1193 Commits

Author SHA1 Message Date
cor3ntin
64ffe64d2d
[Clang] Handle sema of noexcept condition in their evaluation context. (#67538)
The conditions of a noexcept and explicit specifier are full
expressions. Before this patch, we would call ActOnFinishFullExpr on
these in the context of the enclosing expression, which would cause the
collect of odr-used variables (and subsequently capture attempts) in the
wrong (enclosing) context.

This was observable when parsing the noexcept specifier condition of a
lambda appearing in a wider full expression odr-using variables.

Fixes #67492
2023-09-28 08:25:30 +02:00
Sam McCall
880fa7faa9 Revert "[clang][SemaCXX] Diagnose tautological uses of consteval if and is_constant_evaluated"
This reverts commit 491b2810fb7fe5f080fa9c4f5945ed0a6909dc92.

This change broke valid code and generated incorrect diagnostics, see
https://reviews.llvm.org/D155064
2023-09-27 18:58:01 +02:00
Takuya Shimizu
491b2810fb [clang][SemaCXX] Diagnose tautological uses of consteval if and is_constant_evaluated
This patch makes clang diagnose extensive cases of consteval if and is_constant_evaluated usage that are tautologically true or false.
This introduces a new IsRuntimeEvaluated boolean flag to Sema::ExpressionEvaluationContextRecord that means the immediate appearance of if consteval or is_constant_evaluated are tautologically false(e.g. inside if !consteval {} block or non-constexpr-qualified function definition body)
This patch also pushes new expression evaluation context when parsing the condition of if constexpr and initializer of constexpr variables so that Sema can be aware that the use of consteval if and is_consteval are tautologically true in if constexpr condition and constexpr variable initializers.
BEFORE this patch, the warning for is_constant_evaluated was emitted from constant evaluator. This patch moves the warning logic to Sema in order to diagnose tautological use of is_constant_evaluated in the same way as consteval if.

This patch separates initializer evaluation context from InitializerScopeRAII.
This fixes a bug that was happening when user takes address of function address in initializers of non-local variables.

Fixes https://github.com/llvm/llvm-project/issues/43760
Fixes https://github.com/llvm/llvm-project/issues/51567

Reviewed By: cor3ntin, ldionne
Differential Revision: https://reviews.llvm.org/D155064
2023-09-27 09:26:06 +09:00
Shafik Yaghmour
6eadc8f16e [Clang] Fix crash in Parser::ParseDirectDeclarator by adding check that token is not an annotation token
In Parser::ParseDirectDeclarator(...) in some cases ill-formed code can cause an
annotation token to end up where it was not expected. The fix is to add a
!Tok.isAnnotation() guard before attempting to access identifier info.

This fixes: https://github.com/llvm/llvm-project/issues/64836

Differential Revision: https://reviews.llvm.org/D158804
2023-09-12 11:06:06 -07:00
Yaxun (Sam) Liu
9b7763821a
Reland "[CUDA][HIP] Fix overloading resolution in global var init" (#65606)
https://reviews.llvm.org/D158247 caused regressions for HIP on Windows
and was reverted.

A reduced test case is:

```
typedef void (__stdcall* funcTy)();
void invoke(funcTy f);

static void __stdcall callee() noexcept {
}

void foo() {
   invoke(callee);
}
```

It is due to clang missing handling host/device attributes for calling
convention at a few places

This patch fixes that.
2023-09-07 23:18:30 -04:00
Yaxun (Sam) Liu
27313b68ef Revert "[CUDA][HIP] Fix overloading resolution in global variable initializer"
This reverts commit de0df639724b10001ea9a74539381ea494296be9.

It was reverted due to regression in HIP unit test on Windows:

 In file included from C:\hip-tests\catch\unit\graph\hipGraphClone.cc:37:

 In file included from C:\hip-tests\catch\.\include\hip_test_common.hh:24:

 In file included from C:\hip-tests\catch\.\include/hip_test_context.hh:24:

 In file included from C:/install/native/Release/x64/hip/include\hip/hip_runtime.h:54:

 C:/dk/win\vc\14.31.31107\include\thread:76:70: error: cannot initialize a parameter of type '_beginthreadex_proc_type' (aka 'unsigned int (*)(void *) __attribute__((stdcall))') with an lvalue of type 'const unsigned int (*)(void *) noexcept __attribute__((stdcall))': different exception specifications

