Commit Graph

1156 Commits

Author SHA1 Message Date
Mike Rice 2cedaee6f7 [OpenMP] Initial parsing/sema for the 'omp parallel loop' construct
Adds basic parsing/sema/serialization support for the
  #pragma omp parallel loop directive.

 Differential Revision: https://reviews.llvm.org/D122247
2022-03-22 13:55:47 -07:00
Mike Rice 6bd8dc91b8 [OpenMP] Initial parsing/sema for the 'omp target teams loop' construct
Adds basic parsing/sema/serialization support for the
 #pragma omp target teams loop directive.

Differential Revision: https://reviews.llvm.org/D122028
2022-03-18 13:48:32 -07:00
Mike Rice 79f661edc1 [OpenMP] Initial parsing/sema for the 'omp teams loop' construct
Adds basic parsing/sema/serialization support for the #pragma omp teams loop
directive.

Differential Revision: https://reviews.llvm.org/D121713
2022-03-16 14:39:18 -07:00
Yonghong Song 3251ba2d0f [Attr] Fix a btf_type_tag AST generation
Current ASTContext.getAttributedType() takes attribute kind,
ModifiedType and EquivType as the hash to decide whether an AST node
has been generated or note. But this is not enough for btf_type_tag
as the attribute might have the same ModifiedType and EquivType, but
still have different string associated with attribute.

For example, for a data structure like below,
  struct map_value {
        int __attribute__((btf_type_tag("tag1"))) __attribute__((btf_type_tag("tag3"))) *a;
        int __attribute__((btf_type_tag("tag2"))) __attribute__((btf_type_tag("tag4"))) *b;
  };
The current ASTContext.getAttributedType() will produce
an AST similar to below:
  struct map_value {
        int __attribute__((btf_type_tag("tag1"))) __attribute__((btf_type_tag("tag3"))) *a;
        int __attribute__((btf_type_tag("tag1"))) __attribute__((btf_type_tag("tag3"))) *b;
  };
and this is incorrect.

It is very difficult to use the current AttributedType as it is hard to
get the tag information. To fix the problem, this patch introduced
BTFTagAttributedType which is similar to AttributedType
in many ways but with an additional BTFTypeTagAttr. The tag itself can
be retrieved with BTFTypeTagAttr.
With the new BTFTagAttributed type, the debuginfo code can be greatly
simplified compared to previous TypeLoc based approach.

Differential Revision: https://reviews.llvm.org/D120296
2022-03-16 08:46:52 -07:00
Argyrios Kyrtzidis f2b24905bf [Sema] Mark the referenced destructor during transformation of a `CXXBindTemporaryExpr`
Otherwise we will fail to generate the definition of a defaulted destructor,
if the only reference was in a templated temporary.

rdar://89366678

Differential Revision: https://reviews.llvm.org/D120426
2022-03-08 01:00:07 -08:00
Timm Bäder f8cedc642d [clang] Never wrap a nullptr in CXXNewExpr::getArraySize()
Otherwise callers of these functions have to check both the return value
for and the contents of the returned llvm::Optional.

Fixes #53742

Differential Revision: https://reviews.llvm.org/D119525
2022-02-22 16:27:32 +01:00
Chuanqi Xu d30ca5e2e2 [C++20] [Coroutines] Implement return value optimization for get_return_object
This patch tries to implement RVO for coroutine's return object got from
get_return_object.
From [dcl.fct.def.coroutine]/p7 we could know that the return value of
get_return_object is either a reference or a prvalue. So it makes sense
to do copy elision for the return value. The return object should be
constructed directly into the storage where they would otherwise be
copied/moved to.

Test Plan: folly, check-all

Reviewed By: junparser

Differential revision: https://reviews.llvm.org/D117087
2022-02-16 13:38:00 +08:00
Corentin Jabot c151225096 [C++2b] Implement multidimentional subscript operator
Implement P2128R6 in C++23 mode.

Unlike GCC's implementation, this doesn't try to recover when a user
meant to use a comma expression.

Because the syntax changes meaning in C++23, the patch is *NOT*
implemented as an extension. Instead, declaring an array with not
exactly 1 parameter is an error in older languages modes. There is an
off-by-default extension warning in C++23 mode.

Unlike the standard, we supports default arguments;

Ie, we assume, based on conversations in WG21, that the proposed
resolution to CWG2507 will be accepted.

