The old version of _Sp_counted_ptr_inplace::_M_get_deleter (up to GCC
8.2.0) expects to be passed a real std::typeinfo object, so mixing that
with the new definition of the __shared_ptr constructor (which always
passes the fake tag) leads to accessing the fake object as a real
std::typeinfo. Instead of trying to make it safe to mix the old and new
definitions, just stop using that function. By passing a reference to
__shared_ptr::_M_ptr to the __shared_count constructor it can be set
directly, without needing to obtain the pointer via the _M_get_deleter
back-channel. This avoids a virtual dispatch (which fixes PR 87514).
This means that code built against new libstdc++ headers doesn't use
_M_get_deleter at all, and so make_shared works the same whether RTTI is
enabled or not.
Also change _M_get_deleter so that it checks for a real type_info object
even when RTTI is disabled, by calling a library function. Unless
libstdc++ itself is built without RTTI that library function will be
able to test if it's the right type_info. This means the new definition
of _M_get_deleter can handle both the fake type_info tag and a real
type_info object, even if built without RTTI.
If linking to objects built against older versions of libstdc++ then if
all objects use -frtti or all use -fno-rtti, then the caller of
_M_get_deleter and the definition of _M_get_deleter will be consistent
and it will work. If mixing -frtti with -fno-rtti it can still fail if
the linker picks an old definition of _M_get_deleter and an old
__shared_ptr constructor that are incompatible. In that some or all
objects might need to be recompiled.
PR libstdc++/87514
PR libstdc++/87520
PR libstdc++/88782
* config/abi/pre/gnu.ver (GLIBCXX_3.4.26): Export new symbol.
* include/bits/shared_ptr.h
(shared_ptr(_Sp_make_shared_tag, const Alloc&, Args&&...))
(allocate_shared): Change to use new tag type.
* include/bits/shared_ptr_base.h (_Sp_make_shared_tag::_S_eq):
Declare new member function.
(_Sp_alloc_shared_tag): Define new type.
(_Sp_counted_ptr_inplace): Declare __shared_count<_Lp> as a friend.
(_Sp_counted_ptr_inplace::_M_get_deleter) [!__cpp_rtti]: Use
_Sp_make_shared_tag::_S_eq to check type_info.
(__shared_count(Ptr, Deleter),__shared_count(Ptr, Deleter, Alloc)):
Constrain to prevent being called with _Sp_alloc_shared_tag.
(__shared_count(_Sp_make_shared_tag, const _Alloc&, Args&&...)):
Replace constructor with ...
(__shared_count(Tp*&, _Sp_alloc_shared_tag<_Alloc>, Args&&...)): Use
reference parameter so address of the new object can be returned to
the caller. Obtain the allocator from the tag type.
(__shared_ptr(_Sp_make_shared_tag, const Alloc&, Args&&...)): Replace
constructor with ...
(__shared_ptr(_Sp_alloc_shared_tag<Alloc>, Args&&...)): Pass _M_ptr
to the __shared_count constructor.
(__allocate_shared): Change to use new tag type.
* src/c++11/shared_ptr.cc (_Sp_make_shared_tag::_S_eq): Define.
From-SVN: r268086
PR libstdc++/88738
Warn about unused comparisons of shared_ptr/unique_ptr
* include/bits/c++config [_GLIBCXX_NODISCARD]: Define.
* include/bits/shared_ptr.h: Use it for operator ==, !=,
<, <=, >, >= for shared_ptr.
* include/bits/unique_ptr.h: Likewise for unique_ptr.
From-SVN: r267964
This patch implements the C++2a proposal to allow incomplete types in
std::reference_wrapper, which was previously undefined.
The change cannot be implemented for earlier standards, because prior to
C++2a std::reference_wrapper has a weak result type, so must inspect the
template argument to see if it defines a nested result_type member. That
is deprecated (but still required) in C++17, and removed from C++2a.
