This implements the C++23 change "Poison Pills are Too Toxic". This
makes sense to do unconditionally for C++20, as the corner cases that it
fixes are considered to be defects in the C++20 design (e.g. LWG3480 was
needed to fix directory iterators because of these pills being too
toxic).
libstdc++-v3/ChangeLog:
* include/bits/iterator_concepts.h (__imove::iter_move): Define
poison pill as deleted for consistency.
(__access::begin): Replace with a single declaration.
* include/bits/ranges_base.h (__access::end, __access::rbegin)
(__access::rend, __access::size): Likewise.
* include/bits/version.def (ranges): Update value for C++23.
* include/bits/version.h: Regenerate.
* libsupc++/compare (__compare): Add missing poison pill
overloads.
* testsuite/std/ranges/version_c++23.cc: Adjust expected value
of __cpp_lib_ranges.
* testsuite/std/ranges/access/p2602.cc: New test.
This makes the naming of the CPO types and namespaces simpler and more
consistent. With this change the string "cust" won't appear in
diagnostics related to these CPOs, which avoids confusion about what it
means (customization? customer?). Users don't really need to care that
these are called "customization point objects", so don't show them the
string "cust". Names like "__imove::_IterMove" are preferable to names
like "__cust_imove::_IMove" as the former is more obviously related to
the public API "ranges::iter_move".
Instead of a plethora of inline namespaces for all the different CPO
objects, define them all in an inline namespace called _Cpo (which isn't
shown to users anyway, unlike the types of those objects).
libstdc++-v3/ChangeLog:
* include/bits/iterator_concepts.h (ranges::__cust_imove):
Rename to ranges::__imove.
(_IMove): Rename to _IterMove.
(ranges::__cust_iswap): Rename to ranges::__iswap.
(ranges::__cust): Rename to ranges::_Cpo.
(ranges::__cust_access): Rename to ranges::__access.
* include/bits/ranges_base.h (ranges::__cust_access): Rename to
ranges::__access.
(ranges::__cust): Rename to ranges::_Cpo.
* include/std/concepts (ranges::__cust_swap): Rename to
ranges::__swap.
(ranges::__cust): Rename to ranges::_Cpo.
* libsupc++/compare (__cmp_cust): Rename to __compare.
(__cmp_algo): Rename to _Cpo.
This constructor should only ever be used with a literal 0 as the
argument, so we can make it consteval. This has the nice advantage that
it is expanded immediately in the front end, and so GDB will never step
into the __cmp_cat::__unseq::__unseq(__unseq*) constructor that is
uninteresting and probably confusing to users.
libstdc++-v3/ChangeLog:
* libsupc++/compare (__cmp_cat::__unseq): Make ctor consteval.
* testsuite/18_support/comparisons/categories/zero_neg.cc: Prune
excess errors caused by invalid consteval calls.
PR middle-end/109849
* include/bits/c++config (std::__terminate): Mark cold.
* include/bits/functexcept.h: Mark everything as cold.
* libsupc++/exception: Mark terminate and unexpected as cold.
[except.handle]/7 says that when we enter std::terminate due to a throw,
that is considered an active handler. We already implemented that properly
for the case of not finding a handler (__cxa_throw calls __cxa_begin_catch
before std::terminate) and the case of finding a callsite with no landing
pad (the personality function calls __cxa_call_terminate which calls
__cxa_begin_catch), but for the case of a throw in a try/catch in a noexcept
function, we were emitting a cleanup that calls std::terminate directly
without ever calling __cxa_begin_catch to handle the exception.
A straightforward way to fix this seems to be calling __cxa_call_terminate
instead. However, that requires exporting it from libstdc++, which we have
not previously done. Despite the name, it isn't actually part of the ABI
standard. Nor is __cxa_call_unexpected, as far as I can tell, but that one
is also used by clang. For this case they use __clang_call_terminate; it
seems reasonable to me for us to stick with __cxa_call_terminate.
I also change __cxa_call_terminate to take void* for simplicity in the front
end (and consistency with __cxa_call_unexpected) but that isn't necessary if
it's undesirable for some reason.
This patch does not fix the issue that representing the noexcept as a
cleanup is wrong, and confuses the handler search; since it looks like a
cleanup in the EH tables, the unwinder keeps looking until it finds the
catch in main(), which it should never have gotten to. Without the
try/catch in main, the unwinder would reach the end of the stack and say no
handler was found. The noexcept is a handler, and should be treated as one,
as it is when the landing pad is omitted.
The best fix for that issue seems to me to be to represent an
ERT_MUST_NOT_THROW after an ERT_TRY in an action list as though it were an
ERT_ALLOWED_EXCEPTIONS (since indeed it is an exception-specification). The
actual code generation shouldn't need to change (apart from the change made
by this patch), only the action table entry.
PR c++/97720
gcc/cp/ChangeLog:
* cp-tree.h (enum cp_tree_index): Add CPTI_CALL_TERMINATE_FN.
(call_terminate_fn): New macro.
* cp-gimplify.cc (gimplify_must_not_throw_expr): Use it.
* except.cc (init_exception_processing): Set it.
(cp_protect_cleanup_actions): Return it.
gcc/ChangeLog:
* tree-eh.cc (lower_resx): Pass the exception pointer to the
failure_decl.
* except.h: Tweak comment.
libstdc++-v3/ChangeLog:
* libsupc++/eh_call.cc (__cxa_call_terminate): Take void*.