We allow arrays OpenMP sections and C++23 multidimensional array to
coexist:

[a , b] multi dimensional array
[a : b] open mp section
[a, b: c] // error

The rest of the patch is relatively straight forward: we take care to
support an arbitrary number of arguments everywhere.
2022-02-08 12:10:47 -05:00
Arthur O'Dwyer f6ce456707 [clang] Correctly(?) handle placeholder types in ExprRequirements.
Bug #52905 was originally papered over in a different way, but
I believe this is the actually proper fix, or at least closer to
it. We need to detect placeholder types as close to the front-end
as possible, and cause them to fail constraints, rather than letting
them persist into later stages.

Fixes #52905.
Fixes #52909.
Fixes #53075.

Differential Revision: https://reviews.llvm.org/D118552
2022-02-01 15:16:17 -05:00
Benjamin Kramer f15014ff54 Revert "Rename llvm::array_lengthof into llvm::size to match std::size from C++17"
This reverts commit ef82063207.

- It conflicts with the existing llvm::size in STLExtras, which will now
  never be called.
- Calling it without llvm:: breaks C++17 compat
2022-01-26 16:55:53 +01:00
serge-sans-paille ef82063207 Rename llvm::array_lengthof into llvm::size to match std::size from C++17
As a conquence move llvm::array_lengthof from STLExtras.h to
STLForwardCompat.h (which is included by STLExtras.h so no build
breakage expected).
2022-01-26 16:17:45 +01:00
Haojian Wu ab3f100bec Reland (2) "[AST] Add RParen loc for decltype AutoTypeloc.""
The patch was reverted because it caused a crash during PCH build -- we
missed to update the RParenLoc in TreeTransform<Derived>::TransformAutoType.

This relands 55d96ac and 37ec65e with a test and fix.
2022-01-17 11:33:11 +01:00
Sam McCall 27ea0c4e72 [Parse] Use empty RecoveryExpr when if/while/do/switch conditions fail to parse
This allows the body to be parsed.
An special-case that would replace a missing if condition with OpaqueValueExpr
was removed as it's now redundant (unless recovery-expr is disabled).

For loops are not handled at this point, as the parsing is more complicated.

Differential Revision: https://reviews.llvm.org/D113752
2022-01-10 10:38:27 +01:00
Haojian Wu 4a4b8e4f99 [AST] Add more source information for DecltypeTypeLoc.
Adds the paren source location, and removes the hack in clangd.

Differential Revision: https://reviews.llvm.org/D116793
2022-01-10 09:34:18 +01:00
Shilei Tian c7a589a2c4 [Clang][OpenMP] Add the support for atomic compare in parser
This patch adds the support for `atomic compare` in parser. The support
in Sema and CodeGen will come soon. For now, it simply eimits an error when it
is encountered.

Reviewed By: ABataev

Differential Revision: https://reviews.llvm.org/D115561
2021-12-24 08:16:51 -05:00
Sam McCall af27466c50 Reland "[AST] Add UsingType: a sugar type for types found via UsingDecl"
This reverts commit cc56c66f27.
Fixed a bad assertion, the target of a UsingShadowDecl must not have
*local* qualifiers, but it can be a typedef whose underlying type is qualified.
2021-12-20 18:03:15 +01:00
Sam McCall cc56c66f27 Revert "[AST] Add UsingType: a sugar type for types found via UsingDecl"
This reverts commit e1600db19d.

Breaks sanitizer tests, at least on windows:
https://lab.llvm.org/buildbot/#/builders/127/builds/21592/steps/4/logs/stdio
2021-12-20 17:53:56 +01:00
Sam McCall e1600db19d [AST] Add UsingType: a sugar type for types found via UsingDecl
Currently there's no way to find the UsingDecl that a typeloc found its
underlying type through. Compare to DeclRefExpr::getFoundDecl().

Design decisions:
- a sugar type, as there are many contexts this type of use may appear in
- UsingType is a leaf like TypedefType, the underlying type has no TypeLoc
- not unified with UnresolvedUsingType: a single name is appealing,
  but being sometimes-sugar is often fiddly.
- not unified with TypedefType: the UsingShadowDecl is not a TypedefNameDecl or
  even a TypeDecl, and users think of these differently.
- does not cover other rarer aliases like objc @compatibility_alias,
  in order to be have a concrete API that's easy to understand.
- implicitly desugared by the hasDeclaration ASTMatcher, to avoid
  breaking existing patterns and following the precedent of ElaboratedType.

