Reworked handling of implicit inline marking for member and friend
function defined in class.
Now, we handle it in an additive manner, i.e. if such in-class functions
are inline implicitly by language rules,
we mark the as `setImplicitInline`, and perform no action otherwise.
As we never remove inline specifier, the implementation is orthogonal to
other sources of inline
(like `inline`, `constexpr`, e.t.c), and we do not need to handle them
specially.
Also included test for `constexpr`, `consteval` and global module cases.
Currently, clang rejects the following explicit specialization of `f`
due to the constraints not being equivalent:
```
template<typename T>
struct A
{
template<bool B>
void f() requires B;
};
template<>
template<bool B>
void A<int>::f() requires B { }
```
This happens because, in most cases, we do not set the flag indicating
whether a `RedeclarableTemplate` is an explicit specialization of a
member of an implicitly instantiated class template specialization until
_after_ we compare constraints for equivalence. This patch addresses the
issue (and a number of other issues) by:
- storing the flag indicating whether a declaration is a member
specialization on a per declaration basis, and
- significantly refactoring `Sema::getTemplateInstantiationArgs` so we
collect the right set of template argument in all cases.
Many of our declaration matching & constraint evaluation woes can be
traced back to bugs in `Sema::getTemplateInstantiationArgs`. This
change/refactor should fix a lot of them. It also paves the way for
fixing #101330 and #105462 per my suggestion in #102267 (which I have
implemented on top of this patch but will merge in a subsequent PR).
Basically clang already implemented 90% of the feature as an extension.
This commit disables warnings for C23 and aligns types of enumerators
according to the recent wording.
Fixes#80235
When trying to overload a function within `extern "C"`, the diagnostic
`functions that differ only in their return type cannot be overloaded`
is given. This diagnostic is inappropriate because overloading is
basically not allowed in the C language. However, if the redeclared
function has the `((overloadable))` attribute, it should be diagnosed as
`functions that differ only in their return type cannot be overloaded`.
This patch uses `isExternC()` to provide an appropriate diagnostic
during the diagnostic process. `isExternC()` updates the linkage
information cache internally, so calling it before merging functions can
cause clang to crash. An example is declaring `static void foo()` and
`void foo()` within an `extern "C"` block. Therefore, I decided to call
`isExternC()` after the compilation error is confirmed and select the
diagnostic message. The diagnostic message is `conflicting types for
'func'` similar to the diagnostic in C, and `functions that differ only
in their return type cannot be overloaded` if the `((overloadable))`
attribute is given.
Regression tests verify that the expected diagnostics are given when
trying to overload functions within `extern "C"` and when the
`((overloadable))` attribute is present.
---------
Co-authored-by: Sirraide <aeternalmail@gmail.com>
HLSL output parameters are denoted with the `inout` and `out` keywords
in the function declaration. When an argument to an output parameter is
constructed a temporary value is constructed for the argument.
For `inout` pamameters the argument is initialized via copy-initialization
from the argument lvalue expression to the parameter type. For `out`
parameters the argument is not initialized before the call.
In both cases on return of the function the temporary value is written
back to the argument lvalue expression through an implicit assignment
binary operator with casting as required.
This change introduces a new HLSLOutArgExpr ast node which represents
the output argument behavior. The OutArgExpr has three defined children:
- An OpaqueValueExpr of the argument lvalue expression.
- An OpaqueValueExpr of the copy-initialized parameter.
- A BinaryOpExpr assigning the first with the value of the second.
