Commit Graph

2284 Commits

Author SHA1 Message Date
Kazu Hirata 8595f2e54d [Sema] Use std::nullopt instead of None (NFC)
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
2022-12-03 11:13:39 -08:00
Corentin Jabot 9221bedfd7 Revert "Implement CWG2631"
This reverts commit 26fa17ed29.
This reverts commit 4403c4f9e7.

There is still an ODR issue causing linker errors, investigating.
2022-11-30 16:03:05 +01:00
Corentin Jabot 26fa17ed29 Implement CWG2631
Implement https://cplusplus.github.io/CWG/issues/2631.html.

Immediate calls in default arguments and defaults members
are not evaluated.

Instead, we evaluate them when constructing a
`CXXDefaultArgExpr`/`BuildCXXDefaultInitExpr`.

The immediate calls are executed by doing a
transform on the initializing expression.

Note that lambdas are not considering subexpressions so
we do not need to transform them.

As a result of this patch, unused default member
initializers are not considered odr-used, and
errors about members binding to local variables
in an outer scope only surface at the point
where a constructor is defined.

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

Differential Revision: https://reviews.llvm.org/D136554
2022-11-30 11:25:01 +01:00
Roy Jacobson 3faf1f17a5 [Clang] Implement static operator[]
After accepted in Kona, update the code to accept static operator[] as well.

No big code changes: accept this operator as static in SemaDeclCXX, update AST call generation in SemaOverload and update feature macros + tests accordingly.

Reviewed By: cor3ntin, erichkeane, #clang-language-wg

Differential Revision: https://reviews.llvm.org/D138387
2022-11-29 12:39:52 +02:00
Erich Keane 07008a8df5 CWG2635: Disallow constrained structured bindings.
CWG2635 prohibits adding a constraint to a structured as a defect
report.  This patch implements that restriction.

Differential Revision: https://reviews.llvm.org/D138852
2022-11-28 14:41:14 -08:00
Nathan James 15e76eed0c
[clang] Add [is|set]Nested methods to NamespaceDecl
Adds support for NamespaceDecl to inform if its part of a nested namespace.
This flag only corresponds to the inner namespaces in a nested namespace declaration.
In this example:
namespace <X>::<Y>::<Z> {}
Only <Y> and <Z> will be classified as nested.

This flag isn't meant for assisting in building the AST, more for static analysis and refactorings.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D90568
2022-11-24 12:44:35 +00:00
Timm Bäder 051230359c [clang][NFC] Remove unused CastForMoving parameter
Nothing ever passes a third parameter to CastForMoving.
2022-11-16 10:02:52 +01:00
Rageking8 94738a5ac3 Fix duplicate word typos; NFC
This revision fixes typos where there are 2 consecutive words which are
duplicated. There should be no code changes in this revision (only
changes to comments and docs). Do let me know if there are any
undesirable changes in this revision. Thanks.
2022-11-08 07:21:23 -05:00
Timm Bäder 73ecff2333 [clang][Sema][NFC] Remove two nonsensical dyn_cast_or_null
The values used here are never null.
2022-11-08 12:47:41 +01:00
Grace Jennings 86674f66cc [HLSL] Added HLSL this as a reference
This change makes `this` a reference instead of a pointer in
HLSL. HLSL does not have the `->` operator, and accesses through `this`
are with the `.` syntax.

Tests were added and altered to make sure
the AST accurately reflects the types.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D135721
2022-11-07 13:50:08 -08:00
Corentin Jabot 35a870c30a Revert "Implement CWG2631"
This reverts commit 7acfe36294.
This reverts commit 5f87a892a7.
This reverts commit 6875ac6927.
2022-11-04 22:10:50 +01:00
Corentin Jabot 7acfe36294 Implement CWG2631
Implement https://cplusplus.github.io/CWG/issues/2631.html.

Immediate calls in default arguments and defaults members
are not evaluated.

Instead, we evaluate them when constructing a
`CXXDefaultArgExpr`/`BuildCXXDefaultInitExpr`.

The immediate calls are executed by doing a
transform on the initializing expression.

Note that lambdas are not considering subexpressions so
we do not need to transform them.

As a result of this patch, unused default member
initializers are not considered odr-used, and
errors about members binding to local variables
in an outer scope only surface at the point
where a constructor is defined.

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

Differential Revision: https://reviews.llvm.org/D136554
2022-11-04 14:46:38 +01:00
Corentin Jabot 722a0efe31 Revert "Implement CWG2631"
Breaks the build on some platforms.