* config/abi/pre/gnu.ver: Add it.
gcc/testsuite/ChangeLog:
* g++.dg/eh/terminate2.C: New test.
In the ABI's two-phase EH model, first we walk the stack looking for a
handler, then we walk the stack running cleanups until we reach that
handler. In the cleanup phase, we shouldn't redundantly check the handlers
along the way, e.g. when walking through g():
void f() { throw 42; }
void g() { try { f(); } catch (void *) { } }
int main() { try { g(); } catch (int) { } }
libstdc++-v3/ChangeLog:
* libsupc++/eh_personality.cc (PERSONALITY_FUNCTION): Don't check
handlers in the cleanup phase.
libstdc++-v3/ChangeLog:
* doc/xml/manual/extensions.xml: Fix example to declare and
qualify std::free, and use NULL instead of 0.
* doc/html/manual/ext_demangling.html: Regenerate.
* libsupc++/cxxabi.h: Adjust doxygen comments.
The non-reserved names 'val' and 'dest' were being used in our headers
but haven't been added to the 17_intro/names.cc test. That's because
they are used by <asm-generic/posix_types.h> and <netinet/tcp.h>
respecitvely on glibc-based systems.
libstdc++-v3/ChangeLog:
* include/bits/fs_ops.h (create_directory): Use reserved name
for parameter.
* include/bits/ranges_algo.h (__contains_subrange_fn):
Likewise.
* include/bits/regex_automaton.h (_State_base::_M_print):
Likewise.
* include/bits/regex_automaton.tcc(_State_base::_M_print):
Likewise.
* include/bits/regex_scanner.tcc(_Scanner::_M_print): Likewise.
* include/experimental/bits/fs_ops.h (create_directory):
Likewise.
* include/std/mutex (timed_mutex::_M_clocklock): Likewise.
(recursive_timed_mutex:_M_clocklock): Likewise.
* include/std/tuple (basic_common_reference): Likewise.
* libsupc++/cxxabi_init_exception.h
(__cxa_init_primary_exception): Likewise.
* testsuite/17_intro/names.cc: Add checks.
For H8/300 size_t is 32 bits wide, but (unsigned char)buf[2] << 16
promotes to int which is only 16 bits wide. The shift is then undefined.
This fixes it by converting to size_t before shifting.
libstdc++-v3/ChangeLog:
PR libstdc++/107885
* libsupc++/hash_bytes.cc (_Hash_bytes): Convert to size_t
instead of implicit integer promotion to 16 bits.
Fix some problems noticed with -Wsystem-headers.
libstdc++-v3/ChangeLog:
* include/bits/stl_tempbuf.h (_Temporary_buffer): Disable
warnings about get_temporary_buffer being deprecated.
* include/ext/functional (mem_fun1, mem_fun1_ref): Disable
warnings about mem_fun1_t, const_mem_fun1_t, mem_fun1_ref_t and
const_mem_fun1_ref_t being deprecated.
* include/std/array (__array_traits<T, 0>): Remove artificial
attributes which give warnings about being ignored.
* include/std/spanstream (basic_spanbuf::setbuf): Add assertion
and adjust to avoid narrowing warning.
* libsupc++/exception_ptr.h [!__cpp_rtti && !__cpp_exceptions]
(make_exception_ptr): Add missing inline specifier.
__pbase_type_info::__do_catch(), used to catch pointer type exceptions,
did not check if the type info object to compare against is a pointer
type info object before doing a static down-cast to a pointer type info
object. If RTTI is disabled, this leads to the following situation:
Since a pointer type info object has additional fields, they would
end up being undefined if the actual type info object was not a pointer
type info object.
A simple check has been added before the down-cast happens.
Note that a consequence of this check is that exceptions of type
pointer-to-member cannot be caught anymore.
In case RTTI is enabled, this does not seem to be a problem because
RTTI-based checks would run before and prevent running into the bad
down-cast. Hence, the fix is disabled if RTTI is enabled and exceptions
of type pointer-to-member can still be caught.
libstdc++-v3/ChangeLog:
PR libstdc++/105387
* libsupc++/pbase_type_info.cc (__do_catch) [!__cpp_rtti]: Add
check that the thrown type is actually a pointer.
* testsuite/18_support/105387.cc: New test.
* testsuite/18_support/105387_memptr.cc: New test.
Signed-off-by: Jakob Hasse <jakob.hasse@espressif.com>
Since this is a trivial type, we probably don't need to do anything to
ensure it's still accessible after other static dtors.
libstdc++-v3/ChangeLog:
PR libstdc++/107500
* libsupc++/eh_globals.cc (eh_globals): Remove immortalizing
wrapper.
(__cxxabiv1::__cxa_get_globals_fast): Adjust.
(__cxxabiv1::__cxa_get_globals): Adjust.
As in r12-6867-ge20486d508afdf we need to define _GNU_SOURCE explicitly
for Cygwin, because configure finds it in libc but it isn't declared
unless we request it.
libstdc++-v3/ChangeLog:
PR libstdc++/107511
* libsupc++/eh_alloc.cc (_GNU_SOURCE): Define.
We don't need these 'unused' members because they're never used, and a
union with a single variant member is fine.
libstdc++-v3/ChangeLog:
* libsupc++/eh_globals.cc (constant_init::unused): Remove.
* src/c++11/system_error.cc (constant_init::unused): Remove.
