1// Vector implementation -*- C++ -*-
2
3// Copyright (C) 2001-2026 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/*
26 *
27 * Copyright (c) 1994
28 * Hewlett-Packard Company
29 *
30 * Permission to use, copy, modify, distribute and sell this software
31 * and its documentation for any purpose is hereby granted without fee,
32 * provided that the above copyright notice appear in all copies and
33 * that both that copyright notice and this permission notice appear
34 * in supporting documentation. Hewlett-Packard Company makes no
35 * representations about the suitability of this software for any
36 * purpose. It is provided "as is" without express or implied warranty.
37 *
38 *
39 * Copyright (c) 1996
40 * Silicon Graphics Computer Systems, Inc.
41 *
42 * Permission to use, copy, modify, distribute and sell this software
43 * and its documentation for any purpose is hereby granted without fee,
44 * provided that the above copyright notice appear in all copies and
45 * that both that copyright notice and this permission notice appear
46 * in supporting documentation. Silicon Graphics makes no
47 * representations about the suitability of this software for any
48 * purpose. It is provided "as is" without express or implied warranty.
49 */
50
51/** @file bits/stl_vector.h
52 * This is an internal header file, included by other library headers.
53 * Do not attempt to use it directly. @headername{vector}
54 */
55
56#ifndef _STL_VECTOR_H
57#define _STL_VECTOR_H 1
58
59#include <bits/stl_iterator_base_funcs.h>
60#include <bits/stdexcept_throw.h>
61#include <bits/concept_check.h>
62#if __cplusplus >= 201103L
63#include <initializer_list>
64#endif
65#if __cplusplus >= 202002L
66# include <compare>
67#endif
68#if __glibcxx_concepts // C++ >= C++20
69# include <bits/ranges_base.h> // ranges::distance
70#endif
71#if __glibcxx_containers_ranges // C++ >= 23
72# include <bits/ranges_algobase.h> // ranges::copy
73# include <bits/ranges_util.h> // ranges::subrange
74#endif
75
76#include <debug/assertions.h>
77
78#if _GLIBCXX_SANITIZE_STD_ALLOCATOR && _GLIBCXX_SANITIZE_VECTOR
79extern "C" void
80__sanitizer_annotate_contiguous_container(const void*, const void*,
81 const void*, const void*);
82#endif
83
84namespace std _GLIBCXX_VISIBILITY(default)
85{
86_GLIBCXX_BEGIN_NAMESPACE_VERSION
87_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
88
89 /// See bits/stl_deque.h's _Deque_base for an explanation.
90 template<typename _Tp, typename _Alloc>
91 struct _Vector_base
92 {
93 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
94 rebind<_Tp>::other _Tp_alloc_type;
95 typedef typename __gnu_cxx::__alloc_traits<_Tp_alloc_type>::pointer
96 pointer;
97
98 struct _Vector_impl_data
99 {
100 pointer _M_start;
101 pointer _M_finish;
102 pointer _M_end_of_storage;
103
104 _GLIBCXX20_CONSTEXPR
105 _Vector_impl_data() _GLIBCXX_NOEXCEPT
106 : _M_start(), _M_finish(), _M_end_of_storage()
107 { }
108
109#if __cplusplus >= 201103L
110 _GLIBCXX20_CONSTEXPR
111 _Vector_impl_data(_Vector_impl_data&& __x) noexcept
112 : _M_start(__x._M_start), _M_finish(__x._M_finish),
113 _M_end_of_storage(__x._M_end_of_storage)
114 { __x._M_start = __x._M_finish = __x._M_end_of_storage = pointer(); }
115#endif
116
117 _GLIBCXX20_CONSTEXPR
118 void
119 _M_copy_data(_Vector_impl_data const& __x) _GLIBCXX_NOEXCEPT
120 {
121 _M_start = __x._M_start;
122 _M_finish = __x._M_finish;
123 _M_end_of_storage = __x._M_end_of_storage;
124 }
125
126 _GLIBCXX20_CONSTEXPR
127 void
128 _M_swap_data(_Vector_impl_data& __x) _GLIBCXX_NOEXCEPT
129 {
130 // Do not use std::swap(_M_start, __x._M_start), etc as it loses
131 // information used by TBAA.
132 _Vector_impl_data __tmp;
133 __tmp._M_copy_data(x: *this);
134 _M_copy_data(__x);
135 __x._M_copy_data(x: __tmp);
136 }
137 };
138
139 struct _Vector_impl
140 : public _Tp_alloc_type, public _Vector_impl_data
141 {
142 _GLIBCXX20_CONSTEXPR
143 _Vector_impl() _GLIBCXX_NOEXCEPT_IF(
144 is_nothrow_default_constructible<_Tp_alloc_type>::value)
145#if __cpp_lib_concepts
146 requires is_default_constructible_v<_Tp_alloc_type>
147#endif
148 : _Tp_alloc_type()
149 { }
150
151 _GLIBCXX20_CONSTEXPR
152 _Vector_impl(_Tp_alloc_type const& __a) _GLIBCXX_NOEXCEPT
153 : _Tp_alloc_type(__a)
154 { }
155
156#if __cplusplus >= 201103L
157 // Not defaulted, to enforce noexcept(true) even when
158 // !is_nothrow_move_constructible<_Tp_alloc_type>.
159 _GLIBCXX20_CONSTEXPR
160 _Vector_impl(_Vector_impl&& __x) noexcept
161 : _Tp_alloc_type(std::move(__x)), _Vector_impl_data(std::move(__x))
162 { }
163
164 _GLIBCXX20_CONSTEXPR
165 _Vector_impl(_Tp_alloc_type&& __a) noexcept
166 : _Tp_alloc_type(std::move(__a))
167 { }
168
169 _GLIBCXX20_CONSTEXPR
170 _Vector_impl(_Tp_alloc_type&& __a, _Vector_impl&& __rv) noexcept
171 : _Tp_alloc_type(std::move(__a)), _Vector_impl_data(std::move(__rv))
172 { }
173#endif
174
175#if _GLIBCXX_SANITIZE_STD_ALLOCATOR && _GLIBCXX_SANITIZE_VECTOR
176 template<typename = _Tp_alloc_type>
177 struct _Asan
178 {
179 typedef typename __gnu_cxx::__alloc_traits<_Tp_alloc_type>
180 ::size_type size_type;
181
182 static _GLIBCXX20_CONSTEXPR void
183 _S_shrink(_Vector_impl&, size_type) { }
184 static _GLIBCXX20_CONSTEXPR void
185 _S_on_dealloc(_Vector_impl&) { }
186
187 typedef _Vector_impl& _Reinit;
188
189 struct _Grow
190 {
191 _GLIBCXX20_CONSTEXPR _Grow(_Vector_impl&, size_type) { }
192 _GLIBCXX20_CONSTEXPR void _M_grew(size_type) { }
193 };
194 };
195
196 // Enable ASan annotations for memory obtained from std::allocator.
197 template<typename _Up>
198 struct _Asan<allocator<_Up> >
199 {
200 typedef typename __gnu_cxx::__alloc_traits<_Tp_alloc_type>
201 ::size_type size_type;
202
203 // Adjust ASan annotation for [_M_start, _M_end_of_storage) to
204 // mark end of valid region as __curr instead of __prev.
205 static _GLIBCXX20_CONSTEXPR void
206 _S_adjust(_Vector_impl& __impl, pointer __prev, pointer __curr)
207 {
208#if __cpp_lib_is_constant_evaluated
209 if (std::is_constant_evaluated())
210 return;
211#endif
212 __sanitizer_annotate_contiguous_container(__impl._M_start,
213 __impl._M_end_of_storage, __prev, __curr);
214 }
215
216 static _GLIBCXX20_CONSTEXPR void
217 _S_grow(_Vector_impl& __impl, size_type __n)
218 { _S_adjust(__impl, __impl._M_finish, __impl._M_finish + __n); }
219
220 static _GLIBCXX20_CONSTEXPR void
221 _S_shrink(_Vector_impl& __impl, size_type __n)
222 { _S_adjust(__impl, __impl._M_finish + __n, __impl._M_finish); }
223
224 static _GLIBCXX20_CONSTEXPR void
225 _S_on_dealloc(_Vector_impl& __impl)
226 {
227 if (__impl._M_start)
228 _S_adjust(__impl, __impl._M_finish, __impl._M_end_of_storage);
229 }
230
231 // Used on reallocation to tell ASan unused capacity is invalid.