This reverts commit bf1e235695.
2022-11-04 08:24:52 +01:00
Corentin Jabot bf1e235695 Implement CWG2631
Implement https://cplusplus.github.io/CWG/issues/2631.html.

Immediate calls in default arguments and defaults members
are not evaluated.

Instead, we evaluate them when constructing a
`CXXDefaultArgExpr`/`BuildCXXDefaultInitExpr`.

The immediate calls are executed by doing a
transform on the initializing expression.

Note that lambdas are not considering subexpressions so
we do not need to transform them.

As a result of this patch, unused default member
initializers are not considered odr-used, and
errors about members binding to local variables
in an outer scope only surface at the point
where a constructor is defined.

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

Differential Revision: https://reviews.llvm.org/D136554
2022-11-04 07:58:57 +01:00
Corentin Jabot 742970920b [Clang] Implement CWG2358 Explicit capture of value
Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D137172
2022-11-03 13:27:11 +01:00
Erich Keane 2cee266333 [Concepts] Correctly handle failure when checking concepts recursively
Based on discussion on the core reflector, it was made clear that a
concept that depends on itself should be a hard error, not a constraint
failure. This patch implements a stack of constraint-checks-in-progress
to make sure we quit, rather than hitting stack-exhaustion.

Note that we DO need to be careful to make sure we still check
constraints properly that are caused by a previous constraint, but not
derived from (such as when a check causes us to check special member
function generation), so we cannot use the existing logic to see if this
is being instantiated.

This fixes https://github.com/llvm/llvm-project/issues/44304 and
https://github.com/llvm/llvm-project/issues/50891.

Differential Revision: https://reviews.llvm.org/D136975
2022-11-01 12:18:58 -07:00
Matheus Izvekov 1acffe81ee
NFC: [clang] Template argument cleanups.
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
2022-10-25 00:29:56 +02:00
Erich Keane 4bcb85c638 Stop evaluating trailing requires clause after overload resolution
Reported as it showed up as a constriants failure after the deferred
instantiation patch, we were checking constraints TWICE after overload
resolution.  The first is during overload resolution, the second is when
diagnosing a use.

This patch modifies DiagnoseUseOfDecl to skip the trailing requires
clause check in some cases. First, of course, after choosing a candidate
after overload resolution.

The second is when evaluating a shadow using constructor, which had its
constraints checked when picking a constructor (as this is ALWAYS an
overload situation!).

Differential Revision: https://reviews.llvm.org/D135772
2022-10-18 06:08:10 -07:00
Aaron Ballman 3a31970ee2 [C2x] Implement support for nullptr and nullptr_t
This introduces support for nullptr and nullptr_t in C2x mode. The
proposal accepted by WG14 is:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3042.htm

Note, there are quite a few incompatibilities with the C++ feature in
some of the edge cases of this feature. Therefore, there are some FIXME
comments in tests for testing behavior that might change after WG14 has
resolved national body comments (a process we've not yet started). So
this implementation might change slightly depending on the resolution
of comments. This is called out explicitly in the release notes as
well.

Differential Revision: https://reviews.llvm.org/D135099
2022-10-14 10:06:02 -04:00
Sam McCall 2eaf6f973c [AST] Preserve more structure in UsingEnumDecl node.
- store NestedNameSpecifier & Loc for the qualifiers
  This information was entirely missing from the AST.
- expose the location information for qualifier/identifier/typedefs as typeloc
  This allows many traversals/astmatchers etc to handle these generically along
  with other references. The decl vs type split can help preserve typedef
  sugar when https://github.com/llvm/llvm-project/issues/57659 is resolved.
- fix the SourceRange of UsingEnumDecl to include 'using'.

Fixes https://github.com/clangd/clangd/issues/1283

Differential Revision: https://reviews.llvm.org/D134303
2022-10-12 19:54:51 +02:00
Utkarsh Saxena 38b9d313e6 [C++20][Clang] P2468R2 The Equality Operator You Are Looking For
Implement
https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/p2468r2.html.

Primarily we now accept
```
template<typename T> struct CRTPBase {
  bool operator==(const T&) const;
  bool operator!=(const T&) const;
};
struct CRTP : CRTPBase<CRTP> {};
bool cmp_crtp = CRTP() == CRTP();
bool cmp_crtp2 = CRTP() != CRTP();
```

Differential Revision: https://reviews.llvm.org/D134529
2022-10-06 13:21:34 +02:00
Kadir Cetinkaya adab08ecf2
[clang][Sema] Fix crash on invalid base destructor
LookupSpecialMember might fail, so changes the cast to cast_or_null.
Inside Sema, skip a particular base, similar to other cases, rather than
asserting on dtor showing up.

