Try to fix [issue](https://github.com/llvm/llvm-project/issues/68490 )
and some extented problem. Root cause of current issue is that error
handling in instantiation of function parameter with default
initialization on sizeof or align expression. When instance an
out-of-line template member function, depth of `TemplateTypeParmDecl` in
default initialization doesn't change while depth of other template
parameter does and this will lead to some template parameter
uninstanced. Also, sometime it will leader to wrong instantiation when
it uses the template parameter of the template class.
Fix it by add template args of context. This will make
MultiLevelTemplateArgumentList::getNumLevels matching the depth of
template parameter. Testcase with some static_assert demonstrates the
template parameter has been instanced correctly.
But, the default initialization of lambda expression compiles failed
when only checking if the member function is out-of-line. We should
check the `PrimaryFunctionTemplateDecl` of the funtion if it's
out-of-line.
Co-authored-by: huqizhi <836744285@qq.com>
This is yet another one-line patch to fix crashes on constraint
substitution.
```cpp
template <class, class> struct formatter;
template <class, class> struct basic_format_context {};
template <typename CharType>
concept has_format_function = format(basic_format_context<CharType, CharType>());
template <typename ValueType, typename CharType>
requires has_format_function<CharType>
struct formatter<ValueType, CharType> {
template <typename OutputIt>
CharType format(basic_format_context<OutputIt, CharType>);
};
```
In this case, we would build up a `RecoveryExpr` for a call within a
constraint expression due to the absence of viable functions. The
heuristic algorithm attempted to find such a function inside of a
ClassTemplatePartialSpecialization, from which we started to substitute
its requires-expression, and it succeeded with a FunctionTemplate such
that
1) It has only one parameter, which is dependent.
2) The only one parameter depends on two template parameters. They are,
in canonical form, `<template-parameter-1-0>` and
`<template-parameter-0-1>` respectively.
Before we emit an error, we still want to recover the most viable
functions. This goes downhill to deducing template parameters against
its arguments, where we would collect the argument type with the same
depth as the parameter type into a Deduced set. The size of the set is
presumed to be that of function template parameters, which is 1 in this
case. However, since we haven't yet properly set the template depth
before the dance, we'll end up putting the type for
`<template-parameter-0-1>` to the second position of Deduced set, which
is unfortunately an access violation!
The bug seems to appear since clang 12.0.
This fixes [the
case](https://github.com/llvm/llvm-project/issues/58548#issuecomment-1287935336).
We should diagnose a const qualified member operator new but we fail to
do so and this leads to crash during debug info generation.
The fix is to diagnose this as ill-formed in the front-end.
Fixes: https://github.com/llvm/llvm-project/issues/79748
According to [temp.names] p5:
> The keyword template shall not appear immediately after a declarative nested-name-specifier.
[expr.prim.id.qual] p2 defines a declarative nested-name-specifier as follows:
> A nested-name-specifier is declarative if it is part of
> - a class-head-name,
> - an enum-head-name,
> - a qualified-id that is the id-expression of a declarator-id, or
> - a declarative nested-name-specifier.
Note: I believe this definition is defective as it doesn't include _nested-name-specifiers_ appearing in _elaborated-type-specifiers_ that declare partial/explicit specializations and explicit instantiations. See my post to the core reflector. Minus a few bugs that are addressed by this PR, this is how we implement it.
This means that declarations like:
```
template<typename>
struct A
{
template<typename>
struct B
{
void f();
};
};
template<typename T>
template<typename U>
void A<T>::template B<U>::f() { } // error: 'template' cannot be used after a declarative nested name specifier
```
are ill-formed. This PR add diagnostics for such declarations. The name of the diagnostic group is `template-in-declaration-name`.
Regarding the aforementioned "few bugs that are addressed by this PR" in order to correctly implement this:
- `CheckClassTemplate` did not call `diagnoseQualifiedDeclaration` when the semantic context was dependent. This allowed for constructs like:
```
struct A
{
template<typename T>
struct B
{
template<typename U>
struct C;
};
};
template<typename T>
template<typename U>
struct decltype(A())::B<T>::C { };
```
- `ActOnClassTemplateSpecialization` did not call `diagnoseQualifiedDeclaration` at all, allowing for qualified partial/explicit specializations at class scope and other related nonsense
- `TreeTransform::TransformNestedNameSpecifierLoc` would rebuild a `NestedNameSpecifier::TypeSpecWithTemplate` as a `NestedNameSpecifier::TypeSpec`
- `TemplateSpecializationTypeLoc::initializeLocal` would set the `template` keyword `SourceLocation` to the provided `Loc` parameter, which would result in a `TemplateSpecializationTypeLoc` obtained via `ASTContext::getTrivialTypeSourceInfo` being displayed as always having a `template` prefix (since the presence of the keyword is not stored anywhere else).