* src/c++17/memory_resource.cc (constant_init::unused): Remove.
Jon pointed out that we have TODO: _Bfloat16 in <compare>.
Right now _S_fp_fmt() returns _Binary16 for _Float16, __fp16 as well
as __bf16 and it actually works because we don't have a special handling
of _Binary16. So, either we could just document that, but I'm a little bit
afraid if HPPA or MIPS don't start supporting _Float16 and/or __bf16.
If they do, we have the
#if defined __hppa__ || (defined __mips__ && !defined __mips_nan2008)
// IEEE 754-1985 allowed the meaning of the quiet/signaling
// bit to be reversed. Flip that to give desired ordering.
if (__builtin_isnan(__x) && __builtin_isnan(__y))
{
using _Int = decltype(__ix);
constexpr int __nantype = __fmt == _Binary32 ? 22
: __fmt == _Binary64 ? 51
: __fmt == _Binary128 ? 111
: -1;
constexpr _Int __bit = _Int(1) << __nantype;
__ix ^= __bit;
__iy ^= __bit;
}
#endif
code, the only one where we actually care whether something is
_Binary{32,64,128} (elsewhere we just care about the x86 and m68k 80bits
or double double or just floating point type's sizeof) and we'd need
to handle there _Binary16 and/or _Bfloat16.
So this patch uses different enum for it even when it isn't needed right
now, after all _Binary16 isn't needed either and we could just use
_Binary32...
2022-11-02 Jakub Jelinek <jakub@redhat.com>
* libsupc++/compare (_Strong_order::_Fp_fmt): Add _Bfloat16.
(_Strong_order::_Bfloat16): New static data member.
(_Strong_order::_S_fp_fmt): Return _Bfloat16 for std::bfloat16_t.
This patch adds the new thread model `mcf`, which implements mutexes
and condition variables with the mcfgthread library.
Source code for mcfgthread is available at <https://github.com/lhmouse/mcfgthread>.
config/ChangeLog:
* gthr.m4 (GCC_AC_THREAD_HEADER): Add new case for `mcf` thread
model
gcc/ChangeLog:
* config/i386/mingw-mcfgthread.h: New file
* config/i386/mingw32.h: Add builtin macro and default libraries
for mcfgthread when thread model is `mcf`
* config.gcc: Include 'i386/mingw-mcfgthread.h' when thread model
is `mcf`
* configure.ac: Recognize `mcf` as a valid thread model
* config.in: Regenerate
* configure: Regenerate
libatomic/ChangeLog:
* configure.tgt: Add new case for `mcf` thread model
libgcc/ChangeLog:
* config.host: Add new cases for `mcf` thread model
* config/i386/gthr-mcf.h: New file
* config/i386/t-mingw-mcfgthread: New file
* config/i386/t-slibgcc-cygming: Add mcfgthread for libgcc DLL
* configure: Regenerate
libstdc++-v3/ChangeLog:
* libsupc++/atexit_thread.cc (__cxa_thread_atexit): Use
implementation from mcfgthread if available
* libsupc++/guard.cc (__cxa_guard_acquire, __cxa_guard_release,
__cxa_guard_abort): Use implementations from mcfgthread if
available
* configure: Regenerate
For a zero-sized static pool we can completely elide all code for the EH
pool.
We no longer need to adjust the static buffer size to ensure at least
one free_entry can be created in it, because we no longer use a static
buffer at all if obj_count == 0. If the buffer exists, obj_count >= 1
and the buffer will be much larger than sizeof(free_entry).
libstdc++-v3/ChangeLog:
* libsupc++/eh_alloc.cc [USE_POOL]: New macro.
[!USE_POOL] (__gnu_cxx::__freeres, pool): Do not define.
[_GLIBCXX_EH_POOL_STATIC] (pool::arena): Do not use std::max.
(__cxxabiv1::__cxa_allocate_exception) [!USE_POOL]: Do not use
pool.
(__cxxabiv1::__cxa_free_exception) [!USE_POOL]: Likewise.
(__cxxabiv1::__cxa_allocate_dependent_exception) [!USE_POOL]:
Likewise.
(__cxxabiv1::__cxa_free_dependent_exception) [!USE_POOL]:
Likewise.
The __scoped_lock type should be used unqualified so that we always
refer to pool::__scoped_lock, which might be the dummy fallback
implementation.
The __mutex and __scoped_lock types in <ext/concurrence.h> already work
fine without __GTHREADS being defined, but that header isn't included at
all unless _GLIBCXX_HOSTED != 0. The fallback implementation should be
used for ! _GLIBCXX_HOSTED instead of for !defined __GTHREADS.
libstdc++-v3/ChangeLog:
PR bootstrap/107221
* libsupc++/eh_alloc.cc (pool): Change preprocessor condition
for using __mutex from __GTHREADS to _GLIBCXX_HOSTED.
(pool::allocate): Remove namespace qualification to use
pool::__scoped_lock instead of __gnu_cxx::__scoped_lock.
Implement a long-standing request to support tuning the size of the
emergency buffer for allocating exceptions after malloc fails, or to
disable that buffer entirely.
It's now possible to disable the dynamic allocation of the buffer and
use a fixed-size static buffer, via --enable-libstdcxx-static-eh-pool.
This is a built-time choice that is baked into libstdc++ and so affects
all code linked against that build of libstdc++.
