[PATCHv3] libstdc++: Use allocate_at_least in vector, string (P0401) [PR118030]
Nathan Myers
ncm@cantrip.org
Wed Apr 22 04:16:50 GMT 2026
[This patch retains the added config/abi/pre/gnu.ver string
symbol exports as if for gcc-16, although the planned ship
vehicle is gcc-17.]
Changes in v3:
- Make allocator_traits<allocator<T>>::allocate_at_least
call allocator<T>::allocate_at_least directly, no checking
needed.
- Remove __allocate_to_alignment helper from alloc_traits.h,
folding it back into __new_allocator::allocate_at_least.
Replace use of std::rotl with op>>, saving one instruction
on x86.
- Change "if (is_constant_evaluated())" to "if consteval {"
where allowed. This required infelicitous changes to
indentation because, in "if consteval ... else {", the
bracket is (needlessly) required.
- Remove second, "hint" argument passed to allocate()
in fallback from allocator_traits<>::allocate_at_least,
as support for that has been deleted from the Standard.
- Remove attempt at pass-through from allocator_traits<
pmr::polymorphic_allocator>::allocate_at_least because
it does not provide that, and just call allocate(n).
- Retain minimalist vector<>::_M_allocate, used mainly
to get storage for vector<bool>.
- Rename new vector helper members _M_displace_storage
-> _M_replace_storage, and _M_allocate_and_migrate ->
_M_replace_with.
- Remove __glibcxx_want_allocate_at_least from <vector>
and <string> headers.
- Whitespace fixups.
Changes in v2:
- Avoid PR108377 "exceeds maximum object size" warning
differently, contained to __allocate_to_alignment.
- Rename _S_allocate_to_alignment to __allocate_to_alignment
because it is not a member. Generalize it for arbitrary pointer
and size types.
- Declare allocator_traits<allocator<void>>::allocate_at_least
with " = delete;", matching others.
- In allocator_traits<>::allocate_at_least, de-structure and
reconstruct the allocation result to enable an implicit
pointer type conversion on the way, as used (e.g.) for
testsuite_allocator.h.
- Define allocate_at_least in the polymorphic specialization
of allocator_traits (bits/memory_resource.h), and in the
testsuite allocator, destructuring likewise.
- In string:
- Make _M_create use _M_allocate_at_least. (This function
is no longer used, but is retained for ABI stability.)
- Define (in addition to _M_create_plus) a new allocation
helper function _M_create_and_place to abstract common
operations, and use it where suitable.
- Add new member signatures to config/abi/pre/gnu.ver.
- Relax shrink_to_fit()/reserve() to allow a little extra.
- In vector, define (on top of _S_allocate_at_least) helper
functions _M_allocate_and_copy, _M_displace_storage,
and _M_allocate_and_migrate to abstract common ops, and
use them. This incidentally corrects an omission of a
_GLIBCXX_ASAN_ANNOTATE_REINIT.
- Adjust tests to pass with or without allocate_at_least.
(__STDCPP_DEFAULT_NEW_ALIGNMENT__ is not defined everywhere.)
Changes from RFC:
- Improve doxygen for new interfaces.
- Move code implementing alignment size-round-up logic from
allocator.h to alloc_traits.h for other allocators' reuse.
- Restore allocator.h definition of allocate_at_least, that
then explicitly delegates to its base class implementation.
- Retain existing string::_S_allocate, vector<>::_M_allocate
interfaces for ABI stability, using new names
_S_allocate_at_least, _M_allocate_at_least for new behavior.
- Define string _M_create_plus using S_allocate_at_least, and
use that throughout in place of _M_create, retaining _M_create
for ABI stability.
- Make memory_resource::allocate_at_least use argument
allocator's allocate_at_least if present.
- Fix std::allocator<>::allocate_at_least so it takes its
allocator object by reference, not by value.
- Per review, in constexpr context begin lifetime of all
potential string characters upon allocation.
- Revert "< 2011"-only vector<>::_M_initialize_dispatch changes.
- Fix string new-capacity off-by-one errors.
- Export new symbols _S_allocate_at_least and _M_create_plus from
bits/basic_string.h.
- Work around PR108377 spurious "exceeds maximum object size".
- Test.
- Patch too-strict capacity tests.
Implements as much of `allocator<>::allocate_at_least` as possible
relying solely on known alignment behavior of standard operator
new.
Uses `allocator_at_least` in `string` and `vector` to maximize
usage of actually allocated storage, as revealed by the
allocator in use. For user-supplied allocators this may make a
big difference.
Nothing is changed in `include/ext/malloc_allocator.h` or
others. They can be updated piecemeal. C++23 and C++26 do not
support `allocate_at_least` in `pmr` components, so there are
only minimal changes there.
libstdc++-v3/ChangeLog:
PR libstdc++/118030
* include/bits/alloc_traits.h:
(__allocate_to_alignment): Define.
(allocate_at_least): In allocator_traits template member,
destructure and reconstruct result from allocator object's version,
to enable pointer type conversion.
(allocate_at_least): Delegate in allocator_traits<allocator<_Tp>>
specialization to allocator<_Tp>::allocate_at_least, unconditionally.
(allocate_at_least): Declare "= delete;" in allocator<void>.
* include/bits/allocator.h (allocate_at_least): Delegate to base
allocate_at_least where defined, calling with explicit base-class
qualification, picking up __new_allocator member.
* include/bits/basic_string.h:
(_Alloc_result): Define new type.
(_S_allocate_at_least): Define.
(_S_allocate): Delegate to _S_allocate_at_least.
(_M_create_plus, _M_create_and_place): Declare.
(assign): Use _S_allocate_at_least.
* include/bits/basic_string.tcc:
(_M_create_plus): Define.
(_M_create_and_place): Define, abstracting common operations.
(_M_replace, reserve): Use _S_allocate_at_least.
(_M_construct, input iterators): Use _M_create_plus.
(_M_construct, others (3x)): Use _M_create_and_place.
(_M_create, _M_assign, reserve, _M_mutate): Use _M_create_plus.
* include/bits/memory_resource.h (allocate_at_least): Define,
document.
* include/bits/new_allocator.h (allocate_at_least): Define, relying
on __allocate_to_alignment from alloc_traits.h.
(deallocate): Refine "if constexpr" logic.
* include/bits/stl_vector.h:
(_S_max_size): Move to _Vector_base.
(_Alloc_result): Define type.
(_M_allocate_at_least): Define, using allocate_at_least where supported.
(_M_allocate): Delegate to _M_allocate_at_least.
(max_size, _S_check_init_len): Use _S_max_size as moved.
(_M_create_storage, append_range, _M_allocate_and_copy,
_M_replace_storage): Define, abstracting common operations.
(_M_replace_with): Define, likewise.
(_M_range_initialize_n): Use _M_allocate_at_least.
(_M_check_len): Improve logic.
* include/bits/vector.tcc:
(reserve, _M_fill_append, _M_range_insert): Use _M_allocate_at_least
and _M_replace_storage.
(operator=, _M_assign_aux): Use _M_replace_with.
(_M_realloc_insert, _M_realloc_append, _M_default_append, insert_range):
Use _M_allocate_at_least.
(_M_fill_insert): Use _M_replace_storage, normalize whitespace.
* testsuite/util/testsuite_allocator.h:
(allocate_at_least (2x)): Define.
(allocate): Use allocate_at_least.
* testsuite/20_util/allocator/allocate_at_least.cc: Add tests.
* testsuite/21_strings/basic_string/capacity/char/18654.cc:
Loosen capacity check.
* testsuite/21_strings/basic_string/capacity/char/shrink_to_fit.cc:
Same.
* testsuite/21_strings/basic_string/capacity/wchar_t/18654.cc: Same.
* testsuite/21_strings/basic_string/capacity/wchar_t/2.cc: Same.
* testsuite/21_strings/basic_string/capacity/wchar_t/shrink_to_fit.cc:
Same.
* testsuite/23_containers/vector/capacity/shrink_to_fit.cc: Same.
* testsuite/23_containers/vector/capacity/shrink_to_fit2.cc: Same
* testsuite/23_containers/vector/modifiers/emplace/self_emplace.cc:
Adapt to looser reserve behavior.
* config/abi/pre/gnu.ver: Expose string::_S_allocate_at_least,
_M_create_plus, and _M_create_and_place symbols.
