libstdc++-v3/ChangeLog:
* include/debug/assertions.h (__glibcxx_requires_non_empty_range):
Remove __builtin_expect.
(__glibcxx_requires_subscript): Likewise.
(__glibcxx_requires_nonempty): Likewise.
* include/debug/formatter.h (__check_singular): Add C++11 constexpr
qualification.
* include/debug/helper_functions.h (__check_singular): Likewise. Skip
check if constant evaluated.
(__valid_range): Do not skip check if constant evaluated.
* include/debug/macros.h (_GLIBCXX_DEBUG_VERIFY_COND_AT): Add
__builtin_expect.
(_GLIBCXX_DEBUG_VERIFY_AT_F): Use __glibcxx_assert_1.
* testsuite/21_strings/basic_string_view/element_access/char/back_constexpr_neg.cc:
New test.
* testsuite/21_strings/basic_string_view/element_access/char/constexpr.cc: New test.
* testsuite/21_strings/basic_string_view/element_access/char/constexpr_neg.cc: New test.
* testsuite/21_strings/basic_string_view/element_access/char/front_back_constexpr.cc:
New test.
* testsuite/21_strings/basic_string_view/element_access/char/front_constexpr_neg.cc:
New test.
* testsuite/21_strings/basic_string_view/element_access/wchar_t/back_constexpr_neg.cc:
New test.
* testsuite/21_strings/basic_string_view/element_access/wchar_t/constexpr.cc: New test.
* testsuite/21_strings/basic_string_view/element_access/wchar_t/constexpr_neg.cc: New test.
* testsuite/21_strings/basic_string_view/element_access/wchar_t/front_constexpr_neg.cc:
New test.
* testsuite/25_algorithms/lower_bound/debug/constexpr_partitioned_neg.cc: New test.
* testsuite/25_algorithms/lower_bound/debug/constexpr_partitioned_pred_neg.cc: New test.
* testsuite/25_algorithms/lower_bound/debug/constexpr_valid_range_neg.cc: New test.
* testsuite/25_algorithms/lower_bound/debug/partitioned_neg.cc: New test.
* testsuite/25_algorithms/lower_bound/debug/partitioned_pred_neg.cc: New test.
* testsuite/25_algorithms/upper_bound/debug/constexpr_partitioned_neg.cc: New test.
* testsuite/25_algorithms/upper_bound/debug/constexpr_partitioned_pred_neg.cc: New test.
* testsuite/25_algorithms/upper_bound/debug/constexpr_valid_range_neg.cc: New test.
* testsuite/25_algorithms/upper_bound/debug/partitioned_neg.cc: New test.
* testsuite/25_algorithms/upper_bound/debug/partitioned_pred_neg.cc: New test.
The popcount built-ins work fine for zero, so there's no need to check
for it.
libstdc++-v3/ChangeLog:
* include/std/bit (__popcount): Remove redundant check for zero.
With PR c++/67453 fixed we can rely on the 'used' attribute to emit
inline constructors and destructors in libsupc++/eh_ptr.cc. This means
we don't need to suppress the 'inline' keyword on them in that file, and
don't need to force 'always_inline' on them in other files.
libstdc++-v3/ChangeLog:
PR libstdc++/97729
* libsupc++/exception_ptr.h (exception_ptr::exception_ptr())
(exception_ptr::exception_ptr(const exception_ptr&))
(exception_ptr::~exception_ptr()): Remove 'always_inline'
attributes. Use 'inline' unconditionally.
The std::function code now uses std::type_info* even when RTTI is
disabled, so it should include <typeinfo> unconditionally. Without this,
Clang can't compile <functional> with -fno-rtti (it works with GCC
because std::type_info gets declared automatically by the compiler).
libstdc++-v3/ChangeLog:
PR libstdc++/97758
* include/bits/std_function.h [!__cpp_rtti]: Include <typeinfo>.
The mingw-w64 implementations of `__cxa_thread_atexit()` and `__cxa_atexit()` have been
using `__thiscall` since two years ago. Using the default calling convention (which is
`__cdecl`) causes crashes as explained in PR83562.
Calling conventions have no effect on x86_64-w64-mingw32.