232 struct _Reinit
233 {
234 explicit _GLIBCXX20_CONSTEXPR
235 _Reinit(_Vector_impl& __impl) : _M_impl(__impl)
236 {
237 // Mark unused capacity as valid again before deallocating it.
238 _S_on_dealloc(_M_impl);
239 }
240
241 _GLIBCXX20_CONSTEXPR
242 ~_Reinit()
243 {
244 // Mark unused capacity as invalid after reallocation.
245 if (_M_impl._M_start)
246 _S_adjust(_M_impl, _M_impl._M_end_of_storage,
247 _M_impl._M_finish);
248 }
249
250 _Vector_impl& _M_impl;
251
252#if __cplusplus >= 201103L
253 _Reinit(const _Reinit&) = delete;
254 _Reinit& operator=(const _Reinit&) = delete;
255#endif
256 };
257
258 // Tell ASan when unused capacity is initialized to be valid.
259 struct _Grow
260 {
261 _GLIBCXX20_CONSTEXPR
262 _Grow(_Vector_impl& __impl, size_type __n)
263 : _M_impl(__impl), _M_n(__n)
264 { _S_grow(_M_impl, __n); }
265
266 _GLIBCXX20_CONSTEXPR
267 ~_Grow() { if (_M_n) _S_shrink(_M_impl, _M_n); }
268
269 _GLIBCXX20_CONSTEXPR
270 void _M_grew(size_type __n) { _M_n -= __n; }
271
272#if __cplusplus >= 201103L
273 _Grow(const _Grow&) = delete;
274 _Grow& operator=(const _Grow&) = delete;
275#endif
276 private:
277 _Vector_impl& _M_impl;
278 size_type _M_n;
279 };
280 };
281
282#define _GLIBCXX_ASAN_ANNOTATE_REINIT \
283 typename _Base::_Vector_impl::template _Asan<>::_Reinit const \
284 __attribute__((__unused__)) __reinit_guard(this->_M_impl)
285#define _GLIBCXX_ASAN_ANNOTATE_GROW(n) \
286 typename _Base::_Vector_impl::template _Asan<>::_Grow \
287 __attribute__((__unused__)) __grow_guard(this->_M_impl, (n))
288#define _GLIBCXX_ASAN_ANNOTATE_GREW(n) __grow_guard._M_grew(n)
289#define _GLIBCXX_ASAN_ANNOTATE_SHRINK(n) \
290 _Base::_Vector_impl::template _Asan<>::_S_shrink(this->_M_impl, n)
291#define _GLIBCXX_ASAN_ANNOTATE_BEFORE_DEALLOC \
292 _Base::_Vector_impl::template _Asan<>::_S_on_dealloc(this->_M_impl)
293#else // ! (_GLIBCXX_SANITIZE_STD_ALLOCATOR && _GLIBCXX_SANITIZE_VECTOR)
294#define _GLIBCXX_ASAN_ANNOTATE_REINIT
295#define _GLIBCXX_ASAN_ANNOTATE_GROW(n)
296#define _GLIBCXX_ASAN_ANNOTATE_GREW(n)
297#define _GLIBCXX_ASAN_ANNOTATE_SHRINK(n)
298#define _GLIBCXX_ASAN_ANNOTATE_BEFORE_DEALLOC
299#endif // _GLIBCXX_SANITIZE_STD_ALLOCATOR && _GLIBCXX_SANITIZE_VECTOR
300 };
301
302 public:
303 typedef _Alloc allocator_type;
304
305 _GLIBCXX20_CONSTEXPR
306 _Tp_alloc_type&
307 _M_get_Tp_allocator() _GLIBCXX_NOEXCEPT
308 { return this->_M_impl; }
309
310 _GLIBCXX20_CONSTEXPR
311 const _Tp_alloc_type&
312 _M_get_Tp_allocator() const _GLIBCXX_NOEXCEPT
313 { return this->_M_impl; }
314
315 _GLIBCXX20_CONSTEXPR
316 allocator_type
317 get_allocator() const _GLIBCXX_NOEXCEPT
318 { return allocator_type(_M_get_Tp_allocator()); }
319
320#if __cplusplus >= 201103L
321 _Vector_base() = default;
322#else
323 _Vector_base() { }
324#endif
325
326 _GLIBCXX20_CONSTEXPR
327 _Vector_base(const allocator_type& __a) _GLIBCXX_NOEXCEPT
328 : _M_impl(__a) { }
329
330 // Kept for ABI compatibility.
331#if !_GLIBCXX_INLINE_VERSION
332 _GLIBCXX20_CONSTEXPR
333 _Vector_base(size_t __n)
334 : _M_impl()
335 { _M_create_storage(__n); }
336#endif
337
338 _GLIBCXX20_CONSTEXPR
339 _Vector_base(size_t __n, const allocator_type& __a)
340 : _M_impl(__a)
341 { _M_create_storage(__n); }
342
343#if __cplusplus >= 201103L
344 _Vector_base(_Vector_base&&) = default;
345
346 // Kept for ABI compatibility.
347# if !_GLIBCXX_INLINE_VERSION
348 _GLIBCXX20_CONSTEXPR
349 _Vector_base(_Tp_alloc_type&& __a) noexcept
350 : _M_impl(std::move(__a)) { }
351
352 _GLIBCXX20_CONSTEXPR
353 _Vector_base(_Vector_base&& __x, const allocator_type& __a)
354 : _M_impl(__a)
355 {
356 if (__x.get_allocator() == __a)
357 this->_M_impl._M_swap_data(__x._M_impl);
358 else
359 {
360 size_t __n = __x._M_impl._M_finish - __x._M_impl._M_start;
361 _M_create_storage(__n);
362 }
363 }
364# endif
365
366 _GLIBCXX20_CONSTEXPR
367 _Vector_base(const allocator_type& __a, _Vector_base&& __x)
368 : _M_impl(_Tp_alloc_type(__a), std::move(__x._M_impl))
369 { }
370#endif
371
372 _GLIBCXX20_CONSTEXPR
373 ~_Vector_base() _GLIBCXX_NOEXCEPT
374 {
375 ptrdiff_t __n = _M_impl._M_end_of_storage - _M_impl._M_start;
376 if (__n < 0)
377 __builtin_unreachable();
378 _M_deallocate(p: _M_impl._M_start, n: size_t(__n));
379 }
380
381 public:
382 _Vector_impl _M_impl;
383
384 _GLIBCXX20_CONSTEXPR
385 pointer
386 _M_allocate(size_t __n)
387 {
388 typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Tr;
389 return __n != 0 ? _Tr::allocate(_M_impl, __n) : pointer();
390 }
391
392 _GLIBCXX20_CONSTEXPR
393 void
394 _M_deallocate(pointer __p, size_t __n)
395 {
396 typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Tr;
397 if (__p)
398 _Tr::deallocate(_M_impl, __p, __n);
399 }
400
401 protected:
402
403 _GLIBCXX20_CONSTEXPR
404 void
405 _M_create_storage(size_t __n)
406 {
407 this->_M_impl._M_start = this->_M_allocate(__n);
408 this->_M_impl._M_finish = this->_M_impl._M_start;
409 this->_M_impl._M_end_of_storage = this->_M_impl._M_start + __n;
410 }
411
412#if __glibcxx_containers_ranges // C++ >= 23
413 // Called by insert_range, and indirectly by assign_range, append_range.
414 // Initializes new elements in storage at __ptr and updates __ptr to
415 // point after the last new element.
416 // Provides strong exception safety guarantee.
417 // Requires [ptr, ptr+distance(rg)) is a valid range.
418 template<ranges::input_range _Rg>
419 constexpr void
420 _M_append_range_to(_Rg&& __rg, pointer& __ptr)
421 {
422 __ptr = std::__uninitialized_copy_a(ranges::begin(__rg),
423 ranges::end(__rg),
424 __ptr, _M_get_Tp_allocator());
425 }
426
427 // Called by assign_range, append_range, insert_range.