Fixes#87526
---------
Co-authored-by: Damyan Pepper <damyanp@microsoft.com>
Co-authored-by: John McCall <rjmccall@gmail.com>
Control flow analysis performed by a static analysis tool revealed the
potential for null pointer dereferences to occur in conjunction with the
`Init` parameter in `Sema::AddInitializerToDecl()`. On entry to the
function, `Init` is required to be non-null as there are multiple
potential branches that unconditionally dereference it. However, there
were two places where `Init` is compared to null thus implying that
`Init` is expected to be null in some cases. These checks appear to be
purely defensive checks and thus unnecessary. Further, there were
several cases where code checked `Result`, a variable of type
`ExprResult`, for an invalid value, but did not check for a valid but
null value and then proceeded to unconditionally dereference the
potential null result. This change elides the unnecessary defensive
checks and changes some checks for an invalid result to instead branch
on an unusable result (either an invalid result or a valid but null
result).
With this patch, clang now automatically adds
``[[clang::lifetimebound]]`` to the parameters of `std::span,
std::string_view` constructors, this enables Clang to capture more cases
where the returned reference outlives the object.
Fixes#100567
We need to rebuild the template parameters of out-of-line
definitions/specializations of member templates in the context of the
current instantiation for the purposes of declaration matching. We
already do this for function templates and class templates, but not
variable templates, partial specializations of variable template, and
partial specializations of class templates. This patch fixes the latter
cases.
Previously, `[[clang::lifetimebound]]` applied to an explicit object
member function did nothing and was silently ignored.
Now issue the error diagnostic `'lifetimebound' attribute cannot be
applied; explicit object member function has no implicit object
parameter`
When various `Sema*.h` and `Sema*.cpp` files were created, cleanup of
`Sema.h` includes and forward declarations was left for the later.
Now's the time. This commit touches `Sema.h` and Sema components:
1. Unused includes are removed.
2. Unused forward declarations are removed.
3. Missing includes are added (those files are largely IWYU-clean now).
4. Includes were converted into forward declarations where possible.
As this commit focuses on headers, all changes to `.cpp` files were
minimal, and were aiming at keeping everything buildable.
Reland https://github.com/llvm/llvm-project/pull/75912
The differences of this PR between
https://github.com/llvm/llvm-project/pull/75912 are:
- Fixed a regression in `Decl::isInAnotherModuleUnit()` in DeclBase.cpp
pointed by @mizvekov and add the corresponding test.
- Fixed the regression in windows
https://github.com/llvm/llvm-project/issues/97447. The changes are in
`CodeGenModule::getVTableLinkage` from
`clang/lib/CodeGen/CGVTables.cpp`. According to the feedbacks from MSVC
devs, the linkage of vtables won't affected by modules. So I simply
skipped the case for MSVC.
Given this is more or less fundamental to the use of modules. I hope we
can backport this to 19.x.
A class member named by an expression in a member function that may instantiate to a static _or_ non-static member is represented by a `UnresolvedLookupExpr` in order to defer the implicit transformation to a class member access expression until instantiation. Since `ASTContext::getDecltypeType` only creates a `DecltypeType` that has a `DependentDecltypeType` as its canonical type when the operand is instantiation dependent, and since we do not transform types unless they are instantiation dependent, we need to mark the `UnresolvedLookupExpr` as instantiation dependent in order to correctly build a `DecltypeType` using the expression as its operand with a `DependentDecltypeType` canonical type. Fixes#99873.
The selection of the most constrained candidate for member function
explicit specializations introduced in #88963 does not check whether the
selected candidate is more constrained than all other candidates, which
can result in ambiguities being undiagnosed. This patch addresses the
issue.
HLSL has a set of intangible types which are described in in the
[draft HLSL Specification
(**[Basic.types]**)](https://microsoft.github.io/hlsl-specs/specs/hlsl.pdf):
There are special implementation-defined types such as handle types,
which fall into a category of standard intangible types. Intangible
types are types that have no defined object representation or value
representation, as such the size is unknown at compile time.
A class type T is an intangible class type if it contains an base
classes or members of intangible class type, standard intangible type,
or arrays of such types. Standard intangible types and intangible class
types are collectively called intangible
types([9](https://microsoft.github.io/hlsl-specs/specs/hlsl.html#Intangible)).
