We build up a `CXXFoldExpr` for immediately declared constraints as per
C++20 [temp.param]/4. This is done by
`formImmediatelyDeclaredConstraint` where an `EllipsisLoc` is essential
to determine whether this is a pack.
On the other hand, when attempting to instantiate a class template,
member templates might not be instantiated immediately, so we leave them
intact. For function templates with NTTPs, we reattach constraints if
possible so that they can be evaluated later. To properly form that, we
attempted to extract an ellipsis location if the param per se was a
parameter pack. Unfortunately, for the following NTTP case, we seemingly
failed to handle:
```cpp
template <Constraint auto... Pack>
void member();
```
The NTTPD Pack is neither an `ExpandedParameterPack` nor a
`PackExpansion` (its type does not expand anything). As a result, we end
up losing track of the constraints on packs, although we have them
inside the associated `CXXFoldExpr`.
This patch fixes that by extracting the ellipsis location out of the
previous constraint expression. Closes
https://github.com/llvm/llvm-project/issues/63837.
Despite CWG2497 not being resolved, it is reasonable to expect the
following code to compile (and which is supported by other compilers)
```cpp
template<typename T> constexpr T f();
constexpr int g() { return f<int>(); } // #1
template<typename T> constexpr T f() { return 123; }
int k[g()];
// #2
```
To that end, we eagerly instantiate all referenced specializations of
constexpr functions when they are defined.
We maintain a map of (pattern, [instantiations]) independent of
`PendingInstantiations` to avoid having to iterate that list after each
function definition.
We should apply the same logic to constexpr variables, but I wanted to
keep the PR small.
Fixes#73232
This change implements parsing for HLSL's parameter modifier keywords
`in`, `out` and `inout`. Because HLSL doesn't support references or
pointers, these keywords are used to allow parameters to be passed in
and out of functions.
This change only implements the parsing and AST support. In the HLSL
ASTs we represent `out` and `inout` parameters as references, and we
implement the semantics of by-value passing during IR generation.
In HLSL parameters marked `out` and `inout` are ambiguous in function
declarations, and `in`, `out` and `inout` may be ambiguous at call
sites.
This means a function may be defined as `fn(in T)` and `fn(inout T)` or
`fn(out T)`, but not `fn(inout T)` and `fn(out T)`. If a funciton `fn`
is declared with `in` and `inout` or `out` arguments, the call will be
ambiguous the same as a C++ call would be ambiguous given declarations
`fn(T)` and `fn(T&)`.
Fixes#59849
This change aims to fix
https://github.com/llvm/llvm-project/issues/70375
It appears to me that the logic here should be handling specializations
in general, not just partial specialization. It also seems that both the
comment before the block and the `isInstantiationOf(ClassTemplate,
SpecTemplate)` below agree with my judgement.
The issue might just be a mistake that someone mistaken specialization
as a special case of partial specializations, while it's actually the
other way around.
Needs some experts to comment here if this is the right fix.
The code that caused clang ICE is added as a test case.
Modifications:
- Skip the instantiation of the explicit-specifier during Decl
substitution if we are deducing template arguments and the
explicit-specifier is value dependent.
- Instantiate the explicit-specifier after the constraint checking
completes.
- Make `instantiateExplicitSpecifier` a member function in order to
instantiate the explicit-specifier in different stages.
This PR doesn’t defer the instantiation of the explicit specifier for
deduction guides, because I’m not familiar with deduction guides yet.
I’ll dig into it after this PR.
According to my local test, GCC 13 tuple works with this PR.
Fixes#59827.
---------
Co-authored-by: Erich Keane <ekeane@nvidia.com>
This patch moves `OMPDeclareReductionDecl::InitKind` to DeclBase.h, so that it's complete at the point where corresponding bit-field is declared. This patch also converts it to scoped enum named `OMPDeclareReductionInitKind`
Out of line class template declaration specializations aren't created at
the time they have their template arguments checked, so we previously
weren't doing any amount of work to substitute the constraints before
comparison. This resulted in the out of line definition's difference in
'depth' causing the constraints to compare differently.
This patch corrects that. Additionally, it handles ClassTemplateDecl
when collecting template arguments.
Fixes: #61763
This removes the `ClassScopeFunctionSpecializationDecl` `Decl` node, and
instead uses `DependentFunctionTemplateSpecializationInfo` to handle
such declarations. `DependentFunctionTemplateSpecializationInfo` is also
changed to store a `const ASTTemplateArgumentListInfo*` to be more in
line with `FunctionTemplateSpecializationInfo`.
This also changes `FunctionDecl::isFunctionTemplateSpecialization` to
return `true` for dependent specializations, and
`FunctionDecl::getTemplateSpecializationKind`/`FunctionDecl::getTemplateSpecializationKindForInstantiation`
to return `TSK_ExplicitSpecialization` for non-friend dependent
specializations (the same behavior as dependent class scope
`ClassTemplateSepcializationDecl` & `VarTemplateSepcializationDecl`).
If there are two guides, one of them generated from a non-templated
constructor
and the other from a templated constructor, then the standard gives
priority to
the first. Clang detected ambiguity before, now the correct guide is
chosen.
The correct behavior is described in this paper:
http://wg21.link/P0620R0
Example for the bug: http://godbolt.org/z/ee3e9qG78
As an unrelated minor change, fix the issue
https://github.com/llvm/llvm-project/issues/64020,
which could've led to incorrect behavior if further development inserted
code after a call to
`isAddressSpaceSubsetOf()`, which specified the two parameters in the
wrong order.