Consider the following:
```
namespace N0 {
namespace N1 {
template<typename T>
int x1 = 0;
}
using namespace N1;
}
template<>
int N0::x1<int>;
```
According to [dcl.meaning.general] p3.3:
> - If the _declarator_ declares an explicit instantiation or a partial
or explicit specialization, the _declarator_ does not bind a name. If it
declares a class member, the terminal name of the _declarator-id_ is not
looked up; otherwise, **only those lookup results that are nominable in
`S` are considered when identifying any function template specialization
being declared**.
In particular, the requirement for lookup results to be nominal in the
lookup context of the terminal name of the _declarator-id_ only applies
to function template specializations -- not variable template
specializations. We currently reject the above declaration, but we do
(correctly) accept it if the using-directive is replaced with a `using`
declaration naming `N0::N1::x1`. This patch makes it so the above
specialization is (correctly) accepted.
When a function F has ZA and ZT0 state, calls another function G that
only shares ZT0 state with its caller, F will have to save ZA before
the call to G, and restore it afterwards (rather than setting up a
lazy-sve).
This is not yet implemented in LLVM and does not result in a
compile-time error either. So instead of silently generating incorrect
code, it's better to emit an error saying this is not yet implemented.
Move the diagnostic so it fires only when doing an OpenMP capture, not
for non-OpenMP captures. This allows non-OpenMP code to work when using
OpenMP elsewhere, such as the code reported in
https://github.com/llvm/llvm-project/issues/66999.
This patch removes on-stack `TemplateArgumentList`'s. They were primary used
to pass an `ArrayRef<TemplateArgument>` to
`Sema::getTemplateInstantiationArgs`, which had a `const
TemplateArgumentList*` parameter for the innermost template argument
list. Changing this parameter to an
`std::optional<ArrayRef<TemplateArgument>>` eliminates the need for
on-stack `TemplateArgumentList`'s, which in turn eliminates the need for
`TemplateArgumentList` to store a pointer to its template argument
storage (which is redundant in almost all cases, as it is an AST
allocated type).
…lt align crash (#78400)"
This reverts commit 7b3389980ddbd84f72ccc4776889c67519cc2c14.
A regression was discovered here:
https://github.com/llvm/llvm-project/pull/78400
and the author requested a revert to give time to review.
This is a support for " #pragma omp atomic compare weak". It has Parser
& AST support for now.
---------
Authored-by: Sunil Kuravinakop <kuravina@pe28vega.us.cray.com>
This re-applies 30155fc0 with a fix for clangd.
### Description
clang don't evaluate the object argument of `static operator()` and
`static operator[]` currently, for example:
```cpp
#include <iostream>
struct Foo {
static int operator()(int x, int y) {
std::cout << "Foo::operator()" << std::endl;
return x + y;
}
static int operator[](int x, int y) {
std::cout << "Foo::operator[]" << std::endl;
return x + y;
}
};
Foo getFoo() {
std::cout << "getFoo()" << std::endl;
return {};
}
int main() {
std::cout << getFoo()(1, 2) << std::endl;
std::cout << getFoo()[1, 2] << std::endl;
}
```
`getFoo()` is expected to be called, but clang don't call it currently
(17.0.6). This PR fixes this issue.
Fixes#67976, reland #68485.
### Walkthrough
- **clang/lib/Sema/SemaOverload.cpp**
- **`Sema::CreateOverloadedArraySubscriptExpr` &
`Sema::BuildCallToObjectOfClassType`**
Previously clang generate `CallExpr` for static operators, ignoring the
object argument. In this PR `CXXOperatorCallExpr` is generated for
static operators instead, with the object argument as the first
argument.
- **`TryObjectArgumentInitialization`**
`const` / `volatile` objects are allowed for static methods, so that we
can call static operators on them.
- **clang/lib/CodeGen/CGExpr.cpp**
- **`CodeGenFunction::EmitCall`**
CodeGen changes for `CXXOperatorCallExpr` with static operators: emit
and ignore the object argument first, then emit the operator call.
- **clang/lib/AST/ExprConstant.cpp**
- **`ExprEvaluatorBase::handleCallExpr`**
Evaluation of static operators in constexpr also need some small changes
to work, so that the arguments won't be out of position.