Reference: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83562
Reference: https://sourceforge.net/p/mingw-w64/mingw-w64/ci/master/tree/mingw-w64-crt/crt/cxa_thread_atexit.c
Reference: f3e0fbb40c/
Reference: https://github.com/msys2/MINGW-packages/issues/7071
Signed-off-by: Liu Hao <lh_mouse@126.com>
2020-10-08 Liu Hao <lh_mouse@126.com>
libstdc++-v3:
* libsupc++/cxxabi.h: (__cxa_atexit): mark with _GLIBCXX_CDTOR_CALLABI
(__cxa_thread_atexit): ditto
* libsupc++/atexit_thread.cc: (__cxa_atexit): mark with
_GLIBCXX_CDTOR_CALLABI
(__cxa_thread_atexit): ditto
(elt): ditto
The change in r11-4748-50b840ac5e1d6534e345c3fee9a97ae45ced6bc7 causes
a build error on Solaris, due to the new explicit instantiation matching
patterns for two different symbol versions.
libstdc++-v3/ChangeLog:
* config/abi/pre/gnu.ver (GLIBCXX_3.4.21): Tighten up patterns
for basic_stringbuf that refer to __xfer_bufptrs.
This patch implements the -Wvexing-parse warning to warn about the
sneaky most vexing parse rule in C++: the cases when a declaration
looks like a variable definition, but the C++ language requires it
to be interpreted as a function declaration. This warning is on by
default (like clang++). From the docs:
void f(double a) {
int i(); // extern int i (void);
int n(int(a)); // extern int n (int);
}
Another example:
struct S { S(int); };
void f(double a) {
S x(int(a)); // extern struct S x (int);
S y(int()); // extern struct S y (int (*) (void));
S z(); // extern struct S z (void);
}
You can find more on this in [dcl.ambig.res].
I spent a fair amount of time on fix-it hints so that GCC can recommend
various ways to resolve such an ambiguity. Sometimes that's tricky.
E.g., suggesting default-initialization when the class doesn't have
a default constructor would not be optimal. Suggesting {}-init is also
not trivial because it can use an initializer-list constructor if no
default constructor is available (which ()-init wouldn't do). And of
course, pre-C++11, we shouldn't be recommending {}-init at all.
I also uncovered a bug in cp_parser_declarator, where we were setting
*parenthesized_p to true despite the comment saying the exact opposite.
gcc/c-family/ChangeLog:
PR c++/25814
* c.opt (Wvexing-parse): New option.
gcc/cp/ChangeLog:
PR c++/25814
* cp-tree.h (enum cp_tree_index): Add CPTI_EXPLICIT_VOID_LIST.
(explicit_void_list_node): Define.
(PARENTHESIZED_LIST_P): New macro.
(struct cp_declarator): Add function::parens_loc.
* decl.c (cxx_init_decl_processing): Initialize explicit_void_list_node.
(grokparms): Also break when explicit_void_list_node.
* parser.c (make_call_declarator): New location_t parameter. Use it
to set declarator->u.function.parens_loc.
(cp_parser_lambda_declarator_opt): Pass UNKNOWN_LOCATION to
make_call_declarator.
(warn_about_ambiguous_parse): New function.
(cp_parser_init_declarator): Call warn_about_ambiguous_parse.
(cp_parser_declarator): Set *parenthesized_p to false rather than to
true.
(cp_parser_direct_declarator): Create a location for the function's
parentheses and pass it to make_call_declarator.
(cp_parser_parameter_declaration_clause): Return explicit_void_list_node
for (void).
(cp_parser_parameter_declaration_list): Set PARENTHESIZED_LIST_P
in the parameters tree.
gcc/ChangeLog:
PR c++/25814
* doc/invoke.texi: Document -Wvexing-parse.
gcc/testsuite/ChangeLog:
PR c++/25814
* g++.dg/cpp2a/fn-template16.C: Add a dg-warning.
* g++.dg/cpp2a/fn-template7.C: Likewise.
* g++.dg/lookup/pr80891-5.C: Likewise.
* g++.dg/lto/pr79050_0.C: Add extern.
* g++.dg/lto/pr84805_0.C: Likewise.