428 // Requires capacity() >= size()+distance(rg).
429 template<ranges::input_range _Rg>
430 constexpr void
431 _M_append_range(_Rg&& __rg)
432 { _M_append_range_to(std::forward<_Rg>(__rg), _M_impl._M_finish); }
433#endif
434 };
435
436 /**
437 * @brief A standard container which offers fixed time access to
438 * individual elements in any order.
439 *
440 * @ingroup sequences
441 * @headerfile vector
442 * @since C++98
443 *
444 * @tparam _Tp Type of element.
445 * @tparam _Alloc Allocator type, defaults to allocator<_Tp>.
446 *
447 * Meets the requirements of a <a href="tables.html#65">container</a>, a
448 * <a href="tables.html#66">reversible container</a>, and a
449 * <a href="tables.html#67">sequence</a>, including the
450 * <a href="tables.html#68">optional sequence requirements</a> with the
451 * %exception of @c push_front and @c pop_front.
452 *
453 * In some terminology a %vector can be described as a dynamic
454 * C-style array, it offers fast and efficient access to individual
455 * elements in any order and saves the user from worrying about
456 * memory and size allocation. Subscripting ( @c [] ) access is
457 * also provided as with C-style arrays.
458 */
459 template<typename _Tp, typename _Alloc = std::allocator<_Tp> >
460 class vector : protected _Vector_base<_Tp, _Alloc>
461 {
462#ifdef _GLIBCXX_CONCEPT_CHECKS
463 // Concept requirements.
464 typedef typename _Alloc::value_type _Alloc_value_type;
465# if __cplusplus < 201103L
466 __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
467# endif
468 __glibcxx_class_requires2(_Tp, _Alloc_value_type, _SameTypeConcept)
469#endif
470
471#if __cplusplus >= 201103L
472 static_assert(is_same<typename remove_cv<_Tp>::type, _Tp>::value,
473 "std::vector must have a non-const, non-volatile value_type");
474# if __cplusplus > 201703L || defined __STRICT_ANSI__
475 static_assert(is_same<typename _Alloc::value_type, _Tp>::value,
476 "std::vector must have the same value_type as its allocator");
477# endif
478#endif
479
480 typedef _Vector_base<_Tp, _Alloc> _Base;
481 typedef typename _Base::_Tp_alloc_type _Tp_alloc_type;
482 typedef __gnu_cxx::__alloc_traits<_Tp_alloc_type> _Alloc_traits;
483
484 public:
485 typedef _Tp value_type;
486 typedef typename _Base::pointer pointer;
487 typedef typename _Alloc_traits::const_pointer const_pointer;
488 typedef typename _Alloc_traits::reference reference;
489 typedef typename _Alloc_traits::const_reference const_reference;
490 typedef __gnu_cxx::__normal_iterator<pointer, vector> iterator;
491 typedef __gnu_cxx::__normal_iterator<const_pointer, vector>
492 const_iterator;
493 typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
494 typedef std::reverse_iterator<iterator> reverse_iterator;
495 typedef size_t size_type;
496 typedef ptrdiff_t difference_type;
497 typedef _Alloc allocator_type;
498
499 private:
500#if __cplusplus >= 201103L
501 static constexpr bool
502 _S_nothrow_relocate(true_type)
503 {
504 return noexcept(std::__relocate_a(std::declval<pointer>(),
505 std::declval<pointer>(),
506 std::declval<pointer>(),
507 std::declval<_Tp_alloc_type&>()));
508 }
509
510 static constexpr bool
511 _S_nothrow_relocate(false_type)
512 { return false; }
513
514 static constexpr bool
515 _S_use_relocate()
516 {
517 // Instantiating std::__relocate_a might cause an error outside the
518 // immediate context (in __relocate_object_a's noexcept-specifier),
519 // so only do it if we know the type can be move-inserted into *this.
520 return _S_nothrow_relocate(__is_move_insertable<_Tp_alloc_type>{});
521 }
522
523 static _GLIBCXX20_CONSTEXPR pointer
524 _S_relocate(pointer __first, pointer __last, pointer __result,
525 _Tp_alloc_type& __alloc) noexcept
526 {
527#pragma GCC diagnostic push
528#pragma GCC diagnostic ignored "-Wc++17-extensions" // if constexpr
529 if constexpr (_S_use_relocate())
530 return std::__relocate_a(__first, __last, __result, __alloc);
531 else
532 return __result;
533#pragma GCC diagnostic pop
534 }
535#endif // C++11
536
537 protected:
538 using _Base::_M_allocate;
539 using _Base::_M_deallocate;
540 using _Base::_M_impl;
541 using _Base::_M_get_Tp_allocator;
542
543 public:
544 // [23.2.4.1] construct/copy/destroy
545 // (assign() and get_allocator() are also listed in this section)
546
547 /**
548 * @brief Creates a %vector with no elements.
549 */
550#if __cplusplus >= 201103L
551 vector() = default;
552#else
553 vector() { }
554#endif
555
556 /**
557 * @brief Creates a %vector with no elements.
558 * @param __a An allocator object.
559 */
560 explicit
561 _GLIBCXX20_CONSTEXPR
562 vector(const allocator_type& __a) _GLIBCXX_NOEXCEPT
563 : _Base(__a) { }
564
565#if __cplusplus >= 201103L
566 /**
567 * @brief Creates a %vector with default constructed elements.
568 * @param __n The number of elements to initially create.
569 * @param __a An allocator.
570 *
571 * This constructor fills the %vector with @a __n default
572 * constructed elements.
573 */
574 explicit
575 _GLIBCXX20_CONSTEXPR
576 vector(size_type __n, const allocator_type& __a = allocator_type())
577 : _Base(_S_check_init_len(__n, __a), __a)
578 { _M_default_initialize(__n); }
579
580 /**
581 * @brief Creates a %vector with copies of an exemplar element.
582 * @param __n The number of elements to initially create.
583 * @param __value An element to copy.
584 * @param __a An allocator.
585 *
586 * This constructor fills the %vector with @a __n copies of @a __value.
587 */
588 _GLIBCXX20_CONSTEXPR
589 vector(size_type __n, const value_type& __value,
590 const allocator_type& __a = allocator_type())
591 : _Base(_S_check_init_len(__n, __a), __a)
592 { _M_fill_initialize(__n, __value); }
593#else
594 /**
595 * @brief Creates a %vector with copies of an exemplar element.
596 * @param __n The number of elements to initially create.
597 * @param __value An element to copy.
598 * @param __a An allocator.
599 *
600 * This constructor fills the %vector with @a __n copies of @a __value.
601 */
602 explicit
603 vector(size_type __n, const value_type& __value = value_type(),
604 const allocator_type& __a = allocator_type())
605 : _Base(_S_check_init_len(__n, __a), __a)
606 { _M_fill_initialize(__n, __value); }
607#endif
608
609 /**
610 * @brief %Vector copy constructor.
611 * @param __x A %vector of identical element and allocator types.
612 *
613 * All the elements of @a __x are copied, but any unused capacity in
614 * @a __x will not be copied
615 * (i.e. capacity() == size() in the new %vector).
616 *
617 * The newly-created %vector uses a copy of the allocator object used
618 * by @a __x (unless the allocator traits dictate a different object).
619 */
620 _GLIBCXX20_CONSTEXPR
621 vector(const vector& __x)
622 : _Base(__x.size(),
623 _Alloc_traits::_S_select_on_copy(__x._M_get_Tp_allocator()))
624 {
625 this->_M_impl._M_finish =
626 std::__uninitialized_copy_a(__x.begin(), __x.end(),
627 this->_M_impl._M_start,
628 _M_get_Tp_allocator());
629 }
630
631#if __cplusplus >= 201103L
632 /**
633 * @brief %Vector move constructor.
634 *
635 * The newly-created %vector contains the exact contents of the
636 * moved instance.
637 * The contents of the moved instance are a valid, but unspecified
638 * %vector.