- **clang/lib/Sema/SemaChecking.cpp**
- **`Sema::CheckFunctionCall`**
Code for argument checking also need to be modify, or it will fail the
test `clang/test/SemaCXX/overloaded-operator-decl.cpp`.
- **clang-tools-extra/clangd/InlayHints.cpp**
- **`InlayHintVisitor::VisitCallExpr`**
Now that the `CXXOperatorCallExpr` for static operators also have object
argument, we should also take care of this situation in clangd.
### Tests
- **Added:**
- **clang/test/AST/ast-dump-static-operators.cpp**
Verify the AST generated for static operators.
- **clang/test/SemaCXX/cxx2b-static-operator.cpp**
Static operators should be able to be called on const / volatile
objects.
- **Modified:**
- **clang/test/CodeGenCXX/cxx2b-static-call-operator.cpp**
- **clang/test/CodeGenCXX/cxx2b-static-subscript-operator.cpp**
Matching the new CodeGen.
### Documentation
- **clang/docs/ReleaseNotes.rst**
Update release notes.
---------
Co-authored-by: Shafik Yaghmour <shafik@users.noreply.github.com>
Co-authored-by: cor3ntin <corentinjabot@gmail.com>
Co-authored-by: Aaron Ballman <aaron@aaronballman.com>
- Sema::isSimpleTypeSpecifier return true for _Bool in c99 (currently
returns false for _Bool, regardless of C dialect). (Fixes#72203)
- replace the logic with a check for simple types and a proper check for
a valid keyword in the appropriate dialect
Co-authored-by: Carl Peto <CPeto@becrypt.com>
Fixes issue #79435
Checks for implicit conversion into boolean was previously triggered by
`CheckBoolLikeConversion` for C.
When `bool` as a keyword was introduced in C23,
`CheckBoolLikeConversion` would no longer trigger when using `-std=c23`,
but since logical operators and conditional statements still operate on
scalar values, the checks for implicit conversion into bool were never
triggered.
This fix changes `CheckBoolLikeConversion` to not return early for C23,
even though it has support for bools.
### Description
clang don't evaluate the object argument of `static operator()` and
`static operator[]` currently, for example:
```cpp
#include <iostream>
struct Foo {
static int operator()(int x, int y) {
std::cout << "Foo::operator()" << std::endl;
return x + y;
}
static int operator[](int x, int y) {
std::cout << "Foo::operator[]" << std::endl;
return x + y;
}
};
Foo getFoo() {
std::cout << "getFoo()" << std::endl;
return {};
}
int main() {
std::cout << getFoo()(1, 2) << std::endl;
std::cout << getFoo()[1, 2] << std::endl;
}
```
`getFoo()` is expected to be called, but clang don't call it currently
(17.0.2). This PR fixes this issue.
Fixes#67976.
### Walkthrough
- **clang/lib/Sema/SemaOverload.cpp**
- **`Sema::CreateOverloadedArraySubscriptExpr` &
`Sema::BuildCallToObjectOfClassType`**
Previously clang generate `CallExpr` for static operators, ignoring the
object argument. In this PR `CXXOperatorCallExpr` is generated for
static operators instead, with the object argument as the first
argument.
- **`TryObjectArgumentInitialization`**
`const` / `volatile` objects are allowed for static methods, so that we
can call static operators on them.
- **clang/lib/CodeGen/CGExpr.cpp**
- **`CodeGenFunction::EmitCall`**
CodeGen changes for `CXXOperatorCallExpr` with static operators: emit
and ignore the object argument first, then emit the operator call.
- **clang/lib/AST/ExprConstant.cpp**
- **`ExprEvaluatorBase::handleCallExpr`**
Evaluation of static operators in constexpr also need some small changes
to work, so that the arguments won't be out of position.
- **clang/lib/Sema/SemaChecking.cpp**
- **`Sema::CheckFunctionCall`**
Code for argument checking also need to be modify, or it will fail the
test `clang/test/SemaCXX/overloaded-operator-decl.cpp`.
### Tests
- **Added:**
- **clang/test/AST/ast-dump-static-operators.cpp**
Verify the AST generated for static operators.
- **clang/test/SemaCXX/cxx2b-static-operator.cpp**
Static operators should be able to be called on const / volatile
objects.