Other option would be to mark classes with invalid destructors as invalid, but
that seems like a lot more invasive and we do lose lots of diagnostics that
currently work on classes with broken members.

Differential Revision: https://reviews.llvm.org/D135254
2022-10-05 15:23:15 +02:00
Yuanfang Chen 5d69937b9f [Clang] make canonical AutoType constraints-free
As @mizvekov suggested in D134772. This works great for D128750 when
dealing with AutoType's.

Reviewed By: mizvekov, erichkeane

Differential Revision: https://reviews.llvm.org/D135088
2022-10-04 11:56:03 -07:00
Nathan James 1376c73927
[clang] Add fix-it note to defaulted-function-deleted warning
Adds a fix to the diagnostic of replacing the `= default` to `= delete`

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D134549
2022-10-04 19:38:10 +01:00
Roy Jacobson 6523814c4e [Clang] P1169R4: static operator()
Implements 'P1169R4: static operator()' from C++2b.

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

Differential Revision: https://reviews.llvm.org/D133659
2022-09-29 23:03:26 +03:00
Martin Sebor a181de452d [clang] handle extended integer constant expressions in _Static_assert (PR #57687)
Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D134311
2022-09-28 13:27:58 -06:00
Nathan Sidwell 3d2080683f [clang][DR2621] using enum NAME lookup fix
Although using-enum's grammar is 'using elaborated-enum-specifier',
the lookup for the enum is ordinary lookup (and not the tagged-type
lookup that normally occurs wth an tagged-type specifier).  Thus (a)
we can find typedefs and (b) do not find enum tags hidden by a non-tag
name (the struct stat thing).

This reimplements that part of using-enum handling, to address DR2621,
where clang's behaviour does not match std intent (and other
compilers).

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D134283
2022-09-28 08:50:27 -07:00
Haojian Wu 4f8d92f1d6 [clang] Fix the bogus diagnostic introduced by the newly-added UsingTemplate Kind.
Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D123808
2022-09-23 10:36:55 +02:00
Matheus Izvekov 989f76ce90
[clang] template / auto deduction deduces common sugar
After upgrading the type deduction machinery to retain type sugar in
D110216, we were left with a situation where there is no general
well behaved mechanism in Clang to unify the type sugar of multiple
deductions of the same type parameter.

So we ended up making an arbitrary choice: keep the sugar of the first
deduction, ignore subsequent ones.

In general, we already had this problem, but in a smaller scale.
The result of the conditional operator and many other binary ops
could benefit from such a mechanism.

This patch implements such a type sugar unification mechanism.

The basics:

This patch introduces a `getCommonSugaredType(QualType X, QualType Y)`
method to ASTContext which implements this functionality, and uses it
for unifying the results of type deduction and return type deduction.
This will return the most derived type sugar which occurs in both X and
Y.

Example:

Suppose we have these types:
```
using Animal = int;
using Cat = Animal;
using Dog = Animal;

using Tom = Cat;
using Spike = Dog;
using Tyke = Dog;
```
For `X = Tom, Y = Spike`, this will result in `Animal`.
For `X = Spike, Y = Tyke`, this will result in `Dog`.

How it works:

We take two types, X and Y, which we wish to unify as input.
These types must have the same (qualified or unqualified) canonical
type.

We dive down fast through top-level type sugar nodes, to the
underlying canonical node. If these canonical nodes differ, we
build a common one out of the two, unifying any sugar they had.
Note that this might involve a recursive call to unify any children
of those. We then return that canonical node, handling any qualifiers.

If they don't differ, we walk up the list of sugar type nodes we dived
through, finding the last identical pair, and returning that as the
result, again handling qualifiers.

Note that this patch will not unify sugar nodes if they are not
identical already. We will simply strip off top-level sugar nodes that
differ between X and Y. This sugar node unification will instead be
implemented in a subsequent patch.

This patch also implements a few users of this mechanism:
* Template argument deduction.
* Auto deduction, for functions returning auto / decltype(auto), with
  special handling for initializer_list as well.