The removal of the base class from reference_wrapper is a potential ABI
change, as it could alter the layout of a type which derives from
reference_wrapper<T> and from an empty type with _Weak_result_type<T> as
a base class. Previously the repeated _Weak_result_type<T> base class
would have prevented the empty base-class optimization, but if
reference_wrapper<T> no longer derives from it, the empty class could be
placed at the same address as the reference_wrapper<T> base. In
practice, the only types which derive from _Weak_result_type or from
_Reference_wrapper_base_memfun or any of its base classes are non-empty
types defined in libstdc++: std::reference_wrapper, std::function, and
std::_Bind. As they are non-empty types, they are not eligible for EBO
anyway.
* include/bits/refwrap.h [__cplusplus > 201703L]
(_Refwrap_base_arg1, _Refwrap_base_arg2, _Reference_wrapper_base)
(_Reference_wrapper_base_memfun): Do not define for C++2a.
(reference_wrapper): Do not derive from _Reference_wrapper_base_memfun
for C++2a.
(reference_wrapper::operator()): Add static assertion.
* testsuite/20_util/reference_wrapper/incomplete.cc: New test.
From-SVN: r267866
This paper has been included in the C++20 draft, but the changes to add
noexcept can be made unconditionally, to apply for C++11 too.
* include/std/chrono (duration_values::zero(), duration_values::min())
(duration_values::max()): Add noexcept.
(duration::zero(), duration::min(), duration::max()): Likewise.
(time_point::zero(), time_point::min(), time_point::max()): Likewise.
* testsuite/20_util/duration/requirements/noexcept.cc: New test.
* testsuite/20_util/time_point/requirements/noexcept.cc: New test.
From-SVN: r267865
The C++2a draft specifies the value 201811L for this, but as an
extension we return the number of elements erased. This is expected to
be standardised, so the macro has the value 201900L until a proper value
is specified in the draft.
* include/bits/erase_if.h: Define __cpp_lib_erase_if.
* include/std/deque: Likewise.
* include/std/forward_list: Likewise.
* include/std/list: Likewise.
* include/std/string: Likewise.
* include/std/vector: Likewise.
* include/std/version: Likewise.
* testsuite/21_strings/basic_string/erasure.cc: Test macro.
* testsuite/23_containers/deque/erasure.cc: Likewise.
* testsuite/23_containers/forward_list/erasure.cc: Likewise.
* testsuite/23_containers/list/erasure.cc: Likewise.
* testsuite/23_containers/map/erasure.cc: Likewise.
* testsuite/23_containers/set/erasure.cc: Likewise.
* testsuite/23_containers/unordered_map/erasure.cc: Likewise.
* testsuite/23_containers/unordered_set/erasure.cc: Likewise.
* testsuite/23_containers/vector/erasure.cc: Likewise.
From-SVN: r267810
The AI_NUMERICSERV constant is missing from old Darwin systems, so only
use it if it's supported.
* include/experimental/internet [AI_NUMERICSERV]
(resolver_base::numeric_service): Define conditionally.
* testsuite/experimental/net/internet/resolver/base.cc: Test it
conditionally.
* testsuite/experimental/net/internet/resolver/ops/lookup.cc:
Likewise.
From-SVN: r267809
2019-01-10 Ville Voutilainen <ville.voutilainen@gmail.com>
Jonathan Wakely <jwakely@redhat.com>
Implement LWG 2221
* config/abi/pre/gnu.ver (GLIBCXX_3.4): Tighten patterns.
(GLIBCXX_3.4.26): Add new exports.
* include/Makefile.am: Add ostream-inst.cc. Move string-inst.cc to
correct list of sources.
* include/Makefile.in: Regenerate.
* include/std/ostream (operator<<(nullptr_t)): New member function.
* src/c++17/ostream-inst.cc: New file.
* testsuite/27_io/basic_ostream/inserters_other/char/lwg2221.cc: New
test.