The size of the pool can be set by --with-libstdcxx-eh-pool-obj-count=N
which is measured in units of sizeof(void*) not bytes. A given exception
type such as std::system_error depends on the target, so giving a size
in bytes wouldn't be portable across 16/32/64-bit targets.
When libstdc++ is configured to use a dynamic buffer, the size of that
buffer can now be tuned at runtime by setting the GLIBCXX_TUNABLES
environment variable (c.f. PR libstdc++/88264). The number of exceptions
to reserve space for is controlled by the "glibcxx.eh_pool.obj_count"
and "glibcxx.eh_pool.obj_size" tunables. The pool will be sized to be
able to allocate obj_count exceptions of size obj_size*sizeof(void*) and
obj_count "dependent" exceptions rethrown by std::rethrow_exception.
With the ability to tune the buffer size, we can reduce the default pool
size on 32-bit and 16-bit targets. Most users never need to throw 1kB
exceptions in parallel from hundreds of threads after malloc is OOM. The
users who do need that can use the tunables to select larger sizes.
The old defaults can be chosen at runtime by setting GLIBCXX_TUNABLES
to:
64-bit: glibcxx.eh_pool.obj_count=64:glibcxx.eh_pool.obj_size=112
32-bit: glibcxx.eh_pool.obj_count=32:glibcxx.eh_pool.obj_size=104
Or approximated by configuring with:
64-bit: --with-libstdcxx-eh-pool-obj-count=252
32-bit: --with-libstdcxx-eh-pool-obj-count=94
libstdc++-v3/ChangeLog:
PR libstdc++/68606
* Makefile.in: Regenerate.
* acinclude.m4 (GLIBCXX_EMERGENCY_EH_ALLOC): New macro.
* configure: Regenerate.
* configure.ac: Use GLIBCXX_EMERGENCY_EH_ALLOC.
* crossconfig.m4: Check for secure_getenv.
* doc/Makefile.in: Regenerate.
* doc/xml/manual/configure.xml: Document new configure options.
* doc/xml/manual/evolution.xml: Document addition of tunables.
* doc/xml/manual/using_exceptions.xml: Document emergency
buffer and tunables.
* doc/html/*: Regenerate.
* include/Makefile.in: Regenerate.
* libsupc++/Makefile.am: Use EH_POOL_FLAGS.
* libsupc++/Makefile.in: Regenerate.
* libsupc++/eh_alloc.cc (EMERGENCY_OBJ_SIZE): Define in units
of sizeof(void*) not including the ABI's exception header.
(EMERGENCY_OBJ_COUNT): Define as target-independent calculation
based on word size.
(MAX_OBJ_COUNT): Define macro for upper limit on pool size.
(pool) [_GLIBCXX_EH_POOL_STATIC]: Use fixed-size buffer.
(pool::buffer_size_in_bytes): New static member function.
(pool::pool): Parse GLIBCXX_TUNABLES environment variable to set
pool size at runtime.
(pool::in_pool): Use std::less<void*> for total order.
(__freeres) [_GLIBCXX_EH_POOL_STATIC]: Do nothing.
(__cxa_free_exception, __cxa_free_dependent_exception): Add
[[unlikely]] attributes.
* po/Makefile.in: Regenerate.
* python/Makefile.in: Regenerate.
* src/Makefile.in: Regenerate.
* src/c++11/Makefile.in: Regenerate.
* src/c++17/Makefile.in: Regenerate.
* src/c++20/Makefile.in: Regenerate.
* src/c++98/Makefile.in: Regenerate.
* src/filesystem/Makefile.in: Regenerate.
* src/libbacktrace/Makefile.in: Regenerate.
* testsuite/Makefile.in: Regenerate.
This change speeds up the simple benchmark below by about 40%.
struct A { virtual ~A() {} };
struct B: A { } b;
A* ap = &b;
void *sink;
int main()
{
for (long i = 0; i < 4000000000L; ++i)
sink = dynamic_cast<B*>(ap);
}
libstdc++-v3/ChangeLog:
* libsupc++/dyncast.cc (__dynamic_cast): Avoid virtual function
call in simple success case.
This probably has never actually affected anyone in practice. The normal
ABI implementation just uses malloc and only falls back to the pool on
malloc failure. But if that happens a bunch of times the freelist gets out
of order which violates some of the invariants of the freelist (as well as
the comments that follow the bug). The bug is just a comparison reversal
when traversing the freelist in the case where the pointer being returned
to the pool is after the existing freelist.
libstdc++-v3/
* libsupc++/eh_alloc.cc (pool::free): Inverse comparison.
Clear __eh_globals_init's _S_init in the dtor before deleting the
gthread key.
This ensures that, in case any code involved in deleting the key
interacts with eh_globals, the key that is being deleted won't be
used, and the non-thread-specific eh_globals fallback will.
for libstdc++-v3/ChangeLog
* libsupc++/eh_globals.cc [!_GLIBCXX_HAVE_TLS]
(__eh_globals_init::~__eh_globals_init): Clear _S_init first.
This ensures that the single-threaded fallback buffer eh_globals is not
destroyed during program termination, using the same immortalization
technique used for error category objects.
Also ensure that init._M_init can still be read after init has been
destroyed, by making it a static data member.
libstdc++-v3/ChangeLog:
PR libstdc++/105880
* libsupc++/eh_globals.cc (eh_globals): Ensure constant init and
prevent destruction during termination.