---
libstdc++-v3/config/abi/pre/gnu.ver | 4 +
libstdc++-v3/include/bits/alloc_traits.h | 24 ++-
libstdc++-v3/include/bits/allocator.h | 31 +++-
libstdc++-v3/include/bits/basic_string.h | 43 ++++-
libstdc++-v3/include/bits/basic_string.tcc | 105 +++++++-----
libstdc++-v3/include/bits/memory_resource.h | 17 ++
libstdc++-v3/include/bits/new_allocator.h | 60 ++++++-
libstdc++-v3/include/bits/stl_vector.h | 138 ++++++++++++----
libstdc++-v3/include/bits/vector.tcc | 155 +++++++-----------
.../20_util/allocator/allocate_at_least.cc | 108 +++++++++++-
.../basic_string/capacity/char/18654.cc | 7 +-
.../capacity/char/shrink_to_fit.cc | 7 +-
.../basic_string/capacity/wchar_t/18654.cc | 8 +-
.../basic_string/capacity/wchar_t/2.cc | 13 +-
.../capacity/wchar_t/shrink_to_fit.cc | 7 +-
.../vector/capacity/shrink_to_fit.cc | 7 +-
.../vector/capacity/shrink_to_fit2.cc | 14 +-
.../vector/modifiers/emplace/self_emplace.cc | 36 ++--
.../testsuite/util/testsuite_allocator.h | 36 ++++
19 files changed, 594 insertions(+), 226 deletions(-)
diff --git a/libstdc++-v3/config/abi/pre/gnu.ver b/libstdc++-v3/config/abi/pre/gnu.ver
index bd4da641829..5dc9e1fdace 100644
--- a/libstdc++-v3/config/abi/pre/gnu.ver
+++ b/libstdc++-v3/config/abi/pre/gnu.ver
@@ -2621,6 +2621,10 @@ GLIBCXX_3.4.35 {
_ZGIW3std;
_ZGIW3stdW6compat;
+ # basic_string::allocate_at_least
+ _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE*_S_allocate_*;
+ _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE*_M_create_*;
+
} GLIBCXX_3.4.34;
# Symbols in the support library (libsupc++) have their own tag.
diff --git a/libstdc++-v3/include/bits/alloc_traits.h b/libstdc++-v3/include/bits/alloc_traits.h
index e4e0f1608de..cdffeb1b31a 100644
--- a/libstdc++-v3/include/bits/alloc_traits.h
+++ b/libstdc++-v3/include/bits/alloc_traits.h
@@ -419,10 +419,14 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
*/
[[nodiscard]] static constexpr auto
allocate_at_least(_Alloc& __a, size_type __n)
- -> allocation_result<pointer, size_type>
+ -> allocation_result<pointer, size_type>
{
if constexpr (requires { __a.allocate_at_least(__n); })
- return __a.allocate_at_least(__n);
+ {
+ // Destructure to enable implicit __p -> pointer conversion.
+ auto [__p, __c] = __a.allocate_at_least(__n);
+ return { __p, __c };
+ }
else
return { __a.allocate(__n), __n };
}
@@ -664,14 +668,15 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
* @brief Allocate memory, generously.
* @param __a An allocator.
* @param __n The minimum number of objects to allocate space for.
- * @return Memory of suitable size and alignment for `n` or more
- * contiguous objects of type `value_type`.
+ * @return Memory of suitable size and alignment for `m >= n`
+ * contiguous objects of type `value_type`, and `m`.
*
* Returns `a.allocate_at_least(n)`.
*/
- [[nodiscard]] static constexpr auto
+ [[nodiscard,__gnu__::__always_inline__]]
+ static constexpr auto
allocate_at_least(allocator_type& __a, size_type __n)
- -> allocation_result<pointer, size_type>
+ -> allocation_result<pointer, size_type>
{ return __a.allocate_at_least(__n); }
#endif
@@ -822,6 +827,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
static void*
allocate(allocator_type&, size_type, const void* = nullptr) = delete;
+#ifdef __glibcxx_allocate_at_least
+ static allocation_result<pointer, size_type>
+ allocate_at_least(allocator_type&, size_type) = delete;
+#endif
+
/// deallocate is ill-formed for allocator<void>
static void
deallocate(allocator_type&, void*, size_type) = delete;
@@ -872,7 +882,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
select_on_container_copy_construction(const allocator_type& __rhs)
{ return __rhs; }
};
-#endif
+#endif // _GLIBCXX_HOSTED
/// @cond undocumented
#pragma GCC diagnostic push
diff --git a/libstdc++-v3/include/bits/allocator.h b/libstdc++-v3/include/bits/allocator.h
index 9c22c805ebe..adf9f4fddbf 100644
--- a/libstdc++-v3/include/bits/allocator.h
+++ b/libstdc++-v3/include/bits/allocator.h
@@ -193,9 +193,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
constexpr _Tp*
allocate(size_t __n)
{
-#if __cpp_concepts
+# if __cpp_concepts
if constexpr (requires { sizeof(_Tp); })
-#endif
+# endif
if (std::__is_constant_evaluated())
{
if (__builtin_mul_overflow(__n, sizeof(_Tp), &__n))
@@ -205,7 +205,28 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
return __allocator_base<_Tp>::allocate(__n, 0);
}
+#endif
+
+#ifdef __glibcxx_allocate_at_least // C++23
+ [[nodiscard,__gnu__::__always_inline__]]
+ constexpr auto
+ allocate_at_least(size_t __n)
+ -> allocation_result<_Tp*, size_t>
+ {
+ if consteval
+ { return { allocate(__n), __n }; }
+ else
+ {
+ if constexpr (requires
+ { __allocator_base<_Tp>::allocate_at_least(__n); })
+ return __allocator_base<_Tp>::allocate_at_least(__n);
+ else
+ return { __allocator_base<_Tp>::allocate(__n), __n };
+ }
+ }
+#endif
+#if __cpp_constexpr_dynamic_alloc // >= C++20
[[__gnu__::__always_inline__]]
constexpr void
deallocate(_Tp* __p, size_t __n)
@@ -219,12 +240,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
#endif // C++20
-#ifdef __glibcxx_allocate_at_least // C++23
- [[nodiscard]] constexpr allocation_result<_Tp*, size_t>
- allocate_at_least(size_t __n)
- { return { this->allocate(__n), __n }; }
-#endif
-
friend __attribute__((__always_inline__)) _GLIBCXX20_CONSTEXPR
bool
operator==(const allocator&, const allocator&) _GLIBCXX_NOTHROW
diff --git a/libstdc++-v3/include/bits/basic_string.h b/libstdc++-v3/include/bits/basic_string.h
index af4e5d9486f..7ba2d60b644 100644
--- a/libstdc++-v3/include/bits/basic_string.h
+++ b/libstdc++-v3/include/bits/basic_string.h
@@ -135,20 +135,36 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
#endif
private:
+ // For ABI reasons this must remain. In current code, it
+ // is used only in constexpr context.
static _GLIBCXX20_CONSTEXPR pointer
_S_allocate(_Char_alloc_type& __a, size_type __n)
+ { return _S_allocate_at_least(__a, __n).__ptr; }
+
+ struct _Alloc_result { pointer __ptr; size_type __count; };
+
+ static _GLIBCXX20_CONSTEXPR _Alloc_result
+ _S_allocate_at_least(_Char_alloc_type& __a, size_type __n)
{
- pointer __p = _Alloc_traits::allocate(__a, __n);
-#if __glibcxx_constexpr_string >= 201907L
+ _Alloc_result __r;
+#ifdef __glibcxx_allocate_at_least // C++23
+ auto [__ptr, __count] = _Alloc_traits::allocate_at_least(__a, __n);
+ __r.__ptr = __ptr;
+ __r.__count = __count;
+#else
+ __r.__ptr = _Alloc_traits::allocate(__a, __n);
+ __r.__count = __n;
+#endif
+# if __glibcxx_constexpr_string >= 201907L
// std::char_traits begins the lifetime of characters,
// but custom traits might not, so do it here.
if constexpr (!is_same_v<_Traits, char_traits<_CharT>>)
if (std::__is_constant_evaluated())
// Begin the lifetime of characters in allocated storage.
- for (size_type __i = 0; __i < __n; ++__i)
- std::construct_at(__builtin_addressof(__p[__i]));
-#endif
- return __p;
+ for (size_type __i = 0; __i < __r.__count; ++__i)
+ std::construct_at(__builtin_addressof(__r.__ptr[__i]));
+# endif
+ return __r;
}
#ifdef __glibcxx_string_view // >= C++17
@@ -287,6 +303,15 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
// Create & Destroy
_GLIBCXX20_CONSTEXPR
+ _Alloc_result
+ _M_create_plus(size_type __new_capacity, size_type __old_capacity);
+
+ _GLIBCXX20_CONSTEXPR
+ void
+ _M_create_and_place(size_type __new_capacity, size_type __old_capacity);
+
+ // This must remain for ABI stability though unused.