Further users will be implemented in a subsequent patch.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D111283
2022-09-16 11:20:10 +02:00
Julius 49e7ef2c09 [Clang]: Diagnose deprecated copy operations also in MSVC compatibility mode
When running in MSVC compatibility mode, previously no deprecated copy
operation warnings (enabled by -Wdeprecated-copy) were raised. This
restriction was already in place when the deprecated copy warning was
first introduced.

This patch removes said restriction so that deprecated copy warnings, if
enabled, are also raised in MSVC compatibility mode. The reasoning here
being that these warnings are still useful when running in MSVC
compatibility mode and also have to be semi-explicitly enabled in the
first place (using -Wdeprecated-copy, -Wdeprecated or -Wextra).

Differential Revision: https://reviews.llvm.org/D133354
2022-09-14 19:48:08 +02:00
Alexander Kornienko 637da9de4c Revert "[clang] template / auto deduction deduces common sugar"
This reverts commit d200db3863, which causes a
clang crash. See https://reviews.llvm.org/D111283#3785755

Test case for convenience:
```
template <typename T>
using P = int T::*;

template <typename T, typename... A>
void j(P<T>, T, A...);

template <typename T>
void j(P<T>, T);

struct S {
  int b;
};
void g(P<S> k, S s) { j(k, s); }
```
2022-09-13 12:18:07 +02:00
Corentin Jabot 7eead180b9 [Clang] NFC: Make UnqualifiedId::Kind private for consistency.
Differential Revision: https://reviews.llvm.org/D133703
2022-09-12 19:14:06 +02:00
Matheus Izvekov d200db3863
[clang] template / auto deduction deduces common sugar
After upgrading the type deduction machinery to retain type sugar in
D110216, we were left with a situation where there is no general
well behaved mechanism in Clang to unify the type sugar of multiple
deductions of the same type parameter.

So we ended up making an arbitrary choice: keep the sugar of the first
deduction, ignore subsequent ones.

In general, we already had this problem, but in a smaller scale.
The result of the conditional operator and many other binary ops
could benefit from such a mechanism.

This patch implements such a type sugar unification mechanism.

The basics:

This patch introduces a `getCommonSugaredType(QualType X, QualType Y)`
method to ASTContext which implements this functionality, and uses it
for unifying the results of type deduction and return type deduction.
This will return the most derived type sugar which occurs in both X and
Y.

Example:

Suppose we have these types:
```
using Animal = int;
using Cat = Animal;
using Dog = Animal;

using Tom = Cat;
using Spike = Dog;
using Tyke = Dog;
```
For `X = Tom, Y = Spike`, this will result in `Animal`.
For `X = Spike, Y = Tyke`, this will result in `Dog`.

How it works:

We take two types, X and Y, which we wish to unify as input.
These types must have the same (qualified or unqualified) canonical
type.

We dive down fast through top-level type sugar nodes, to the
underlying canonical node. If these canonical nodes differ, we
build a common one out of the two, unifying any sugar they had.
Note that this might involve a recursive call to unify any children
of those. We then return that canonical node, handling any qualifiers.

If they don't differ, we walk up the list of sugar type nodes we dived
through, finding the last identical pair, and returning that as the
result, again handling qualifiers.

Note that this patch will not unify sugar nodes if they are not
identical already. We will simply strip off top-level sugar nodes that
differ between X and Y. This sugar node unification will instead be
implemented in a subsequent patch.

This patch also implements a few users of this mechanism:
* Template argument deduction.
* Auto deduction, for functions returning auto / decltype(auto), with
  special handling for initializer_list as well.

Further users will be implemented in a subsequent patch.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D111283
2022-09-08 19:17:48 +02:00
Kazu Hirata b7a7aeee90 [clang] Qualify auto in range-based for loops (NFC) 2022-09-03 23:27:27 -07:00
Shafik Yaghmour 9f6b3199d3 [Clang] Fix lambda CheckForDefaultedFunction(...) so that it checks the CXXMethodDecl is not deleted before attempting to call DefineDefaultedFunction(...)
I discovered this additional bug at the end of working on D132906

In Sema::CheckCompletedCXXClass(...)  uses a lambda CheckForDefaultedFunction to
verify each CXXMethodDecl holds to the expected invariants before passing them
on to CheckForDefaultedFunction.

It is currently missing a check that it is not deleted, this adds that check and
a test that crashed without this check.