Co-Authored-By: Jonathan Wakely <jwakely@redhat.com>
From-SVN: r267808
PR tree-optimization/88775
* include/bits/stl_function.h (greater<_Tp*>::operator(),
less<_Tp*>::operator(), greater_equal<_Tp*>::operator(),
less_equal<_Tp*>::operator()): Use __builtin_is_constant_evaluated
instead of __builtin_constant_p if available. Don't bother with
the pointer comparison in C++11 and earlier.
From-SVN: r267800
Hoist the duplicated code from the _Optional_payload partial
specializations into the _Optional_payload_base base class.
* include/std/optional (_Optional_payload_base::_M_copy_assign): New
member function to perform non-trivial assignment.
(_Optional_payload_base::_M_move_assign): Likewise.
(_Optional_payload<T, true, false, true>::operator=)
(_Optional_payload<T, true, true, false>::operator=)
(_Optional_payload<T, true, false, false>::operator=): Call
_M_copy_assign and/or _M_move_assign to do non-trivial assignments.
From-SVN: r267761
When the contained value is not trivially copy (or move) constructible
the union's copy (or move) constructor will be deleted, and so the
_Optional_payload delegating constructors are invalid. G++ fails to
diagnose this because it incorrectly performs copy elision in the
delegating constructors. Clang does diagnose it (llvm.org/PR40245).
The solution is to avoid performing any copy (or move) when the
contained value's copy (or move) constructor isn't trivial. Instead the
contained value can be constructed by calling _M_construct. This is OK,
because the relevant constructor doesn't need to be constexpr when the
contained value isn't trivially copy (or move) constructible.
Additionally, this patch removes a lot of code duplication in the
_Optional_payload partial specializations and the _Optional_base partial
specialization, by hoisting it into common base classes.
The Python pretty printer for std::optional needs to be adjusted to
support the new layout. Retain support for the old layout, and add a
test to verify that the support still works.
PR libstdc++/87855
* include/std/optional (_Optional_payload_base): New class template
for common code hoisted from _Optional_payload specializations. Use
a template for the union, to allow a partial specialization for
types with non-trivial destructors. Add constructors for in-place
initialization to the union.
(_Optional_payload(bool, const _Optional_payload&)): Use _M_construct
to perform non-trivial copy construction, instead of relying on
non-standard copy elision in a delegating constructor.
(_Optional_payload(bool, _Optional_payload&&)): Likewise for
non-trivial move construction.
(_Optional_payload): Derive from _Optional_payload_base and use it
for everything except the non-trivial assignment operators, which are
defined as needed.
(_Optional_payload<false, C, M>): Derive from the specialization
_Optional_payload<true, false, false> and add a destructor.
(_Optional_base_impl::_M_destruct, _Optional_base_impl::_M_reset):
Forward to corresponding members of _Optional_payload.
(_Optional_base_impl::_M_is_engaged, _Optional_base_impl::_M_get):
Hoist common members from _Optional_base.
(_Optional_base): Make all members and base class public.
(_Optional_base::_M_get, _Optional_base::_M_is_engaged): Move to
_Optional_base_impl.
* python/libstdcxx/v6/printers.py (StdExpOptionalPrinter): Add
support for new std::optional layout.
* testsuite/libstdc++-prettyprinters/compat.cc: New test.
From-SVN: r267742
Using #include "..." to include a header in the same directory fails if
the user compiles with -I-, so always use something like <bits/...> for
internal headers.
I haven't added tests for this, because dg-options adds options to the
end, and the position of -I- matters (if it's at the end then the tests
won't find any headers in the build tree, as they're specified by -I
options earlier in the flags). It's been manually tested though.
PR libstdc++/88066
* include/bits/locale_conv.h: Use <> for includes not "".
* include/ext/random: Likewise.
* include/ext/vstring.h: Likewise.