+ _GLIBCXX20_CONSTEXPR
pointer
_M_create(size_type&, size_type);
@@ -1782,10 +1807,10 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
const auto __len = __str.size();
auto __alloc = __str._M_get_allocator();
// If this allocation throws there are no effects:
- auto __ptr = _S_allocate(__alloc, __len + 1);
+ auto __r = _S_allocate_at_least(__alloc, __len + 1);
_M_destroy(_M_allocated_capacity);
- _M_data(__ptr);
- _M_capacity(__len);
+ _M_data(__r.__ptr);
+ _M_capacity(__r.__count - 1);
_M_set_length(__len);
}
}
diff --git a/libstdc++-v3/include/bits/basic_string.tcc b/libstdc++-v3/include/bits/basic_string.tcc
index b00dd550237..1be0a1b3791 100644
--- a/libstdc++-v3/include/bits/basic_string.tcc
+++ b/libstdc++-v3/include/bits/basic_string.tcc
@@ -139,14 +139,14 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
template<typename _CharT, typename _Traits, typename _Alloc>
_GLIBCXX20_CONSTEXPR
- typename basic_string<_CharT, _Traits, _Alloc>::pointer
+ typename basic_string<_CharT, _Traits, _Alloc>::_Alloc_result
basic_string<_CharT, _Traits, _Alloc>::
- _M_create(size_type& __capacity, size_type __old_capacity)
+ _M_create_plus(size_type __capacity, size_type __old_capacity)
{
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 83. String::npos vs. string::max_size()
if (__capacity > max_size())
- std::__throw_length_error(__N("basic_string::_M_create"));
+ std::__throw_length_error(__N("basic_string::_M_create_plus"));
// The below implements an exponential growth policy, necessary to
// meet amortized linear time requirements of the library: see
@@ -161,7 +161,31 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
// NB: Need an array of char_type[__capacity], plus a terminating
// null char_type() element.
- return _S_allocate(_M_get_allocator(), __capacity + 1);
+ return _S_allocate_at_least(_M_get_allocator(), __capacity + 1);
+ }
+
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ _GLIBCXX20_CONSTEXPR
+ void
+ basic_string<_CharT, _Traits, _Alloc>::
+ _M_create_and_place(size_type __capacity, size_type __old_capacity)
+ {
+ _Alloc_result __r = _M_create_plus(__capacity, __old_capacity);
+ _M_data(__r.__ptr);
+ _M_capacity(__r.__count - 1); // Leave room for NUL.
+ }
+
+ // This must remain for ABI stability, though unused in current code.
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ _GLIBCXX20_CONSTEXPR
+ typename basic_string<_CharT, _Traits, _Alloc>::pointer
+ basic_string<_CharT, _Traits, _Alloc>::
+ _M_create(size_type& __capacity, size_type __old_capacity)
+ {
+ _Alloc_result __r = _M_create_plus(__capacity, __old_capacity);
+ __capacity = __r.__count - 1; // Leave room for NUL.
+ return __r.__ptr;
}
// NB: This is the special case for Input Iterators, used in
@@ -203,11 +227,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
if (__len == __capacity)
{
// Allocate more space.
- __capacity = __len + 1;
- pointer __another = _M_create(__capacity, __len);
- this->_S_copy(__another, _M_data(), __len);
+ _Alloc_result __another = _M_create_plus(__len + 1, __len);
+ __capacity = __another.__count - 1; // Leave room for NUL.
+ this->_S_copy(__another.__ptr, _M_data(), __len);
_M_dispose();
- _M_data(__another);
+ _M_data(__another.__ptr);
_M_capacity(__capacity);
}
traits_type::assign(_M_data()[__len++],
@@ -231,10 +255,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
size_type __dnew = static_cast<size_type>(std::distance(__beg, __end));
if (__dnew > size_type(_S_local_capacity))
- {
- _M_data(_M_create(__dnew, size_type(0)));
- _M_capacity(__dnew);
- }
+ _M_create_and_place(__dnew, size_type(0));
else
_M_init_local_buf();
@@ -264,10 +285,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
_M_construct(size_type __n, _CharT __c)
{
if (__n > size_type(_S_local_capacity))
- {
- _M_data(_M_create(__n, size_type(0)));
- _M_capacity(__n);
- }
+ _M_create_and_place(__n, size_type(0));
else
_M_init_local_buf();
@@ -281,16 +299,13 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
// than difference between iterators.
template<typename _CharT, typename _Traits, typename _Alloc>
template<bool _Terminated>
- _GLIBCXX20_CONSTEXPR
+ _GLIBCXX20_CONSTEXPR
void
basic_string<_CharT, _Traits, _Alloc>::
_M_construct(const _CharT* __str, size_type __n)
{
if (__n > size_type(_S_local_capacity))
- {
- _M_data(_M_create(__n, size_type(0)));
- _M_capacity(__n);
- }
+ _M_create_and_place(__n, size_type(0));
else
_M_init_local_buf();
@@ -347,11 +362,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
if (__rsize > __capacity)
{
- size_type __new_capacity = __rsize;
- pointer __tmp = _M_create(__new_capacity, __capacity);
+ // if _M_create_plus throws, there is no effect.
+ _Alloc_result __tmp = _M_create_plus(__rsize, __capacity);
_M_dispose();
- _M_data(__tmp);
- _M_capacity(__new_capacity);
+ _M_data(__tmp.__ptr);
+ _M_capacity(__tmp.__count - 1);
}
if (__rsize)
@@ -375,11 +390,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
if (__res <= __capacity)
return;
- pointer __tmp = _M_create(__res, __capacity);
- this->_S_copy(__tmp, _M_data(), length() + 1);
+ _Alloc_result __r = _M_create_plus(__res, __capacity);
+ this->_S_copy(__r.__ptr, _M_data(), length() + 1);
_M_dispose();
- _M_data(__tmp);
- _M_capacity(__res);
+ _M_data(__r.__ptr);
+ _M_capacity(__r.__count - 1); // Leave room for NUL.
}
template<typename _CharT, typename _Traits, typename _Alloc>
@@ -392,19 +407,19 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
const size_type __how_much = length() - __pos - __len1;
size_type __new_capacity = length() + __len2 - __len1;
- pointer __r = _M_create(__new_capacity, capacity());
+ _Alloc_result __r = _M_create_plus(__new_capacity, capacity());
if (__pos)
- this->_S_copy(__r, _M_data(), __pos);
+ this->_S_copy(__r.__ptr, _M_data(), __pos);
if (__s && __len2)
- this->_S_copy(__r + __pos, __s, __len2);
+ this->_S_copy(__r.__ptr + __pos, __s, __len2);
if (__how_much)
- this->_S_copy(__r + __pos + __len2,
+ this->_S_copy(__r.__ptr + __pos + __len2,
_M_data() + __pos + __len1, __how_much);
_M_dispose();
- _M_data(__r);
- _M_capacity(__new_capacity);
+ _M_data(__r.__ptr);
+ _M_capacity(__r.__count - 1); // Leave room for NUL.
}
template<typename _CharT, typename _Traits, typename _Alloc>
@@ -430,6 +445,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
if (_M_is_local())
return;
+# ifdef __glibcxx_allocate_at_least // C++23
+ const size_type __limit = (__STDCPP_DEFAULT_NEW_ALIGNMENT__ - 1) / sizeof(_CharT);
+# else
+ const size_type __limit = 0;
+# endif
const size_type __length = length();
const size_type __capacity = _M_allocated_capacity;
@@ -441,14 +461,15 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
_M_data(_M_local_data());
}
#if __cpp_exceptions
- else if (__length < __capacity)
+ else if (__capacity - __length > __limit )
try
{
- pointer __tmp = _S_allocate(_M_get_allocator(), __length + 1);
- this->_S_copy(__tmp, _M_data(), __length + 1);
+ _Alloc_result __r = _S_allocate_at_least(
+ _M_get_allocator(), __length + 1);
+ this->_S_copy(__r.__ptr, _M_data(), __length + 1);
_M_dispose();
- _M_data(__tmp);
- _M_capacity(__length);
+ _M_data(__r.__ptr);
+ _M_capacity(__r.__count - 1); // reserve room for NUL.
}
catch (const __cxxabiv1::__forced_unwind&)
{ throw; }
@@ -677,7 +698,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
#endif // C++11
#endif // _GLIBCXX_USE_CXX11_ABI
-
+
#if __glibcxx_constexpr_string >= 201907L
# define _GLIBCXX_STRING_CONSTEXPR constexpr
#else
@@ -916,7 +937,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
// Avoid reallocation for common case.
__str.erase();
_CharT __buf[128];
- __size_type __len = 0;
+ __size_type __len = 0;
const streamsize __w = __in.width();
const __size_type __n = __w > 0 ? static_cast<__size_type>(__w)
: __str.max_size();
diff --git a/libstdc++-v3/include/bits/memory_resource.h b/libstdc++-v3/include/bits/memory_resource.h
index e5c6697b07e..cb29ff88478 100644
--- a/libstdc++-v3/include/bits/memory_resource.h
+++ b/libstdc++-v3/include/bits/memory_resource.h
@@ -48,6 +48,7 @@
# include <bits/utility.h> // index_sequence
# include <tuple> // tuple, forward_as_tuple
#endif
+#include <bits/memoryfwd.h>
namespace std _GLIBCXX_VISIBILITY(default)
{
@@ -468,6 +469,22 @@ namespace pmr
allocate(allocator_type& __a, size_type __n, const_void_pointer)
{ return __a.allocate(__n); }
+#ifdef __glibcxx_allocate_at_least
+ /**
+ * @brief Allocate memory, generously.