This fixes: https://github.com/llvm/llvm-project/issues/57516

Differential Revision: https://reviews.llvm.org/D133177
2022-09-02 18:59:15 -07:00
Chris Bieneman 5b5329bd41 [NFC] Make MultiplexExternalSemaSource own sources
This change refactors the MuiltiplexExternalSemaSource to take ownership
of the underlying sources. As a result it makes a larger cleanup of
external source ownership in Sema and the ChainedIncludesSource.

Reviewed By: aaron.ballman, aprantl

Differential Revision: https://reviews.llvm.org/D133158
2022-09-02 13:57:39 -05:00
Shafik Yaghmour b9f7678846 [Clang] Fix lambda CheckForDefaultedFunction(...) so that it checks the CXXMethodDecl is a special member function before attempting to call DefineDefaultedFunction(...)
In Sema::CheckCompletedCXXClass(...) It used a lambda CheckForDefaultedFunction
the CXXMethodDecl passed to CheckForDefaultedFunction may not be a special
member function and so before attempting to apply functions that only apply to
special member functions it needs to check. It fails to do this before calling
DefineDefaultedFunction(...). This PR adds that check and test to verify we no
longer crash.

This fixes https://github.com/llvm/llvm-project/issues/57431

Differential Revision: https://reviews.llvm.org/D132906
2022-08-30 18:08:44 -07:00
Roy Jacobson b1c960fc6d [Clang] Implement P0848 (Conditionally Trivial Special Member Functions)
This patch implements P0848 in Clang.

During the instantiation of a C++ class, in `Sema::ActOnFields`, we evaluate constraints for all the SMFs and compare the constraints to compute the eligibility. We defer the computation of the type's [copy-]trivial bits from addedMember to the eligibility computation, like we did for destructors in D126194. `canPassInRegisters` is modified as well to better respect the ineligibility of functions.

Note: Because of the non-implementation of DR1734 and DR1496, I treat deleted member functions as 'eligible' for the purpose of [copy-]triviallity. This is unfortunate, but I couldn't think of a way to make this make sense otherwise.

Reviewed By: #clang-language-wg, cor3ntin, aaron.ballman

Differential Revision: https://reviews.llvm.org/D128619
2022-08-26 00:52:52 +03:00
Roy Jacobson 70770a16bc Revert "[Clang] Implement P0848 (Conditionally Trivial Special Member Functions)"
See bug report here: https://github.com/llvm/llvm-project/issues/57351
This reverts commit 7171615099.
2022-08-25 09:11:06 +03:00
Roy Jacobson 7171615099 [Clang] Implement P0848 (Conditionally Trivial Special Member Functions)
This patch implements P0848 in Clang.

During the instantiation of a C++ class, in `Sema::ActOnFields`, we evaluate constraints for all the SMFs and compare the constraints to compute the eligibility. We defer the computation of the type's [copy-]trivial bits from addedMember to the eligibility computation, like we did for destructors in D126194. `canPassInRegisters` is modified as well to better respect the ineligibility of functions.

Note: Because of the non-implementation of DR1734 and DR1496, I treat deleted member functions as 'eligible' for the purpose of [copy-]triviallity. This is unfortunate, but I couldn't think of a way to make this make sense otherwise.

Reviewed By: #clang-language-wg, cor3ntin, aaron.ballman

Differential Revision: https://reviews.llvm.org/D128619
2022-08-23 21:48:42 +03:00
Fred Tingaud ba1c396e09 MSVC compatibility mode: fix error on unqualified templated base class initialization in case of partial specialization
I introduced a patch to handle unqualified templated base class
initialization in MSVC compatibility mode:
https://reviews.llvm.org/rGc894e85fc64dd8d83b460de81080fff93c5ca334
We identified a problem with this patch in the case where the base class
is partially specialized, which can lead to triggering an assertion in
the case of a mix between types and values.
The minimal test case is:

  template <typename Type, int TSize> class Vec {};
  template <int TDim> class Index : public Vec<int, TDim> {
    Index() : Vec() {}
  };
  template class Index<0>;

The detailed problem is that I was using the
`InjectedClassNameSpecialization`, to which the class template arguments
were then applied in order. But in the process, we were losing all the
partial specializations of the base class and creating an index mismatch
between the expected and passed arguments.

Patch By: frederic-tingaud-sonarsource

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D130709
2022-08-16 17:09:55 +02:00
Utkarsh Saxena 72ac7cac3f Handle explicitly defaulted consteval special members.
Followup patch for D128083

Previously, using a non-consteval constructor from an consteval constructor would code generates the consteval constructor.
Example
```
template <typename T>
struct S {
  T i;
  consteval S() = default;
};
struct Foo {
    Foo() {}
};
void func() {
  S<Foo> three; // incorrectly accepted by clang.
}
```

This happened because clang erroneously disregards `consteval` specifier for a `consteval explicitly defaulted special member functions in a class template` if it has dependent data members without a `consteval default constructor`.

