nullptr_t does not access memory.
We now reuse CK_NullToPointer to represent a conversion from a glvalue
of type nullptr_t to a prvalue of nullptr_t where necessary.
This reinstates r363337, reverted in r363352.
llvm-svn: 363429
Summary:
When a variable is named in a context where we can't directly emit a
reference to it (because we don't know for sure that it's going to be
defined, or it's from an enclosing function and not captured, or the
reference might not "work" for some reason), we emit a copy of the
variable as a global and use that for the known-to-be-read-only access.
This reinstates r363295, reverted in r363352, with a fix for PR42276:
we now produce a proper name for a non-odr-use reference to a static
constexpr data member. The name <mangled-name>.const is used in that
case; such names are reserved to the implementation for cases such as
this and should demangle nicely.
Reviewers: rjmccall
Subscribers: jdoerfert, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D63157
llvm-svn: 363428
Revert 363340 "Remove unused SK_LValueToRValue initialization step."
Revert 363337 "PR23833, DR2140: an lvalue-to-rvalue conversion on a glvalue of type"
Revert 363295 "C++ DR712 and others: handle non-odr-use resulting from an lvalue-to-rvalue conversion applied to a member access or similar not-quite-trivial lvalue expression."
llvm-svn: 363352
nullptr_t does not access memory.
We now reuse CK_NullToPointer to represent a conversion from a glvalue
of type nullptr_t to a prvalue of nullptr_t where necessary.
This reinstates r345562, reverted in r346065, now that CodeGen's
handling of non-odr-used variables has been fixed.
llvm-svn: 363337
Summary:
When a variable is named in a context where we can't directly emit a
reference to it (because we don't know for sure that it's going to be
defined, or it's from an enclosing function and not captured, or the
reference might not "work" for some reason), we emit a copy of the
variable as a global and use that for the known-to-be-read-only access.
Reviewers: rjmccall
Subscribers: jdoerfert, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D63157
llvm-svn: 363295
object rather than tracking the originating expression.
This is groundwork for supporting polymorphic typeid expressions. (Note
that this somewhat regresses our support for DR1968, but it turns out
that that never actually worked anyway, at least in non-trivial cases.)
This reinstates r360974, reverted in r360988, with a fix for a
static_assert failure on 32-bit builds: force Type base class to have
8-byte alignment like the rest of Clang's AST nodes.
llvm-svn: 360995
object rather than tracking the originating expression.
This is groundwork for supporting polymorphic typeid expressions. (Note
that this somewhat regresses our support for DR1968, but it turns out
that that never actually worked anyway, at least in non-trivial cases.)
llvm-svn: 360974
The change breaks libc++ with the follwing error:
In file included from valarray:4:
.../include/c++/v1/valarray:1062:60: error: explicit instantiation declaration of 'valarray<_Tp>' with internal linkage
_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS valarray<size_t>::valarray(size_t))
^
.../include/c++/v1/valarray:1063:60: error: explicit instantiation declaration of '~valarray<_Tp>' with internal linkage
_LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS valarray<size_t>::~valarray())
llvm-svn: 359076
template specialization if there is no matching non-template function.
This exposed a couple of related bugs:
- we would sometimes substitute into a friend template instead of a
suitable non-friend declaration; this would now crash because we'd
decide the specialization of the friend is a redeclaration of itself
- ADL failed to properly handle the case where an invisible local
extern declaration redeclares an invisible friend
Both are fixed herein: in particular, we now never make invisible
friends or local extern declarations visible to name lookup unless
they are the only declaration of the entity. (We already mostly did
this for local extern declarations.)
llvm-svn: 350505
This exposes a (known) CodeGen bug: it can't cope with emitting lvalue
expressions that denote non-odr-used but usable-in-constant-expression
variables. See PR39528 for a testcase.
Reverted for now until that issue can be fixed.
llvm-svn: 346065
nullptr_t does not access memory.
We now reuse CK_NullToPointer to represent a conversion from a glvalue
of type nullptr_t to a prvalue of nullptr_t where necessary.
llvm-svn: 345562
Summary:
This change rejects the shadowing of a capture by a parameter in lambdas in C++17.
```
int main() {
int a;
auto f = [a](int a) { return a; };
}
```
results in:
```
main.cpp:3:20: error: a lambda parameter cannot shadow an explicitly captured entity
auto f = [a](int a) { return a; };
^
main.cpp:3:13: note: variable a is explicitly captured here
auto f = [a](int a) { return a; };
^
```
Reviewers: rsmith
Reviewed By: rsmith
Subscribers: lebedev.ri, erik.pilkington, cfe-commits
Differential Revision: https://reviews.llvm.org/D53595
llvm-svn: 345308
This change implements C++ DR1696, which makes initialization of a
reference member of a class from a temporary object ill-formed. The
standard wording here is imprecise, but we interpret it as meaning that
any time a mem-initializer would result in lifetime extension, the
program is ill-formed.
This reinstates r337226, reverted in r337255, with a fix for the
InitializedEntity alignment problem that was breaking ARM buildbots.
llvm-svn: 337329
This change breaks on ARM because pointers to clang::InitializedEntity are only
4 byte aligned and do not have 3 bits to store values. A possible solution
would be to change the fields in clang::InitializedEntity to enforce a bigger
alignment requirement.