639 */
640 vector(vector&&) noexcept = default;
641
642 /// Copy constructor with alternative allocator
643 _GLIBCXX20_CONSTEXPR
644 vector(const vector& __x, const __type_identity_t<allocator_type>& __a)
645 : _Base(__x.size(), __a)
646 {
647 this->_M_impl._M_finish =
648 std::__uninitialized_copy_a(__x.begin(), __x.end(),
649 this->_M_impl._M_start,
650 _M_get_Tp_allocator());
651 }
652
653 private:
654 _GLIBCXX20_CONSTEXPR
655 vector(vector&& __rv, const allocator_type& __m, true_type) noexcept
656 : _Base(__m, std::move(__rv))
657 { }
658
659 _GLIBCXX20_CONSTEXPR
660 vector(vector&& __rv, const allocator_type& __m, false_type)
661 : _Base(__m)
662 {
663 if (__rv.get_allocator() == __m)
664 this->_M_impl._M_swap_data(__rv._M_impl);
665 else if (!__rv.empty())
666 {
667 this->_M_create_storage(__rv.size());
668 this->_M_impl._M_finish =
669 std::__uninitialized_move_a(__rv.begin(), __rv.end(),
670 this->_M_impl._M_start,
671 _M_get_Tp_allocator());
672 __rv.clear();
673 }
674 }
675
676 public:
677 /// Move constructor with alternative allocator
678 _GLIBCXX20_CONSTEXPR
679 vector(vector&& __rv, const __type_identity_t<allocator_type>& __m)
680 noexcept( noexcept(
681 vector(std::declval<vector&&>(), std::declval<const allocator_type&>(),
682 std::declval<typename _Alloc_traits::is_always_equal>())) )
683 : vector(std::move(__rv), __m, typename _Alloc_traits::is_always_equal{})
684 { }
685
686 /**
687 * @brief Builds a %vector from an initializer list.
688 * @param __l An initializer_list.
689 * @param __a An allocator.
690 *
691 * Create a %vector consisting of copies of the elements in the
692 * initializer_list @a __l.
693 *
694 * This will call the element type's copy constructor N times
695 * (where N is @a __l.size()) and do no memory reallocation.
696 */
697 _GLIBCXX20_CONSTEXPR
698 vector(initializer_list<value_type> __l,
699 const allocator_type& __a = allocator_type())
700 : _Base(__a)
701 {
702 _M_range_initialize_n(__l.begin(), __l.end(), __l.size());
703 }
704#endif
705
706 /**
707 * @brief Builds a %vector from a range.
708 * @param __first An input iterator.
709 * @param __last An input iterator.
710 * @param __a An allocator.
711 *
712 * Create a %vector consisting of copies of the elements from
713 * [first,last).
714 *
715 * If the iterators are forward, bidirectional, or
716 * random-access, then this will call the elements' copy
717 * constructor N times (where N is distance(first,last)) and do
718 * no memory reallocation. But if only input iterators are
719 * used, then this will do at most 2N calls to the copy
720 * constructor, and logN memory reallocations.
721 */
722#if __cplusplus >= 201103L
723 template<typename _InputIterator,
724 typename = std::_RequireInputIter<_InputIterator>>
725 _GLIBCXX20_CONSTEXPR
726 vector(_InputIterator __first, _InputIterator __last,
727 const allocator_type& __a = allocator_type())
728 : _Base(__a)
729 {
730#if __glibcxx_concepts // C++ >= C++20
731 if constexpr (sized_sentinel_for<_InputIterator, _InputIterator>
732 || forward_iterator<_InputIterator>)
733 {
734 const auto __n
735 = static_cast<size_type>(ranges::distance(__first, __last));
736 _M_range_initialize_n(__first, __last, __n);
737 return;
738 }
739 else
740#endif
741 _M_range_initialize(__first, __last,
742 std::__iterator_category(__first));
743 }
744#else
745 template<typename _InputIterator>
746 vector(_InputIterator __first, _InputIterator __last,
747 const allocator_type& __a = allocator_type())
748 : _Base(__a)
749 {
750 // Check whether it's an integral type. If so, it's not an iterator.
751 typedef typename std::__is_integer<_InputIterator>::__type _Integral;
752 _M_initialize_dispatch(__first, __last, _Integral());
753 }
754#endif
755
756#if __glibcxx_containers_ranges // C++ >= 23
757 /**
758 * @brief Construct a vector from a range.
759 * @param __rg A range of values that are convertible to `bool`.
760 * @since C++23
761 */
762 template<__detail::__container_compatible_range<_Tp> _Rg>
763 constexpr
764 vector(from_range_t, _Rg&& __rg, const _Alloc& __a = _Alloc())
765 : vector(__a)
766 {
767 if constexpr (ranges::forward_range<_Rg> || ranges::sized_range<_Rg>)
768 {
769 const auto __n = static_cast<size_type>(ranges::distance(__rg));
770 _M_range_initialize_n(ranges::begin(__rg), ranges::end(__rg),
771 __n);
772 }
773 else
774 {
775 auto __first = ranges::begin(__rg);
776 const auto __last = ranges::end(__rg);
777 for (; __first != __last; ++__first)
778 emplace_back(*__first);
779 }
780 }
781#endif
782
783 /**
784 * The dtor only erases the elements, and note that if the
785 * elements themselves are pointers, the pointed-to memory is
786 * not touched in any way. Managing the pointer is the user's
787 * responsibility.
788 */
789 _GLIBCXX20_CONSTEXPR
790 ~vector() _GLIBCXX_NOEXCEPT
791 {
792 std::_Destroy(this->_M_impl._M_start, this->_M_impl._M_finish,
793 _M_get_Tp_allocator());
794 _GLIBCXX_ASAN_ANNOTATE_BEFORE_DEALLOC;
795 }
796
797 /**
798 * @brief %Vector assignment operator.
799 * @param __x A %vector of identical element and allocator types.
800 *
801 * All the elements of @a __x are copied, but any unused capacity in
802 * @a __x will not be copied.
803 *
804 * Whether the allocator is copied depends on the allocator traits.
805 */
806 _GLIBCXX20_CONSTEXPR
807 vector&
808 operator=(const vector& __x);
809
810#if __cplusplus >= 201103L
811 /**
812 * @brief %Vector move assignment operator.
813 * @param __x A %vector of identical element and allocator types.
814 *
815 * The contents of @a __x are moved into this %vector (without copying,
816 * if the allocators permit it).
817 * Afterwards @a __x is a valid, but unspecified %vector.
818 *
819 * Whether the allocator is moved depends on the allocator traits.
820 */
821 _GLIBCXX20_CONSTEXPR
822 vector&
823 operator=(vector&& __x) noexcept(_Alloc_traits::_S_nothrow_move())
824 {
825 constexpr bool __move_storage =
826 _Alloc_traits::_S_propagate_on_move_assign()
827 || _Alloc_traits::_S_always_equal();
828 _M_move_assign(std::move(__x), __bool_constant<__move_storage>());
829 return *this;
830 }
831
832 /**
833 * @brief %Vector list assignment operator.
834 * @param __l An initializer_list.
835 *
836 * This function fills a %vector with copies of the elements in the
837 * initializer list @a __l.
838 *
839 * Note that the assignment completely changes the %vector and
840 * that the resulting %vector's size is the same as the number
841 * of elements assigned.
842 */
843 _GLIBCXX20_CONSTEXPR
844 vector&
845 operator=(initializer_list<value_type> __l)
846 {
847 this->_M_assign_aux(__l.begin(), __l.end(),
848 random_access_iterator_tag());
849 return *this;
850 }
851#endif
852
853 /**
854 * @brief Assigns a given value to a %vector.
855 * @param __n Number of elements to be assigned.
856 * @param __val Value to be assigned.
857 *
858 * This function fills a %vector with @a __n copies of the given
859 * value. Note that the assignment completely changes the
860 * %vector and that the resulting %vector's size is the same as
861 * the number of elements assigned.
862 */
863 _GLIBCXX20_CONSTEXPR
864 void
865 assign(size_type __n, const value_type& __val)
866 { _M_fill_assign(__n, __val); }
867
868 /**
869 * @brief Assigns a range to a %vector.