+ * @param __a An allocator.
+ * @param __n The number of objects to allocate space for.
+ * @return Memory of suitable size and alignment for `m >= n`
+ * objects of type `value_type`, and `m`.
+ *
+ * Returns `{ a.allocate(n), n }`.
+ */
+ [[nodiscard]] static auto
+ allocate_at_least(allocator_type& __a, size_type __n)
+ -> std::allocation_result<pointer, size_type>
+ { return { __a.allocate(__n), __n }; }
+#endif
+
/**
* @brief Deallocate memory.
* @param __a An allocator.
diff --git a/libstdc++-v3/include/bits/new_allocator.h b/libstdc++-v3/include/bits/new_allocator.h
index fbe03e392aa..1ce2d41388f 100644
--- a/libstdc++-v3/include/bits/new_allocator.h
+++ b/libstdc++-v3/include/bits/new_allocator.h
@@ -37,6 +37,7 @@
#if __cplusplus >= 201103L
#include <type_traits>
#endif
+#include <bits/memoryfwd.h>
namespace std _GLIBCXX_VISIBILITY(default)
{
@@ -150,6 +151,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
std::__throw_bad_array_new_length();
std::__throw_bad_alloc();
}
+
#if __cpp_aligned_new && __cplusplus >= 201103L
else if constexpr (alignof(_Tp) > __STDCPP_DEFAULT_NEW_ALIGNMENT__)
{
@@ -162,6 +164,60 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
return static_cast<_Tp*>(_GLIBCXX_OPERATOR_NEW(__n * sizeof(_Tp)));
}
+#ifdef __glibcxx_allocate_at_least // C++23
+ [[nodiscard]] constexpr auto
+ allocate_at_least(size_t __n)
+ -> std::allocation_result<_Tp*, size_t>
+ {
+ static_assert(requires { sizeof(_Tp); },
+ "cannot allocate incomplete types");
+
+ if constexpr (!requires { sizeof(_Tp); })
+ return { nullptr, 0 }; // static_assert already failed
+ else if (__builtin_expect(__n > this->_M_max_size(), false))
+ {
+ // _GLIBCXX_RESOLVE_LIB_DEFECTS
+ // 3190. allocator::allocate sometimes returns too little storage
+ if (__n > (std::size_t(-1) / sizeof(_Tp)))
+ std::__throw_bad_array_new_length();
+ std::__throw_bad_alloc();
+ }
+ else if consteval
+ {
+ void* __p = _GLIBCXX_OPERATOR_NEW(__n * sizeof(_Tp));
+ return { static_cast<_Tp*>(__p), __n };
+ }
+ else
+ { // "if consteval" demands a block here.
+ const size_t __need = __n * sizeof(_Tp);
+ if constexpr (alignof(_Tp) > __STDCPP_DEFAULT_NEW_ALIGNMENT__)
+ {
+ const std::align_val_t __al = std::align_val_t(alignof(_Tp));
+ void* __p = _GLIBCXX_OPERATOR_NEW(__need, __al);
+ return { static_cast<_Tp*>(__p), __n };
+ }
+ else if constexpr (sizeof(_Tp) >= __STDCPP_DEFAULT_NEW_ALIGNMENT__)
+ {
+ void* __p = _GLIBCXX_OPERATOR_NEW(__need);
+ return { static_cast<_Tp*>(__p), __n };
+ }
+ else
+ {
+ const size_t __mask = __STDCPP_DEFAULT_NEW_ALIGNMENT__ - 1;
+ size_t __ask = (__need + __mask) & ~__mask;
+ // Avoid rounding to and asking for 2^63 bytes (PR108377):
+ __ask -= __ask >> (__SIZE_WIDTH__ - 1);
+ auto* __p = static_cast<_Tp*>(_GLIBCXX_OPERATOR_NEW(__ask));
+ using _U8 = const unsigned char;
+ static_assert(sizeof(_Tp) <= ~_U8());
+ // Use 8-bit division for minimal latency:
+ _U8 __spare = __ask - __need, __size = sizeof(_Tp);
+ return { __p , __n + __spare / __size };
+ }
+ }
+ }
+#endif
+
// __p is not permitted to be a null pointer.
_GLIBCXX20_CONSTEXPR void
deallocate(_Tp* __p, size_type __n __attribute__ ((__unused__)))
@@ -177,10 +233,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
{
_GLIBCXX_OPERATOR_DELETE(_GLIBCXX_SIZED_DEALLOC(__p, __n),
std::align_val_t(alignof(_Tp)));
- return;
}
+ else
#endif
- _GLIBCXX_OPERATOR_DELETE(_GLIBCXX_SIZED_DEALLOC(__p, __n));
+ _GLIBCXX_OPERATOR_DELETE(_GLIBCXX_SIZED_DEALLOC(__p, __n));
}
#pragma GCC diagnostic pop
diff --git a/libstdc++-v3/include/bits/stl_vector.h b/libstdc++-v3/include/bits/stl_vector.h
index c4ca214752a..5d7da03e2ee 100644
--- a/libstdc++-v3/include/bits/stl_vector.h
+++ b/libstdc++-v3/include/bits/stl_vector.h
@@ -317,6 +317,19 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
get_allocator() const _GLIBCXX_NOEXCEPT
{ return allocator_type(_M_get_Tp_allocator()); }
+ static _GLIBCXX20_CONSTEXPR size_t
+ _S_max_size(const _Tp_alloc_type& __a) _GLIBCXX_NOEXCEPT
+ {
+ // std::distance(begin(), end()) cannot be greater than PTRDIFF_MAX,
+ // and realistically we can't store more than PTRDIFF_MAX/sizeof(T)
+ // (even if std::allocator_traits::max_size says we can).
+ const size_t __diffmax =
+ __gnu_cxx::__numeric_traits<ptrdiff_t>::__max / sizeof(_Tp);
+ const size_t __allocmax =
+ __gnu_cxx::__alloc_traits<_Alloc>::max_size(__a);
+ return (std::min)(__diffmax, __allocmax);
+ }
+
#if __cplusplus >= 201103L
_Vector_base() = default;
#else
@@ -389,6 +402,43 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
return __n != 0 ? _Tr::allocate(_M_impl, __n) : pointer();
}
+ struct _Alloc_result { pointer __ptr; size_t __count; };
+
+ _GLIBCXX20_CONSTEXPR
+ _Alloc_result
+ _M_allocate_at_least(size_t __n)
+ {
+ typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Tr;
+ _Alloc_result __r;
+ if (__builtin_expect(__n != 0, true))
+ {
+#ifdef __glibcxx_allocate_at_least // C++23
+ if constexpr (requires { _Tr::allocate_at_least(_M_impl, __n); })
+ {
+ auto [__ptr, __count] = _Tr::allocate_at_least(_M_impl, __n);
+ if (__count > __n)
+ {
+ size_t __max = _S_max_size(_M_get_Tp_allocator());
+ if (__builtin_expect(__count > __max, false))
+ __count = __max;
+ }
+ __r = { __ptr, __count };
+ }
+ else
+#endif
+ {
+ __r.__ptr = _Tr::allocate(_M_impl, __n);
+ __r.__count = __n;
+ }
+ }
+ else
+ {
+ __r.__ptr = pointer();
+ __r.__count = 0;
+ }
+ return __r;
+ }
+
_GLIBCXX20_CONSTEXPR
void
_M_deallocate(pointer __p, size_t __n)
@@ -404,9 +454,9 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
void
_M_create_storage(size_t __n)
{
- this->_M_impl._M_start = this->_M_allocate(__n);
- this->_M_impl._M_finish = this->_M_impl._M_start;
- this->_M_impl._M_end_of_storage = this->_M_impl._M_start + __n;
+ _Alloc_result __r = this->_M_allocate_at_least(__n);
+ this->_M_impl._M_finish = this->_M_impl._M_start = __r.__ptr;
+ this->_M_impl._M_end_of_storage = this->_M_impl._M_start + __r.__count;
}
#if __glibcxx_containers_ranges // C++ >= 23
@@ -480,6 +530,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
typedef _Vector_base<_Tp, _Alloc> _Base;
typedef typename _Base::_Tp_alloc_type _Tp_alloc_type;
typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Alloc_traits;
+ typedef typename _Base::_Alloc_result _Alloc_result;
public:
typedef _Tp value_type;
@@ -536,6 +587,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
protected:
using _Base::_M_allocate;
+ using _Base::_M_allocate_at_least;
using _Base::_M_deallocate;
using _Base::_M_impl;
using _Base::_M_get_Tp_allocator;
@@ -1116,7 +1168,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
_GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
size_type
max_size() const _GLIBCXX_NOEXCEPT
- { return _S_max_size(_M_get_Tp_allocator()); }
+ { return _Base::_S_max_size(_M_get_Tp_allocator()); }
#if __cplusplus >= 201103L
/**
@@ -1682,16 +1734,17 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
return;
}
- const size_type __len = _M_check_len(__n, "vector::append_range");
+ const size_type __ask = _M_check_len(__n, "vector::append_range");
pointer __old_start = this->_M_impl._M_start;
pointer __old_finish = this->_M_impl._M_finish;
- allocator_type& __a = _M_get_Tp_allocator();
- const pointer __start = this->_M_allocate(__len);
+ auto [__ptr, __got] = this->_M_allocate_at_least(__ask);
+ const pointer __start = __ptr;
const pointer __mid = __start + __sz;
const pointer __back = __mid + __n;
- _Guard_alloc __guard(__start, __len, *this);
+ _Guard_alloc __guard(__start, __got, *this);
+ allocator_type& __a = _M_get_Tp_allocator();
std::__uninitialized_copy_a(ranges::begin(__rg),
ranges::end(__rg),
__mid, __a);
@@ -1733,7 +1786,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
// Finally, take ownership of new storage:
this->_M_impl._M_start = __start;
this->_M_impl._M_finish = __back;
- this->_M_impl._M_end_of_storage = __start + __len;
+ this->_M_impl._M_end_of_storage = __start + __got;
}
else
{
@@ -1889,20 +1942,45 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
protected:
/**
* Memory expansion handler. Uses the member allocation function to
- * obtain @a n bytes of memory, and then copies [first,last) into it.