From-SVN: r267726
The C++ char_traits and ctype APIs do not disallow null pointer
arguments, so we need explicit checks to ensure we don't forward null
pointers to memcpy or memmove.
PR libstdc++/87787
* include/bits/char_traits.h (char_traits::move): Do not pass null
pointers to memmove.
* include/bits/locale_facets.h
(ctype<char>::widen(const char*, const char*, char*)): Do not
pass null pointers to memcpy.
(ctype<char>::narrow(const char*, const char*, char, char*)):
Likewise.
(ctype<char>::do_widen(const char*, const char*, char*)):
Likewise.
(ctype<char>::do_narrow(const char*, const char*, char, char*)):
Likewise.
From-SVN: r267651
The previous patch for PR 87431 assumed that initialing a scalar type
could not throw, but it can obtain its value via a conversion operator,
which could throw. This meant the variant could get into a valueless
state, but the valueless_by_exception() member function would always
return false.
This patch fixes it by changing the emplace members to have strong
exception safety when initializing a contained value of trivially
copyable type. The _M_valid() member gets a corresponding change to
always return true for trivially copyable types, not just scalar types.
Strong exception safety (i.e. never becoming valueless) is achieved by
only replacing the current contained value once any potentially throwing
operations have completed. If constructing the new contained value can
throw then a new std::variant object is constructed to hold it, and then
move-assigned to *this (which won't throw).
PR libstdc++/87431
* include/std/variant (_Variant_storage<true, _Types...>::_M_valid):
Check is_trivially_copyable instead of is_scalar.
(variant::emplace<N, Args>(Args&&...)): If construction of the new
contained value can throw and its type is trivially copyable then
construct into a temporary variant and move from it, to provide the
strong exception safety guarantee.
(variant::emplace<N, U, Args>(initializer_list<U>, Args&&...)):
Likewise.
* testsuite/20_util/variant/87431.cc: New test.
* testsuite/20_util/variant/run.cc: Adjust test so that throwing
conversion causes valueless state.
From-SVN: r267614
In C++17 the clock used for filesystem::file_time_type is unspecified,
allowing it to be chrono::system_clock. The C++2a draft requires it to
be a distinct type, with additional member functions to convert to/from
other clocks (either the system clock or UTC). In order to avoid an ABI
change later, this patch defines a new distinct type now, which will be
used for std::chrono::file_clock later.
* include/bits/fs_fwd.h (__file_clock): Define new clock.
(file_time_type): Redefine in terms of __file_clock.
* src/filesystem/ops-common.h (file_time): Add FIXME comment about
overflow.
* src/filesystem/std-ops.cc (is_set(perm_options, perm_options)): Give
internal linkage.
(internal_file_lock): New helper type for accessing __file_clock.
(do_copy_file): Use internal_file_lock to convert system time to
file_time_type.
(last_write_time(const path&, error_code&)): Likewise.
(last_write_time(const path&, file_time_type, error_code&)): Likewise.
From-SVN: r267602
The C++17 standard added some new members to std::basic_string, which
were not previously instantiated in the library. This meant that the
extern template declarations had to be disabled for C++17 mode. With
this patch the new members are instantiated in the library and so the
explicit instantiation declarations can be used for C++17.
The new members added by C++2a are still not exported, and so the
explicit instantiation declarations are still disabled for C++2a.
* config/abi/pre/gnu.ver (GLIBCXX_3.4.21): Make patterns less greedy
for const member functions of std::basic_string.
(GLIBCXX_3.4.26): Export member functions of std::basic_string added
in C++17.
* include/bits/basic_string.h (basic_string(__sv_wrapper, const A&)):
Make non-standard constructor private.
[!_GLIBCXX_USE_CXX11_ABI] (basic_string(__sv_wrapper, const A&)):
Likewise.
* include/bits/basic_string.tcc (std::string, std::wstring): Declare
explicit instantiations for C++17 as well as earlier dialects.