870 * @param __first An input iterator.
871 * @param __last An input iterator.
872 *
873 * This function fills a %vector with copies of the elements in the
874 * range [__first,__last).
875 *
876 * Note that the assignment completely changes the %vector and
877 * that the resulting %vector's size is the same as the number
878 * of elements assigned.
879 */
880#if __cplusplus >= 201103L
881 template<typename _InputIterator,
882 typename = std::_RequireInputIter<_InputIterator>>
883 _GLIBCXX20_CONSTEXPR
884 void
885 assign(_InputIterator __first, _InputIterator __last)
886 { _M_assign_aux(__first, __last, std::__iterator_category(__first)); }
887#else
888 template<typename _InputIterator>
889 void
890 assign(_InputIterator __first, _InputIterator __last)
891 {
892 // Check whether it's an integral type. If so, it's not an iterator.
893 typedef typename std::__is_integer<_InputIterator>::__type _Integral;
894 _M_assign_dispatch(__first, __last, _Integral());
895 }
896#endif
897
898#if __cplusplus >= 201103L
899 /**
900 * @brief Assigns an initializer list to a %vector.
901 * @param __l An initializer_list.
902 *
903 * This function fills a %vector with copies of the elements in the
904 * initializer list @a __l.
905 *
906 * Note that the assignment completely changes the %vector and
907 * that the resulting %vector's size is the same as the number
908 * of elements assigned.
909 */
910 _GLIBCXX20_CONSTEXPR
911 void
912 assign(initializer_list<value_type> __l)
913 {
914 this->_M_assign_aux(__l.begin(), __l.end(),
915 random_access_iterator_tag());
916 }
917#endif
918
919#if __glibcxx_containers_ranges // C++ >= 23
920 /**
921 * @brief Assign a range to the vector.
922 * @param __rg A range of values that are convertible to `value_type`.
923 * @pre `__rg` and `*this` do not overlap.
924 * @since C++23
925 */
926 template<__detail::__container_compatible_range<_Tp> _Rg>
927 constexpr void
928 assign_range(_Rg&& __rg)
929 {
930 static_assert(assignable_from<_Tp&, ranges::range_reference_t<_Rg>>);
931
932 if constexpr (ranges::forward_range<_Rg> || ranges::sized_range<_Rg>)
933 {
934 const auto __n = size_type(ranges::distance(__rg));
935 if (__n <= size())
936 {
937 auto __res = ranges::copy(__rg, this->_M_impl._M_start);
938 _M_erase_at_end(__res.out);
939 return;
940 }
941
942 reserve(__n);
943 auto __first = ranges::copy_n(ranges::begin(__rg), size(),
944 this->_M_impl._M_start).in;
945 [[maybe_unused]] const auto __diff = __n - size();
946 _GLIBCXX_ASAN_ANNOTATE_GROW(__diff);
947 _Base::_M_append_range(ranges::subrange(std::move(__first),
948 ranges::end(__rg)));
949 _GLIBCXX_ASAN_ANNOTATE_GREW(__diff);
950 }
951 else // input_range<_Rg> && !sized_range<_Rg>
952 {
953 auto __first = ranges::begin(__rg);
954 const auto __last = ranges::end(__rg);
955 pointer __ptr = this->_M_impl._M_start;
956 pointer const __end = this->_M_impl._M_finish;
957
958 while (__ptr < __end && __first != __last)
959 {
960 *__ptr = *__first;
961 ++__ptr;
962 ++__first;
963 }
964
965 if (__first == __last)
966 _M_erase_at_end(__ptr);
967 else
968 {
969 do
970 emplace_back(*__first);
971 while (++__first != __last);
972 }
973 }
974 }
975#endif // containers_ranges
976
977 /// Get a copy of the memory allocation object.
978 using _Base::get_allocator;
979
980 // iterators
981 /**
982 * Returns a read/write iterator that points to the first
983 * element in the %vector. Iteration is done in ordinary
984 * element order.
985 */
986 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
987 iterator
988 begin() _GLIBCXX_NOEXCEPT
989 { return iterator(this->_M_impl._M_start); }
990
991 /**
992 * Returns a read-only (constant) iterator that points to the
993 * first element in the %vector. Iteration is done in ordinary
994 * element order.
995 */
996 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
997 const_iterator
998 begin() const _GLIBCXX_NOEXCEPT
999 { return const_iterator(this->_M_impl._M_start); }
1000
1001 /**
1002 * Returns a read/write iterator that points one past the last
1003 * element in the %vector. Iteration is done in ordinary
1004 * element order.
1005 */
1006 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1007 iterator
1008 end() _GLIBCXX_NOEXCEPT
1009 { return iterator(this->_M_impl._M_finish); }
1010
1011 /**
1012 * Returns a read-only (constant) iterator that points one past
1013 * the last element in the %vector. Iteration is done in
1014 * ordinary element order.
1015 */
1016 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1017 const_iterator
1018 end() const _GLIBCXX_NOEXCEPT
1019 { return const_iterator(this->_M_impl._M_finish); }
1020
1021 /**
1022 * Returns a read/write reverse iterator that points to the
1023 * last element in the %vector. Iteration is done in reverse
1024 * element order.
1025 */
1026 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1027 reverse_iterator
1028 rbegin() _GLIBCXX_NOEXCEPT
1029 { return reverse_iterator(end()); }
1030
1031 /**
1032 * Returns a read-only (constant) reverse iterator that points
1033 * to the last element in the %vector. Iteration is done in
1034 * reverse element order.
1035 */
1036 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1037 const_reverse_iterator
1038 rbegin() const _GLIBCXX_NOEXCEPT
1039 { return const_reverse_iterator(end()); }
1040
1041 /**
1042 * Returns a read/write reverse iterator that points to one
1043 * before the first element in the %vector. Iteration is done
1044 * in reverse element order.
1045 */
1046 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1047 reverse_iterator
1048 rend() _GLIBCXX_NOEXCEPT
1049 { return reverse_iterator(begin()); }
1050
1051 /**
1052 * Returns a read-only (constant) reverse iterator that points
1053 * to one before the first element in the %vector. Iteration
1054 * is done in reverse element order.
1055 */
1056 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1057 const_reverse_iterator
1058 rend() const _GLIBCXX_NOEXCEPT
1059 { return const_reverse_iterator(begin()); }
1060
1061#if __cplusplus >= 201103L
1062 /**
1063 * Returns a read-only (constant) iterator that points to the
1064 * first element in the %vector. Iteration is done in ordinary
1065 * element order.
1066 */
1067 [[__nodiscard__]] _GLIBCXX20_CONSTEXPR
1068 const_iterator
1069 cbegin() const noexcept
1070 { return const_iterator(this->_M_impl._M_start); }
1071
1072 /**
1073 * Returns a read-only (constant) iterator that points one past
1074 * the last element in the %vector. Iteration is done in
1075 * ordinary element order.
1076 */
1077 [[__nodiscard__]] _GLIBCXX20_CONSTEXPR
1078 const_iterator
1079 cend() const noexcept
1080 { return const_iterator(this->_M_impl._M_finish); }
1081
1082 /**
1083 * Returns a read-only (constant) reverse iterator that points
1084 * to the last element in the %vector. Iteration is done in
1085 * reverse element order.
1086 */
1087 [[__nodiscard__]] _GLIBCXX20_CONSTEXPR
1088 const_reverse_iterator
1089 crbegin() const noexcept
1090 { return const_reverse_iterator(end()); }
1091
1092 /**
1093 * Returns a read-only (constant) reverse iterator that points
1094 * to one before the first element in the %vector. Iteration
1095 * is done in reverse element order.
1096 */
1097 [[__nodiscard__]] _GLIBCXX20_CONSTEXPR
1098 const_reverse_iterator
1099 crend() const noexcept
1100 { return const_reverse_iterator(begin()); }
1101#endif
1102
1103 // [23.2.4.2] capacity
1104 /** Returns the number of elements in the %vector. */
1105 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1106 size_type
1107 size() const _GLIBCXX_NOEXCEPT
1108 {
1109 ptrdiff_t __dif = this->_M_impl._M_finish - this->_M_impl._M_start;
1110 if (__dif < 0)
1111 __builtin_unreachable();
1112 return size_type(__dif);
1113 }
1114
1115 /** Returns the size() of the largest possible %vector. */
1116 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1117 size_type
1118 max_size() const _GLIBCXX_NOEXCEPT
1119 { return _S_max_size(a: _M_get_Tp_allocator()); }
1120
1121#if __cplusplus >= 201103L
1122 /**
1123 * @brief Resizes the %vector to the specified number of elements.