According to
```
C++14 [dcl.constexpr]p6 (CWG DR647/CWG DR1358):
If the instantiated template specialization of a constexpr function
template or member function of a class template would fail to satisfy
the requirements for a constexpr function or constexpr constructor, that
specialization is still a constexpr function or constexpr constructor,
even though a call to such a function cannot appear in a constant
expression.
```

Therefore the `consteval defaulted constructor of a class template` should be considered `consteval` even if the data members' default constructors are not consteval.
Keeping this constructor `consteval` allows complaining while processing the call to data member constructors.
(Same applies for other special member functions).

This works fine even when we have more than one default constructors since we process the constructors after the templates are instantiated.

This does not address initialization issues raised in
[2602](https://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#2602) and compiler divergence seen in https://godbolt.org/z/va9EMvvMe

Fixes: https://github.com/llvm/llvm-project/issues/51593

Differential Revision: https://reviews.llvm.org/D131479
2022-08-12 12:13:06 +02:00
Aaron Ballman 7309e8cfbe Do not use the same identifier for a data member as a type; NFC
This should help address a build failure found after
09117b2189

../tools/clang/lib/Sema/SemaDeclCXX.cpp: In member function ‘void clang::Sema::DiagnoseStaticAssertDetails(const clang::Expr*)’:
../tools/clang/lib/Sema/SemaDeclCXX.cpp:16666:19: error: declaration of ‘const clang::Expr* clang::Sema::DiagnoseStaticAssertDetails(const clang::Expr*)::<unnamed struct>::Expr’ changes meaning of ‘Expr’ [-fpermissive]
16666 |       const Expr *Expr;
      |                   ^~~~
In file included from ../tools/clang/include/clang/AST/DeclCXX.h:22,
                 from ../tools/clang/include/clang/AST/ASTLambda.h:18,
                 from ../tools/clang/lib/Sema/SemaDeclCXX.cpp:15:
../tools/clang/include/clang/AST/Expr.h:109:7: note: ‘Expr’ declared here as ‘class clang::Expr’
  109 | class Expr : public ValueStmt {
      |       ^~~~
2022-08-11 07:32:32 -04:00
Timm Bäder ebe0674acb [clang] Try to fix builders
Try to fix these errors:

SemaDeclCXX.cpp:16666:19: error: declaration of ‘const clang::Expr* clang::Sema::DiagnoseStaticAssertDetails(const clang::Expr*)::<unnamed struct>::Expr’ changes meaning of ‘Expr’ [-fpermissive]
16666 |       const Expr *Expr;
      |                   ^~~~
2022-08-11 09:07:44 +02:00
Timm Bäder 09117b2189 [clang][sema] Print more information about failed static assertions
For failed static assertions, try to take the expression apart and print
useful information about why it failed. In particular, look at binary
operators and print the compile-time evaluated value of the LHS/RHS.

Differential Revision: https://reviews.llvm.org/D130894
2022-08-11 08:44:38 +02:00
Fangrui Song 3f18f7c007 [clang] LLVM_FALLTHROUGH => [[fallthrough]]. NFC
With C++17 there is no Clang pedantic warning or MSVC C5051.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D131346
2022-08-08 09:12:46 -07:00
Matheus Izvekov 15f3cd6bfc
[clang] Implement ElaboratedType sugaring for types written bare
Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which goes against the intent that
we should produce an AST which retains enough details to recover how things are
written.

The lack of this sugar is incompatible with the intent of the type printer
default policy, which is to print types as written, but to fall back and print
them fully qualified when they are desugared.

An ElaboratedTypeLoc without keyword / NNS uses no storage by itself, but still
requires pointer alignment due to pre-existing bug in the TypeLoc buffer
handling.