---------
Co-authored-by: hobois <horvath.botond.istvan@gmial.com>
Instantiating a lambda at a scope different from where it is defined
will paralyze clang if the trailing require clause refers to local
variables. This patch fixes this by re-adding the local variables to
`LocalInstantiationScope`.
Fixes#64462
This reverts commit 491b2810fb7fe5f080fa9c4f5945ed0a6909dc92.
This change broke valid code and generated incorrect diagnostics, see
https://reviews.llvm.org/D155064
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
This change corrects some cases where the source location for an
instantiated specialization of a function template or a member function
of a class template was assigned the location of a non-defining
declaration rather than the location of the definition the
specialization was instantiated from.
Fixes https://github.com/llvm/llvm-project/issues/26057
Reviewed By: cor3ntin
Differential Revision: https://reviews.llvm.org/D64087
Like concepts checking, a trailing return type of a lambda
in a dependent context may refer to captures in which case
they may need to be rebuilt, so the map of local decl
should include captures.
This patch reveal a pre-existing issue.
`this` is always recomputed by TreeTransform.
`*this` (like all captures) only become `const`
after the parameter list.
However, if try to recompute the value of `this` (in a parameter)
during template instantiation while determining the type of the call operator,
we will determine it to be const (unless the lambda is mutable).
There is no good way to know at that point that we are in a parameter
or not, the easiest/best solution is to transform the type of this.
Note that doing so break a handful of HLSL tests.
So this is a prototype at this point.
Fixes#65067Fixes#63675
Reviewed By: erichkeane
Differential Revision: https://reviews.llvm.org/D159126
Like concepts checking, a trailing return type of a lambda
in a dependent context may refer to captures in which case
they may need to be rebuilt, so the map of local decl
should include captures.
This patch reveal a pre-existing issue.
`this` is always recomputed by TreeTransform.
`*this` (like all captures) only become `const`
after the parameter list.
However, if try to recompute the value of `this` (in a parameter)
during template instantiation while determining the type of the call operator,
we will determine it to be const (unless the lambda is mutable).
There is no good way to know at that point that we are in a parameter
or not, the easiest/best solution is to transform the type of this.
Note that doing so break a handful of HLSL tests.
So this is a prototype at this point.
Fixes#65067Fixes#63675
Reviewed By: erichkeane
Differential Revision: https://reviews.llvm.org/D159126
AST nodes that may depend on FP options keep them as a difference
relative to the options outside the AST node. At the moment of
instantiation the FP options may be different from the default values,
defined by command-line option. In such case FP attributes would have
unexpected values. For example, the code:
template <class C> void func_01(int last, C) {
func_01(last, int());
}
void func_02() { func_01(0, 1); }
#pragma STDC FENV_ACCESS ON
caused compiler crash, because template instantiation takes place at the
end of translation unit, where pragma STDC FENV_ACCESS is in effect. As
a result, code in the template instantiation would use constrained
intrinsics while the function does not have StrictFP attribute.
To solve this problem, FP attributes in Sema must be set to default
values, defined by command line options.
This change resolves https://github.com/llvm/llvm-project/issues/63542.
Differential Revision: https://reviews.llvm.org/D154359
This diff switches the approach to comparison of constraint expressions
to the new one based on template args substitution.
It continues the effort to fix our handling of out-of-line definitions
of constrained templates.
This is a recommit of 3a54022934.
Differential revision: https://reviews.llvm.org/D146178
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
This diff switches the approach to comparison of constraint expressions
to the new one based on template args substitution.
It continues the effort to fix our handling of out-of-line definitions
of constrained templates.
This is a recommit of e3b1083e00.
Differential revision: https://reviews.llvm.org/D146178
This reverts commit e3b1083e00e62f5d157d15cb8c63a1c3dfdf12e2.
This was reverted because it breaks a number of libstdc++ examples, AND
required a workaround that causes hiding of legitimate bugs.
This diff switches the approach to comparison of constraint expressions
to the new one based on template args substitution.
It continues the effort to fix our handling of out-of-line definitions
of constrained templates.
This is a recommit of 60bee9ff5445.
Differential revision: https://reviews.llvm.org/D146178
This temporarily reverts commit
60bee9ff544541e83ffbd4be31923d0e8b644690.
The diff will be recommitted once the newly discovered
regressions are fixed.
PR D135370 implemented a performance improvement but it restricted the filtering
of declaration from inline namespace too much. In particular it did not filter
for the function template case.
This led to a regression and this PR removes that check.
This fixes: https://github.com/llvm/llvm-project/issues/61851
Differential Revision: https://reviews.llvm.org/D147762
This diff switches the approach to comparison of constraint expressions
to the new one based on template args substitution.
It continues the effort to fix our handling of out-of-line definitions
of constrained templates.
The associated GitHub issue: https://github.com/llvm/llvm-project/issues/61414
Test plan:
1/ ninja check-all
2/ bootstrapped Clang passes tests
Differential revision: https://reviews.llvm.org/D146178
Seemingly we never tested this, but the constraint on a NTTP was being
swtiched to the 'instantiated' version, but constraints need to be
relative to the 'top level', so this was causing us to not be able to
check the constraint on final use.
This patch corrects the issue by making the constraint created with the
un-instantiated version in the case of dependent constraint attachment.
Fixes: #61777
If a template function contained a pragma that made it strictfp, code
generation for such function crashed, because the instantiation did not
have strictfp attribute. As a solution this attribute is copied from the
template to instantiation.
Differential Revision: https://reviews.llvm.org/D143919