* g++.dg/parse/pr58898.C: Add a dg-warning.
* g++.dg/template/scope5.C: Likewise.
* g++.old-deja/g++.brendan/recurse.C: Likewise.
* g++.old-deja/g++.jason/template4.C: Likewise.
* g++.old-deja/g++.law/arm4.C: Likewise.
* g++.old-deja/g++.mike/for2.C: Likewise.
* g++.old-deja/g++.other/local4.C: Likewise.
* g++.old-deja/g++.pt/crash3.C: Likewise.
* g++.dg/warn/Wvexing-parse.C: New test.
* g++.dg/warn/Wvexing-parse2.C: New test.
* g++.dg/warn/Wvexing-parse3.C: New test.
* g++.dg/warn/Wvexing-parse4.C: New test.
* g++.dg/warn/Wvexing-parse5.C: New test.
* g++.dg/warn/Wvexing-parse6.C: New test.
* g++.dg/warn/Wvexing-parse7.C: New test.
libstdc++-v3/ChangeLog:
PR c++/25814
* testsuite/20_util/reference_wrapper/lwg2993.cc: Add a dg-warning.
* testsuite/25_algorithms/generate_n/87982_neg.cc: Likewise.
The relational operators for std::optional were using the wrong types
in the declval expressions used to constrain them. Instead of using
const lvalues they were using non-const rvalues, which meant that a type
might satisfy the constraints but then give an error when the function
body was instantiated.
libstdc++-v3/ChangeLog:
PR libstdc++/96269
* include/std/optional (operator==, operator!=, operator<)
(operator>, operator<=, operator>=): Fix types used in
SFINAE constraints.
* testsuite/20_util/optional/relops/96269.cc: New test.
As described in the PR, the recursive_directory_iterator constructor
calls advance(ec), but ec is a pointer so it calls _Dir::advance(bool).
The intention was to either call advance() or advance(*ec) depending
whether the pointer is null or not.
This fixes the bug and renames the parameter to ecptr to make similar
mistakes less likely in future.
libstdc++-v3/ChangeLog:
PR libstdc++/97731
* src/filesystem/dir.cc (recursive_directory_iterator): Call the
right overload of _Dir::advance.
* testsuite/experimental/filesystem/iterators/97731.cc: New test.
This fixes some multiple definition errors caused by the changes for
PR libstdc++/90295. The previous solution for inlining the members of
std::exception_ptr but still exporting them from the library was to
suppress the 'inline' keyword on those functions when compiling
libsupc++/eh_ptr.cc, so they get defined in that file. That produces ODR
violations though, because there are now both inline and non-inline
definitions in the library, due to the use of std::exception_ptr in
other files sucg as src/c++11/future.cc.
The new solution is to define all the relevant members as 'inline'
unconditionally, but use __attribute__((used)) to cause definitions to
be emitted in libsupc++/eh_ptr.cc as before. This doesn't quite work
however, because PR c++/67453 means the attribute is ignored on
constructors and destructors. As a workaround, the old solution
(conditionally inline) is still used for those members, but they are
given the always_inline attribute so that they aren't emitted in
src/c++11/future.o as inline definitions.
libstdc++-v3/ChangeLog:
PR libstdc++/97729
* include/std/future (__basic_future::_M_get_result): Use
nullptr for null pointer constant.
* libsupc++/eh_ptr.cc (operator==, operator!=): Remove
definitions.
* libsupc++/exception_ptr.h (_GLIBCXX_EH_PTR_USED): Define
macro to conditionally add __attribute__((__used__)).
(operator==, operator!=, exception_ptr::exception_ptr())
(exception_ptr::exception_ptr(const exception_ptr&))
(exception_ptr::~exception_ptr())
(exception_ptr::operator=(const exception_ptr&))
(exception_ptr::swap(exception_ptr&)): Always define as
inline. Add macro to be conditionally "used".
- Add a missing 'explicit' to a basic_stringbuf constructor.
- Set up the get/put area pointers in the constructor from strings using
different allocator types.
- Remove public basic_stringbuf::__sv_type alias.
- Do not construct temporary basic_string objects with a
default-constructed allocator.