- **Modified:**
- **clang/test/CodeGenCXX/cxx2b-static-call-operator.cpp**
- **clang/test/CodeGenCXX/cxx2b-static-subscript-operator.cpp**
Matching the new CodeGen.
### Documentation
- **clang/docs/ReleaseNotes.rst**
Update release notes.
---------
Co-authored-by: Shafik Yaghmour <shafik@users.noreply.github.com>
Co-authored-by: cor3ntin <corentinjabot@gmail.com>
Co-authored-by: Aaron Ballman <aaron@aaronballman.com>
According to [[dcl.type.elab]
p2](http://eel.is/c++draft/dcl.type.elab#2):
> If an
[elaborated-type-specifier](http://eel.is/c++draft/dcl.type.elab#nt:elaborated-type-specifier)
is the sole constituent of a declaration, the declaration is ill-formed
unless it is an explicit specialization, an explicit instantiation or it
has one of the following forms [...]
Consider the following:
```cpp
template<typename T>
struct A
{
template<typename U>
struct B;
};
template<>
template<typename U>
struct A<int>::B; // #1
```
The _elaborated-type-specifier_ at `#1` declares an explicit
specialization (which is itself a template). We currently (incorrectly)
reject this, and this PR fixes that.
I moved the point at which _elaborated-type-specifiers_ with
_nested-name-specifiers_ are diagnosed from `ParsedFreeStandingDeclSpec`
to `ActOnTag` for two reasons: `ActOnTag` isn't called for explicit
instantiations and partial/explicit specializations, and because it's
where we determine if a member specialization is being declared.
With respect to diagnostics, I am currently issuing the diagnostic
without marking the declaration as invalid or returning early, which
results in more diagnostics that I think is necessary. I would like
feedback regarding what the "correct" behavior should be here.
`OpaqueValueExpr` doesn't necessarily contain a source expression.
Particularly, after #78041, it is used to carry the type and the value
kind of a non-type template argument of floating-point type or referring
to a subobject (those are so called `StructuralValue` arguments).
This fixes#79575.
This is a follow-up for the comparison of constraints on out-of-line
function template definitions. We require the instantiation of a
ParmVarDecl while transforming the expression if that Decl gets
referenced by a DeclRefExpr. However, we're not actually performing the
class or function template instantiation at the time of such comparison.
Therefore, let's map these parameters to themselves so that they get
preserved after the substitution.
Fixes https://github.com/llvm/llvm-project/issues/74447.
In Sema in `BuildReturnStmt(...)` when we try to determine is the type
is move eligible or copy elidable we don't currently check of the init
of the `VarDecl` contain errors or not. This can lead to a crash since
we may send a type that is not complete into `getTypeInfo(...)` which
does not allow this.
This fixes: https://github.com/llvm/llvm-project/issues/63244https://github.com/llvm/llvm-project/issues/79745
When this option is passed to clang, external (and/or weak) symbols
are not assumed to have the minimum ABI alignment normally required.
Symbols defined locally that are not weak are however still given the
minimum alignment.
This is implemented by passing a new parameter to getMinGlobalAlign()
named HasNonWeakDef that is used to return the right alignment value.
This is needed when external symbols created from a linker script may
not get the ABI minimum alignment and must therefore be treated as
unaligned by the compiler.
This pull request would solve
https://github.com/llvm/llvm-project/issues/78449 .
There is also a discussion about this on stackoverflow:
https://stackoverflow.com/questions/77832658/stdtype-identity-to-support-several-variadic-argument-lists
.
The following program is well formed:
```cpp
#include <type_traits>
template <typename... T>
struct args_tag
{
using type = std::common_type_t<T...>;
};
template <typename... T>
void bar(args_tag<T...>, std::type_identity_t<T>..., int, std::type_identity_t<T>...) {}
// example
int main() {
bar(args_tag<int, int>{}, 4, 8, 15, 16, 23);
}
```
but Clang rejects it, while GCC and MSVC doesn't. The reason for this is
that, in `Sema::DeduceTemplateArguments` we are not prepared for this
case.
# Substitution/deduction of parameter packs
The logic that handles substitution when we have explicit template
arguments (`SubstituteExplicitTemplateArguments`) does not work here,
since the types of the pack are not pushed to `ParamTypes` before the
loop starts that does the deduction.
The other "candidate" that may could have handle this case would be the
loop that does the deduction for trailing packs, but we are not dealing
with trailing packs here.
# Solution proposed in this PR
The solution proposed in this PR works similar to the trailing pack
deduction. The main difference here is the end of the deduction cycle.