This PR implements one standard intangible type `__hlsl_resource_t`
and sets up the infrastructure that will make it easier to add more
in the future, such as samplers or raytracing payload handles. The
HLSL intangible types are declared in
`clang/include/clang/Basic/HLSLIntangibleTypes.def` and this file is
included with related macro definition in most places that require edits
when a new type is added.
The new types are added as keywords and not typedefs to make sure they
cannot be redeclared, and they can only be declared in builtin implicit
headers. The `__hlsl_resource_t` type represents a handle to a memory
resource and it is going to be used in builtin HLSL buffer types like this:
template <typename T>
class RWBuffer {
[[hlsl::contained_type(T)]]
[[hlsl::is_rov(false)]]
[[hlsl::resource_class(uav)]]
__hlsl_resource_t Handle;
};
Part 1/3 of llvm/llvm-project#90631.
---------
Co-authored-by: Justin Bogner <mail@justinbogner.com>
* Allow arm-streaming if all the functions versions adhere to it.
* Allow arm-streaming-compatible if all the functions versions adhere to
it.
When the caller needs to toggle the streaming mode all the function
versions of the callee must adhere to the same mode, otherwise the call
will yield a runtime error.
Imagine the versions of the callee live in separate TUs. The version
that is visible to the caller will determine the calling convention used
when generating code for the callsite. Therefore we cannot support
mixing streaming with non-streaming function versions. Imagine TU1 has a
streaming caller and calls foo._sme which is streaming-compatible. The
codegen for the callsite will not switch off the streaming mode. Then in
TU2 we have a version which is non-streaming and could potentially be
called in streaming mode. Similarly if the caller is non-streaming and
the called version is streaming-compatible the codegen for the callsite
will not switch on the streaming mode, but other versions may be
streaming.
Emission status seems to be only used by cuda/openmp/hip compiles, to
figure out
when to emit diagnostics. Current logic emits "uknown" when definition
is
missing, so i extended that to skipped-function-bodies as well.
I believe this is what the original commit (33e022650adee965c65f9aea086ee74f3fd1bad5) was trying to do.
This fixes a bug where clang removes the attribute from a declaration that follows a declaration directly contained in a linkage-specification.
rdar://61865848
Close https://github.com/llvm/llvm-project/issues/98583
Currently, clang will reject the following code:
```
export module mod;
extern "C++" void func();
export extern "C++" {
void func();
}
```
while both MSVC and GCC accept it. Although clang's behavior matches the
current wording, from the discussion, the consensus is that we should
accept the above example from the intention. Since the intention to not
allow export redeclaration which is not exported is to make the linkage
clear. But it doesn't matter with the declarations within global module.
Summary:
There is no sense to report these cases as an error or add `inline`
explicitly in these cases, if it is not required in normal headers.
Similar to #60079.
Test Plan: check-clang
This reverts commit 18f3bcbb13ca83d33223b00761d8cddf463e9ffb, 15bb02650e26875c48889053d6a9697444583721 and
99873b35da7ecb905143c8a6b8deca4d4416f1a9.
See the post commit message in
https://github.com/llvm/llvm-project/pull/75912 to see the reasons.
When BPF object files are linked with bpftool, every symbol must be
accompanied by BTF info. Ensure that extern functions referenced by
global variable initializers are included in BTF.
The primary motivation is "static" initialization of PROG maps:
```c
extern int elsewhere(struct xdp_md *);
struct {
__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
__uint(max_entries, 1);
__type(key, int);
__type(value, int);
__array(values, int (struct xdp_md *));
} prog_map SEC(".maps") = { .values = { elsewhere } };
```
BPF backend needs debug info to produce BTF. Debug info is not
normally generated for external variables and functions. Previously, it
was solved differently for variables (collecting variable declarations
in ExternalDeclarations vector) and functions (logic invoked during
codegen in CGExpr.cpp).