    76 |             reinterpret_cast<void*>(_CSTD _beginthreadex(nullptr, 0, _Invoker_proc, _Decay_copied.get(), 0, &_Thr._Id));

       |                                                                      ^~~~~~~~~~~~~

 C:\hip-tests\catch\unit\graph\hipGraphClone.cc:290:21) &>' requested here

    90 |         _Start(_STD forward<_Fn>(_Fx), _STD forward<_Args>(_Ax)...);

       |         ^

 C:\hip-tests\catch\unit\graph\hipGraphClone.cc:290:21) &, 0>' requested here

   311 |     std::thread t(lambdaFunc);

       |                 ^

 C:/dk/win\ms_wdk\e22621\Include\10.0.22621.0\ucrt\process.h:99:40: note: passing argument to parameter '_StartAddress' here

    99 |     _In_      _beginthreadex_proc_type _StartAddress,

       |                                        ^

 1 error generated when compiling for gfx1030.
2023-08-31 09:02:49 -04:00
Sergei Barannikov
a7eaaba699 [Parser] Parse string literal arguments of 'availability', 'external_source_symbol' and 'uuid' attributes as unevaluated
This is a complementary to D156237.
These attributes have custom parsing logic.

Reviewed By: cor3ntin

Differential Revision: https://reviews.llvm.org/D159024
2023-08-30 11:46:54 +03:00
Yaxun (Sam) Liu
de0df63972 [CUDA][HIP] Fix overloading resolution in global variable initializer
Currently, clang does not resolve certain overloaded functions correctly in the initializer
of global variables, e.g.

template<typename T1, typename U>
T1 mypow(T1, U);

__attribute__((device)) double mypow(double, int);

double t_extent = mypow(1.0, 2);

In the above example, mypow is supposed to resolve to the host version
but clang resolves it to the device version instead, and emits an error
(https://godbolt.org/z/17xxzaa67).

However, if the variable is assigned in a host function, there is no error.
The discrepancy in overloading resolution inside and outside of
a function is due to clang not accounting for the host/device target
when resolving functions called in the initializer of a global variable.

This patch introduces a global host/device target context for CUDA/HIP
for functions called outside of functions. For global variable initialization,
it is determined by the host/device attribute of the variable. For other
situations, a default value of host_device is sufficient.

Reviewed by: Artem Belevich

Differential Revision: https://reviews.llvm.org/D158247

Fixes: SWDEV-416731
2023-08-29 10:17:24 -04:00
Fred Fu
79af92bb99 Reland "[clang-repl] support code completion at a REPL."
Original commit message:
"
This patch enabled code completion for ClangREPL. The feature was built upon
three existing Clang components: a list completer for LineEditor, a
CompletionConsumer from SemaCodeCompletion, and the ASTUnit::codeComplete method.
The first component serves as the main entry point of handling interactive inputs.

Because a completion point for a compiler instance has to be unchanged once it
is set, an incremental compiler instance is created for each code
completion. Such a compiler instance carries over AST context source from the
main interpreter compiler in order to obtain declarations or bindings from
previous input in the same REPL session.

The most important API codeComplete in Interpreter/CodeCompletion is a thin
wrapper that calls with ASTUnit::codeComplete with necessary arguments, such as
a code completion point and a ReplCompletionConsumer, which communicates
completion results from SemaCodeCompletion back to the list completer for the
REPL.

In addition, PCC_TopLevelOrExpression and CCC_TopLevelOrExpression` top levels
were added so that SemaCodeCompletion can treat top level statements like
expression statements at the REPL. For example,

clang-repl> int foo = 42;
clang-repl> f<tab>

From a parser's persective, the cursor is at a top level. If we used code
completion without any changes, PCC_Namespace would be supplied to
Sema::CodeCompleteOrdinaryName, and thus the completion results would not
include foo.

Currently, the way we use PCC_TopLevelOrExpression and
CCC_TopLevelOrExpression is no different from the way we use PCC_Statement
and CCC_Statement respectively.