Also, change which basic_string constructor is used, as a minor
compile-time optimization. Constructing from a basic_string_view
requires more work from the compiler, so just use a pointer and length.
libstdc++-v3/ChangeLog:
* include/std/sstream (basic_stringbuf(const allocator_type&):
Add explicit.
(basic_stringbuf(const basic_string<C,T,SA>&, openmode, const A&)):
Call _M_stringbuf_init. Construct _M_string from pointer and length
to avoid constraint checks for string view.
(basic_stringbuf::view()): Make __sv_type alias local to the
function.
(basic_istringstream(const basic_string<C,T,SA>&, openmode, const A&)):
Pass string to _M_streambuf instead of constructing a temporary
with the wrong allocator.
(basic_ostringstream(const basic_string<C,T,SA>&, openmode, const A&)):
Likewise.
(basic_stringstream(const basic_string<C,T,SA>&, openmode, const A&)):
Likewise.
* src/c++20/sstream-inst.cc: Use string_view and wstring_view
typedefs in explicit instantiations.
* testsuite/27_io/basic_istringstream/cons/char/1.cc: Add more
tests for constructors.
* testsuite/27_io/basic_ostringstream/cons/char/1.cc: Likewise.
* testsuite/27_io/basic_stringbuf/cons/char/1.cc: Likewise.
* testsuite/27_io/basic_stringbuf/cons/char/2.cc: Likewise.
* testsuite/27_io/basic_stringbuf/cons/wchar_t/1.cc: Likewise.
* testsuite/27_io/basic_stringbuf/cons/wchar_t/2.cc: Likewise.
* testsuite/27_io/basic_stringstream/cons/char/1.cc: Likewise.
As noted in PR 96817 this new test fails if the library is built without
futexes. That's expected of course, but we might as well fail more
obviously than a deadlock that eventually times out.
libstdc++-v3/ChangeLog:
* testsuite/18_support/96817.cc: Fail fail if the library is
configured to not use futexes.
Clang and EDG say the class member access expressions __urng.min() and
__urng.max() are not constant expressions, because the object expression
__urng is not usable in a constant expresion. Use a qualified-id to call
those static member functions instead.
Co-authored-by: Stephan Bergmann <sbergman@redhat.com>
libstdc++-v3/ChangeLog:
* include/bits/uniform_int_dist.h (uniform_int_distribution::_S_nd):
Use qualified-id to refer to static member functions.
This separates the definition of std::__call_proxy into two funcions,
one for TLS and one for non-TLS, to make them easier to read. It also
replaces the __get_once_functor_lock_ptr() internal helper with a new
set_lock_ptr(unique_lock<mutex>*) function so that __once_proxy doesn't
need to call it twice.
libstdc++-v3/ChangeLog:
* src/c++11/mutex.cc [_GLIBCXX_HAVE_TLS] (__once_proxy): Define
separately for TLS targets.
[!_GLIBCXX_HAVE_TLS] (__get_once_functor_lock_ptr): Replace with ...
(set_lock_ptr): ... this. Set new value and return previous
value.
[!_GLIBCXX_HAVE_TLS] (__set_once_functor_lock_ptr): Adjust to
use set_lock_ptr.
[!_GLIBCXX_HAVE_TLS] (__once_proxy): Likewise.
The current implementation of std::call_once uses pthread_once, which
only meets the C++ requirements when compiled with support for
exceptions. For most glibc targets and all non-glibc targets,
pthread_once does not work correctly if the init_routine exits via an
exception. The pthread_once_t object is left in the "active" state, and
any later attempts to run another init_routine will block forever.
This change makes std::call_once work correctly for Linux targets, by
replacing the use of pthread_once with a futex, based on the code from
__cxa_guard_acquire. For both glibc and musl, the Linux implementation
of pthread_once is already based on futexes, and pthread_once_t is just
a typedef for int, so this change does not alter the layout of
std::once_flag. By choosing the values for the int appropriately, the
new code is even ABI compatible. Code that calls the old implementation
of std::call_once will use pthread_once to manipulate the int, while new
code will use the new std::once_flag members to manipulate it, but they
should interoperate correctly. In both cases, the int is initially zero,
has the lowest bit set when there is an active execution, and equals 2
after a successful returning execution. The difference with the new code
is that exceptional exceptions are correctly detected and the int is
reset to zero.