* src/c++17/Makefile.am: Add new source files.
* src/c++17/Makefile.in: Regenerate.
* src/c++17/cow-string-inst.cc: New file defining explicit
instantiations for basic_string member functions added in C++17.
* src/c++17/string-inst.cc: Likewise.
From-SVN: r267585
Add these constructors from C++11 which were missing from the COW
basic_string. Additionally simplify the definitions of the
basic_string::reference and basic_string::const_reference types as
required by C++11.
This allows filesystem::path::string<Allocator>() to be simplified, so
that the same code is used for both basic_string implementations.
* config/abi/pre/gnu.ver (GLIBCXX_3.4.26): Export allocator-extended
copy/move constructors for old std::basic_string.
* include/bits/basic_string.h [!_GLIBCXX_USE_CXX11_ABI]
(basic_string::reference, basic_string::const_reference): Define
as plain references for C++11 and later.
(basic_string::basic_string()): Put constructor body outside
preprocessor conditional groups.
(basic_string::basic_string(basic_string&&)): Move _Alloc_hider
instead of copying it.
(basic_string::basic_string(const basic_string&, const _Alloc&)):
Define.
(basic_string::basic_string(basic_string&&, const _Alloc&)):
Define.
* include/bits/fs_path.h [!_GLIBCXX_USE_CXX11_ABI]: Remove special
cases for old basic_string.
* testsuite/21_strings/basic_string/cons/char/8.cc: Test
allocator-extended constructors unconditionally. Add extra members to
allocator type when using old string ABI.
* testsuite/21_strings/basic_string/allocator/71964.cc: Enable test
for old string ABI.
* testsuite/21_strings/basic_string/cons/wchar_t/8.cc: Likewise.
From-SVN: r267584
Using path::_List::erase(const_iterator) to remove a non-final component
in path::lexically_normal() is a bug, because it leaves the following
component with an incorrect _M_pos value.
Instead of providing erase members that allow removing components from
the middle, replace them with pop_back() and
_M_erase_from(const_iterator) which only allow removing elements at the
end. Most uses of erase are unaffected, because they only remove
elements from the end anyway. The one use of erasure from the middle in
lexically_normal() is replaced by calls to pop_back() and/or clearing
the last component to leave it as an empty final filename.
Also replace the "???" comment in lexically_normal() to document when
that branch is taken.
* include/bits/fs_path.h (path::_List::erase): Replace both overloads
with ...
(path::pop_back(), path::_M_erase_from(const_iterator)): New member
functions that will only erase elements at the end.
* src/filesystem/std-path.cc (path::_List::_Impl::pop_back()): Define.
(path::_List::_Impl::_M_erase_from(const_iterator)): Define.
(path::_List::operator=(const _List&)): Use _M_erase_from(p) instead
of erase(p, end()).
(path::_List::pop_back()): Define.
(path::_List::_M_erase_from(const_iterator)): Define.
(path::operator/=(const path&)): Use pop_back to remove last component
and _M_erase_from to remove multiple components.
(path::_M_append(basic_string_view<value_type>)): Likewise.
(path::operator+=(const path&)): Likewise.
(path::_M_concat(basic_string_view<value_type>)): Likewise.
(path::remove_filename()): Likewise.
(path::lexically_normal()): Use _List::_Impl iterators instead of
path::iterator. Use pop_back to remove components from the end. Clear
trailing filename, instead of using erase(const_iterator) to remove
a non-final component.
* testsuite/27_io/filesystem/path/generation/normal.cc: Test
additional cases.
* testsuite/27_io/filesystem/path/generation/normal2.cc: New test.
From-SVN: r267576
There are a number of UTF-8 characters in comments which add no value
and can be replaced with ASCII equivalents, or removed entirely for the
section sign (U+00A7).
PR libstdc++/88607
* include/bits/forward_list.h: Replace UTF-8 "ligature fi" character.