1124 * @param __new_size Number of elements the %vector should contain.
1125 *
1126 * This function will %resize the %vector to the specified
1127 * number of elements. If the number is smaller than the
1128 * %vector's current size the %vector is truncated, otherwise
1129 * default constructed elements are appended.
1130 */
1131 _GLIBCXX20_CONSTEXPR
1132 void
1133 resize(size_type __new_size)
1134 {
1135 if (__new_size > size())
1136 _M_default_append(n: __new_size - size());
1137 else if (__new_size < size())
1138 _M_erase_at_end(pos: this->_M_impl._M_start + __new_size);
1139 }
1140
1141 /**
1142 * @brief Resizes the %vector to the specified number of elements.
1143 * @param __new_size Number of elements the %vector should contain.
1144 * @param __x Data with which new elements should be populated.
1145 *
1146 * This function will %resize the %vector to the specified
1147 * number of elements. If the number is smaller than the
1148 * %vector's current size the %vector is truncated, otherwise
1149 * the %vector is extended and new elements are populated with
1150 * given data.
1151 */
1152 _GLIBCXX20_CONSTEXPR
1153 void
1154 resize(size_type __new_size, const value_type& __x)
1155 {
1156 if (__new_size > size())
1157 _M_fill_append(n: __new_size - size(), __x);
1158 else if (__new_size < size())
1159 _M_erase_at_end(pos: this->_M_impl._M_start + __new_size);
1160 }
1161#else
1162 /**
1163 * @brief Resizes the %vector to the specified number of elements.
1164 * @param __new_size Number of elements the %vector should contain.
1165 * @param __x Data with which new elements should be populated.
1166 *
1167 * This function will %resize the %vector to the specified
1168 * number of elements. If the number is smaller than the
1169 * %vector's current size the %vector is truncated, otherwise
1170 * the %vector is extended and new elements are populated with
1171 * given data.
1172 */
1173 _GLIBCXX20_CONSTEXPR
1174 void
1175 resize(size_type __new_size, value_type __x = value_type())
1176 {
1177 if (__new_size > size())
1178 _M_fill_append(__new_size - size(), __x);
1179 else if (__new_size < size())
1180 _M_erase_at_end(this->_M_impl._M_start + __new_size);
1181 }
1182#endif
1183
1184#if __cplusplus >= 201103L
1185 /** A non-binding request to reduce capacity() to size(). */
1186 _GLIBCXX20_CONSTEXPR
1187 void
1188 shrink_to_fit()
1189 { _M_shrink_to_fit(); }
1190#endif
1191
1192 /**
1193 * Returns the total number of elements that the %vector can
1194 * hold before needing to allocate more memory.
1195 */
1196 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1197 size_type
1198 capacity() const _GLIBCXX_NOEXCEPT
1199 {
1200 ptrdiff_t __dif = this->_M_impl._M_end_of_storage
1201 - this->_M_impl._M_start;
1202 if (__dif < 0)
1203 __builtin_unreachable();
1204 return size_type(__dif);
1205 }
1206
1207 /**
1208 * Returns true if the %vector is empty. (Thus begin() would
1209 * equal end().)
1210 */
1211 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1212 bool
1213 empty() const _GLIBCXX_NOEXCEPT
1214 { return begin() == end(); }
1215
1216 /**
1217 * @brief Attempt to preallocate enough memory for specified number of
1218 * elements.
1219 * @param __n Number of elements required.
1220 * @throw std::length_error If @a n exceeds @c max_size().
1221 *
1222 * This function attempts to reserve enough memory for the
1223 * %vector to hold the specified number of elements. If the
1224 * number requested is more than max_size(), length_error is
1225 * thrown.
1226 *
1227 * The advantage of this function is that if optimal code is a
1228 * necessity and the user can determine the number of elements
1229 * that will be required, the user can reserve the memory in
1230 * %advance, and thus prevent a possible reallocation of memory
1231 * and copying of %vector data.
1232 */
1233 _GLIBCXX20_CONSTEXPR
1234 void
1235 reserve(size_type __n);
1236
1237 // element access
1238 /**
1239 * @brief Subscript access to the data contained in the %vector.
1240 * @param __n The index of the element for which data should be
1241 * accessed.
1242 * @return Read/write reference to data.
1243 *
1244 * This operator allows for easy, array-style, data access.
1245 * Note that data access with this operator is unchecked and
1246 * out_of_range lookups are not defined. (For checked lookups
1247 * see at().)
1248 */
1249 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1250 reference
1251 operator[](size_type __n) _GLIBCXX_NOEXCEPT
1252 {
1253 __glibcxx_requires_subscript(__n);
1254 return *(this->_M_impl._M_start + __n);
1255 }
1256
1257 /**
1258 * @brief Subscript access to the data contained in the %vector.
1259 * @param __n The index of the element for which data should be
1260 * accessed.
1261 * @return Read-only (constant) reference to data.
1262 *
1263 * This operator allows for easy, array-style, data access.
1264 * Note that data access with this operator is unchecked and
1265 * out_of_range lookups are not defined. (For checked lookups
1266 * see at().)
1267 */
1268 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1269 const_reference
1270 operator[](size_type __n) const _GLIBCXX_NOEXCEPT
1271 {
1272 __glibcxx_requires_subscript(__n);
1273 return *(this->_M_impl._M_start + __n);
1274 }
1275
1276 protected:
1277 /// Safety check used only from at().
1278 _GLIBCXX20_CONSTEXPR
1279 void
1280 _M_range_check(size_type __n) const
1281 {
1282 if (__n >= this->size())
1283 __throw_out_of_range_fmt(__N("vector::_M_range_check: __n "
1284 "(which is %zu) >= this->size() "
1285 "(which is %zu)"),
1286 __n, this->size());
1287 }
1288
1289 public:
1290 /**
1291 * @brief Provides access to the data contained in the %vector.
1292 * @param __n The index of the element for which data should be
1293 * accessed.
1294 * @return Read/write reference to data.
1295 * @throw std::out_of_range If @a __n is an invalid index.
1296 *
1297 * This function provides for safer data access. The parameter
1298 * is first checked that it is in the range of the vector. The
1299 * function throws out_of_range if the check fails.
1300 */
1301 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1302 reference
1303 at(size_type __n)
1304 {
1305 _M_range_check(__n);
1306 return (*this)[__n];
1307 }
1308
1309 /**
1310 * @brief Provides access to the data contained in the %vector.
1311 * @param __n The index of the element for which data should be
1312 * accessed.
1313 * @return Read-only (constant) reference to data.
1314 * @throw std::out_of_range If @a __n is an invalid index.
1315 *
1316 * This function provides for safer data access. The parameter
1317 * is first checked that it is in the range of the vector. The
1318 * function throws out_of_range if the check fails.
1319 */
1320 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1321 const_reference
1322 at(size_type __n) const
1323 {
1324 _M_range_check(__n);
1325 return (*this)[__n];
1326 }
1327
1328 /**
1329 * Returns a read/write reference to the data at the first
1330 * element of the %vector.
1331 */
1332 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1333 reference
1334 front() _GLIBCXX_NOEXCEPT
1335 {
1336 __glibcxx_requires_nonempty();
1337 return *begin();
1338 }
1339
1340 /**
1341 * Returns a read-only (constant) reference to the data at the first
1342 * element of the %vector.
1343 */
1344 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1345 const_reference
1346 front() const _GLIBCXX_NOEXCEPT
1347 {
1348 __glibcxx_requires_nonempty();
1349 return *begin();
1350 }
1351
1352 /**
1353 * Returns a read/write reference to the data at the last
1354 * element of the %vector.
