**Summary**
This patch adds a `IsDefaulted` field to `clang::TemplateArgument`.
To prevent memory footprint increase we still 1 bit from `ArgKind`.
**Changes**
1. `getIsDefaulted`/`setIsDefaulted` to allow clients to communicate
an argument's defaulted-ness to the TypePrinter
2. The `TemplateArgument` properties description had to be changed
to make sure we correctly mark the defaulted-ness of arguments
that came from a deserialized AST (caught by the HLSL test-suite)
3. The `TemplateArgument` constructors now accept a `IsDefaulted`
parameter to simplify construction from the tablegen description.
Though if people don't want to clutter the constructors we can
instead call `setIsDefaulted` from tablegen
4. When `clang::Sema` checks the template arguments against template
parameters we now call `setIsDefaulted`. This makes sure that
whenever a specialization decl gets constructed, the defaulted-ness
of the associated `TemplateArgument`s has already been deduced.
This preserves the immutability of `TemplateArgumentList`s
**Background**
In LLDB we construct ASTs from debug-info and hand it to clang
to perform actions such as printing/formatting a typenames.
Some debug formats, specifically DWARF, may only encode information
about class template instantiations, losing the structure of the generic
class definition. However, the `clang::TypePrinter` needs a properly
constructed `ClassTemplateDecl` with generic default argument decls
to be able to deduce whether a `ClassTemplateSpecializationDecl` was
instantiatiated with `TemplateArgument`s that correspond to the
defaults. LLDB does know whether a particular template argument was
defaulted, but can't currently tell clang about it.
This patch allows LLDB to set the defaulted-ness of a `TemplateArgument`
and thus benefit more from `clang::TypePrinter`.
See discussion in https://reviews.llvm.org/D140423
**Testing**
* Added unit-test
* LLDB/clang/llvm test-suite passes
Differential Revision: https://reviews.llvm.org/D141826
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!
}
```
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
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
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
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>
This reverts commit b8064374b217db061213c561ec8f3376681ff9c8.
Based on the report here:
https://github.com/llvm/llvm-project/issues/59271
this produces a significant increase in memory use of the compiler and a
large compile-time regression. This patch reverts this so that we don't
branch for release with that issue.
This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated. The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.
This is part of an effort to migrate from llvm::Optional to
std::optional:
https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
More work for temp.friend p9, this fixes a previous bug where we didn't
properly consider a friend to depend on the enclosing template if it
only did so via an NTTP.
This makes use of the changes introduced in D134604, in order to
instantiate alias templates witn a final sugared substitution.
This comes at no additional relevant cost.
Since we don't track / unique them in specializations, we wouldn't be
able to resugar them later anyway.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D136565
This makes use of the changes introduced in D134604, in order to
instantiate non-type template parameters and default template arguments
with a final sugared substitution.
This comes at no additional relevant cost.
Since we don't track / unique them in specializations, we wouldn't be
able to resugar them later anyway.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D136564
This patch reverts
- commit d4b1964f0554046b1e64908e5c1cd701b25f4c9e
- commit 59f0827e2cf3755834620e7e0b6d946832440f80([clang] Instantiate alias templates with sugar)
As it makes clang fail to pass some code it used to compile.
See comments: https://reviews.llvm.org/D136564#3891065
template-template parameters. Although it effects whether a template can be
used as an argument for another template, the constraint seems not to
be checked, nor other major implementations (GCC, MSVC, et al.) check it.
Additionally, Part-A of the document seems to have been implemented.
So mark P0857R0 as completed.
Differential Revision: https://reviews.llvm.org/D134128
Since we don't unique specializations for concepts, we can just instantiate
them with the sugared template arguments, at negligible cost.
If we don't track their specializations, we can't resugar them later
anyway, and that would be more expensive than just instantiating them
sugared in the first place since it would require an additional pass.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D136566
This makes use of the changes introduced in D134604, in order to
instantiate alias templates witn a final sugared substitution.