* include/debug/forward_list: Likewise.
* include/experimental/bits/shared_ptr.h: Remove UTF-8 "section sign"
character.
* include/experimental/chrono: Likewise.
* include/experimental/functional: Likewise.
* include/experimental/ratio: Likewise.
* include/experimental/system_error: Likewise.
* include/experimental/tuple: Likewise.
* include/experimental/type_traits: Likewise.
* include/parallel/workstealing.h: Replace UTF-8 "en dash" character.
* include/parallel/multiseq_selection.h: Likewise.
From-SVN: r267564
* include/bits/fs_dir.h (operator<<): Overload for directory_entry,
as per LWG 3171.
* testsuite/27_io/filesystem/directory_entry/lwg3171.cc: New test.
From-SVN: r267238
The resolution for LWG 2936 defines the comparison more precisely, which
this patch implements. The patch also defines comparisons with strings
to work without constructing a temporary path object (so avoids any
memory allocations).
* include/bits/fs_path.h (path::compare(const string_type&))
(path::compare(const value_type*)): Add noexcept and construct a
string view to compare to instead of a path.
(path::compare(basic_string_view<value_type>)): Add noexcept. Remove
inline definition.
* src/filesystem/std-path.cc (path::_Parser): Track last type read
from input.
(path::_Parser::next()): Return a final empty component when the
input ends in a non-root directory separator.
(path::_M_append(basic_string_view<value_type>)): Remove special cases
for trailing non-root directory separator.
(path::_M_concat(basic_string_view<value_type>)): Likewise.
(path::compare(const path&)): Implement LWG 2936.
(path::compare(basic_string_view<value_type>)): Define in terms of
components returned by parser, consistent with LWG 2936.
* testsuite/27_io/filesystem/path/compare/lwg2936.cc: New.
* testsuite/27_io/filesystem/path/compare/path.cc: Test more cases.
* testsuite/27_io/filesystem/path/compare/strings.cc: Likewise.
From-SVN: r267235
* include/std/string_view [__cplusplus > 201703L]
(basic_string_view::starts_with(basic_string_view)): Implement
proposed resolution of LWG 3040 to avoid redundant length check.
(basic_string_view::starts_with(_CharT)): Implement proposed
resolution of LWG 3040 to check at most one character.
(basic_string_view::ends_with(_CharT)): Likewise.
From-SVN: r267234
This new implementation has a smaller footprint than the previous
implementation, due to replacing std::vector<_Cmpt> with a custom pimpl
type that only needs a single pointer. The _M_type enumeration is also
combined with the pimpl type, by using a tagged pointer, reducing
sizeof(path) further still.
Construction and modification of paths is now done more efficiently, by
splitting the input into a stack-based buffer of string_view objects
instead of a dynamically-allocated vector containing strings. Once the
final size is known only a single allocation is needed to reserve space
for it. The append and concat operations no longer require constructing
temporary path objects, nor re-parsing the entire native pathname.
This results in algorithmic improvements to path construction, and
working with large paths is much faster.
PR libstdc++/71044
* include/bits/fs_path.h (path::path(path&&)): Add noexcept when
appropriate. Move _M_cmpts instead of reparsing the native pathname.
(path::operator=(const path&)): Do not define as defaulted.
(path::operator/=, path::append): Call _M_append.
(path::concat): Call _M_concat.
(path::path(string_type, _Type): Change type of first parameter to
basic_string_view<value_type>.
(path::_M_append(basic_string_view<value_type>)): New member function.
(path::_M_concat(basic_string_view<value_type>)): New member function.
(_S_convert(value_type*, __null_terminated)): Return string view.
(_S_convert(const value_type*, __null_terminated)): Return string view.
(_S_convert(value_type*, value_type*))
(_S_convert(const value_type*, const value_type*)): Add overloads for
pairs of pointers.