(__eh_globals_init::_M_init): Replace with static member _S_init.
(__cxxabiv1::__cxa_get_globals_fast): Update.
(__cxxabiv1::__cxa_get_globals): Likewise.
The non-member swap for std::exception_ptr is in a nested namespace and
so can only be found by ADL currently. Add a using-declaration so that
qualified std::swap calls will use the std::exception_ptr::swap member,
instead of the generic std::swap.
There's no new test for this, because the generic std::swap works, it
just does more work than is necessary.
Also tell Doxygen to replace the __exception_ptr namespace with
"__unspecified__" in the generate docs, so the real name is not
documented.
libstdc++-v3/ChangeLog:
* doc/doxygen/user.cfg.in (PREDEFINED): Replace __exception_ptr
with "__unspecified__".
* libsupc++/exception_ptr.h: Improve doxygen docs.
(__exception_ptr::swap): Also declare in namespace std.
This allows std::rethrow_if_nested to work with -fno-rtti by not
attempting the dynamic_cast if it requires RTTI, since that's ill-formed
with -fno-rtti. The cast will still work if a static upcast to
std::nested_exception is allowed.
Also use if-constexpr to avoid the compile-time overload resolution (and
SFINAE) and run-time dispatching for std::rethrow_if_nested and
std::throw_with_nested.
Also add better doxygen comments throughout the file.
libstdc++-v3/ChangeLog:
* libsupc++/nested_exception.h (throw_with_nested) [C++17]: Use
if-constexpr instead of tag dispatching.
(rethrow_if_nested) [C++17]: Likewise.
(rethrow_if_nested) [!__cpp_rtti]: Do not use dynamic_cast if it
would require RTTI.
* testsuite/18_support/nested_exception/rethrow_if_nested-term.cc:
New test.
These are harmless, but also unnecessary and inconsistent (and their
removal was requested by PR libstdc++/17632).
libstdc++-v3/ChangeLog:
* config/locale/dragonfly/numeric_members.cc: Remove whitespace.
* config/locale/gnu/numeric_members.cc: Likewise.
* include/bits/locale_facets_nonio.h: Likewise.
* libsupc++/typeinfo: Likewise.
The memalign man page on Solaris and QNX lists an additional requirement
for the alignment value that is not present in all implementation of
that non-standard function. For both those targets we should actually be
using posix_memalign anyway, so it doesn't matter. This just adds a
comment making note of that fact.
libstdc++-v3/ChangeLog:
* libsupc++/new_opa.cc (aligned_alloc): Add comment.
Once we no longer care about older compilers without this feature, we
can drop these static data members, so the names don't have to be
visible at class scope.
libstdc++-v3/ChangeLog:
* libsupc++/compare (_Strong_order) [!__cpp_using_enum]: Add
static data members for _Fp_fmt enumerators.
Because this adds a new class template called std::unexpected, we have
to stop declaring the std::unexpected() function (which was deprecated
in C++11 and removed in C++17).
libstdc++-v3/ChangeLog:
* doc/doxygen/user.cfg.in: Add new header.
* include/Makefile.am: Likewise.
* include/Makefile.in: Regenerate.
* include/precompiled/stdc++.h: Add new header.
* include/std/version (__cpp_lib_expected): Define.
* libsupc++/exception [__cplusplus > 202002] (unexpected)
(unexpected_handler, set_unexpected): Do not declare for C++23.
* include/std/expected: New file.
* testsuite/20_util/expected/assign.cc: New test.
* testsuite/20_util/expected/cons.cc: New test.
* testsuite/20_util/expected/illformed_neg.cc: New test.
* testsuite/20_util/expected/observers.cc: New test.
* testsuite/20_util/expected/requirements.cc: New test.
* testsuite/20_util/expected/swap.cc: New test.
* testsuite/20_util/expected/synopsis.cc: New test.
* testsuite/20_util/expected/unexpected.cc: New test.
* testsuite/20_util/expected/version.cc: New test.
I mistakenly believed that VAX floats do not support NaN, but with GCC
__builtin_isnan(__builtin_nan("")) is true. That means my previous
change to <compare> is wrong, because it fails to handle NaN.
When std::numeric_limits<floating-point-type>::is_iec559 is false, as on
VAX, the standard only requires an ordering that is consistent with the
ordering observed by comparison operators. With this change the ordering
is -NaN < numbers < +NaN, and there is no support for different NaN bit
patterns (as I'm not even sure if GCC supports any for VAX).
libstdc++-v3/ChangeLog:
* libsupc++/compare (_Strong_order::_S_fp_cmp) [__vax__]:
Handle NaN.
The VAX float and double format does not support NaN, so the
std::partial_ordering returned by <=> will never be 'unordered'. We can
just use the partial_ordering value as the strong_ordering.
libstdc++-v3/ChangeLog:
* libsupc++/compare (_Strong_ordering::_S_fp_cmp) [__vax__]: Use
<=> comparison.
This removes a FIXME in <compare>, defining the total order for
floating-point types. I originally opened PR96526 to request a new
compiler built-in to implement this, but now that we have std::bit_cast
it can be done entirely in the library.
The implementation is based on the glibc definitions of totalorder,
totalorderf, totalorderl etc.