Differential revision: https://reviews.llvm.org/D154382
"

The new patch also fixes clangd and several memory issues that the bots reported
and upload the missing files.
2023-08-28 20:09:03 +00:00
Vassil Vassilev
752f87cd6a Revert "Reland "[clang-repl] support code completion at a REPL.""
This reverts commit 5ab25a42ba70c4b50214b0e78eaaccd30696fa09 due to forgotten
files.
2023-08-28 20:05:14 +00:00
Fred Fu
5ab25a42ba Reland "[clang-repl] support code completion at a REPL."
Original commit message:
"
This patch enabled code completion for ClangREPL. The feature was built upon
three existing Clang components: a list completer for LineEditor, a
CompletionConsumer from SemaCodeCompletion, and the ASTUnit::codeComplete method.
The first component serves as the main entry point of handling interactive inputs.

Because a completion point for a compiler instance has to be unchanged once it
is set, an incremental compiler instance is created for each code
completion. Such a compiler instance carries over AST context source from the
main interpreter compiler in order to obtain declarations or bindings from
previous input in the same REPL session.

The most important API codeComplete in Interpreter/CodeCompletion is a thin
wrapper that calls with ASTUnit::codeComplete with necessary arguments, such as
a code completion point and a ReplCompletionConsumer, which communicates
completion results from SemaCodeCompletion back to the list completer for the
REPL.

In addition, PCC_TopLevelOrExpression and CCC_TopLevelOrExpression` top levels
were added so that SemaCodeCompletion can treat top level statements like
expression statements at the REPL. For example,

clang-repl> int foo = 42;
clang-repl> f<tab>

From a parser's persective, the cursor is at a top level. If we used code
completion without any changes, PCC_Namespace would be supplied to
Sema::CodeCompleteOrdinaryName, and thus the completion results would not
include foo.

Currently, the way we use PCC_TopLevelOrExpression and
CCC_TopLevelOrExpression is no different from the way we use PCC_Statement
and CCC_Statement respectively.

Differential revision: https://reviews.llvm.org/D154382
"

The new patch also fixes clangd and several memory issues that the bots reported.
2023-08-28 19:59:56 +00:00
Vassil Vassilev
f94a937cb3 Revert "[clang-repl] support code completion at a REPL."
This reverts commit eb0e6c3134ef6deafe0a4958e9e1a1214b3c2f14 due to failures in
clangd such as https://lab.llvm.org/buildbot/#/builders/57/builds/29377
2023-08-23 14:46:15 +00:00
Fred Fu
eb0e6c3134 [clang-repl] support code completion at a REPL.
This patch enabled code completion for ClangREPL. The feature was built upon
three existing Clang components: a list completer for LineEditor, a
CompletionConsumer from SemaCodeCompletion, and the ASTUnit::codeComplete method.
The first component serves as the main entry point of handling interactive inputs.

Because a completion point for a compiler instance has to be unchanged once it
is set, an incremental compiler instance is created for each code
completion. Such a compiler instance carries over AST context source from the
main interpreter compiler in order to obtain declarations or bindings from
previous input in the same REPL session.

The most important API codeComplete in Interpreter/CodeCompletion is a thin
wrapper that calls with ASTUnit::codeComplete with necessary arguments, such as
a code completion point and a ReplCompletionConsumer, which communicates
completion results from SemaCodeCompletion back to the list completer for the
REPL.

In addition, PCC_TopLevelOrExpression and CCC_TopLevelOrExpression` top levels
were added so that SemaCodeCompletion can treat top level statements like
expression statements at the REPL. For example,

clang-repl> int foo = 42;
clang-repl> f<tab>

From a parser's persective, the cursor is at a top level. If we used code
completion without any changes, PCC_Namespace would be supplied to
Sema::CodeCompleteOrdinaryName, and thus the completion results would not
include foo.

Currently, the way we use PCC_TopLevelOrExpression and
CCC_TopLevelOrExpression is no different from the way we use PCC_Statement
and CCC_Statement respectively.

Differential revision: https://reviews.llvm.org/D154382
2023-08-23 14:00:59 +00:00
Kadir Cetinkaya
373fcd5d73
[clang] Use RecoveryExprs for broken defaultargs, instead of OpaqueValueExprs
This makes sure we can preserve invalid-ness for consumers of this
node, it prevents crashes. It also aligns better with rest of the places that
store invalid expressions.

Differential Revision: https://reviews.llvm.org/D157868
2023-08-16 10:22:16 +02:00
Corentin Jabot
98322d3eb4 Complete the implementation of P2361 Unevaluated string literals
The attributes changes were left out of Clang 17.
Attributes that used to take a string literal now accept an unevaluated
string literal instead, which means they reject numeric escape sequences
and strings literal with an encoding prefix - but the later was already
ill-formed in most cases.