(_S_convert(_InputIterator, __null_terminated)): Construct string_type
explicitly, for cases where _S_convert returns a string view.
(path::_S_is_dir_sep): Replace with non-member is_dir_sep.
(path::_M_trim, path::_M_add_root_name, path::_M_add_root_dir)
(path::_M_add_filename): Remove.
(path::_M_type()): New member function to replace _M_type data member.
(path::_List): Define new struct type instead of using std::vector.
(path::_Cmpt::_Cmpt(string_type, _Type, size_t)): Change type of
first parameter to basic_string_view<value_type>.
(path::operator+=(const path&)): Do not define inline.
(path::operator+=(const string_type&)): Call _M_concat.
(path::operator+=(const value_type*)): Likewise.
(path::operator+=(value_type)): Likewise.
(path::operator+=(basic_string_view<value_type>)): Likewise.
(path::operator/=(const path&)): Do not define inline.
(path::_M_append(path)): Remove.
* python/libstdcxx/v6/printers.py (StdPathPrinter): New printer that
understands the new path::_List type.
* src/filesystem/std-path.cc (is_dir_sep): New function to replace
path::_S_is_dir_sep.
(path::_Parser): New helper class to parse strings as paths.
(path::_List::_Impl): Define container type for path components.
(path::_List): Define members.
(path::operator=(const path&)): Define explicitly, to provide the
strong exception safety guarantee.
(path::operator/=(const path&)): Implement manually by processing
each component of the argument, rather than using _M_split_cmpts
to parse the entire string again.
(path::_M_append(string_type)): Likewise.
(path::operator+=(const path&)): Likewise.
(path::_M_concat(string_type)): Likewise.
(path::remove_filename()): Perform trim directly instead of calling
_M_trim().
(path::_M_split_cmpts()): Rewrite in terms of _Parser class.
(path::_M_trim, path::_M_add_root_name, path::_M_add_root_dir)
(path::_M_add_filename): Remove.
* testsuite/27_io/filesystem/path/append/source.cc: Test appending a
string view that aliases the path.
testsuite/27_io/filesystem/path/concat/strings.cc: Test concatenating
a string view that aliases the path.
From-SVN: r267106
Although filesystem::path::iterator is only a bidirectional iterator,
the underlying sequence has random access iterators (specifically, raw
pointers). This means std::distance and std::advance can be implemented
more efficiently than the generic versions which apply ++ and --
repeatedly.
PR libstdc++/71044 (partial)
* include/bits/fs_path.h (__path_iter_distance, __path_iter_advance):
New friend functions to implement std::distance and std::advance more
efficiently.
(distance, advance): Add overloads for path::iterator.
* testsuite/27_io/filesystem/path/itr/components.cc: Test new
overload.
From-SVN: r267057
Ensure we don't try to instantiate __is_constructible_from<void, void>,
because there are two partial specializations that are equally good
matches.
PR libstdc++/80762
* include/bits/fs_path.h (path::_Path): Use remove_cv_t and is_void.
* include/experimental/bits/fs_path.h (path::_Path): Likewise.
* testsuite/27_io/filesystem/path/construct/80762.cc: New test.
* testsuite/experimental/filesystem/path/construct/80762.cc: New test.
From-SVN: r267056
2018-11-29 Edward Smith-Rowland <3dw4rd@verizon.net>
Only include bits/stl_algo.h for C++20.
* include/std/deque: Only include bits/stl_algo.h for C++20.
* include/std/string: Ditto.
* include/std/vector: Ditto.
From-SVN: r266624
Now that __alignof__ and alignof sometimes disagree it matters which one
we use. The standard says that std::alignment_of<T>::value equals
alignof(T), so we need to use that.
Change the only uses of alignment_of to use __alignof__ to avoid a
change in alignment.
PR libstdc++/88119
* include/ext/aligned_buffer.h (__aligned_membuf): Add comment.
(__aligned_buffer): Use __alignof__ instead of std::alignment_of.