I think this works for all the types that satisfy std::floating_point
today, and should also work for the types expected to be added by P1467
except for std::bfloat16_t. It also supports some additional types that
don't currently satisfy std::floating_point, such as __float80, but we
probably do want that to satisfy the concept for non-strict modes.
libstdc++-v3/ChangeLog:
PR libstdc++/96526
* libsupc++/compare (strong_order): Add missing support for
floating-point types.
* testsuite/18_support/comparisons/algorithms/strong_order_floats.cc:
New test.
We should use the SUGGEST macro for std::uncaught_exception()
deprecation warnings.
libstdc++-v3/ChangeLog:
* include/bits/allocator.h: Qualify std::allocator_traits in
deprecated warnings.
* libsupc++/exception (uncaught_exception): Add suggestion to
deprecated warning.
Add the <stacktrace> header and a new libstdc++_libbacktrace.a library
that provides the implementation. For now, the new library is only built
if --enable-libstdcxx-backtrace=yes is used. As with the Filesystem TS,
the new library is only provided as a static archive.
libstdc++-v3/ChangeLog:
* acinclude.m4 (GLIBCXX_ENABLE_BACKTRACE): New macro.
* configure.ac: Use GLIBCXX_ENABLE_BACKTRACE.
* include/Makefile.am: Add new header.
* include/Makefile.in: Regenerate.
* include/std/stacktrace: New header.
* include/std/version (__cpp_lib_stacktrace): Define.
* Makefile.in: Regenerate.
* config.h.in: Regenerate.
* configure: Regenerate.
* doc/Makefile.in: Regenerate.
* libsupc++/Makefile.in: Regenerate.
* po/Makefile.in: Regenerate.
* python/Makefile.in: Regenerate.
* src/Makefile.am: Regenerate.
* src/Makefile.in: Regenerate.
* src/c++11/Makefile.in: Regenerate.
* src/c++17/Makefile.in: Regenerate.
* src/c++20/Makefile.in: Regenerate.
* src/c++98/Makefile.in: Regenerate.
* src/filesystem/Makefile.in: Regenerate.
* testsuite/Makefile.in: Regenerate.
* src/libbacktrace/Makefile.am: New file.
* src/libbacktrace/Makefile.in: New file.
* src/libbacktrace/backtrace-rename.h: New file.
* src/libbacktrace/backtrace-supported.h.in: New file.
* src/libbacktrace/config.h.in: New file.
* testsuite/lib/libstdc++.exp (check_effective_target_stacktrace):
New proc.
* testsuite/20_util/stacktrace/entry.cc: New test.
* testsuite/20_util/stacktrace/synopsis.cc: New test.
* testsuite/20_util/stacktrace/version.cc: New test.
This fixes the --disable-hosted-libstdcxx build so that it works with
--without-headers. Currently you need to also use --with-newlib, which
is confusing for users who aren't actually using newlib.
The AM_PROG_LIBTOOL checks are currently skipped for --with-newlib and
--with-avrlibc builds, with this change they are also skipped when using
--without-headers. It would be nice if using --disable-hosted-libstdcxx
automatically skipped those checks, but GLIBCXX_ENABLE_HOSTED comes too
late to make the AM_PROG_LIBTOOL checks depend on $is_hosted.
The checks for EOF, SEEK_CUR etc. cause the build to fail if there is no
<stdio.h> available. Unlike most headers, which get a HAVE_FOO_H macro,
<stdio.h> is in autoconf's default includes, so every check tries to
include it unconditionally. This change skips those checks for
freestanding builds.
Similarly, the checks for <stdint.h> types done by GCC_HEADER_STDINT try
to include <stdio.h> and fail for --without-headers builds. This change
skips the use of GCC_HEADER_STDINT for freestanding. We can probably
stop using GCC_HEADER_STDINT entirely, since only one file uses the
gstdint.h header that is generated, and that could easily be changed to
use <stdint.h> instead. That can wait for stage 1.
We also need to skip the GLIBCXX_CROSSCONFIG stage if --without-headers
was used, since we don't have any of the functions it deals with.
The end result of the changes above is that it should not be necessary
for a --disable-hosted-libstdcxx --without-headers build to also use
--with-newlib.
Finally, compile libsupc++ with -ffreestanding when --without-headers is
used, so that <stdint.h> will use <gcc-stdint.h> instead of expecting it
to come from libc.
libstdc++-v3/ChangeLog:
PR libstdc++/103866
* acinclude.m4 (GLIBCXX_COMPUTE_STDIO_INTEGER_CONSTANTS): Do
nothing for freestanding builds.
(GLIBCXX_ENABLE_HOSTED): Define FREESTANDING_FLAGS.
* configure.ac: Do not use AC_LIBTOOL_DLOPEN when configured
with --without-headers. Do not use GCC_HEADER_STDINT for
freestanding builds.
* libsupc++/Makefile.am (HOSTED_CXXFLAGS): Use -ffreestanding
for freestanding builds.
* configure: Regenerate.
* Makefile.in: Regenerate.
* doc/Makefile.in: Regenerate.
* include/Makefile.in: Regenerate.
* libsupc++/Makefile.in: Regenerate.
* po/Makefile.in: Regenerate.
* python/Makefile.in: Regenerate.
* src/Makefile.in: Regenerate.
* src/c++11/Makefile.in: Regenerate.
* src/c++17/Makefile.in: Regenerate.
* src/c++20/Makefile.in: Regenerate.
* src/c++98/Makefile.in: Regenerate.
* src/filesystem/Makefile.in: Regenerate.
* testsuite/Makefile.in: Regenerate.