This comes at no additional relevant cost.
Since we don't track / unique them in specializations, we wouldn't be
able to resugar them later anyway.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D136565
This makes use of the changes introduced in D134604, in order to
instantiate non-type template parameters and default template arguments
with a final sugared substitution.
This comes at no additional relevant cost.
Since we don't track / unique them in specializations, we wouldn't be
able to resugar them later anyway.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D136564
Implements the changes required to perform substitution with
non-canonical template arguments, and to 'finalize' them
by not placing 'Subst' nodes.
A finalized substitution means we won't resugar them later,
because these templates themselves were eagerly substituted
with the intended arguments at the point of use. We may still
resugar other templates used within those, though.
This patch does not actually implement any uses of this
functionality, those will be added in subsequent patches,
so expect no changes to existing tests.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D134604
Since these are much like template type aliases, where we don't
track a specialization for them and just substitute them eagerly,
we can't resugar them anyway, and there is no relevant cost in just
performing a finalizing sugared substitution.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D136563
Makes CheckTemplateArgumentList and the template deduction functions
produce a sugared converted argument list in addition to the canonical one.
This is mostly NFC except that we hook this up to a few diagnostics in
SemaOverload.
The infrastructure here will be used in subsequent patches
where we perform a finalized sugared substitution for entities
which we do not unique per specializations on canonical arguments,
and later on will be used for template specialization resugaring.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D133874
Since we don't unique specializations for concepts, we can just instantiate
them with the sugared template arguments, at negligible cost.
If we don't track their specializations, we can't resugar them later
anyway, and that would be more expensive than just instantiating them
sugared in the first place since it would require an additional pass.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D136566
This makes use of the changes introduced in D134604, in order to
instantiate alias templates witn a final sugared substitution.
This comes at no additional relevant cost.
Since we don't track / unique them in specializations, we wouldn't be
able to resugar them later anyway.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D136565
This makes use of the changes introduced in D134604, in order to
instantiate non-type template parameters and default template arguments
with a final sugared substitution.
This comes at no additional relevant cost.
Since we don't track / unique them in specializations, we wouldn't be
able to resugar them later anyway.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D136564
Implements the changes required to perform substitution with
non-canonical template arguments, and to 'finalize' them
by not placing 'Subst' nodes.
A finalized substitution means we won't resugar them later,
because these templates themselves were eagerly substituted
with the intended arguments at the point of use. We may still
resugar other templates used within those, though.
This patch does not actually implement any uses of this
functionality, those will be added in subsequent patches,
so expect no changes to existing tests.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D134604
Since these are much like template type aliases, where we don't
track a specialization for them and just substitute them eagerly,
we can't resugar them anyway, and there is no relevant cost in just
performing a finalizing sugared substitution.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D136563
Makes CheckTemplateArgumentList and the template deduction functions
produce a sugared converted argument list in addition to the canonical one.
This is mostly NFC except that we hook this up to a few diagnostics in
SemaOverload.
The infrastructure here will be used in subsequent patches
where we perform a finalized sugared substitution for entities
which we do not unique per specializations on canonical arguments,
and later on will be used for template specialization resugaring.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D133874
This reverts commit dc170433137aeda5e5276bd292cac12aa93fee7c.
Breaks building LLVM on mac when targeting macOS before 10.15, see
comments on https://reviews.llvm.org/D136533
Removes a bunch of obsolete methods in favor of a single one returning
an ArrayRef of TemplateArgument.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D136602
This reverts commit cecc9a92cfca71c1b6c2a35c5e302ab649496d11.
The problem ended up being how we were handling the lambda-context in
code generation: we were assuming any decl context here would be a
named-decl, but that isn't the case. Instead, we just replace it with
the concept's owning context.
Differential Revision: https://reviews.llvm.org/D136451
This reverts commit b876f6e2f28779211a829d7d4e841fe68885ae20.
Still getting build failures on PPC AIX that aren't obvious what is causing
them, so reverting while I try to figure this out.
