streaming
vector-lengths are different, so it should be safe to give a warning
diagnostic to warn the user about possible undefined behaviour. If the
user knows the vector lengths are equal, they can disable the warning
separately.
Try to fix https://github.com/llvm/llvm-project/issues/86790
`getFETokenInfo` requires `DeclarationName` shouldn't be empty and this
will produce crash when checking name conflict of an anonymous
`NamedDecl` in `Sema::PushOnScopeChains` and whether it's a reserved
identifier or not. These wouldn't happen when it's a anonymous enum and
we can skip the checking and just add the declaration to current scope.
Co-authored-by: huqizhi <836744285@qq.com>
Emit `-Wunused-but-set-variable` warning on C++ variables whose
declaration (with initializer) entirely consist the condition expression
of a if/while/for construct but are not actually used in the body of the
if/while/for construct.
Fixes#41447
Clang erroneously rejects the following:
```
template<typename T>
struct A
{
template<typename U>
auto f();
};
template<>
template<typename U>
auto A<int>::f(); // error: conflicting types for 'f'
```
This happens because the explicit specialization of `f` has its return
type replaced with a dependent `AutoType` in `ActOnFunctionDeclarator`,
but no such replacement occurs for the implicitly instantiated function
template `A<int>::f`. Since the return types don't match, the explicit
specialization is diagnosed as an invalid redeclaration.
This patch moves the replacement of the return type to
`CheckFunctionDeclaration` so it also happens during instantiation.
`setObjectOfFriendDecl` will have been called by then, so the `isFriend
&& CurContext->isDependentContext()` condition is made redundant &
removed (as it already happens in `DeclContext::isDependentContext`).
`Sema::IsOverload` only checks the _declared_ return type (which isn't
changed by the adjustment), so adjusting the return type afterwards
should be safe.
This is now allowed in C23; continue to diagnose it in earlier language
modes as before, but now as a C23 extension rather than a GNU extension.
This fixes#83658.
Introduce `Decl::isFromExplicitGlobalModule` to replace the
`D->getOwningModule() && D->getOwningModule()->isExplicitGlobalModule()`
pattern to save some typings.
This reverts commit ca4c4a6758d184f209cb5d88ef42ecc011b11642.
This was intended not to introduce new consistency diagnostics for
smart pointer types, but failed to ignore sugar around types when
detecting this.
Fixed and test added.
GNU and MSVC have extensions where flexible array members (or their
equivalent) can be in unions or alone in structs. This is already fully
supported in Clang through the 0-sized array ("fake flexible array")
extension or when C99 flexible array members have been syntactically
obfuscated.
Clang needs to explicitly allow these extensions directly for C99
flexible arrays, since they are common code patterns in active use by
the
Linux kernel (and other projects). Such projects have been using either
0-sized arrays (which is considered deprecated in favor of C99 flexible
array members) or via obfuscated syntax, both of which complicate their
code bases.
For example, these do not error by default:
```
union one {
int a;
int b[0];
};
union two {
int a;
struct {
struct { } __empty;
int b[];
};
};
```
But this does:
```
union three {
int a;
int b[];
};
```
Remove the default error diagnostics for this but continue to provide
warnings under Microsoft or GNU extensions checks. This will allow for
a seamless transition for code bases away from 0-sized arrays without
losing existing code patterns. Add explicit checking for the warnings
under various constructions.
Additionally fixes a CodeGen bug with flexible array members in unions
in C++, which was found when adding a testcase for:
```
union { char x[]; } z = {0};
```
which only had Sema tests originally.
Fixes#84565
It is currently not possible to use "RVV type" and "RVV intrinsics" if
the "zve32x" is not enabled globally. However in some cases we may want
to use them only in some functions, for instance:
```
#include <riscv_vector.h>
__attribute__((target("+zve32x")))
vint32m1_t rvv_add(vint32m1_t v1, vint32m1_t v2, size_t vl) {
return __riscv_vadd(v1, v2, vl);
}
int other_add(int i1, int i2) {
return i1 + i2;
}
```
, it is supposed to be compilable even the vector is not specified, e.g.
`clang -target riscv64 -march=rv64gc -S test.c`.
In PR #79382, I need to add a new type that derives from
ConstantArrayType. This means that ConstantArrayType can no longer use
`llvm::TrailingObjects` to store the trailing optional Expr*.
This change refactors ConstantArrayType to store a 60-bit integer and
4-bits for the integer size in bytes. This replaces the APInt field
previously in the type but preserves enough information to recreate it
where needed.
To reduce the number of places where the APInt is re-constructed I've
also added some helper methods to the ConstantArrayType to allow some
common use cases that operate on either the stored small integer or the
APInt as appropriate.
Resolves#85124.
The latest ACLE allows it and further clarifies the following
in regards to the combination of the two attributes:
"If the `default` matches with another explicitly provided
version in the same translation unit, then the compiler can
emit only one function instead of the two. The explicitly
provided version shall be preferred."
("default" refers to the default clone here)
https://github.com/ARM-software/acle/pull/310
This was a limitation which has now been lifted. Please read the
thread below for more details:
https://github.com/llvm/llvm-project/pull/84405#discussion_r1525583647
Basically it allows to separate versioned implementations across
different TUs without having to share private header files which
contain the default declaration.
The ACLE spec has been updated accordingly to make this explicit:
"Each version declaration should be visible at the translation
unit in which the corresponding function version resides."
https://github.com/ARM-software/acle/pull/310
If a resolver is required (because there is a caller in the TU),
then a default declaration is implicitly generated.