+ * obtain at least `n` objects worth of memory, copies `[first,last)`
+ * into it, reports what was actually allocated.
*/
template<typename _ForwardIterator>
_GLIBCXX20_CONSTEXPR
- pointer
+ _Alloc_result
_M_allocate_and_copy(size_type __n,
- _ForwardIterator __first, _ForwardIterator __last)
+ _ForwardIterator __first, _ForwardIterator __last)
{
- _Guard_alloc __guard(this->_M_allocate(__n), __n, *this);
+ _Alloc_result __r = this->_M_allocate_at_least(__n);
+ _Guard_alloc __guard(__r.__ptr, __r.__count, *this);
std::__uninitialized_copy_a
(__first, __last, __guard._M_storage, _M_get_Tp_allocator());
- return __guard._M_release();
+ (void) __guard._M_release();
+ return __r;
}
+ _GLIBCXX20_CONSTEXPR void
+ _M_replace_storage(pointer __start, pointer __end, size_type __cap)
+ {
+ _GLIBCXX_ASAN_ANNOTATE_REINIT;
+ _M_deallocate(this->_M_impl._M_start,
+ this->_M_impl._M_end_of_storage - this->_M_impl._M_start);
+ this->_M_impl._M_start = __start;
+ this->_M_impl._M_finish = __end;
+ this->_M_impl._M_end_of_storage = __start + __cap;
+ }
+
+ template<typename _ForwardIterator>
+ _GLIBCXX20_CONSTEXPR
+ void
+ _M_replace_with(size_type __n,
+ _ForwardIterator __first, _ForwardIterator __last)
+ {
+ _Alloc_result __r = _M_allocate_and_copy(__n, __first, __last);
+ std::_Destroy(this->_M_impl._M_start,
+ this->_M_impl._M_finish, _M_get_Tp_allocator());
+ _M_replace_storage(__r.__ptr, __r.__ptr + __n, __r.__count);
+ }
// Internal constructor functions follow.
@@ -1916,6 +1994,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
_M_initialize_dispatch(_Integer __int_n, _Integer __value, __true_type)
{
const size_type __n = static_cast<size_type>(__int_n);
+ // NB this is c++98 code, so has no allocate_at_least.
pointer __start =
_M_allocate(_S_check_init_len(__n, _M_get_Tp_allocator()));
this->_M_impl._M_start = __start;
@@ -1971,10 +2050,11 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
_M_range_initialize_n(_Iterator __first, _Sentinel __last,
size_type __n)
{
- pointer __start =
- this->_M_allocate(_S_check_init_len(__n, _M_get_Tp_allocator()));
+ _Alloc_result __r = this->_M_allocate_at_least(
+ _S_check_init_len(__n, _M_get_Tp_allocator()));
+ pointer __start = __r.__ptr;
this->_M_impl._M_start = this->_M_impl._M_finish = __start;
- this->_M_impl._M_end_of_storage = __start + __n;
+ this->_M_impl._M_end_of_storage = __start + __r.__count;
this->_M_impl._M_finish
= std::__uninitialized_copy_a(_GLIBCXX_MOVE(__first), __last,
__start, _M_get_Tp_allocator());
@@ -2191,35 +2271,27 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
size_type
_M_check_len(size_type __n, const char* __s) const
{
- if (max_size() - size() < __n)
+ const size_type __room = max_size() - size();
+ if (__room < __n)
__throw_length_error(__N(__s));
- const size_type __len = size() + (std::max)(size(), __n);
- return (__len < size() || __len > max_size()) ? max_size() : __len;
+ if (__n < size())
+ __n = size(); // Grow by (at least) doubling ...
+ if (__n > __room)
+ __n = __room; // ... but only as much as will fit.
+ return size() + __n;
}
// Called by constructors to check initial size.
static _GLIBCXX20_CONSTEXPR size_type
_S_check_init_len(size_type __n, const allocator_type& __a)
{
- if (__n > _S_max_size(_Tp_alloc_type(__a)))
+ if (__n > _Base::_S_max_size(_Tp_alloc_type(__a)))
__throw_length_error(
__N("cannot create std::vector larger than max_size()"));
return __n;
}
- static _GLIBCXX20_CONSTEXPR size_type
- _S_max_size(const _Tp_alloc_type& __a) _GLIBCXX_NOEXCEPT
- {
- // std::distance(begin(), end()) cannot be greater than PTRDIFF_MAX,
- // and realistically we can't store more than PTRDIFF_MAX/sizeof(T)
- // (even if std::allocator_traits::max_size says we can).
- const size_t __diffmax
- = __gnu_cxx::__numeric_traits<ptrdiff_t>::__max / sizeof(_Tp);
- const size_t __allocmax = _Alloc_traits::max_size(__a);
- return (std::min)(__diffmax, __allocmax);
- }
-
// Internal erase functions follow.
// Called by erase(q1,q2), clear(), resize(), _M_fill_assign,
diff --git a/libstdc++-v3/include/bits/vector.tcc b/libstdc++-v3/include/bits/vector.tcc
index b790fca2964..86c41d74ff4 100644
--- a/libstdc++-v3/include/bits/vector.tcc
+++ b/libstdc++-v3/include/bits/vector.tcc
@@ -75,13 +75,13 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
if (this->capacity() < __n)
{
const size_type __old_size = size();
- pointer __tmp;
+ _Alloc_result __tmp;
#if __cplusplus >= 201103L
if constexpr (_S_use_relocate())
{
- __tmp = this->_M_allocate(__n);
+ __tmp = this->_M_allocate_at_least(__n);
std::__relocate_a(this->_M_impl._M_start, this->_M_impl._M_finish,
- __tmp, _M_get_Tp_allocator());
+ __tmp.__ptr, _M_get_Tp_allocator());
}
else
#endif
@@ -92,13 +92,8 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
std::_Destroy(this->_M_impl._M_start, this->_M_impl._M_finish,
_M_get_Tp_allocator());
}
- _GLIBCXX_ASAN_ANNOTATE_REINIT;
- _M_deallocate(this->_M_impl._M_start,
- this->_M_impl._M_end_of_storage
- - this->_M_impl._M_start);
- this->_M_impl._M_start = __tmp;
- this->_M_impl._M_finish = __tmp + __old_size;
- this->_M_impl._M_end_of_storage = this->_M_impl._M_start + __n;
+ _M_replace_storage(
+ __tmp.__ptr, __tmp.__ptr + __old_size, __tmp.__count);
}
}
#pragma GCC diagnostic pop
@@ -106,12 +101,12 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
#if __cplusplus >= 201103L
template<typename _Tp, typename _Alloc>
template<typename... _Args>
-#if __cplusplus > 201402L
+# if __cplusplus > 201402L
_GLIBCXX20_CONSTEXPR
typename vector<_Tp, _Alloc>::reference
-#else
+# else
void
-#endif
+# endif
vector<_Tp, _Alloc>::
emplace_back(_Args&&... __args)
{
@@ -125,11 +120,11 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
}
else
_M_realloc_append(std::forward<_Args>(__args)...);
-#if __cplusplus > 201402L
+# if __cplusplus > 201402L
return back();
-#endif
+# endif
}
-#endif
+#endif // __cplusplus >= 201103L
template<typename _Tp, typename _Alloc>
_GLIBCXX20_CONSTEXPR
@@ -238,22 +233,10 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
#endif
const size_type __xlen = __x.size();
if (__xlen > capacity())
- {
- pointer __tmp = _M_allocate_and_copy(__xlen, __x.begin(),
- __x.end());
- std::_Destroy(this->_M_impl._M_start, this->_M_impl._M_finish,
- _M_get_Tp_allocator());
- _M_deallocate(this->_M_impl._M_start,
- this->_M_impl._M_end_of_storage
- - this->_M_impl._M_start);
- this->_M_impl._M_start = __tmp;
- this->_M_impl._M_end_of_storage = this->_M_impl._M_start + __xlen;
- }
+ _M_replace_with(__xlen, __x.begin(), __x.end());
else if (size() >= __xlen)
- {
- std::_Destroy(std::copy(__x.begin(), __x.end(), begin()),
- end(), _M_get_Tp_allocator());
- }
+ std::_Destroy(std::copy(__x.begin(), __x.end(), begin()),
+ end(), _M_get_Tp_allocator());
else
{
std::copy(__x._M_impl._M_start, __x._M_impl._M_start + size(),
@@ -332,16 +315,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
__builtin_unreachable();
_S_check_init_len(__len, _M_get_Tp_allocator());
- pointer __tmp(_M_allocate_and_copy(__len, __first, __last));
- std::_Destroy(this->_M_impl._M_start, this->_M_impl._M_finish,
- _M_get_Tp_allocator());
- _GLIBCXX_ASAN_ANNOTATE_REINIT;
- _M_deallocate(this->_M_impl._M_start,
- this->_M_impl._M_end_of_storage
- - this->_M_impl._M_start);
- this->_M_impl._M_start = __tmp;
- this->_M_impl._M_finish = this->_M_impl._M_start + __len;
- this->_M_impl._M_end_of_storage = this->_M_impl._M_finish;
+ _M_replace_with(__len, __first, __last);
}
else if (__sz >= __len)
_M_erase_at_end(std::copy(__first, __last, this->_M_impl._M_start));
@@ -464,13 +438,15 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