Scope:
- This does not cover types associated with template names introduced by
  using declarations. A future patch should introduce a sugar TemplateName
  variant for this. (CTAD deduced types fall under this)
- There are enough AST matchers to fix the in-tree clang-tidy tests and
  probably any other matchers, though more may be useful later.

Caveats:
- This changes a fairly common pattern in the AST people may depend on matching.
  Previously, typeLoc(loc(recordType())) matched whether a struct was
  referred to by its original scope or introduced via using-decl.
  Now, the using-decl case is not matched, and needs a separate matcher.
  This is similar to the case of typedefs but nevertheless both adds
  complexity and breaks existing code.

Differential Revision: https://reviews.llvm.org/D114251
2021-12-20 17:15:38 +01:00
Aaron Ballman 6c75ab5f66 Introduce _BitInt, deprecate _ExtInt
WG14 adopted the _ExtInt feature from Clang for C23, but renamed the
type to be _BitInt. This patch does the vast majority of the work to
rename _ExtInt to _BitInt, which accounts for most of its size. The new
type is exposed in older C modes and all C++ modes as a conforming
extension. However, there are functional changes worth calling out:

* Deprecates _ExtInt with a fix-it to help users migrate to _BitInt.
* Updates the mangling for the type.
* Updates the documentation and adds a release note to warn users what
is going on.
* Adds new diagnostics for use of _BitInt to call out when it's used as
a Clang extension or as a pre-C23 compatibility concern.
* Adds new tests for the new diagnostic behaviors.

I want to call out the ABI break specifically. We do not believe that
this break will cause a significant imposition for early adopters of
the feature, and so this is being done as a full break. If it turns out
there are critical uses where recompilation is not an option for some
reason, we can consider using ABI tags to ease the transition.
2021-12-06 12:52:01 -05:00
Jeroen Dobbelaere a4fbae268f Revert "[Sema] check PseudoObject when rebuilding CXXOperatorCallExpr in template instantiation"
This reverts commit 0c047a8e13.

A number of buildbots started failing. Reverting for now.
2021-12-01 11:18:30 +01:00
Jeroen Dobbelaere 0c047a8e13 [Sema] check PseudoObject when rebuilding CXXOperatorCallExpr in template instantiation
The invocation of a unary or binary operator for type-dependent expressions is represented as a CXXOperatorCallExpr. Upon template instantiation, TreeTransform::RebuildCXXOperatorCallExpr checks for the case of an overloaded operator, but not for a (non-ObjC) PseudoObject, and will directly create a UnaryOperator or BinaryOperator.

Generalizing commit 0f99537eca from @akyrtzi to handle non-ObjC pseudo objects (and also handle the case of unary pseudo object inc/dec).

This fixes https://bugs.llvm.org/show_bug.cgi?id=51855

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D111639
2021-12-01 11:02:28 +01:00
Richard Smith 4a9523c55f PR52537: When performing a no-op TreeTransform of a rewritten binary
operator, mark any functions it calls as referenced.
2021-11-17 18:19:46 -08:00
Matheus Izvekov c9e46219f3
[clang] retain type sugar in auto / template argument deduction
This implements the following changes:
* AutoType retains sugared deduced-as-type.
* Template argument deduction machinery analyses the sugared type all the way
down. It would previously lose the sugar on first recursion.
* Undeduced AutoType will be properly canonicalized, including the constraint
template arguments.
* Remove the decltype node created from the decltype(auto) deduction.

As a result, we start seeing sugared types in a lot more test cases,
including some which showed very unfriendly `type-parameter-*-*` types.

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

Reviewed By: rsmith, #libc, ldionne

Differential Revision: https://reviews.llvm.org/D110216
2021-11-15 23:07:45 +01:00
Matheus Izvekov 6438a52df1
Revert "[clang] retain type sugar in auto / template argument deduction"
This reverts commit 4d8fff477e.
2021-11-15 00:29:05 +01:00
Matheus Izvekov 4d8fff477e
[clang] retain type sugar in auto / template argument deduction
This implements the following changes:
* AutoType retains sugared deduced-as-type.
* Template argument deduction machinery analyses the sugared type all the way
down. It would previously lose the sugar on first recursion.
* Undeduced AutoType will be properly canonicalized, including the constraint
template arguments.
* Remove the decltype node created from the decltype(auto) deduction.