We need to know that we are going to parse an unevaluated string literal
before we do - so we can reject numeric escape sequence,
so we derive from Attrs.td which attributes parameters are expected
to be string literals.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D156237
2023-08-15 14:13:13 +02:00
Aaron Ballman
9c4ade0623 [C23] Rename C2x->C23 in diagnostics
This renames C2x to C23 in diagnostic identifiers and messages. The
changes were made mechanically.
2023-08-11 08:42:01 -04:00
Aaron Ballman
0ce056a814 [C23] Rename C2x -> C23; NFC
This does the rename for most internal uses of C2x, but does not rename
or reword diagnostics (those will be done in a follow-up).

I also updated standards references and citations to the final wording
in the standard.
2023-08-11 07:43:43 -04:00
Corentin Jabot
a8bef8865e [Clang] Implement P2169 A nice placeholder with no name
This is a C++ feature that allows the use of `_` to
declare multiple variable of that name in the same scope;
these variables can then not be referred to.

In addition, while P2169 does not extend to parameter
declarations, we stop warning on unused parameters of that name,
for consistency.

The feature is backported to all C++ language modes.

Reviewed By: #clang-language-wg, aaron.ballman

Differential Revision: https://reviews.llvm.org/D153536
2023-08-04 16:51:15 +02:00
Mariya Podchishchaeva
4a792e06e8 [clang] Fix new-expression with elaborated-type-specifier
Expressions like
```
struct A {};
...
new struct A {};
struct A* b = (1 == 1) ? new struct A : new struct A;

```
were parsed as redefinitions of `struct A` and failed, however as clarified by
`CWG2141` new-expression cannot define a type, so both these examples
should be considered as references to the previously declared `struct A`.
The patch adds a "new" kind context for parsing declaration specifiers in
addition to already existing declarator context in order to track that
the parser is inside of a new expression.

Fixes https://github.com/llvm/llvm-project/issues/34341

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D153857
2023-07-03 06:07:04 -04:00
Corentin Jabot
d9be8a8a99 [Clang] Allow omitting typename in befriended constructors parameters
Fixes #63119

Reviewed By: #clang-language-wg, aaron.ballman

Differential Revision: https://reviews.llvm.org/D152242
2023-06-06 15:04:47 +02:00
Richard Sandiford
33ee5c4663 [clang] Add Parse and Sema support for RegularKeyword attributes
This patch adds the Parse and Sema support for RegularKeyword attributes,
following on from a previous patch that added Attr.td support.

The patch is quite large.  However, nothing outside the tests is
specific to the first RegularKeyword attribute (__arm_streaming).
The patch should therefore be a one-off, up-front cost.  Other
attributes just need an entry in Attr.td and the usual Sema support.

The approach taken in the patch is that the keywords can be used with
any language version.  If standard attributes were added in language
version Y, the keyword rules for version X<Y are the same as they were
for version Y (to the extent possible).  Any extensions beyond Y are
handled in the same way for both keywords and attributes.  This ensures
that existing C++11 successors like C++17 are not treated differently
from versions that have yet to be defined.

Some notes on the implementation:

* The patch emits errors rather than warnings for diagnostics that
relate to keywords.

* Where possible, the patch drops “attribute” from diagnostics
relating to keywords.

* One exception to the previous point is that warnings about C++
extensions do still mention attributes.  The use there seemed OK
since the diagnostics are noting a change in the production rules.

* If a diagnostic string needs to be different for keywords and
attributes, the patch standardizes on passing the attribute/
name/token followed by 0 for attributes and 1 for keywords.

* Although the patch updates warn_attribute_wrong_decl_type_str,
warn_attribute_wrong_decl_type, and warn_attribute_wrong_decl_type,
only the error forms of these strings are used for keywords.

* I couldn't trigger the warnings in checkUnusedDeclAttributes,
even for existing attributes.  An assert on the warnings caused
no failures in the testsuite.  I think in practice all standard
attributes would be diagnosed before this.

* The patch drops a call to standardAttributesAllowed in
ParseFunctionDeclarator.  This is because MaybeParseCXX11Attributes
checks the same thing itself, where appropriate.