This patch generalises ExternalDefclarations to include both function
and variable declarations. This change ensures that function references
are not missed no matter the context. Previously external functions
referenced in constant expressions lacked debug info.
Fixes a crash and cleans up some dead code.
namespace Foo {
int bar();
__attribute((target_version("default"))) int bar() { return 0; }
__attribute((target_version("mops"))) int bar() { return 1; }
}
$ clang++ --target=aarch64-linux-gnu --rtlib=compiler-rt fmv.cpp
None multiversion type isn't valid here
UNREACHABLE executed at clang/lib/CodeGen/CodeGenModule.cpp:1840! ...
getMangledNameImpl
clang::CodeGen::CodeGenModule::getMangledName
clang::CodeGen::CodeGenModule::EmitGlobal
This patch moves documentation of `Sema` functions from `.cpp` files to `Sema.h` when there was no documentation in the latter, or it can be trivially subsumed. More complicated cases when there's less trivial divergence between documentation attached to declaration and the one attached to implementation are left for a later PR that would require review.
It appears that doxygen can find the documentation for a function defined out-of-line even if it's attached to an implementation, and not declaration. But other tools, e.g. clangd, are not as powerful. So this patch significantly improves autocompletion experience for (at least) clangd-based IDEs.
Introduce `nonblocking` and `nonallocating` attributes. RFC is here:
https://discourse.llvm.org/t/rfc-nolock-and-noalloc-attributes/76837
This PR introduces the attributes, with some changes in Sema to deal
with them as extensions to function (proto)types.
There are some basic type checks, most importantly, a warning when
trying to spoof the attribute (implicitly convert a function without the
attribute to one that has it).
A second, follow-on pull request will introduce new caller/callee
verification.
---------
Co-authored-by: Doug Wyatt <dwyatt@apple.com>
Co-authored-by: Shafik Yaghmour <shafik.yaghmour@intel.com>
Co-authored-by: Aaron Ballman <aaron@aaronballman.com>
Co-authored-by: Sirraide <aeternalmail@gmail.com>
This patch extracts the logci to decide how we decide the module units
belongs to the same module into a member function of ASTContext. This is
helpful to refactor the implementation in the future.
According to [temp.expl.spec] p2:
> The declaration in an _explicit-specialization_ shall not be an
_export-declaration_. An explicit specialization shall not use a
_storage-class-specifier_ other than `thread_local`.
Clang partially implements this, but a number of issues exist:
1. We don't diagnose class scope explicit specializations of variable
templates with _storage-class-specifiers_, e.g.
```
struct A
{
template<typename T>
static constexpr int x = 0;
template<>
static constexpr int x<void> = 1; // ill-formed, but clang accepts
};
````
2. We incorrectly reject class scope explicit specializations of
variable templates when `static` is not used, e.g.
```
struct A
{
template<typename T>
static constexpr int x = 0;
template<>
constexpr int x<void> = 1; // error: non-static data member cannot be
constexpr; did you intend to make it static?
};
````
3. We don't diagnose dependent class scope explicit specializations of
function templates with storage class specifiers, e.g.
```
template<typename T>
struct A
{
template<typename U>
static void f();
template<>
static void f<int>(); // ill-formed, but clang accepts
};
````
This patch addresses these issues as follows:
- # 1 is fixed by issuing a diagnostic when an explicit
specialization of a variable template has storage class specifier
- # 2 is fixed by considering any non-function declaration with any
template parameter lists at class scope to be a static data member. This
also allows for better error recovery (it's more likely the user
intended to declare a variable template than a "field template").
- # 3 is fixed by checking whether a function template explicit
specialization has a storage class specifier even when the primary
template is not yet known.
One thing to note is that it would be far simpler to diagnose this when
parsing the _decl-specifier-seq_, but such an implementation would
necessitate a refactor of `ParsedTemplateInfo` which I believe to be
outside the scope of this patch.