As a result, we start seeing sugared types in a lot more test cases,
including some which showed very unfriendly `type-parameter-*-*` types.

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

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D110216
2021-11-13 03:35:22 +01:00
Adrian Kuegel 1d7fdbbc18 Revert "[clang] retain type sugar in auto / template argument deduction"
This reverts commit 9b6036deed.
Breaks two libc++ tests.
2021-11-12 13:21:59 +01:00
Matheus Izvekov 9b6036deed
[clang] retain type sugar in auto / template argument deduction
This implements the following changes:
* AutoType retains sugared deduced-as-type.
* Template argument deduction machinery analyses the sugared type all the way
down. It would previously lose the sugar on first recursion.
* Undeduced AutoType will be properly canonicalized, including the constraint
template arguments.
* Remove the decltype node created from the decltype(auto) deduction.

As a result, we start seeing sugared types in a lot more test cases,
including some which showed very unfriendly `type-parameter-*-*` types.

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

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D110216
2021-11-12 01:16:31 +01:00
David Pagan b0de656bdf Initial parsing/sema for 'align' clause
Added basic parsing/sema/serialization support for 'align' clause for use with
'allocate' directive.
2021-11-09 07:34:18 -05:00
Jason Rice b5aef90d46 [Clang] Fix instantiation of OpaqueValueExprs (Bug #45964)
The structured bindings decomposition of a non-dependent array in a dependent context (a template) were, upon instantiation, creating nested OpaqueValueExprs that would trigger assertions in CodeGen. Additionally the OpaqueValuesExpr's contained SourceExpr is being emitted in CodeGen, but there was no code for its transform in template instantiation. This would trigger other assertions such as when emitting a DeclRefExpr that refers to a VarDecl that is not marked as ODR-used.

This is all based on cursory deduction, but with the way the code flows from SemaTemplateInstantiate back to SemaInit, it is apparent that the nesting of OpaqueValueExpr is unintentional.

This commit fixes https://bugs.llvm.org/show_bug.cgi?id=45964 and possible other issues involving OpaqueValueExprs in template instantiations might be resolved.

Reviewed By: aaron.ballman, rjmccall

Differential Revision: https://reviews.llvm.org/D108482
2021-11-06 10:06:38 +02:00
Mike Rice 4eac7bcf1a [OpenMP] Add parsing/sema/serialization for 'bind' clause.
Differential Revision: https://reviews.llvm.org/D113154
2021-11-04 14:40:30 -07:00
Mike Rice 6f9c25167d [OpenMP] Initial parsing/sema for the 'omp loop' construct
Adds basic parsing/sema/serialization support for the #pragma omp loop
directive.

Differential Revision: https://reviews.llvm.org/D112499
2021-10-28 08:26:43 -07:00
Corentin Jabot 424733c12a Implement if consteval (P1938)
Modify the IfStmt node to suppoort constant evaluated expressions.

Add a new ExpressionEvaluationContext::ImmediateFunctionContext to
keep track of immediate function contexts.

This proved easier/better/probably more efficient than walking the AST
backward as it allows diagnosing nested if consteval statements.
2021-10-05 08:04:14 -04:00
Andy Wingo 9ae4275557 [clang][NFC] Fix needless double-parenthisation
Strip a layer of parentheses in TreeTransform::RebuildQualifiedType.

Differential Revision: https://reviews.llvm.org/D108359
2021-09-21 17:03:23 +02:00
Nico Weber bde305baf6 [clang] Fix a few comment more typos to cycle bots 2021-09-20 19:42:49 -04:00
alokmishra.besu 000875c127 OpenMP 5.0 metadirective
This patch supports OpenMP 5.0 metadirective features.
It is implemented keeping the OpenMP 5.1 features like dynamic user condition in mind.

A new function, getBestWhenMatchForContext, is defined in llvm/Frontend/OpenMP/OMPContext.h

Currently this function return the index of the when clause with the highest score from the ones applicable in the Context.
But this function is declared with an array which can be used in OpenMP 5.1 implementation to select all the valid when clauses which can be resolved in runtime. Currently this array is set to null by default and its implementation is left for future.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D91944
2021-09-18 13:40:44 -05:00
Nico Weber 31cca21565 Revert "OpenMP 5.0 metadirective"
This reverts commit c7d7b98e52.
Breaks tests on macOS, see comment on https://reviews.llvm.org/D91944
2021-09-18 09:10:37 -04:00
alokmishra.besu 347f3c186d OpenMP 5.0 metadirective
This patch supports OpenMP 5.0 metadirective features.
It is implemented keeping the OpenMP 5.1 features like dynamic user condition in mind.