* The new tests are based on c2x-attributes.c and
cxx0x-attributes.cpp.  The C++ test also incorporates a version of
cxx11-base-spec-attributes.cpp.  The FIXMEs are carried across from
the originals.

Differential Revision: https://reviews.llvm.org/D148702
2023-05-31 10:43:10 +01:00
yronglin
f75b73549d [Clang][Attribute] Improve the AST/diagnoses fidelity of alignas and _Alignas
- Fix diagnoses when the argument to `alignas` or `_Alignas` is an incomplete type.

Before:
```
./alignas.cpp:1:15: error: invalid application of 'alignof' to an incomplete type 'void'
class alignas(void) Foo {};
             ~^~~~~
1 error generated.
```
Now:
```
./alignas.cpp:1:15: error: invalid application of 'alignas' to an incomplete type 'void'
class alignas(void) Foo {};
             ~^~~~~
1 error generated.
```

- Improve the AST fidelity of `alignas` and `_Alignas` attribute.

Before:
```
AlignedAttr 0x13f07f278 <col:7> alignas
    `-ConstantExpr 0x13f07f258 <col:15, col:21> 'unsigned long'
      |-value: Int 8
      `-UnaryExprOrTypeTraitExpr 0x13f07f118 <col:15, col:21> 'unsigned long' alignof 'void *'
```

Now:
```
AlignedAttr 0x14288c608 <col:7> alignas 'void *'
```

Reviewed By: erichkeane

Differential Revision: https://reviews.llvm.org/D150528
2023-05-26 07:41:26 +08:00
Corentin Jabot
1b0ba1c12f [Clang] Fix parsing of (auto(x)).
Allow auto(x) to appear in a parenthesis
expression.

The pattern (auto( can appear as part of a declarator,
so the parser is modified to avoid the ambiguity,
in a way consistent with the proposed resolution to CWG1223.

Reviewed By: aaron.ballman, #clang-language-wg

Differential Revision: https://reviews.llvm.org/D149276
2023-05-20 13:22:58 +02:00
Jun Zhang
247fa04116
[clang] Add a new annotation token: annot_repl_input_end
This patch is the first part of the below RFC:
https://discourse.llvm.org/t/rfc-handle-execution-results-in-clang-repl/68493

It adds an annotation token which will replace the original EOF token
when we are in the incremental C++ mode. In addition, when we're
parsing an ExprStmt and there's a missing semicolon after the
expression, we set a marker in the annotation token and continue
parsing.

Eventually, we propogate this info in ParseTopLevelStmtDecl and are able
to mark this Decl as something we want to do value printing. Below is a
example:

clang-repl> int x = 42;
clang-repl> x
// `x` is a TopLevelStmtDecl and without a semicolon, we should set
// it's IsSemiMissing bit so we can do something interesting in
// ASTConsumer::HandleTopLevelDecl.

The idea about annotation toke is proposed by Richard Smith, thanks!

Signed-off-by: Jun Zhang <jun@junz.org>

Differential Revision: https://reviews.llvm.org/D148997
2023-05-16 20:10:43 +08:00
Corentin Jabot
d4a6e4c1ee Revert "[Clang] Fix parsing of (auto(x))."
This reverts commit ef47318ec3615e83c328b07341046dfb9d869414.

This patch breaks valid code https://reviews.llvm.org/D149276#4345620
2023-05-16 13:56:33 +02:00
Corentin Jabot
ef47318ec3 [Clang] Fix parsing of (auto(x)).
Allow auto(x) to appear in a parenthesis
expression.

The pattern (auto( can appear as part of a declarator,
so the parser is modified to avoid the ambiguity,
in a way consistent with the proposed resolution to CWG1223.

Reviewed By: aaron.ballman, #clang-language-wg

Differential Revision: https://reviews.llvm.org/D149276
2023-05-16 08:13:54 +02:00
Alejandro Álvarez Ayllón
b321738f71 [clang][parser] Fix namespace dropping after malformed declarations
* After a malformed top-level declaration
* After a malformed templated class method declaration

In both cases, when there is a malformed declaration, any following
namespace is dropped from the AST. This can trigger a cascade of
confusing diagnostics that may hide the original error. An example:
```
// Start #include "SomeFile.h"
template <class T>
void Foo<T>::Bar(void* aRawPtr) {
    (void)(aRawPtr);
}
// End #include "SomeFile.h"

int main() {}
```
We get the original error, plus 19 others from the standard library.
With this patch, we only get the original error.

clangd can also benefit from this patch, as namespaces following the
malformed declaration is now preserved. i.e.
```

MACRO_FROM_MISSING_INCLUDE("X")

namespace my_namespace {
    //...
}
```
Before this patch, my_namespace is not visible for auto-completion.