This feature is present in the C++23 draft.
With Jakub's recent front-end changes we can implement constexpr
equality by comparing the addresses of std::type_info objects. We do not
need string comparisons, because for constant evaluation cases we know
we aren't dealing with std::type_info objects defined in other
translation units.
The ARM EABI requires that the type_info::operator== function can be
defined out-of-line (and suggests that should be the default), but to be
a constexpr function it must be defined inline (at least for C++23
mode). To meet these conflicting requirements we make the inline version
of operator== call a new __equal function when called at runtime. That
is an alias for the non-inline definition of operator== defined in
libsupc++.
libstdc++-v3/ChangeLog:
* config/abi/pre/gnu.ver (GLIBCXX_3.4.30): Export new symbol for
ARM EABI.
* include/bits/c++config (_GLIBCXX23_CONSTEXPR): Define.
* include/std/version (__cpp_lib_constexpr_typeinfo): Define.
* libsupc++/tinfo.cc: Add #error to ensure non-inline definition
is emitted.
(type_info::__equal): Define alias symbol.
* libsupc++/typeinfo (type_info::before): Combine different
implementations into one.
(type_info::operator==): Likewise. Use address equality for
constant evaluation. Call __equal for targets that require the
definition to be non-inline.
* testsuite/18_support/type_info/constexpr.cc: New test.
This allows std::make_exception_ptr to be used in a translation unit
compiled with -fno-exceptions. This works because the new implementation
added for PR 68297 doesn't need to throw or catch anything. The catch is
there to handle exceptions from the constructor of the exception object,
which we can assume won't happen in a -fno-exceptions TU and so use the
__catch macro instead. If the constructor does throw (because it's
defined in a different TU which was compiled with exceptions enabled)
then that exception will propagate to the make_exception_ptr caller.
That seems acceptable for a program that is trying to mix & match TUs
compiled with and without exceptions, and using types that throw when
constructed. That should be rare, and can't reasonably be expected to
have sensible behaviour.
This also enables the new implementation for targets that use a
non-standard calling convention for the exceptionDestructor callback
(specifically, mingw, which uses __thiscall). All we need to do is mark
the __dest_thunk function template with the right calling convention.
Finally, the useless no-op definition of make_exception_ptr (which is
only used if both RTTI and exceptions are disabled) is marked
always_inline, to ensure that the linker won't keep that definition and
discard the functional ones when both definitions of the function are
present in the link. An alternative would be to add the abi_tag
attribute to the useless definition, but making it always_inline should
work, and it's small enough to always be inlined reliably.
libstdc++-v3/ChangeLog:
PR libstdc++/85813
* libsupc++/exception_ptr.h (__dest_thunk): Add macro for
destructor calling convention.
(make_exception_ptr): Enable non-throwing implementation for
-fno-exceptions and for non-standard calling conventions. Use
always_inline attribute on the useless no-rtti no-exceptions
definition.
* testsuite/18_support/exception_ptr/64241.cc: Add -fno-rtti so
the no-op implementation is still used.
This restores support for std::make_exception_ptr<E&> and for using
std::exception_ptr in C++98.
Because the new non-throwing implementation needs to use std::decay to
handle references the original throwing implementation is used for
C++98.
We also need to change the typeid expression so it doesn't yield the
dynamic type when the function parameter is a reference to a polymorphic
type. Otherwise the new exception object could be caught by any handler
matching the dynamic type, even though the actual exception object is
only a copy of the base class, sliced to the static type.
libstdc++-v3/ChangeLog:
PR libstdc++/103630
* libsupc++/exception_ptr.h (exception_ptr): Fix exception
specifications on inline definitions.
(make_exception_ptr): Decay the template parameter. Use typeid
of the static type.
* testsuite/18_support/exception_ptr/103630.cc: New test.
This adds std::__is_constant_evaluated() as a C++11 wrapper for
__builtin_is_constant_evaluated, but just returning false if the
built-in isn't supported by the compiler. This allows us to use it
throughout the library without checking __has_builtin every time.
Some uses in std::vector and std::string can only be constexpr when the
std::is_constant_evaluated() function actually works, so we might as
well guard them with a relevant macro and call that function directly,
rather than the built-in or std::__is_constant_evaluated().
The remaining checks of the __cpp_lib_is_constant_evaluated macro could
now be replaced by checking __cplusplus >= 202002 instead, but there's
no practical difference. We still need some kind of preprocessor check
there anyway.
libstdc++-v3/ChangeLog:
* doc/doxygen/user.cfg.in (PREDEFINED): Change macro name.
* include/bits/allocator.h (allocate, deallocate): Use
std::__is_constant_evaluated() unconditionally, instead of
checking whether std::is_constant_evaluated() (or the built-in)
can be used.
* include/bits/basic_string.h: Check new macro. call
std::is_constant_evaluated() directly in C++20-only code that is
guarded by a suitable macro.
* include/bits/basic_string.tcc: Likewise.
* include/bits/c++config (__is_constant_evaluated): Define.
(_GLIBCXX_HAVE_BUILTIN_IS_CONSTANT_EVALUATED): Replace with ...
(_GLIBCXX_HAVE_IS_CONSTANT_EVALUATED): New macro.
* include/bits/char_traits.h (char_traits): Replace conditional
calls to std::is_constant_evaluated with unconditional calls to
std::__is_constant_evaluated.