_M_realloc_insert(iterator __position, const _Tp& __x)
#endif
{
- const size_type __len = _M_check_len(1u, "vector::_M_realloc_insert");
- if (__len <= 0)
+ const size_type __len1 = _M_check_len(1u, "vector::_M_realloc_insert");
+ if (__len1 <= 0)
__builtin_unreachable();
pointer __old_start = this->_M_impl._M_start;
pointer __old_finish = this->_M_impl._M_finish;
const size_type __elems_before = __position - begin();
- pointer __new_start(this->_M_allocate(__len));
+ _Alloc_result __r = this->_M_allocate_at_least(__len1);
+ const size_type __len = __r.__count;
+ pointer __new_start(__r.__ptr);
pointer __new_finish(__new_start);
{
@@ -574,14 +550,16 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
const size_type __len = _M_check_len(1u, "vector::_M_realloc_append");
if (__len <= 0)
__builtin_unreachable();
- pointer __old_start = this->_M_impl._M_start;
- pointer __old_finish = this->_M_impl._M_finish;
+ const pointer __old_start = this->_M_impl._M_start;
+ const pointer __old_finish = this->_M_impl._M_finish;
const size_type __elems = size();
- pointer __new_start(this->_M_allocate(__len));
+ const _Alloc_result __r = this->_M_allocate_at_least(__len);
+ const size_type __rlen = __r.__count;
+ const pointer __new_start(__r.__ptr);
pointer __new_finish(__new_start);
{
- _Guard_alloc __guard(__new_start, __len, *this);
+ _Guard_alloc __guard(__new_start, __rlen, *this);
// The order of the three operations is dictated by the C++11
// case, where the moves could alter a new element belonging
@@ -652,7 +630,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
this->_M_impl._M_start = __new_start;
this->_M_impl._M_finish = __new_finish;
- this->_M_impl._M_end_of_storage = __new_start + __len;
+ this->_M_impl._M_end_of_storage = __new_start + __rlen;
}
#pragma GCC diagnostic pop
@@ -716,10 +694,12 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
pointer __old_finish = this->_M_impl._M_finish;
const pointer __pos = __position.base();
- const size_type __len =
+ const size_type __len1 =
_M_check_len(__n, "vector::_M_fill_insert");
const size_type __elems_before = __pos - __old_start;
- pointer __new_start(this->_M_allocate(__len));
+ _Alloc_result __r = this->_M_allocate_at_least(__len1);
+ const size_type __len = __r.__count;
+ pointer __new_start(__r.__ptr);
pointer __new_finish(__new_start);
__try
{
@@ -727,21 +707,16 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
std::__uninitialized_fill_n_a(__new_start + __elems_before,
__n, __x,
_M_get_Tp_allocator());
- __new_finish = pointer();
-
- __new_finish
- = std::__uninitialized_move_if_noexcept_a
- (__old_start, __pos, __new_start, _M_get_Tp_allocator());
-
+ __new_finish = pointer(); // ... in case of a throw.
+ __new_finish = std::__uninitialized_move_if_noexcept_a(
+ __old_start, __pos, __new_start, _M_get_Tp_allocator());
__new_finish += __n;
-
- __new_finish
- = std::__uninitialized_move_if_noexcept_a
- (__pos, __old_finish, __new_finish, _M_get_Tp_allocator());
+ __new_finish = std::__uninitialized_move_if_noexcept_a(
+ __pos, __old_finish, __new_finish, _M_get_Tp_allocator());
}
__catch(...)
{
- if (!__new_finish)
+ if (__new_finish == pointer())
std::_Destroy(__new_start + __elems_before,
__new_start + __elems_before + __n,
_M_get_Tp_allocator());
@@ -752,12 +727,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
__throw_exception_again;
}
std::_Destroy(__old_start, __old_finish, _M_get_Tp_allocator());
- _GLIBCXX_ASAN_ANNOTATE_REINIT;
- _M_deallocate(__old_start,
- this->_M_impl._M_end_of_storage - __old_start);
- this->_M_impl._M_start = __new_start;
- this->_M_impl._M_finish = __new_finish;
- this->_M_impl._M_end_of_storage = __new_start + __len;
+ _M_replace_storage(__new_start, __new_finish, __len);
}
}
}
@@ -785,9 +755,10 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
pointer __old_finish = this->_M_impl._M_finish;
const size_type __old_size = __old_finish - __old_start;
- const size_type __len =
- _M_check_len(__n, "vector::_M_fill_append");
- pointer __new_start(this->_M_allocate(__len));
+ size_type __len = _M_check_len(__n, "vector::_M_fill_append");
+ _Alloc_result __r = this->_M_allocate_at_least(__len);
+ __len = __r.__count;
+ pointer __new_start(__r.__ptr);
pointer __new_finish(__new_start + __old_size);
__try
{
@@ -807,12 +778,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
__throw_exception_again;
}
std::_Destroy(__old_start, __old_finish, _M_get_Tp_allocator());
- _GLIBCXX_ASAN_ANNOTATE_REINIT;
- _M_deallocate(__old_start,
- this->_M_impl._M_end_of_storage - __old_start);
- this->_M_impl._M_start = __new_start;
- this->_M_impl._M_finish = __new_finish;
- this->_M_impl._M_end_of_storage = __new_start + __len;
+ _M_replace_storage(__new_start, __new_finish, __len);
}
}
@@ -852,9 +818,11 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
pointer __old_start = this->_M_impl._M_start;
pointer __old_finish = this->_M_impl._M_finish;
- const size_type __len =
+ const size_type __len1 =
_M_check_len(__n, "vector::_M_default_append");
- pointer __new_start(this->_M_allocate(__len));
+ _Alloc_result __r = this->_M_allocate_at_least(__len1);
+ const size_type __len = __r.__count;
+ pointer __new_start(__r.__ptr);
{
_Guard_alloc __guard(__new_start, __len, *this);
@@ -1003,14 +971,16 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
pointer __old_start = this->_M_impl._M_start;
pointer __old_finish = this->_M_impl._M_finish;
- const size_type __len =
+ const size_type __ask =
_M_check_len(__n, "vector::_M_range_insert");
#if __cplusplus < 201103L
- if (__len < (__n + (__old_finish - __old_start)))
+ if (__ask < (__n + (__old_finish - __old_start)))
__builtin_unreachable();
#endif
- pointer __new_start(this->_M_allocate(__len));
+ _Alloc_result __r = this->_M_allocate_at_least(__ask);
+ const size_type __got = __r.__count;
+ pointer __new_start(__r.__ptr);
pointer __new_finish(__new_start);
__try
{
@@ -1031,17 +1001,12 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
{
std::_Destroy(__new_start, __new_finish,
_M_get_Tp_allocator());
- _M_deallocate(__new_start, __len);
+ _M_deallocate(__new_start, __got);
__throw_exception_again;
}
std::_Destroy(__old_start, __old_finish,
_M_get_Tp_allocator());
- _GLIBCXX_ASAN_ANNOTATE_REINIT;
- _M_deallocate(__old_start,
- this->_M_impl._M_end_of_storage - __old_start);
- this->_M_impl._M_start = __new_start;
- this->_M_impl._M_finish = __new_finish;
- this->_M_impl._M_end_of_storage = __new_start + __len;
+ _M_replace_storage(__new_start, __new_finish, __got);
}
}
}
@@ -1111,7 +1076,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
}
else // Reallocate
{
- const size_type __len
+ const size_type __ask
= _M_check_len(__n, "vector::insert_range");
struct _Guard : _Guard_alloc
@@ -1130,8 +1095,10 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
};
// Allocate new storage:
- pointer __new_start(this->_M_allocate(__len));
- _Guard __guard(__new_start, __len, *this);
+ _Alloc_result __r = this->_M_allocate_at_least(__ask);
+ const size_type __got = __r.__count;
+ pointer __new_start(__r.__ptr);
+ _Guard __guard(__new_start, __got, *this);
auto& __alloc = _M_get_Tp_allocator();
@@ -1158,13 +1125,13 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
// with __guard so that it cleans up the old storage:
this->_M_impl._M_start = __guard._M_storage;
this->_M_impl._M_finish = __guard._M_finish;
- this->_M_impl._M_end_of_storage = __new_start + __len;
+ this->_M_impl._M_end_of_storage = __new_start + __got;
__guard._M_storage = __old_start;
__guard._M_finish = __old_finish;
__guard._M_len = (__old_finish - __old_start) + __cap;
// _Asan::_Reinit destructor marks unused capacity.