Differential Revision: https://reviews.llvm.org/D150258
2023-05-15 07:39:58 -04:00
Vassil Vassilev
2c4620c1da [clang-repl] Consider the scope spec in template lookups for deduction guides.
isDeductionGuideName looks up the underlying template and if the template name
is qualified we miss that qualification resulting in an error. This issue
resurfaced in clang-repl where we call isDeductionGuideName more often to
distinguish between if we had a statement or declaration.

This patch passes the CXXScopeSpec information down to LookupTemplateName to
make the lookup more precise.

Differential revision: https://reviews.llvm.org/D147319
2023-05-08 17:54:56 +00:00
David Stone
6d6880554c [clang][Sema][NFC] Move EnterExpressionEvaluationContext to its own file
Sema.h is huge. This makes a small reduction to it by moving
EnterExpressionEvaluationContext into a new header, since it is an
independent component.

Differential Revision: https://reviews.llvm.org/D149796
2023-05-04 13:06:53 -04:00
Congcong Cai
3333e12753 [clang] add diagnose when member function contains invalid default argument
Fixed: https://github.com/llvm/llvm-project/issues/62122
This change pointer to add diagnose message for this code.
```
struct S {
    static int F(int n = 0 ? 0) {
        return 0;
    }
};
```
For default parameter, we should set it as unparsed even if meeting
syntax error because it should be issued in real parser time instead of
set is as invalid directly without diagnose.

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D148372
2023-04-25 23:08:30 +02:00
Richard Sandiford
aec3f951bf [clang] Type safety tweak for AttributeCommonInfo::Form
This patch adds static functions for constructing most
AttributeCommonInfo::Forms.  Direct construction is only retained where
all fields (currently the syntax and spelling) are specified explicitly.

This is a wash on its own.  The purpose is to allow extra fields
to be added to Form without disrupting all callers.  In particular,
it allows extra information to be stored about keywords without
affecting non-keyword uses.

No functional change intended.

Differential Revision: https://reviews.llvm.org/D148104
2023-04-13 10:14:49 +01:00
Richard Sandiford
265d87e465 [clang] Allow attributes to be constructed from keyword tokens
This patch adds an extra AttributeCommonInfo::Form constructor
for keywords, represented by their TokenKind.  This isn't a
win on its own, but it helps with later patches.

No functional change intended.

Differential Revision: https://reviews.llvm.org/D148103
2023-04-13 10:14:49 +01:00
Richard Sandiford
b6d4d51f8f [clang] Specify attribute syntax & spelling with a single argument
When constructing an attribute, the syntactic form was specified
using two arguments: an attribute-independent syntax type and an
attribute-specific spelling index.  This patch replaces them with
a single argument.

In most cases, that's done using a new Form class that combines the
syntax and spelling into a single object.  This has the minor benefit
of removing a couple of constructors.  But the main purpose is to allow
additional information to be stored as well, beyond just the syntax and
spelling enums.

In the case of the attribute-specific Create and CreateImplicit
functions, the patch instead uses the attribute-specific spelling
enum.  This helps to ensure that the syntax and spelling are
consistent with each other and with the Attr.td definition.

If a Create or CreateImplicit caller specified a syntax and
a spelling, the patch drops the syntax argument and keeps the
spelling.  If the caller instead specified only a syntax
(so that the spelling was SpellingNotCalculated), the patch
simply drops the syntax argument.

There were two cases of the latter: TargetVersion and Weak.
TargetVersionAttrs were created with GNU syntax, which matches
their definition in Attr.td, but which is also the default.
WeakAttrs were created with Pragma syntax, which does not match
their definition in Attr.td.  Dropping the argument switches
them to AS_GNU too (to match [GCC<"weak">]).

Differential Revision: https://reviews.llvm.org/D148102
2023-04-13 10:14:49 +01:00
Corentin Jabot
1cdc0e83c8 [Clang] Check type-constraints applied to placeholder types
(and deduced return types)

Previously, only type constraints applied to type parameter
were semantically checked.