* include/bits/cow_string.h: Use new macro.
* include/bits/ranges_algobase.h (__copy_or_move): Replace
conditional calls to std::is_constant_evaluated with unconditional
calls to std::__is_constant_evaluated.
(__copy_or_move_backward, __fill_n_fn): Likewise.
* include/bits/ranges_cmp.h (ranges::less): Likewise.
* include/bits/stl_algobase.h (lexicographical_compare_three_way):
Likewise.
* include/bits/stl_bvector.h: Call std::is_constant_evaluated
directly in C++20-only code that is guarded by a suitable macro.
* include/bits/stl_construct.h (_Construct, _Destroy, _Destroy_n):
Replace is_constant_evaluated with __is_constant_evaluated.
* include/bits/stl_function.h (greater, less, greater_equal)
(less_equal): Replace __builtin_is_constant_evaluated and
__builtin_constant_p with __is_constant_evaluated.
* include/bits/stl_vector.h: Call std::is_constant_evaluated()
in C++20-only code.
* include/debug/helper_functions.h (__check_singular): Use
__is_constant_evaluated instead of built-in, or remove check
entirely.
* include/std/array (operator<=>): Use __is_constant_evaluated
unconditionally.
* include/std/bit (__bit_ceil): Likewise.
* include/std/type_traits (is_constant_evaluated): Define using
'if consteval' if possible.
* include/std/version: Use new macro.
* libsupc++/compare: Use __is_constant_evaluated instead of
__builtin_is_constant_evaluated.
* testsuite/23_containers/array/tuple_interface/get_neg.cc:
Adjust dg-error lines.
The r179236 fix for std::type_info::operator== should also have been
applied to std::type_info::before. Otherwise two distinct types can
compare equivalent due to using a string comparison, when they should do
a pointer comparison.
libstdc++-v3/ChangeLog:
PR libstdc++/103240
* libsupc++/tinfo2.cc (type_info::before): Use unadjusted name
to check for the '*' prefix.
* testsuite/util/testsuite_shared.cc: Add type_info object for
use in new test.
* testsuite/18_support/type_info/103240.cc: New test.
These functions have been deprecated since C++11, and were removed in
C++17. The proposal P0323 wants to reuse the name std::unexpected for a
class template, so we will need to stop defining the current function
for C++23 anyway.
This marks them as deprecated for C++11 and up, to warn users they won't
continue to be available. It disables them for C++17 and up, unless the
_GLIBCXX_USE_DEPRECATED macro is defined.
The <unwind-cxx.h> header uses std::unexpected_handler in the public
API, but since that type is the same as std::terminate_handler we can
just use that instead, to avoid warnings about it being deprecated.
libstdc++-v3/ChangeLog:
* doc/xml/manual/evolution.xml: Document deprecations.
* doc/html/*: Regenerate.
* libsupc++/exception (unexpected_handler, unexpected)
(get_unexpected, set_unexpected): Add deprecated attribute.
Do not define without _GLIBCXX_USE_DEPRECATED for C++17 and up.
* libsupc++/eh_personality.cc (PERSONALITY_FUNCTION): Disable
deprecated warnings.
* libsupc++/eh_ptr.cc (std::rethrow_exception): Likewise.
* libsupc++/eh_terminate.cc: Likewise.
* libsupc++/eh_throw.cc (__cxa_init_primary_exception):
Likewise.
* libsupc++/unwind-cxx.h (struct __cxa_exception): Use
terminate_handler instead of unexpected_handler.
(struct __cxa_dependent_exception): Likewise.
(__unexpected): Likewise.
* testsuite/18_support/headers/exception/synopsis.cc: Add
dg-warning for deprecated warning.
* testsuite/18_support/exception_ptr/60612-unexpected.cc:
Disable deprecated warnings.
* testsuite/18_support/set_unexpected.cc: Likewise.
* testsuite/18_support/unexpected_handler.cc: Likewise.
gcc/testsuite/ChangeLog:
* g++.dg/cpp0x/lambda/lambda-eh2.C: Add dg-warning for new
deprecation warnings.
* g++.dg/cpp0x/noexcept06.C: Likewise.
* g++.dg/cpp0x/noexcept07.C: Likewise.
* g++.dg/eh/forced3.C: Likewise.
* g++.dg/eh/unexpected1.C: Likewise.
* g++.old-deja/g++.eh/spec1.C: Likewise.
* g++.old-deja/g++.eh/spec2.C: Likewise.
* g++.old-deja/g++.eh/spec3.C: Likewise.
* g++.old-deja/g++.eh/spec4.C: Likewise.
* g++.old-deja/g++.mike/eh33.C: Likewise.
* g++.old-deja/g++.mike/eh34.C: Likewise.
* g++.old-deja/g++.mike/eh50.C: Likewise.
* g++.old-deja/g++.mike/eh51.C: Likewise.
This adds an inline wrapper for std::terminate that doesn't add the
declaration of std::terminate to namespace std. This allows the
library to terminate without including all of <exception>.
libstdc++-v3/ChangeLog:
* include/bits/atomic_timed_wait.h: Remove unused header.
* include/bits/c++config (std:__terminate): Define.
* include/bits/semaphore_base.h: Remove <exception> and use
__terminate instead of terminate.
* include/bits/std_thread.h: Likewise.
* libsupc++/eh_terminate.cc (std::terminate): Use qualified-id
to call __cxxabiv1::__terminate.