The __cxa_guard_acquire code (and musl's pthread_once) use an additional
state to say there are other threads waiting. This allows the futex wake
syscall to be skipped if there is no contention. Glibc doesn't use a
waiter bit, so we have to unconditionally issue the wake in order to be
compatible with code calling the old std::call_once that uses Glibc's
pthread_once. If we know that we're using musl (and musl's pthread_once
doesn't change) it would be possible to set a waiting state and check
for it in std::once_flag::_M_finish(bool), but this patch doesn't do
that.
This doesn't fix the bug for non-linux targets. A similar approach could
be used for targets where we know the definition of pthread_once_t is a
mutex and an integer. We could make once_flag._M_activate() use
pthread_mutex_lock on the mutex member within the pthread_once_t, and
then only set the integer if the execution finishes, and then unlock the
mutex. That would require careful study of each target's pthread_once
implementation and that work is left for a later date.
This also fixes PR 55394 because pthread_once is no longer needed, and
PR 84323 because the fast path is now just an atomic load.
As a consequence of the new implementation that doesn't use
pthread_once, we can also make std::call_once work for targets with no
gthreads support. The code for the single-threaded implementation
follows the same methods as on Linux, but with no need for atomics or
futexes.
libstdc++-v3/ChangeLog:
PR libstdc++/55394
PR libstdc++/66146
PR libstdc++/84323
* config/abi/pre/gnu.ver (GLIBCXX_3.4.29): Add new symbols.
* include/std/mutex [!_GLIBCXX_HAS_GTHREADS] (once_flag): Define
even when gthreads is not supported.
(once_flag::_M_once) [_GLIBCXX_HAVE_LINUX_FUTEX]: Change type
from __gthread_once_t to int.
(once_flag::_M_passive(), once_flag::_M_activate())
(once_flag::_M_finish(bool), once_flag::_Active_execution):
Define new members for futex and non-threaded implementation.
[_GLIBCXX_HAS_GTHREADS] (once_flag::_Prepare_execution): New
RAII helper type.
(call_once): Use new members of once_flag.
* src/c++11/mutex.cc (std::once_flag::_M_activate): Define.
(std::once_flag::_M_finish): Define.
* testsuite/30_threads/call_once/39909.cc: Do not require
gthreads.
* testsuite/30_threads/call_once/49668.cc: Likewise.
* testsuite/30_threads/call_once/60497.cc: Likewise.
* testsuite/30_threads/call_once/call_once1.cc: Likewise.
* testsuite/30_threads/call_once/dr2442.cc: Likewise.
* testsuite/30_threads/call_once/once_flag.cc: Add test for
constexpr constructor.
* testsuite/30_threads/call_once/66146.cc: New test.
* testsuite/30_threads/call_once/constexpr.cc: Removed.
* testsuite/30_threads/once_flag/cons/constexpr.cc: Removed.
For platforms like Mingw and Cygwin, cygwin refuses to generate the
shared library without using -no-undefined.
Attached patch makes sure the right flags are used, since libtool is
already used to link libstdc++.
libstdc++-v3/ChangeLog:
* src/Makefile.am (libstdc___la_LINK): Add lt_host_flags.
* src/Makefile.in: Regenerate.
This meets the requirement that std::is_integral_v<wchar_t> is true,
even when full library support for wchar_t via specializations of
char_traits etc. is not provided. This is done by checking
__WCHAR_TYPE__ to see if the compiler knows about the type, rather than
checking the library's own _GLIBCXX_USE_WCHAR_T autoconf macro.
This assumes that the C++ compiler correctly defines wchar_t as a
distinct type, not a typedef for one of the other integeral types. This
is always true for G++ and should be true for any supported non-GNU
compilers.
Similarly, the std::make_unsigned and std::make_signed traits and the
internal helpers std::__is_integer and std::__is_char are also changed
to depend on the same macro.
libstdc++-v3/ChangeLog:
* include/std/type_traits (is_integral<wchar_t>)
(make_unsigned<wchar_t>, make_signed<wchar_t>): Define based
on #ifdef __WCHAR_TYPE__ instead of _GLIBCXX_USE_WCHAR_T.