A diagnostic would still be emitted on instantiation, but it was
too late, lacked clarity, and was inconsistent with type parameters.

Reviewed By: erichkeane

Differential Revision: https://reviews.llvm.org/D147925
2023-04-10 17:33:09 +02:00
Corentin Jabot
abf4a8cb15 [Clang] Improve diagnostics when using a concept as template argument
When using the name of a template variable or concept in places
where an expression was expected, Clang would drop the cxxscope token
preceeding it, if any.

This leads to subpar diagnostics - complaining about the
identifier being undeclared as clang would not know to look into a
non-global scope.

We make sure the scope is preserved.

When encountering `ns::Concept foo x;`, Clang would also fail
to provide the same quality as it does at global scope.

Reviewed By: aaron.ballman, erichkeane

Differential Revision: https://reviews.llvm.org/D146719
2023-03-30 16:30:23 +02:00
Paulo Matos
8d0c889752 [clang][WebAssembly] Initial support for reference type funcref in clang
This is the funcref counterpart to 890146b. We introduce a new attribute
that marks a function pointer as a funcref. It also implements builtin
__builtin_wasm_ref_null_func(), that returns a null funcref value.

Differential Revision: https://reviews.llvm.org/D128440
2023-03-17 18:31:44 +01:00
Alexander Shaposhnikov
421c098b32 [Clang][Sema] Start fixing handling of out-of-line definitions of constrained templates
This diff starts fixing our handling of out-of-line definitions of constrained templates.
Initially it was motivated by https://github.com/llvm/llvm-project/issues/49620 and
https://github.com/llvm/llvm-project/issues/60231.
In particular, this diff adjusts Sema::computeDeclContext to work properly in the case of
constrained template parameters.

Test plan:
1/ ninja check-all
2/ Bootstrapped Clang passes all the tests
3/ Internal testing

Differential revision: https://reviews.llvm.org/D145034
2023-03-10 09:21:09 +00:00
Aaron Ballman
06174134e4 [C2x] Implement support for revised spelling of keywords
This implements WG14 N2934
(https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2934.pdf), which
adds keywords for alignas, alignof, bool, static_assert, and
thread_local in C, as aliases for _Alignas, _Alignof, _Bool,
_Static_assert, and _Thread_local. We already supported the keywords in
C2x mode, but this completes support by adding pre-C2x compat warnings
and updates the stdalign.h header in freestanding mode.
2023-02-25 09:30:10 -05:00
Alex Lorenz
c8b37e48f6 [clang] extend external_source_symbol attribute with USR clause
Allow the user to specify a concrete USR in the external_source_symbol attribute.
That will let Clang's indexer to use Swift USRs for Swift declarations that are
represented with C++ declarations.

This new clause is used by Swift when generating a C++ header representation
of a Swift module:
https://github.com/apple/swift/pull/63002

Differential Revision: https://reviews.llvm.org/D141324
2023-02-23 14:59:26 -08:00
Vassil Vassilev
159073bc0a [clang-repl] Support compound statement as a top-level statement.
This patch teaches our incremental compilation infrastructure to push and pop a
fake function scope making the Parser happy when parsing compound statements as
part of a top-leve statement declaration.

Differential revision: https://reviews.llvm.org/D139798
2023-02-17 09:09:04 +00:00
Tobias Hieta
877859a09b
[clang] Handle __declspec() attributes in using
This patch fixes so that declspec attributes are forwarded
to the alias declaration.

Before this patch this would assert:

class Test { int a; };
using AlignedTest = __declspec(align(16)) const Test;
static_assert(alignof(AlignedTest) == 16, "error");

But afterwards it behaves the same as MSVC does and doesn't
assert.

Fixes: llvm/llvm-project#60513

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D143632
2023-02-13 15:43:08 +01:00
Steven Wu
0480748ea6 [DeclContext] Sort the Decls before adding into DeclContext
Fix a non-deterministic issue in clang module generation, which the
anonymous declaration number from a function context is not
deterministic. This is due to the unstable iteration order for decls in
scope so the order after moving the decls into function decl context is
not deterministic.