* include/std/type_traits (alignment_of): Use alignof instead of
__alignof__.
* testsuite/20_util/alignment_of/value.cc: Fix test to check values
match alignof not __alignof__, as required by the standard.
From-SVN: r266613
The class API provides no way to modify the members, so we can share
them between copies of the same object. Copying becomes a simple
reference count update, which doesn't throw.
Also adjust the what() string to allow distinguishing between an empty
path passed to the constructor, and no path.
PR libstdc++/83306
* include/bits/fs_path.h (filesystem_error): Move data members into
pimpl class owned by shared_ptr. Remove inline definitions of member
functions.
* src/filesystem/std-path.cc (filesystem_error::_Impl): Define.
(filesystem_error): Define member functions.
* testsuite/27_io/filesystem/filesystem_error/cons.cc: New test.
* testsuite/27_io/filesystem/filesystem_error/copy.cc: New test.
From-SVN: r266565
This resolves a longstanding issue where the lock policy for shared_ptr
reference counting depends on compilation options when the header is
included, so that different -march options can cause ABI changes. For
example, objects compiled with -march=armv7 will use atomics to
synchronize reference counts, and objects compiled with -march=armv5t
will use a mutex. That means the shared_ptr control block will have a
different layout in different objects, causing ODR violations and
undefined behaviour. This was the root cause of PR libstdc++/42734 as
well as PR libstdc++/67843.
The solution is to decide on the lock policy at build time, when
libstdc++ is configured. The configure script checks for the
availability of the necessary atomic built-ins for the target and fixes
that choice permanently. Different -march flags used to compile user
code will not cause changes to the lock policy. This results in an ABI
change for certain compilations, but only where there was already an ABI
incompatibility between the libstdc++.so library and objects built with
an incompatible -march option. In general, this means a more stable ABI
that isn't silently altered when -march flags make addition atomic ops
available.
To force a target to use "atomic" or "mutex" the new configure option
--with-libstdcxx-lock-policy can be used.
In order to turn ODR violations into linker errors, the uses of
shared_ptr in filesystem directory iterators have been replaced
with __shared_ptr, and explicit instantiations are declared. This
ensures that object files using those types cannot link to libstdc++
libs unless they use the same lock policy.
PR libstdc++/67843
* acinclude.m4 (GLIBCXX_ENABLE_LOCK_POLICY): Add new macro
that defines _GLIBCXX_HAVE_ATOMIC_LOCK_POLICY.
* config.h.in: Regenerate.
* configure: Regenerate.
* configure.ac: Use GLIBCXX_ENABLE_LOCK_POLICY.
* doc/xml/manual/configure.xml: Document new configure option.
* include/bits/fs_dir.h (directory_iterator): Use __shared_ptr
instead of shared_ptr.
(recursive_directory_iterator): Likewise.
(__shared_ptr<_Dir>): Add explicit instantiation declaration.
(__shared_ptr<recursive_directory_iterator::_Dir_stack>): Likewise.
* include/bits/shared_ptr_base.h (__allocate_shared, __make_shared):
Add default template argument for _Lock_policy template parameter.
* include/ext/concurrence.h (__default_lock_policy): Check macro
_GLIBCXX_HAVE_ATOMIC_LOCK_POLICY instead of checking if the current
target supports the builtins for compare-and-swap.
* src/filesystem/std-dir.cc (__shared_ptr<_Dir>): Add explicit
instantiation definition.
(__shared_ptr<recursive_directory_iterator::_Dir_stack>): Likewise.
(directory_iterator, recursive_directory_iterator): Use __make_shared
instead of make_shared.
From-SVN: r266533
Jakub Jelinek
Ulrich Drepper
Jonathan Wakely
Jakub Jelinek
Ville Voutilainen
Sandra Loosemore
François Dumont
Edward Smith-Rowland
Edward Smith-Rowland