---

Troubleshooting list to deal with any breakage seen with this patch:

1) The most likely effect one would see by this patch is a change in how
   a type is printed. The type printer will, by design and default,
   print types as written. There are customization options there, but
   not that many, and they mainly apply to how to print a type that we
   somehow failed to track how it was written. This patch fixes a
   problem where we failed to distinguish between a type
   that was written without any elaborated-type qualifiers,
   such as a 'struct'/'class' tags and name spacifiers such as 'std::',
   and one that has been stripped of any 'metadata' that identifies such,
   the so called canonical types.
   Example:
   ```
   namespace foo {
     struct A {};
     A a;
   };
   ```
   If one were to print the type of `foo::a`, prior to this patch, this
   would result in `foo::A`. This is how the type printer would have,
   by default, printed the canonical type of A as well.
   As soon as you add any name qualifiers to A, the type printer would
   suddenly start accurately printing the type as written. This patch
   will make it print it accurately even when written without
   qualifiers, so we will just print `A` for the initial example, as
   the user did not really write that `foo::` namespace qualifier.

2) This patch could expose a bug in some AST matcher. Matching types
   is harder to get right when there is sugar involved. For example,
   if you want to match a type against being a pointer to some type A,
   then you have to account for getting a type that is sugar for a
   pointer to A, or being a pointer to sugar to A, or both! Usually
   you would get the second part wrong, and this would work for a
   very simple test where you don't use any name qualifiers, but
   you would discover is broken when you do. The usual fix is to
   either use the matcher which strips sugar, which is annoying
   to use as for example if you match an N level pointer, you have
   to put N+1 such matchers in there, beginning to end and between
   all those levels. But in a lot of cases, if the property you want
   to match is present in the canonical type, it's easier and faster
   to just match on that... This goes with what is said in 1), if
   you want to match against the name of a type, and you want
   the name string to be something stable, perhaps matching on
   the name of the canonical type is the better choice.

3) This patch could expose a bug in how you get the source range of some
   TypeLoc. For some reason, a lot of code is using getLocalSourceRange(),
   which only looks at the given TypeLoc node. This patch introduces a new,
   and more common TypeLoc node which contains no source locations on itself.
   This is not an inovation here, and some other, more rare TypeLoc nodes could
   also have this property, but if you use getLocalSourceRange on them, it's not
   going to return any valid locations, because it doesn't have any. The right fix
   here is to always use getSourceRange() or getBeginLoc/getEndLoc which will dive
   into the inner TypeLoc to get the source range if it doesn't find it on the
   top level one. You can use getLocalSourceRange if you are really into
   micro-optimizations and you have some outside knowledge that the TypeLocs you are
   dealing with will always include some source location.

4) Exposed a bug somewhere in the use of the normal clang type class API, where you
   have some type, you want to see if that type is some particular kind, you try a
   `dyn_cast` such as `dyn_cast<TypedefType>` and that fails because now you have an
   ElaboratedType which has a TypeDefType inside of it, which is what you wanted to match.
   Again, like 2), this would usually have been tested poorly with some simple tests with
   no qualifications, and would have been broken had there been any other kind of type sugar,
   be it an ElaboratedType or a TemplateSpecializationType or a SubstTemplateParmType.
   The usual fix here is to use `getAs` instead of `dyn_cast`, which will look deeper
   into the type. Or use `getAsAdjusted` when dealing with TypeLocs.
   For some reason the API is inconsistent there and on TypeLocs getAs behaves like a dyn_cast.

5) It could be a bug in this patch perhaps.

Let me know if you need any help!

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D112374
2022-07-27 11:10:54 +02:00
Jonas Devlieghere 888673b6e3
Revert "[clang] Implement ElaboratedType sugaring for types written bare"
This reverts commit 7c51f02eff because it
stills breaks the LLDB tests. This was  re-landed without addressing the
issue or even agreement on how to address the issue. More details and
discussion in https://reviews.llvm.org/D112374.
2022-07-14 21:17:48 -07:00
Matheus Izvekov 7c51f02eff
[clang] Implement ElaboratedType sugaring for types written bare
Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which goes against the intent that
we should produce an AST which retains enough details to recover how things are
written.

The lack of this sugar is incompatible with the intent of the type printer
default policy, which is to print types as written, but to fall back and print
them fully qualified when they are desugared.

An ElaboratedTypeLoc without keyword / NNS uses no storage by itself, but still
requires pointer alignment due to pre-existing bug in the TypeLoc buffer
handling.