From https://reviews.llvm.org/D135118, we can't use a set that preserves
the order without the performance penalty. Fix the issue by sorting the
decls based on raw encoding of their source location.

rdar://104097976

Reviewed By: akyrtzi, vsapsai

Differential Revision: https://reviews.llvm.org/D141625
2023-02-02 15:16:20 -08:00
Haojian Wu
e400c63cc3 Revert "[clang] Build UsingType for elaborated type specifiers."
This reverts commit e70ca7b35319a3621f9d9c6475926428f8c5c000 and the
followup patch "[clang] Fix the location of UsingTypeLoc"
(ebbeb164c25a40cb6ba9c6b18dce5dcd06c0bb07).

The patch causes an incorrect lookup result:

```
namespace ns { struct Foo { };}

using ns::Foo;
void test() {
  struct Foo {
  } k; // the type of k refers to ns::Foo, rather than the local Foo!
}
```
2023-01-26 11:37:41 +01:00
Haojian Wu
e70ca7b353 [clang] Build UsingType for elaborated type specifiers.
Support building UsingType for elaborated type specifiers:

```
namespace ns { class Foo {}; }

using ns::Foo;

// The TypeLoc of `Foo` below should be a ElaboratedTypeLoc with an
// inner UsingTypeLoc rather than the underlying `CXXRecordTypeLoc`
class Foo foo;
```

Differential Revision: https://reviews.llvm.org/D141280
2023-01-19 14:20:38 +01:00
Aaron Ballman
e7300e75b5 Diagnose extensions in 'offsetof'
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2350.htm made very
clear that it is an UB having type definitions with in offsetof.
Clang supports defining a type as the first argument as a conforming
extension due to how many projects use the construct in C99 and earlier
to calculate the alignment of a type. GCC also supports defining a type
as the first argument.

This adds extension warnings and documentation for the functionality
Clang explicitly supports.

Fixes #57065
Reverts the revert of 39da55e8f548a11f7dadefa73ea73d809a5f1729

Co-authored-by: Yingchi Long <i@lyc.dev>
Co-authored-by: Aaron Ballman <aaron@aaronballman.com>

Differential Revision: https://reviews.llvm.org/D133574
2023-01-18 08:51:21 -05:00
Haojian Wu
6898d8413f Reland "nullptr returned from ActOnTag() is not a valid result"
The commit was reverted in 346e1c43a11b8af5a818dac321f83f043862c1ec as
part of the f1f0a0d8e8fdd2e534d9423b2e64c6b8aaa53aee revert.
2023-01-18 12:41:44 +01:00
Arthur Eubanks
39da55e8f5 Revert "Diagnose extensions in 'offsetof'"
This reverts commit f1f0a0d8e8fdd2e534d9423b2e64c6b8aaa53aee.

Causes crashes on

$ echo 'typedef int a; void c() { __builtin_offsetof(struct {a b}, b); }' | bin/clang -cc1 -emit-llvm -o /dev/null - -x c
2023-01-17 22:35:21 -08:00
Arthur Eubanks
346e1c43a1 Revert "nullptr returned from ActOnTag() is not a valid result"
This reverts commit 3925fbc80019f72bf3f5174736f348acfb5768b0.

Dependent commit to be reverted.
2023-01-17 22:35:20 -08:00
Aaron Ballman
3925fbc800 nullptr returned from ActOnTag() is not a valid result
DeclResult tracks two states: valid/invalid and usable/unusable.
Passing a null pointer to the constructor creates a valid but unusable
result and we wanted an invalid result instead. This changes some
functions to return a DeclResult rather than a Decl * to make it harder
to get this incorrect in callers.

Discovered when working on https://reviews.llvm.org/D141280.

Co-authored-by: Haojian Wu <hokein@google.com>
Co-authored-by: Aaron Ballman <aaron@aaronballman.com>

Differential Revision: https://reviews.llvm.org/D141580
2023-01-17 16:04:35 -05:00
Aaron Ballman
f1f0a0d8e8 Diagnose extensions in 'offsetof'
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2350.htm made very
clear that it is an UB having type definitions with in offsetof.
Clang supports defining a type as the first argument as a conforming
extension due to how many projects use the construct in C99 and earlier
to calculate the alignment of a type. GCC also supports defining a type
as the first argument.

This adds extension warnings and documentation for the functionality
Clang explicitly supports.

Fixes #57065

Co-authored-by: Yingchi Long <i@lyc.dev>
Co-authored-by: Aaron Ballman <aaron@aaronballman.com>
2023-01-17 14:30:57 -05:00