* include/bits/cpp_type_traits.h (__is_integer<wchar_t>)
(__is_char<wchar_t>): Likewise.
The transition algorithm for std::shuffle_order_engine uses long double
to ensure that the value (max() - min() + 1) can be accurately
represented, to avoid bias in the shuffling. However, when the base
engine's range is small enough we can avoid slower long double
arithmetic by using double. For example, long double is unnecessary for
any base engine returning 32-bit values.
This makes std::knuth_b::operator() about 15% faster on x86_64, and
probably even more on targets where long double uses soft-float.
libstdc++-v3/ChangeLog:
* include/bits/random.h (independent_bit_engine): Fix typo
in comment.
(shuffle_order_engine): Fix incorrect description in comment.
* include/bits/random.tcc (__representable_as_double
(__p1_representable_as_double): New helper functions.
(shuffle_order_engine::operator()): Use double for calculation
if (max() - min() + 1) is representable as double.
* testsuite/26_numerics/random/pr60037-neg.cc: Adjust dg-error
line number.
My previous commit for this PR changed the types from long double to
double, but didn't change the uses of __builtin_ceill and
__builtin_floorl. It also failed to change the non-inline functions in
src/c++11/hashtable_c++0x.cc. This should fix it properly now.
libstdc++-v3/ChangeLog:
PR libstdc++/96958
* include/bits/hashtable_policy.h (_Prime_rehash_policy)
(_Power2_rehash_policy): Use ceil and floor instead of ceill and
floorl.
* src/c++11/hashtable_c++0x.cc (_Prime_rehash_policy): Likewise.
Use double instead of long double.
This works around a subtle issue where instantiating the begin()/end()
member of some views (as part of return type deduction) inadvertently
requires computing the satisfaction value of range<foo_view>.
This is problematic because the constraint range<foo_view> requires the
begin()/end() member to be callable. But it's not callable until we've
deduced its return type, so evaluation of range<foo_view> yields false
at this point. And if after both members are instantiated (and their
return types deduced) we evaluate range<foo_view> again, this time it
will yield true since the begin()/end() members are now both callable.
This makes the program ill-formed according to [temp.constr.atomic]/3:
If, at different points in the program, the satisfaction result is
different for identical atomic constraints and template arguments, the
program is ill-formed, no diagnostic required.
The views affected by this issue are those whose begin()/end() member
has a placeholder return type and that member initializes an _Iterator
or _Sentinel object from a reference to *this. The second condition is
relevant because it means explicit conversion functions are considered
during overload resolution (as per [over.match.copy], I think), and
therefore it causes g++ to check the constraints of the conversion
function view_interface<foo_view>::operator bool(). And this conversion
function's constraints indirectly require range<foo_view>.
This issue is observable on trunk only with basic_istream_view (as in
the testcase in the PR). But a pending patch that makes g++ memoize
constraint satisfaction values indefinitely (it currently invalidates
the satisfaction cache on various events) causes many existing tests for
the other affected views to fail, because range<foo_view> then remains
false for the whole compilation.
This patch works around this issue by adjusting the constructors of the
_Iterator and _Sentinel types of the affected views to take their
foo_view argument by pointer instead of by reference, so that g++ no
longer considers explicit conversion functions when resolving the
direct-initialization inside these views' begin()/end() members.
libstdc++-v3/ChangeLog:
PR libstdc++/97600
* include/std/ranges (basic_istream_view::begin): Initialize
_Iterator from 'this' instead of '*this'.
(basic_istream_view::_Iterator::_Iterator): Adjust constructor
accordingly.
(filter_view::_Iterator::_Iterator): Take a filter_view*
argument instead of a filter_view& argument.
(filter_view::_Sentinel::_Sentinel): Likewise.
(filter_view::begin): Initialize _Iterator from 'this' instead
of '*this'.
(filter_view::end): Likewise.
(transform_view::_Iterator::_Iterator): Take a _Parent* instead
of a _Parent&.
(filter_view::_Iterator::operator+): Adjust accordingly.