When a non-trailing template pack argument is found, whose type is not
explicitly specified and the next type is not a pack type, the length of
the previously deduced pack is retrieved (let that length be `s`). After
that the next `s` arguments are processed in the same way as in the case
of non trailing packs.
# Another possible solution
There is another possible approach that would be less efficient. In the
loop when we get to an element of `ParamTypes` that is a pack and could
be substituted because the type is deduced from a previous argument,
then `s` number of arg types would be inserted before the current
element of `ParamTypes` type. Then we would "cancel" the processing of
the current element, first process the previously inserted elements and
the after that re-process the current element.
Basically we would do what `SubstituteExplicitTemplateArguments` does
but during deduction.
# Adjusted test cases
In
`clang/test/CXX/temp/temp.fct.spec/temp.deduct/temp.deduct.call/p1-0x.cpp`
there is a test case named `test_pack_not_at_end` that should work, but
still does not. This test case is relevant because the note for the
error message has changed.
This is what the test case looks like currently:
```cpp
template<typename ...Types>
void pack_not_at_end(tuple<Types...>, Types... values, int); // expected-note {{<int *, double *> vs. <int, int>}}
void test_pack_not_at_end(tuple<int*, double*> t2) {
pack_not_at_end(t2, 0, 0, 0); // expected-error {{no match}}
// FIXME: Should the "original argument type must match deduced parameter
// type" rule apply here?
pack_not_at_end<int*, double*>(t2, 0, 0, 0); // ok
}
```
The previous note said (before my changes):
```
deduced conflicting types for parameter 'Types' (<int *, double *> vs. <>)
````
The current note says (after my changesand also clang 14 would say this
if the pack was not trailing):
```
deduced conflicting types for parameter 'Types' (<int *, double *> vs. <int, int>)
```
GCC says:
```
error: no matching function for call to ‘pack_not_at_end(std::tuple<int*, double*>&, int, int, int)’
70 | pack_not_at_end(t2, 0, 0, 9); // expected-error {{no match}}
````
---------
Co-authored-by: cor3ntin <corentinjabot@gmail.com>
Co-authored-by: Erich Keane <ekeane@nvidia.com>
Implements https://isocpp.org/files/papers/P2662R3.pdf
The feature is exposed as an extension in older language modes.
Mangling is not yet supported and that is something we will have to do before release.
We preserve the trailing requires-expression during the lambda
expression transformation. In order to get those referenced parameters
inside a requires-expression properly resolved to the instantiated
decls, we intended to inject these 'original' `ParmVarDecls` to the
current instantiaion scope, at `Sema::SetupConstraintScope`.
The previous approach seems to overlook nested instantiation chains,
leading to the crash within a nested lambda followed by a requires
clause.
This fixes https://github.com/llvm/llvm-project/issues/73418.
Constructing `std::span` objects with the two parameter constructors
could introduce mismatched bounds information, which defeats the
purpose of using `std::span`. Therefore, we warn every use of such
constructors.
rdar://115817781
Make __builtin_cpu_{init|supports|is} target independent and provide an
opt-in query for targets that want to support it. Each target is still
responsible for their specific lowering/code-gen. Also provide code-gen
for PowerPC.
I originally proposed this in https://reviews.llvm.org/D152914 and this
addresses the comments I received there.
---------
Co-authored-by: Nemanja Ivanovic <nemanjaivanovic@nemanjas-air.kpn>
Co-authored-by: Nemanja Ivanovic <nemanja@synopsys.com>
Try to fix [issue](https://github.com/llvm/llvm-project/issues/68490)
and some extented problem. Root cause of current issue is that error
handling in instantiation of function parameter with default
initialization on sizeof or align expression. When instance an
out-of-line template member function, depth of `TemplateTypeParmDecl` in
default initialization doesn't change while depth of other template
parameter does and this will lead to some template parameter
uninstanced. Also, sometime it will leader to wrong instantiation when
it uses the template parameter of class.
Fix it by add template args of context when it's out-of-line. This will
make `MultiLevelTemplateArgumentList::getNumLevels` matching the depth
of template parameter. Testcase with some `static_assert` demonstrates
the template parameter has been instanced correctly.
Co-authored-by: huqizhi <836744285@qq.com>
Try to fix [issue](https://github.com/llvm/llvm-project/issues/73619)
1. During transforming `FunctionProtoType`, if `ThisContext` is
`nullptr` and `CurrentContext` is `ClassTemplateSpecializationDecl`,
Constructor of `CXXThisScopeRAII` and `Sema::getCurrentThisType` won't
set `CXXThisTypeOverride` of Sema. This will lead to building `this` in
`RebuildCXXThisExpr` with a invalid type(NULL type) and cause crash.