1355 */
1356 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1357 reference
1358 back() _GLIBCXX_NOEXCEPT
1359 {
1360 __glibcxx_requires_nonempty();
1361 return *(end() - 1);
1362 }
1363
1364 /**
1365 * Returns a read-only (constant) reference to the data at the
1366 * last element of the %vector.
1367 */
1368 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1369 const_reference
1370 back() const _GLIBCXX_NOEXCEPT
1371 {
1372 __glibcxx_requires_nonempty();
1373 return *(end() - 1);
1374 }
1375
1376 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1377 // DR 464. Suggestion for new member functions in standard containers.
1378 // data access
1379 /**
1380 * Returns a pointer such that [data(), data() + size()) is a valid
1381 * range. For a non-empty %vector, data() == &front().
1382 */
1383 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1384 _Tp*
1385 data() _GLIBCXX_NOEXCEPT
1386 { return _M_data_ptr(this->_M_impl._M_start); }
1387
1388 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
1389 const _Tp*
1390 data() const _GLIBCXX_NOEXCEPT
1391 { return _M_data_ptr(this->_M_impl._M_start); }
1392
1393 // [23.2.4.3] modifiers
1394 /**
1395 * @brief Add data to the end of the %vector.
1396 * @param __x Data to be added.
1397 *
1398 * This is a typical stack operation. The function creates an
1399 * element at the end of the %vector and assigns the given data
1400 * to it. Due to the nature of a %vector this operation can be
1401 * done in constant time if the %vector has preallocated space
1402 * available.
1403 */
1404 _GLIBCXX20_CONSTEXPR
1405 void
1406 push_back(const value_type& __x)
1407 {
1408 if (this->_M_impl._M_finish != this->_M_impl._M_end_of_storage)
1409 {
1410 _GLIBCXX_ASAN_ANNOTATE_GROW(1);
1411 _Alloc_traits::construct(this->_M_impl, this->_M_impl._M_finish,
1412 __x);
1413 ++this->_M_impl._M_finish;
1414 _GLIBCXX_ASAN_ANNOTATE_GREW(1);
1415 }
1416 else
1417 _M_realloc_append(__x);
1418 }
1419
1420#if __cplusplus >= 201103L
1421 _GLIBCXX20_CONSTEXPR
1422 void
1423 push_back(value_type&& __x)
1424 { emplace_back(std::move(__x)); }
1425
1426 template<typename... _Args>
1427#if __cplusplus > 201402L
1428 _GLIBCXX20_CONSTEXPR
1429 reference
1430#else
1431 void
1432#endif
1433 emplace_back(_Args&&... __args);
1434#endif
1435
1436 /**
1437 * @brief Removes last element.
1438 *
1439 * This is a typical stack operation. It shrinks the %vector by one.
1440 *
1441 * Note that no data is returned, and if the last element's
1442 * data is needed, it should be retrieved before pop_back() is
1443 * called.
1444 */
1445 _GLIBCXX20_CONSTEXPR
1446 void
1447 pop_back() _GLIBCXX_NOEXCEPT
1448 {
1449 __glibcxx_requires_nonempty();
1450 --this->_M_impl._M_finish;
1451 _Alloc_traits::destroy(this->_M_impl, this->_M_impl._M_finish);
1452 _GLIBCXX_ASAN_ANNOTATE_SHRINK(1);
1453 }
1454
1455#if __cplusplus >= 201103L
1456 /**
1457 * @brief Inserts an object in %vector before specified iterator.
1458 * @param __position A const_iterator into the %vector.
1459 * @param __args Arguments.
1460 * @return An iterator that points to the inserted data.
1461 *
1462 * This function will insert an object of type T constructed
1463 * with T(std::forward<Args>(args)...) before the specified location.
1464 * Note that this kind of operation could be expensive for a %vector
1465 * and if it is frequently used the user should consider using
1466 * std::list.
1467 */
1468 template<typename... _Args>
1469 _GLIBCXX20_CONSTEXPR
1470 iterator
1471 emplace(const_iterator __position, _Args&&... __args)
1472 { return _M_emplace_aux(__position, std::forward<_Args>(__args)...); }
1473
1474 /**
1475 * @brief Inserts given value into %vector before specified iterator.
1476 * @param __position A const_iterator into the %vector.
1477 * @param __x Data to be inserted.
1478 * @return An iterator that points to the inserted data.
1479 *
1480 * This function will insert a copy of the given value before
1481 * the specified location. Note that this kind of operation
1482 * could be expensive for a %vector and if it is frequently
1483 * used the user should consider using std::list.
1484 */
1485 _GLIBCXX20_CONSTEXPR
1486 iterator
1487 insert(const_iterator __position, const value_type& __x);
1488#else
1489 /**
1490 * @brief Inserts given value into %vector before specified iterator.
1491 * @param __position An iterator into the %vector.
1492 * @param __x Data to be inserted.
1493 * @return An iterator that points to the inserted data.
1494 *
1495 * This function will insert a copy of the given value before
1496 * the specified location. Note that this kind of operation
1497 * could be expensive for a %vector and if it is frequently
1498 * used the user should consider using std::list.
1499 */
1500 iterator
1501 insert(iterator __position, const value_type& __x);
1502#endif
1503
1504#if __cplusplus >= 201103L
1505 /**
1506 * @brief Inserts given rvalue into %vector before specified iterator.
1507 * @param __position A const_iterator into the %vector.
1508 * @param __x Data to be inserted.
1509 * @return An iterator that points to the inserted data.
1510 *
1511 * This function will insert a copy of the given rvalue before
1512 * the specified location. Note that this kind of operation
1513 * could be expensive for a %vector and if it is frequently
1514 * used the user should consider using std::list.
1515 */
1516 _GLIBCXX20_CONSTEXPR
1517 iterator
1518 insert(const_iterator __position, value_type&& __x)
1519 { return _M_insert_rval(__position, v: std::move(__x)); }
1520
1521 /**
1522 * @brief Inserts an initializer_list into the %vector.
1523 * @param __position An iterator into the %vector.
1524 * @param __l An initializer_list.
1525 *
1526 * This function will insert copies of the data in the
1527 * initializer_list @a l into the %vector before the location
1528 * specified by @a position.
1529 *
1530 * Note that this kind of operation could be expensive for a
1531 * %vector and if it is frequently used the user should
1532 * consider using std::list.
1533 */
1534 _GLIBCXX20_CONSTEXPR
1535 iterator
1536 insert(const_iterator __position, initializer_list<value_type> __l)
1537 {
1538 auto __offset = __position - cbegin();
1539 _M_range_insert(begin() + __offset, __l.begin(), __l.end(),
1540 std::random_access_iterator_tag());
1541 return begin() + __offset;
1542 }
1543#endif
1544
1545#if __cplusplus >= 201103L
1546 /**
1547 * @brief Inserts a number of copies of given data into the %vector.
1548 * @param __position A const_iterator into the %vector.
1549 * @param __n Number of elements to be inserted.
1550 * @param __x Data to be inserted.
1551 * @return An iterator that points to the inserted data.
1552 *
1553 * This function will insert a specified number of copies of
1554 * the given data before the location specified by @a position.
1555 *
1556 * Note that this kind of operation could be expensive for a
1557 * %vector and if it is frequently used the user should
1558 * consider using std::list.
1559 */
1560 _GLIBCXX20_CONSTEXPR
1561 iterator
1562 insert(const_iterator __position, size_type __n, const value_type& __x)
1563 {
1564 difference_type __offset = __position - cbegin();
1565 _M_fill_insert(pos: begin() + __offset, __n, __x);
1566 return begin() + __offset;
1567 }
1568#else
1569 /**
1570 * @brief Inserts a number of copies of given data into the %vector.
1571 * @param __position An iterator into the %vector.
1572 * @param __n Number of elements to be inserted.
1573 * @param __x Data to be inserted.
1574 *
1575 * This function will insert a specified number of copies of
1576 * the given data before the location specified by @a position.
1577 *
1578 * Note that this kind of operation could be expensive for a
1579 * %vector and if it is frequently used the user should
1580 * consider using std::list.