A new function, getBestWhenMatchForContext, is defined in llvm/Frontend/OpenMP/OMPContext.h

Currently this function return the index of the when clause with the highest score from the ones applicable in the Context.
But this function is declared with an array which can be used in OpenMP 5.1 implementation to select all the valid when clauses which can be resolved in runtime. Currently this array is set to null by default and its implementation is left for future.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D91944
2021-09-17 16:30:06 -05:00
cchen 7efb825382 Revert "OpenMP 5.0 metadirective"
This reverts commit c7d7b98e52.
2021-09-17 16:14:16 -05:00
cchen c7d7b98e52 OpenMP 5.0 metadirective
This patch supports OpenMP 5.0 metadirective features.
It is implemented keeping the OpenMP 5.1 features like dynamic user condition in mind.

A new function, getBestWhenMatchForContext, is defined in llvm/Frontend/OpenMP/OMPContext.h

Currently this function return the index of the when clause with the highest score from the ones applicable in the Context.
But this function is declared with an array which can be used in OpenMP 5.1 implementation to select all the valid when clauses which can be resolved in runtime. Currently this array is set to null by default and its implementation is left for future.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D91944
2021-09-17 16:03:13 -05:00
Matheus Izvekov 68b9d8ed7a [clang] fix transformation of template arguments of 'auto' type constraints
See PR48617.

When assigning the new template arguments to the new TypeLoc, we were looping
on the argument count of the original TypeLoc instead of the new one,
which can be different when packs are present.

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

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D109406
2021-09-08 03:22:34 +02:00
Jennifer Yu c274b19866 Add implicit map for a list item appears in a reduction clause.
A new rule is added in 5.0:
If a list item appears in a reduction, lastprivate or linear clause
on a combined target construct then it is treated as if it also appears
in a map clause with a map-type of tofrom.

Currently map clauses for all capture variables are added implicitly.
But missing for list item of expression for array elements or array
sections.

The change is to add implicit map clause for array of elements used in
reduction clause. Skip adding map clause if the expression is not
mappable.
Noted: For linear and lastprivate, since only variable name is
accepted, the map has been added though capture variables.

To do so:
During the mappable checking, if error, ignore diagnose and skip
adding implicit map clause.

The changes:
1> Add code to generate implicit map in ActOnOpenMPExecutableDirective,
   for omp 5.0 and up.
2> Add extra default parameter NoDiagnose in ActOnOpenMPMapClause:
Use that to skip error as well as skip adding implicit map during the
mappable checking.

Note: there are only tow places need to be check for NoDiagnose. Rest
of them either the check is for < omp 5.0 or the error already generated for
reduction clause.

Differential Revision: https://reviews.llvm.org/D108132
2021-08-19 12:53:47 -07:00
Corentin Jabot 3c8e94bc20 Disallow narrowing conversions to bool in noexcept specififers
Completes the support for P1401R5.
2021-08-06 10:26:39 -04:00
Zhouyi Zhou 2fd75507d1 [clang] NFC: add line break at the end of if expressions
Hi,

In function TransformTemplateArgument,
would it be better to add line break at the end of "if" expressions?

I use clang-format to do the job for me.

Thanks a lot

Reviewed By: pengfei

Differential Revision: https://reviews.llvm.org/D104604
2021-06-30 19:48:24 +08:00
Bruno Cardoso Lopes c9aaf34b8d [SemaCXX] Handle lack of TypeSourceInfo on special member functions in templated lambdas
During template instantiation involving templated lambdas, clang
could hit an assertion in `TemplateDeclInstantiator::SubstFunctionType`
since the functions are not associated with any `TypeSourceInfo`:

`assert(OldTInfo && "substituting function without type source info");`

This path is triggered when using templated lambdas like the one added as
a test to this patch. To fix this:

- Create `TypeSourceInfo`s for special members and make sure the template
instantiator can get through all patterns.
- Introduce a `SpecialMemberTypeInfoRebuilder` tree transform to rewrite
such member function arguments. Without this, we get errors like:

`error: only special member functions and comparison operators may be defaulted`

since `getDefaultedFunctionKind` can't properly recognize these functions
as special members as part of `SetDeclDefaulted`.