(filter_view::_Iterator::operator-): Likewise.
(filter_view::begin): Initialize _Iterator from 'this' instead
of '*this'.
(filter_view::end): Likewise.
(join_view::_Iterator): Take a _Parent* instead of a _Parent&.
(join_view::_Sentinel): Likewise.
(join_view::begin): Initialize _Iterator from 'this' instead of
'*this'.
(join_view::end): Initialize _Sentinel from 'this' instead of
'*this'.
(split_view::_OuterIter): Take a _Parent& instead of a _Parent*.
(split_view::begin): Initialize _OuterIter from 'this' instead
of '*this'.
(split_view::end): Likewise.
* testsuite/std/ranges/97600.cc: New test.
This makes some range adaptors model the borrowed_range concept if they
are adapting a borrowed range. This hasn't been added to the C++23
working paper yet, but it has been approved by LWG, and the
recommendation is to treat it as a defect report for C++20 as well.
libstdc++-v3/ChangeLog:
* include/std/ranges (enable_borrowed_view<take_view<T>>)
(enable_borrowed_view<drop_view<T>>)
(enable_borrowed_view<drop_while_view<T>>)
(enable_borrowed_view<reverse_view<T>>)
(enable_borrowed_view<common_view<T>>)
(enable_borrowed_view<elements_view<T>>): Add partial
specializations as per P2017R1.
* testsuite/std/ranges/adaptors/conditionally_borrowed.cc:
New test.
These calculations were changed to use long double nearly ten years ago
in order to get more precision than float:
https://gcc.gnu.org/pipermail/libstdc++/2011-September/036420.html
However, double should be sufficient, whlie being potentially faster
than long double, and not requiring soft FP calculations for targets
without native long double support.
libstdc++-v3/ChangeLog:
PR libstdc++/96958
* include/bits/hashtable_policy.h (_Prime_rehash_policy)
(_Power2_rehash_policy): Use double instead of long double.
The class template semiregular-box<T> of [range.semi.wrap] is specified
to value-initialize the underlying object whenever its type is default
initializable. Our primary template for __detail::__box respects this
requirement, but the recently added partial specialization (for types
that are already semiregular) does not.
This patch fixes this issue, and additionally makes the corresponding in
place constructor explicit (as in the primary template).
libstdc++-v3/ChangeLog:
* include/std/ranges (__detail::__box): For the partial
specialization used by types that are already semiregular,
make the default constructor value-initialize the underlying
object instead of default-initializing it. Make its in place
constructor explicit.
* testsuite/std/ranges/adaptors/detail/semiregular_box.cc:
Augment test.
The 20_util/unique_ptr/creation/for_overwrite.cc testcase relies on
operator new, which requires special features on AIX. This patch
disables the testcase.
libstdc++-v3/ChangeLog:
* testsuite/20_util/unique_ptr/creation/for_overwrite.cc: XFAIL on AIX.
This should fix a bootstrap error on Solaris, due to some of the new
symbols matching old patterns as well as new ones.
libstdc++-v3/ChangeLog:
* config/abi/pre/gnu.ver (GLIBCXX_3.4.21): Tighten patterns
for old <sstream> symbols some more.
libstdc++-v3/ChangeLog:
* include/bits/ranges_util.h (subrange::subrange(R&&)): Use
direct-initialization instead of list-initialization, so a
potential narrowing conversion from ranges::size(r) to the
stored size isn't ill-formed.
These are usually suppressed in system headers, but should be fixed
anyway.
libstdc++-v3/ChangeLog:
* include/bits/parse_numbers.h (_Select_int_base): Avoid
narrowing conversion in constant expression.
* include/experimental/buffer (buffer_copy): Avoid narrowing
conversion.
* include/experimental/internet (hash<>::operator()): Do not
use deprecated 'argument_type' member.
* include/std/variant (variant::emplace): Use cast instead
of implicit conversion from size_t to narrower unsigned type.
These tests just return true without checking that the results of the
algorithms. Although it should be safe to assume that the algorithms
behave the same at compile-time as at run-time, we can use these tests
to verify it.