The error message is
llvm/include/llvm/ADT/PointerIntPair.h:132:3: error: static_assert failed "PointerIntPair with integer size too large for pointer"
static_assert(IntBits <= PtrTraits::NumLowBitsAvailable,
include/llvm/ADT/PointerIntPair.h:73:13: note: in instantiation of template class 'llvm::PointerIntPairInfo<const clang::InitializedEntity *, 3, llvm::PointerLikeTypeTraits<const clang::InitializedEntity *> >' requested here
Value = Info::updateInt(Info::updatePointer(0, PtrVal),
llvm/include/llvm/ADT/PointerIntPair.h:51:5: note: in instantiation of member function 'llvm::PointerIntPair<const clang::InitializedEntity *, 3, (anonymous namespace)::LifetimeKind, llvm::PointerLikeTypeTraits<const clang::InitializedEntity *>, llvm::PointerIntPairInfo<const clang::InitializedEntity *, 3, llvm::PointerLikeTypeTraits<const clang::InitializedEntity *> > >::setPointerAndInt' requested here
setPointerAndInt(PtrVal, IntVal);
^
llvm/tools/clang/lib/Sema/SemaInit.cpp:6237:12: note: in instantiation of member function 'llvm::PointerIntPair<const clang::InitializedEntity *, 3, (anonymous namespace)::LifetimeKind, llvm::PointerLikeTypeTraits<const clang::InitializedEntity *>, llvm::PointerIntPairInfo<const clang::InitializedEntity *, 3, llvm::PointerLikeTypeTraits<const clang::InitializedEntity *> > >::PointerIntPair' requested here
return {Entity, LK_Extended};
Full log here:
http://lab.llvm.org:8011/builders/clang-cmake-armv7-global-isel/builds/1330http://lab.llvm.org:8011/builders/clang-cmake-armv7-full/builds/1394
llvm-svn: 337255
This change implements C++ DR1696, which makes initialization of a
reference member of a class from a temporary object ill-formed. The
standard wording here is imprecise, but we interpret it as meaning that
any time a mem-initializer would result in lifetime extension, the
program is ill-formed.
llvm-svn: 337226
This allows more qualification conversions, eg. conversion from
'int *(*)[]' -> 'const int *const (*)[]'
is now permitted, along with all the consequences of that: more types
are similar, more cases are permitted by const_cast, and conversely,
fewer "casting away constness" cases are permitted by reinterpret_cast.
llvm-svn: 336745
layout" rules.
The new rules say that a standard-layout struct has its first non-static
data member and all base classes at offset 0, and consider a class to
not be standard-layout if that would result in multiple subobjects of a
single type having the same address.
We track "is C++11 standard-layout class" separately from "is
standard-layout class" so that the ABIs that need this information can
still use it.
Differential Revision: https://reviews.llvm.org/D45176
llvm-svn: 329332
More generally, this permits a template to be specialized in any scope in which
it could be defined, so this also supersedes DR44 and DR374 (the latter of
which we previously only implemented in C++11 mode onwards due to unclarity as
to whether it was a DR).
llvm-svn: 327705
While here, fix up the myriad other ways in which Sema's two "can this handler
catch that exception?" implementations get things wrong and unify them.
llvm-svn: 322431
Summary:
3.4.6 [basic.lookup.udir] paragraph 1:
In a using-directive or namespace-alias-definition, during the lookup for a namespace-name or for a name in a nested-name-specifier, only namespace names are considered.
Reviewers: rsmith, aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D30848
llvm-svn: 298126
Under this defect resolution, the injected-class-name of a class or class
template cannot be used except in very limited circumstances (when declaring a
constructor, in a nested-name-specifier, in a base-specifier, or in an
elaborated-type-specifier). This is apparently done to make parsing easier, but
it's a pain for us since we don't know whether a template-id using the
injected-class-name is valid at the point when we annotate it (we don't yet
know whether the template-id will become part of an elaborated-type-specifier).
As a tentative resolution to a perceived language defect, mem-initializer-ids
are added to the list of exceptions here (they generally follow the same rules
as base-specifiers).
When the reference to the injected-class-name uses the 'typename' or 'template'
keywords, we permit it to be used to name a type or template as an extension;
other compilers also accept some cases in this area. There are also a couple of
corner cases with dependent template names that we do not yet diagnose, but
which will also get this treatment.
llvm-svn: 292518
This rule permits the injected-class-name of a class template to be used as
both a template type argument and a template template argument, with no extra
syntax required to disambiguate.
llvm-svn: 292426
Diasllow a declaration using the 'auto' type specifier from using two different
meanings of it at once, or from declaring multiple functions with deduced
return types or introducing multiple trailing return types.
The standard does not technically disallow the multiple trailing return types
case if all the declarators declare variables (such as function pointers with
trailing return types), but we disallow that too, following the clear intent.
llvm-svn: 291880
* Update version number in DR tests from 4.0 to 4
* Teach make_cxx_dr_status script about version numbers that don't contain a
period.
* Update cxx_status.html and cxx_dr_status.html to list Clang 4 features as
"Clang 4" rather than "SVN"
Clang 4 features are still listed in yellow rather than green until release.
llvm-svn: 291871
Check for implicit conversion sequences for non-dependent function
template parameters between deduction and substitution. The idea is to accept
as many cases as possible, on the basis that substitution failure outside the
immediate context is much more common during substitution than during implicit
conversion sequence formation.
This re-commits r290808, reverted in r290811 and r291412, with a couple of
fixes for handling of explicitly-specified non-trailing template argument
packs.
llvm-svn: 291427