// _Guard destructor destroys [old_start,old_finish).
- // _Guard_alloc destructor frees [old_start,old_start+len).
+ // _Guard_alloc destructor frees [old_start,old_start+got).
}
return begin() + __ins_idx;
}
diff --git a/libstdc++-v3/testsuite/20_util/allocator/allocate_at_least.cc b/libstdc++-v3/testsuite/20_util/allocator/allocate_at_least.cc
index 5399096d294..987e2472490 100644
--- a/libstdc++-v3/testsuite/20_util/allocator/allocate_at_least.cc
+++ b/libstdc++-v3/testsuite/20_util/allocator/allocate_at_least.cc
@@ -29,7 +29,7 @@ template <typename T>
}
};
-int main()
+void base()
{
std::allocator<X> native;
auto a1 = native.allocate_at_least(100);
@@ -63,3 +63,109 @@ int main()
VERIFY(a5.ptr == minimal.keep);
minimal_traits::deallocate(minimal, a5.ptr, a5.count);
}
+
+void extra()
+{
+ using SatC = std::allocator_traits<std::allocator<char>>;
+ std::allocator<char> satc;
+ {
+ auto [p, n] = SatC::allocate_at_least(satc, 1);
+ VERIFY(n == __STDCPP_DEFAULT_NEW_ALIGNMENT__);
+ SatC::deallocate(satc, p, n);
+ }
+ {
+ auto [p, n] = SatC::allocate_at_least(satc, 2);
+ VERIFY(n == __STDCPP_DEFAULT_NEW_ALIGNMENT__);
+ SatC::deallocate(satc, p, n);
+ }
+ {
+ auto [p, n] =
+ SatC::allocate_at_least(satc, __STDCPP_DEFAULT_NEW_ALIGNMENT__ - 1);
+ VERIFY(n == __STDCPP_DEFAULT_NEW_ALIGNMENT__);
+ SatC::deallocate(satc, p, n);
+ }
+ {
+ auto [p, n] = SatC::allocate_at_least(
+ satc, __STDCPP_DEFAULT_NEW_ALIGNMENT__);
+ VERIFY(n == __STDCPP_DEFAULT_NEW_ALIGNMENT__);
+ SatC::deallocate(satc, p, n);
+ }
+
+ using SatS = std::allocator_traits<std::allocator<short>>;
+ std::allocator<short> sats;
+ {
+ auto [p, n] = SatS::allocate_at_least(sats, 1);
+ VERIFY(n == __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(short));
+ SatS::deallocate(sats, p, n);
+ }
+ {
+ auto [p, n] = SatS::allocate_at_least(sats, 2);
+ VERIFY(n == __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(short));
+ SatS::deallocate(sats, p, n);
+ }
+ {
+ auto [p, n] = SatS::allocate_at_least(sats,
+ (__STDCPP_DEFAULT_NEW_ALIGNMENT__ - 1) / sizeof(short));
+ VERIFY(n == __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(short));
+ SatS::deallocate(sats, p, n);
+ }
+ {
+ auto [p, n] = SatS::allocate_at_least(sats,
+ __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(short));
+ VERIFY(n == __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(short));
+ SatS::deallocate(sats, p, n);
+ }
+
+ struct A3 { char s[3]; };
+ using SatA3 = std::allocator_traits<std::allocator<A3>>;
+ std::allocator<A3> sata3;
+ {
+ auto [p, n] = SatA3::allocate_at_least(sata3, 1);
+ VERIFY(n == __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(A3));
+ SatA3::deallocate(sata3, p, n);
+ }
+ {
+ auto [p, n] = SatA3::allocate_at_least(sata3, 2);
+ VERIFY(n == __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(A3));
+ SatA3::deallocate(sata3, p, n);
+ }
+ {
+ auto [p, n] = SatA3::allocate_at_least(sata3,
+ (__STDCPP_DEFAULT_NEW_ALIGNMENT__ - 1) / sizeof(A3));
+ VERIFY(n == __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(A3));
+ SatA3::deallocate(sata3, p, n);
+ }
+ {
+ auto [p, n] = SatA3::allocate_at_least(sata3,
+ __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(A3));
+ VERIFY(n == __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(A3));
+ SatA3::deallocate(sata3, p, n);
+ }
+
+ struct Anm1 { char s[__STDCPP_DEFAULT_NEW_ALIGNMENT__ - 1]; };
+ using SatAnm1 = std::allocator_traits<std::allocator<Anm1>>;
+ std::allocator<Anm1> satanm1;
+ {
+ auto [p, n] = SatAnm1::allocate_at_least(satanm1, 1);
+ VERIFY(n == 1);
+ SatAnm1::deallocate(satanm1, p, n);
+ }
+ {
+ auto [p, n] = SatAnm1::allocate_at_least(satanm1,
+ __STDCPP_DEFAULT_NEW_ALIGNMENT__);
+ VERIFY(n == __STDCPP_DEFAULT_NEW_ALIGNMENT__);
+ SatAnm1::deallocate(satanm1, p, n);
+ }
+ {
+ auto [p, n] = SatAnm1::allocate_at_least(satanm1,
+ __STDCPP_DEFAULT_NEW_ALIGNMENT__ - 1);
+ VERIFY(n == __STDCPP_DEFAULT_NEW_ALIGNMENT__);
+ SatAnm1::deallocate(satanm1, p, n);
+ }
+}
+
+int main()
+{
+ base();
+ extra();
+}
diff --git a/libstdc++-v3/testsuite/21_strings/basic_string/capacity/char/18654.cc b/libstdc++-v3/testsuite/21_strings/basic_string/capacity/char/18654.cc
index d542f34d08e..59012a1c170 100644
--- a/libstdc++-v3/testsuite/21_strings/basic_string/capacity/char/18654.cc
+++ b/libstdc++-v3/testsuite/21_strings/basic_string/capacity/char/18654.cc
@@ -58,7 +58,12 @@ void test01()
#else
str.shrink_to_fit(); // reserve is deprecated in C++20
#endif
- VERIFY( str.capacity() == i );
+#if __glibcxx_allocate_at_least
+ unsigned limit = __STDCPP_DEFAULT_NEW_ALIGNMENT__ - 1;
+#else
+ unsigned limit = 0;
+#endif
+ VERIFY( str.capacity() - i <= limit);
}
}
diff --git a/libstdc++-v3/testsuite/21_strings/basic_string/capacity/char/shrink_to_fit.cc b/libstdc++-v3/testsuite/21_strings/basic_string/capacity/char/shrink_to_fit.cc
index a26d524dddf..ae5df746f35 100644
--- a/libstdc++-v3/testsuite/21_strings/basic_string/capacity/char/shrink_to_fit.cc
+++ b/libstdc++-v3/testsuite/21_strings/basic_string/capacity/char/shrink_to_fit.cc
@@ -30,7 +30,12 @@ void test01()
s.push_back('b');
VERIFY( s.size() < s.capacity() );
s.shrink_to_fit();
- VERIFY( s.size() == s.capacity() );
+#ifdef __glibcxx_allocate_at_least
+ unsigned limit = __STDCPP_DEFAULT_NEW_ALIGNMENT__ - 1;
+#else
+ unsigned limit = 0;
+#endif
+ VERIFY( s.capacity() - s.size() <= limit );
}
int main()
diff --git a/libstdc++-v3/testsuite/21_strings/basic_string/capacity/wchar_t/18654.cc b/libstdc++-v3/testsuite/21_strings/basic_string/capacity/wchar_t/18654.cc
index 49e45c764c4..bf3b8dd5581 100644
--- a/libstdc++-v3/testsuite/21_strings/basic_string/capacity/wchar_t/18654.cc
+++ b/libstdc++-v3/testsuite/21_strings/basic_string/capacity/wchar_t/18654.cc
@@ -50,6 +50,7 @@ void test01()
const size_type cap = str.capacity();
VERIFY( cap >= 3 * i );
+ // no shrink.