This replaces each 'return true' statement with a condition that depends
on the basic functionality of the algorithm, such as returning an
iterator to the right position.
libstdc++-v3/ChangeLog:
* testsuite/25_algorithms/all_of/constexpr.cc: Check result of
the algorithm.
* testsuite/25_algorithms/any_of/constexpr.cc: Likewise.
* testsuite/25_algorithms/binary_search/constexpr.cc: Likewise.
* testsuite/25_algorithms/copy_backward/constexpr.cc: Likewise.
* testsuite/25_algorithms/count/constexpr.cc: Likewise.
* testsuite/25_algorithms/equal/constexpr.cc: Likewise.
* testsuite/25_algorithms/equal_range/constexpr.cc: Likewise.
* testsuite/25_algorithms/fill/constexpr.cc: Likewise.
* testsuite/25_algorithms/find_end/constexpr.cc: Likewise.
* testsuite/25_algorithms/find_if/constexpr.cc: Likewise.
* testsuite/25_algorithms/is_partitioned/constexpr.cc: Likewise.
* testsuite/25_algorithms/is_permutation/constexpr.cc: Likewise.
* testsuite/25_algorithms/is_sorted_until/constexpr.cc:
Likewise.
* testsuite/25_algorithms/lexicographical_compare/constexpr.cc:
Likewise.
* testsuite/25_algorithms/lower_bound/constexpr.cc: Likewise.
* testsuite/25_algorithms/merge/constexpr.cc: Likewise.
* testsuite/25_algorithms/mismatch/constexpr.cc: Likewise.
* testsuite/25_algorithms/none_of/constexpr.cc: Likewise.
* testsuite/25_algorithms/partition_copy/constexpr.cc: Likewise.
* testsuite/25_algorithms/remove_copy/constexpr.cc: Likewise.
* testsuite/25_algorithms/remove_copy_if/constexpr.cc: Likewise.
* testsuite/25_algorithms/remove_if/constexpr.cc: Likewise.
* testsuite/25_algorithms/replace_if/constexpr.cc: Likewise.
* testsuite/25_algorithms/reverse/constexpr.cc: Likewise.
* testsuite/25_algorithms/reverse_copy/constexpr.cc: Likewise.
* testsuite/25_algorithms/rotate_copy/constexpr.cc: Likewise.
* testsuite/25_algorithms/search/constexpr.cc: Likewise.
* testsuite/25_algorithms/set_difference/constexpr.cc: Likewise.
* testsuite/25_algorithms/set_intersection/constexpr.cc:
Likewise.
* testsuite/25_algorithms/set_symmetric_difference/constexpr.cc:
Likewise.
* testsuite/25_algorithms/set_union/constexpr.cc: Likewise.
* testsuite/25_algorithms/unique_copy/constexpr.cc: Likewise.
* testsuite/25_algorithms/upper_bound/constexpr.cc: Likewise.
This extends the fast path to also work when the URBG's range of
possible values is not the entire range of its result_type. Previously,
the slow path would be used for engines with a uint_fast32_t result type
if that type is actually a typedef for uint64_t rather than uint32_t.
After this change, the generator's result_type is not important, only
the range of possible value that generator can produce. If the
generator's range is exactly UINT64_MAX then the calculation will be
done using 128-bit and 64-bit integers, and if the range is UINT32_MAX
it will be done using 64-bit and 32-bit integers.
In practice, this benefits most of the engines and engine adaptors
defined in [rand.predef] on x86_64-linux and other 64-bit targets. This
is because std::minstd_rand0 and std::mt19937 and others use
uint_fast32_t, which is a typedef for uint64_t.
The code now makes use of the recently-clarified requirement that the
generator's min() and max() functions are usable in constant
expressions (see LWG 2154).
libstdc++-v3/ChangeLog:
* include/bits/uniform_int_dist.h (_Power_of_two): Add
constexpr.
(uniform_int_distribution::_S_nd): Add static_assert to ensure
the wider type is twice as wide as the result type.
(uniform_int_distribution::__generate_impl): Add static_assert
and declare variables as constexpr where appropriate.
(uniform_int_distribution:operator()): Likewise. Only consider
the uniform random bit generator's range of possible results
when deciding whether _S_nd can be used, not the __uctype type.