---

Troubleshooting list to deal with any breakage seen with this patch:

1) The most likely effect one would see by this patch is a change in how
   a type is printed. The type printer will, by design and default,
   print types as written. There are customization options there, but
   not that many, and they mainly apply to how to print a type that we
   somehow failed to track how it was written. This patch fixes a
   problem where we failed to distinguish between a type
   that was written without any elaborated-type qualifiers,
   such as a 'struct'/'class' tags and name spacifiers such as 'std::',
   and one that has been stripped of any 'metadata' that identifies such,
   the so called canonical types.
   Example:
   ```
   namespace foo {
     struct A {};
     A a;
   };
   ```
   If one were to print the type of `foo::a`, prior to this patch, this
   would result in `foo::A`. This is how the type printer would have,
   by default, printed the canonical type of A as well.
   As soon as you add any name qualifiers to A, the type printer would
   suddenly start accurately printing the type as written. This patch
   will make it print it accurately even when written without
   qualifiers, so we will just print `A` for the initial example, as
   the user did not really write that `foo::` namespace qualifier.

2) This patch could expose a bug in some AST matcher. Matching types
   is harder to get right when there is sugar involved. For example,
   if you want to match a type against being a pointer to some type A,
   then you have to account for getting a type that is sugar for a
   pointer to A, or being a pointer to sugar to A, or both! Usually
   you would get the second part wrong, and this would work for a
   very simple test where you don't use any name qualifiers, but
   you would discover is broken when you do. The usual fix is to
   either use the matcher which strips sugar, which is annoying
   to use as for example if you match an N level pointer, you have
   to put N+1 such matchers in there, beginning to end and between
   all those levels. But in a lot of cases, if the property you want
   to match is present in the canonical type, it's easier and faster
   to just match on that... This goes with what is said in 1), if
   you want to match against the name of a type, and you want
   the name string to be something stable, perhaps matching on
   the name of the canonical type is the better choice.

3) This patch could exposed a bug in how you get the source range of some
   TypeLoc. For some reason, a lot of code is using getLocalSourceRange(),
   which only looks at the given TypeLoc node. This patch introduces a new,
   and more common TypeLoc node which contains no source locations on itself.
   This is not an inovation here, and some other, more rare TypeLoc nodes could
   also have this property, but if you use getLocalSourceRange on them, it's not
   going to return any valid locations, because it doesn't have any. The right fix
   here is to always use getSourceRange() or getBeginLoc/getEndLoc which will dive
   into the inner TypeLoc to get the source range if it doesn't find it on the
   top level one. You can use getLocalSourceRange if you are really into
   micro-optimizations and you have some outside knowledge that the TypeLocs you are
   dealing with will always include some source location.

4) Exposed a bug somewhere in the use of the normal clang type class API, where you
   have some type, you want to see if that type is some particular kind, you try a
   `dyn_cast` such as `dyn_cast<TypedefType>` and that fails because now you have an
   ElaboratedType which has a TypeDefType inside of it, which is what you wanted to match.
   Again, like 2), this would usually have been tested poorly with some simple tests with
   no qualifications, and would have been broken had there been any other kind of type sugar,
   be it an ElaboratedType or a TemplateSpecializationType or a SubstTemplateParmType.
   The usual fix here is to use `getAs` instead of `dyn_cast`, which will look deeper
   into the type. Or use `getAsAdjusted` when dealing with TypeLocs.
   For some reason the API is inconsistent there and on TypeLocs getAs behaves like a dyn_cast.

5) It could be a bug in this patch perhaps.

Let me know if you need any help!

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D112374
2022-07-15 04:16:55 +02:00
Jonas Devlieghere 3968936b92
Revert "[clang] Implement ElaboratedType sugaring for types written bare"
This reverts commit bdc6974f92 because it
breaks all the LLDB tests that import the std module.

  import-std-module/array.TestArrayFromStdModule.py
  import-std-module/deque-basic.TestDequeFromStdModule.py
  import-std-module/deque-dbg-info-content.TestDbgInfoContentDequeFromStdModule.py
  import-std-module/forward_list.TestForwardListFromStdModule.py
  import-std-module/forward_list-dbg-info-content.TestDbgInfoContentForwardListFromStdModule.py
  import-std-module/list.TestListFromStdModule.py
  import-std-module/list-dbg-info-content.TestDbgInfoContentListFromStdModule.py
  import-std-module/queue.TestQueueFromStdModule.py
  import-std-module/stack.TestStackFromStdModule.py
  import-std-module/vector.TestVectorFromStdModule.py
  import-std-module/vector-bool.TestVectorBoolFromStdModule.py
  import-std-module/vector-dbg-info-content.TestDbgInfoContentVectorFromStdModule.py
  import-std-module/vector-of-vectors.TestVectorOfVectorsFromStdModule.py

https://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/45301/
2022-07-13 09:20:30 -07:00