Fixes PR45828 and PR44848

Differential Revision: https://reviews.llvm.org/D88327
2021-06-22 17:26:05 -07:00
Zhouyi Zhou 735ad67a4c [clang] NFC: adjust indentation of statements with more than one lines
Hi,

I think it will be more beautiful to adjust indentation of statements with more than one lines.

In function TreeTransform<Derived>::TransformDependentScopeDeclRefExpr
the second line of statement
NestedNameSpecifierLoc QualifierLoc \newline = getDerived().TransformNestedNameSpecifierLoc(E->getQualifierLoc());
is no more indent than the first line

There is a similar case in function TreeTransform<Derived>::TransformUnresolvedMemberExpr

Also I use clang-format to fix above functions

Thanks alot

Reviewed By: pengfei

Differential Revision: https://reviews.llvm.org/D104145
2021-06-21 10:17:10 +08:00
Michael Kruse a22236120f [OpenMP] Implement '#pragma omp unroll'.
Implementation of the unroll directive introduced in OpenMP 5.1. Follows the approach from D76342 for the tile directive (i.e. AST-based, not using the OpenMPIRBuilder). Tries to use `llvm.loop.unroll.*` metadata where possible, but has to fall back to an AST representation of the outer loop if the partially unrolled generated loop is associated with another directive (because it needs to compute the number of iterations).

Reviewed By: ABataev

Differential Revision: https://reviews.llvm.org/D99459
2021-06-10 14:30:17 -05:00
Matheus Izvekov aef5d8fdc7 [clang] NFC: Rename rvalue to prvalue
This renames the expression value categories from rvalue to prvalue,
keeping nomenclature consistent with C++11 onwards.

C++ has the most complicated taxonomy here, and every other language
only uses a subset of it, so it's less confusing to use the C++ names
consistently, and mentally remap to the C names when working on that
context (prvalue -> rvalue, no xvalues, etc).

Renames:
* VK_RValue -> VK_PRValue
* Expr::isRValue -> Expr::isPRValue
* SK_QualificationConversionRValue -> SK_QualificationConversionPRValue
* JSON AST Dumper Expression nodes value category: "rvalue" -> "prvalue"

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

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D103720
2021-06-09 12:27:10 +02:00
Erich Keane 8beaca8c14 Remove unused function from a previous iteration of unique-stable-name 2021-06-02 12:15:16 -07:00
Erik Pilkington 369c648399 [clang] Implement the using_if_exists attribute
This attribute applies to a using declaration, and permits importing a
declaration without knowing if that declaration exists. This is useful
for libc++ C wrapper headers that re-export declarations in std::, in
cases where the base C library doesn't provide all declarations.

This attribute was proposed in http://lists.llvm.org/pipermail/cfe-dev/2020-June/066038.html.

rdar://69313357

Differential Revision: https://reviews.llvm.org/D90188
2021-06-02 10:30:24 -04:00
Nathan Sidwell c138f3ce5c [clang] Fix ICE with typeid & polymorphic class (pr50497)
This addresses pr50497. The argument of a typeid expression is
unevaluated, *except* when it's a polymorphic type. We handle this by
parsing as unevaluated and then transforming to evaluated if we
discover it should have been an evaluated context.

We do the same in TreeTransform<Derived>::TransformCXXTypeidExpr,
entering unevaluated context before transforming and rebuilding the
typeid. But that's incorrect and can lead us to converting to
evaluated context twice -- and hitting an assert.

During normal template instantiation we're always cloning the
expression, but during generic lambda processing we do not necessarily
AlwaysRebuild, and end up with TransformDeclRefExpr unconditionally
calling MarkDeclRefReferenced around line 10226. That triggers the
assert.

// Mark it referenced in the new context regardless.
// FIXME: this is a bit instantiation-specific.
SemaRef.MarkDeclRefReferenced(E);

This patch makes 2 changes.

a) TreeTransform<Derived>::TransformCXXTypeidExpr only enters
unevaluated context if the typeid's operand is not a polymorphic
glvalue. If it is, it keeps the same evaluation context.

b) Sema::BuildCXXTypeId is altered to only transform to evaluated, if
the current context is unevaluated.

Differential Revision: https://reviews.llvm.org/D103258
2021-06-01 12:55:29 -07:00