str.reserve(2 * i);
VERIFY( str.capacity() == cap );
@@ -58,7 +59,12 @@ void test01()
#else
str.shrink_to_fit(); // reserve is deprecated in C++20
#endif
- VERIFY( str.capacity() == i );
+#if __glibcxx_allocate_at_least
+ unsigned limit = __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(wchar_t) - 1;
+#else
+ unsigned limit = 0;
+#endif
+ VERIFY( str.capacity() - i <= limit);
}
}
diff --git a/libstdc++-v3/testsuite/21_strings/basic_string/capacity/wchar_t/2.cc b/libstdc++-v3/testsuite/21_strings/basic_string/capacity/wchar_t/2.cc
index bff2bdd1862..04a3763fc77 100644
--- a/libstdc++-v3/testsuite/21_strings/basic_string/capacity/wchar_t/2.cc
+++ b/libstdc++-v3/testsuite/21_strings/basic_string/capacity/wchar_t/2.cc
@@ -27,14 +27,21 @@
void test02()
{
std::wstring str01 = L"twelve chars";
- // str01 becomes shared
- std::wstring str02 = str01;
+ str01.reserve(100);
#if __cplusplus <= 201703L
str01.reserve();
#else
str01.shrink_to_fit(); // reserve is deprecated in C++20
#endif
- VERIFY( str01.capacity() == 12 );
+ // These are not guaranteed to absolutely minimize storage.
+ // allocator<wchar_t>::allocate_at_least rounds up to what
+ // it knows ::op new delivers.
+#ifdef __glibcxx_allocate_at_least
+ unsigned limit = __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(wchar_t) - 1;
+#else
+ unsigned limit = 0;
+#endif
+ VERIFY( str01.capacity() - str01.size() <= limit);
}
int main()
diff --git a/libstdc++-v3/testsuite/21_strings/basic_string/capacity/wchar_t/shrink_to_fit.cc b/libstdc++-v3/testsuite/21_strings/basic_string/capacity/wchar_t/shrink_to_fit.cc
index b4d0224a9d8..fc0f659539f 100644
--- a/libstdc++-v3/testsuite/21_strings/basic_string/capacity/wchar_t/shrink_to_fit.cc
+++ b/libstdc++-v3/testsuite/21_strings/basic_string/capacity/wchar_t/shrink_to_fit.cc
@@ -30,7 +30,12 @@ void test01()
s.push_back(L'b');
VERIFY( s.size() < s.capacity() );
s.shrink_to_fit();
- VERIFY( s.size() == s.capacity() );
+#ifdef __glibcxx_allocate_at_least
+ unsigned limit = __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(wchar_t) - 1;
+#else
+ unsigned limit = 0;
+#endif
+ VERIFY( s.capacity() - s.size() <= limit );
}
int main()
diff --git a/libstdc++-v3/testsuite/23_containers/vector/capacity/shrink_to_fit.cc b/libstdc++-v3/testsuite/23_containers/vector/capacity/shrink_to_fit.cc
index 74c68712b47..d4aa4d89b56 100644
--- a/libstdc++-v3/testsuite/23_containers/vector/capacity/shrink_to_fit.cc
+++ b/libstdc++-v3/testsuite/23_containers/vector/capacity/shrink_to_fit.cc
@@ -30,11 +30,12 @@ void test01()
v.push_back(1);
VERIFY( v.size() < v.capacity() );
v.shrink_to_fit();
-#if __cpp_exceptions
- VERIFY( v.size() == v.capacity() );
+#ifdef __glibcxx_allocate_at_least
+ unsigned limit = __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(int);
#else
- VERIFY( v.size() < v.capacity() );
+ unsigned limit = 0;
#endif
+ VERIFY(v.capacity() - v.size() <= limit);
}
int main()
diff --git a/libstdc++-v3/testsuite/23_containers/vector/capacity/shrink_to_fit2.cc b/libstdc++-v3/testsuite/23_containers/vector/capacity/shrink_to_fit2.cc
index c8faa9ded80..9489e043845 100644
--- a/libstdc++-v3/testsuite/23_containers/vector/capacity/shrink_to_fit2.cc
+++ b/libstdc++-v3/testsuite/23_containers/vector/capacity/shrink_to_fit2.cc
@@ -32,7 +32,12 @@ void test01()
v.reserve(100);
VERIFY( v.size() < v.capacity() );
v.shrink_to_fit();
- VERIFY( v.size() == v.capacity() );
+#ifdef __glibcxx_allocate_at_least
+ unsigned limit = __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(int);
+#else
+ unsigned limit = 0;
+#endif
+ VERIFY( v.capacity() - v.size() <= limit);
VERIFY( v.get_allocator().get_personality() == alloc.get_personality() );
}
@@ -45,7 +50,12 @@ void test02()
v.reserve(100);
VERIFY( v.size() < v.capacity() );
v.shrink_to_fit();
- VERIFY( v.size() == v.capacity() );
+#ifdef __glibcxx_allocate_at_least
+ unsigned limit = __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(int);
+#else
+ unsigned limit = 0;
+#endif
+ VERIFY( v.capacity() - v.size() <= limit);
VERIFY( v.get_allocator().get_personality() == alloc.get_personality() );
}
diff --git a/libstdc++-v3/testsuite/23_containers/vector/modifiers/emplace/self_emplace.cc b/libstdc++-v3/testsuite/23_containers/vector/modifiers/emplace/self_emplace.cc
index 00a0c7b06ea..629f35f05ba 100644
--- a/libstdc++-v3/testsuite/23_containers/vector/modifiers/emplace/self_emplace.cc
+++ b/libstdc++-v3/testsuite/23_containers/vector/modifiers/emplace/self_emplace.cc
@@ -99,37 +99,37 @@ struct A
void
test03()
{
- std::vector<A> va =
- {
- { A(1) },
- { A(2) },
- { A(3) }
- };
-
- // Make sure emplace will imply reallocation.
- VERIFY( va.capacity() == 3 );
+#ifdef __glibcxx_allocate_at_least
+ unsigned fit = __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(A);
+#else
+ unsigned fit = 4;
+#endif
+ std::vector<A> va; va.reserve(fit);
+ for (int i = 1; va.size() < va.capacity(); ++i)
+ va.push_back(A(i));
va.emplace(va.begin(), va.begin());
- VERIFY( va.size() == 4 );
+ VERIFY( va.size() == fit + 1 );
VERIFY( va[0]._i == 1 );
}
void
test04()
{
- std::vector<A> va =
- {
- { A(1) },
- { A(2) },
- { A(3) }
- };
+#ifdef __glibcxx_allocate_at_least
+ unsigned fit = __STDCPP_DEFAULT_NEW_ALIGNMENT__ / sizeof(A);
+#else
+ unsigned fit = 4;
+#endif
+ std::vector<A> va; va.reserve(fit);
+ for (int i = 1; va.size() < va.capacity() - 1; ++i)
+ va.push_back(A(i));
// Make sure emplace won't reallocate.
- va.reserve(4);
va.emplace(va.begin(), va.begin());
- VERIFY( va.size() == 4 );
+ VERIFY( va.size() == fit );
VERIFY( va[0]._i == 1 );
}
diff --git a/libstdc++-v3/testsuite/util/testsuite_allocator.h b/libstdc++-v3/testsuite/util/testsuite_allocator.h
index 892a385e307..1b3e1e8bb16 100644
--- a/libstdc++-v3/testsuite/util/testsuite_allocator.h
+++ b/libstdc++-v3/testsuite/util/testsuite_allocator.h
@@ -168,6 +168,16 @@ namespace __gnu_test
: Alloc(alloc)
{ }
+#ifdef __glibcxx_allocate_at_least // C++23
+ std::allocation_result<pointer, size_type>
+ allocate_at_least(size_type n)
+ {
+ auto [p, c] = AllocTraits::allocate_at_least(*this, n);
+ counter_type::allocate(c * sizeof(T));
+ return { p, c };
+ }
+#endif
+
pointer
allocate(size_type n, const void* = 0)
{
@@ -373,6 +383,32 @@ namespace __gnu_test
return p;
}
+#ifdef __glibcxx_allocate_at_least
+ constexpr auto
+ allocate_at_least(size_type n)
+ -> std::allocation_result<Tp*, size_t>
+ {
+ auto r = AllocTraits::allocate_at_least(*this, n);
+
+ if consteval
+ { return r; }
+ else
+ {
+ try
+ {
+ get_map().insert(map_type::value_type(
+ reinterpret_cast<void*>(r.ptr), personality));
+ }
+ catch(...)
+ {
+ AllocTraits::deallocate(*this, r.ptr, r.count);
+ __throw_exception_again;
+ }
+ return r;
+ }
+ }
+#endif
+
_GLIBCXX14_CONSTEXPR
void
deallocate(pointer p, size_type n)
--
2.53.0
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