2. During transforming attribute type, if `modifiedType` of attribute
type is changed, `EquivalentType` need to be transformed. If
`EquivalentType` is `FunctionProtoType`, its `ParamVarDecl` will not be
copyed(but parameter num does) and will not be instanced in
`TransformFunctionTypeParams` since `ParamVarDecl` is `nullptr`. This
will lead to crash in `findInstantiationOf`(can't find the instance of
`ParamVarDecl`).
This patch tries to fix these issues above.
1. If `CurrentContext` is `ClassTemplateSpecializationDecl`, Use it.
2. Use `EquivalentTypeLoc` instead of `EquivalentType` since it has
parameter info. But, if use current `TypeLocBuilder`, it will crash in
`TypeLocBuilder::push` since `LastType` is mismatch. Use an auxiliary
`TypeLocBuilder` instead and get transformed `EquivalentType`.
Co-authored-by: huqizhi <836744285@qq.com>
This patch optimize:
1. Reduce string size of RVVIntrinsicDef.
2. Reduce the type size of the index of intrinsics.
I use valgrind --tool=massif to analyze a simple program:
```
#include <riscv_vector.h>
vint32m1_t test(vint32m1_t v1, vint32m1_t v2, size_t vl) {
return __riscv_vadd(v1, v2, vl);
}
```
and before optimization, the peak memory usage is 15.68MB,
after optimization, the peak memory usage is 13.69MB.
Test updated to expect i8 gep.
Original message:
This adopts a similar behavior to AArch64 SVE, where bool vectors are
represented as a vector of chars with 1/8 the number of elements. This
ensures the vector always occupies a power of 2 number of bytes.
A consequence of this is that vbool64_t, vbool32_t, and vool16_t can
only be used with a vector length that guarantees at least 8 bits.
This adopts a similar behavior to AArch64 SVE, where bool vectors are
represented as a vector of chars with 1/8 the number of elements. This
ensures the vector always occupies a power of 2 number of bytes.
A consequence of this is that vbool64_t, vbool32_t, and vool16_t can
only be used with a vector length that guarantees at least 8 bits.
This patch builds on top of #76971 and implements support for:
* __arm_new("zt0")
* __arm_in("zt0")
* __arm_out("zt0")
* __arm_inout("zt0")
* __arm_preserves("zt0")
The patch fixes the crash introduced by the DataInvocation warning
gadget designed to warn against unsafe invocations of span::data method.
It also now considers the invocation of span::data method inside
parenthesis.
Radar: 121223051
---------
Co-authored-by: MalavikaSamak <malavika2@apple.com>
[Sema] Add `-fvisibility-global-new-delete=` option (#75364)
By default the implicitly declared replaceable global new and delete
operators are given a default visibility attribute. Previous work, see:
https://reviews.llvm.org/D53787, added
`-fvisibility-global-new-delete-hidden` to change this to a hidden
visibility attribute.
This change adds `-fvisibility-global-new-delete=` which controls
whether (or not) to add an implicit visibility attribute to the implicit
declarations for these functions, and what visibility that attribute
will specify. The option takes 4 values: `force-hidden`,
`force-protected`, `force-default` and `source`. Option values
`force-hidden`, `force-protected` and `force-default` assign hidden,
protected, and default visibilities respectively; the use of the term
force in the value names is designed to imply to a user that the semantics
of this option differ significantly from `-fvisibility=`. An option
value of `source` implies that no implicit attribute is added; without
the attribute the replaceable global new and delete operators behave
normally (like other functions) with respect to visibility attributes,
pragmas and options.
The motivation for the `source` value is to facilitate users who intend
to replace these functions either for a single linkage unit or a limited
set of linkage units. `-fvisibility-global-new-delete=source` can be
applied globally to the compilations in a build where the existing
`-fvisibility-global-new-delete-hidden` cannot, as it conflicts with a
common pattern where these functions are dynamically imported.
The existing `-fvisibility-global-new-delete-hidden` is now a deprecated
spelling of `-fvisibility-global-new-delete=force-hidden`
A release note has been added for these changes.
`-fvisibility-global-new-delete=source` will be set by default for PS5.
PS5 users that want the normal toolchain behaviour will be able to
supply `-fvisibility-global-new-delete=force-default`.