1581 */
1582 void
1583 insert(iterator __position, size_type __n, const value_type& __x)
1584 { _M_fill_insert(__position, __n, __x); }
1585#endif
1586
1587#if __cplusplus >= 201103L
1588 /**
1589 * @brief Inserts a range into the %vector.
1590 * @param __position A const_iterator into the %vector.
1591 * @param __first An input iterator.
1592 * @param __last An input iterator.
1593 * @return An iterator that points to the inserted data.
1594 *
1595 * This function will insert copies of the data in the range
1596 * [__first,__last) into the %vector before the location specified
1597 * by @a pos.
1598 *
1599 * Note that this kind of operation could be expensive for a
1600 * %vector and if it is frequently used the user should
1601 * consider using std::list.
1602 */
1603 template<typename _InputIterator,
1604 typename = std::_RequireInputIter<_InputIterator>>
1605 _GLIBCXX20_CONSTEXPR
1606 iterator
1607 insert(const_iterator __position, _InputIterator __first,
1608 _InputIterator __last)
1609 {
1610 difference_type __offset = __position - cbegin();
1611 _M_range_insert(begin() + __offset, __first, __last,
1612 std::__iterator_category(__first));
1613 return begin() + __offset;
1614 }
1615#else
1616 /**
1617 * @brief Inserts a range into the %vector.
1618 * @param __position An iterator into the %vector.
1619 * @param __first An input iterator.
1620 * @param __last An input iterator.
1621 *
1622 * This function will insert copies of the data in the range
1623 * [__first,__last) into the %vector before the location specified
1624 * by @a pos.
1625 *
1626 * Note that this kind of operation could be expensive for a
1627 * %vector and if it is frequently used the user should
1628 * consider using std::list.
1629 */
1630 template<typename _InputIterator>
1631 void
1632 insert(iterator __position, _InputIterator __first,
1633 _InputIterator __last)
1634 {
1635 // Check whether it's an integral type. If so, it's not an iterator.
1636 typedef typename std::__is_integer<_InputIterator>::__type _Integral;
1637 _M_insert_dispatch(__position, __first, __last, _Integral());
1638 }
1639#endif
1640
1641#if __glibcxx_containers_ranges // C++ >= 23
1642 /**
1643 * @brief Insert a range into the vector.
1644 * @param __rg A range of values that are convertible to `value_type`.
1645 * @return An iterator that points to the first new element inserted,
1646 * or to `__pos` if `__rg` is an empty range.
1647 * @pre `__rg` and `*this` do not overlap.
1648 * @since C++23
1649 */
1650 template<__detail::__container_compatible_range<_Tp> _Rg>
1651 constexpr iterator
1652 insert_range(const_iterator __pos, _Rg&& __rg);
1653
1654 /**
1655 * @brief Append a range at the end of the vector.
1656 * @param __rg A range of values that are convertible to `value_type`.
1657 * @since C++23
1658 */
1659 template<__detail::__container_compatible_range<_Tp> _Rg>
1660 constexpr void
1661 append_range(_Rg&& __rg)
1662 {
1663 // N.B. __rg may overlap with *this, so we must copy from __rg before
1664 // existing elements or iterators referring to *this are invalidated.
1665 // e.g. in v.append_range(views::concat(v, foo)) rg overlaps v.
1666 if constexpr (ranges::forward_range<_Rg> || ranges::sized_range<_Rg>)
1667 {
1668 const auto __n = size_type(ranges::distance(__rg));
1669
1670 // If there is no existing storage, there are no iterators that
1671 // can be referring to our storage, so it's safe to allocate now.
1672 if (capacity() == 0)
1673 reserve(__n);
1674
1675 const auto __sz = size();
1676 const auto __capacity = capacity();
1677 if ((__capacity - __sz) >= __n)
1678 {
1679 _GLIBCXX_ASAN_ANNOTATE_GROW(__n);
1680 _Base::_M_append_range(__rg);
1681 _GLIBCXX_ASAN_ANNOTATE_GREW(__n);
1682 return;
1683 }
1684
1685 const size_type __len = _M_check_len(__n, "vector::append_range");
1686
1687 pointer __old_start = this->_M_impl._M_start;
1688 pointer __old_finish = this->_M_impl._M_finish;
1689
1690 allocator_type& __a = _M_get_Tp_allocator();
1691 const pointer __start = this->_M_allocate(__len);
1692 const pointer __mid = __start + __sz;
1693 const pointer __back = __mid + __n;
1694 _Guard_alloc __guard(__start, __len, *this);
1695 std::__uninitialized_copy_a(ranges::begin(__rg),
1696 ranges::end(__rg),
1697 __mid, __a);
1698
1699 if constexpr (_S_use_relocate())
1700 _S_relocate(__old_start, __old_finish, __start, __a);
1701 else
1702 {
1703 // RAII type to destroy initialized elements.
1704 struct _Guard_elts
1705 {
1706 pointer _M_first, _M_last; // Elements to destroy
1707 _Tp_alloc_type& _M_alloc;
1708
1709 constexpr
1710 _Guard_elts(pointer __f, pointer __l, _Tp_alloc_type& __a)
1711 : _M_first(__f), _M_last(__l), _M_alloc(__a)
1712 { }
1713
1714 constexpr
1715 ~_Guard_elts()
1716 { std::_Destroy(_M_first, _M_last, _M_alloc); }
1717
1718 _Guard_elts(_Guard_elts&&) = delete;
1719 };
1720 _Guard_elts __guard_elts{__mid, __back, __a};
1721
1722 std::__uninitialized_move_a(__old_start, __old_finish,
1723 __start, __a);
1724
1725 // Let old elements get destroyed by __guard_elts:
1726 __guard_elts._M_first = __old_start;
1727 __guard_elts._M_last = __old_finish;
1728 }
1729
1730 // Now give ownership of old storage to __guard:
1731 __guard._M_storage = __old_start;
1732 __guard._M_len = __capacity;
1733 // Finally, take ownership of new storage:
1734 this->_M_impl._M_start = __start;
1735 this->_M_impl._M_finish = __back;
1736 this->_M_impl._M_end_of_storage = __start + __len;
1737 }
1738 else
1739 {
1740 auto __first = ranges::begin(__rg);
1741 const auto __last = ranges::end(__rg);
1742
1743 // Fill up to the end of current capacity.
1744 for (auto __free = capacity() - size();
1745 __first != __last && __free > 0;
1746 ++__first, (void) --__free)
1747 emplace_back(*__first);
1748
1749 if (__first == __last)
1750 return;
1751
1752 // Copy the rest of the range to a new vector.
1753 vector __tmp(_M_get_Tp_allocator());
1754 for (; __first != __last; ++__first)
1755 __tmp.emplace_back(*__first);
1756 reserve(_M_check_len(__tmp.size(), "vector::append_range"));
1757 ranges::subrange __r(std::make_move_iterator(__tmp.begin()),
1758 std::make_move_iterator(__tmp.end()));
1759 append_range(__r); // This will take the fast path above.
1760 }
1761 }
1762#endif // containers_ranges
1763
1764 /**
1765 * @brief Remove element at given position.
1766 * @param __position Iterator pointing to element to be erased.
1767 * @return An iterator pointing to the next element (or end()).
1768 *
1769 * This function will erase the element at the given position and thus
1770 * shorten the %vector by one.
1771 *
1772 * Note This operation could be expensive and if it is
1773 * frequently used the user should consider using std::list.
1774 * The user is also cautioned that this function only erases
1775 * the element, and that if the element is itself a pointer,
1776 * the pointed-to memory is not touched in any way. Managing
1777 * the pointer is the user's responsibility.
1778 */
1779 _GLIBCXX20_CONSTEXPR
1780 iterator
1781#if __cplusplus >= 201103L
1782 erase(const_iterator __position)
1783 { return _M_erase(begin() + (__position - cbegin())); }
1784#else
1785 erase(iterator __position)
1786 { return _M_erase(__position); }
1787#endif
1788
1789 /**
1790 * @brief Remove a range of elements.
1791 * @param __first Iterator pointing to the first element to be erased.
1792 * @param __last Iterator pointing to one past the last element to be
1793 * erased.
1794 * @return An iterator pointing to the element pointed to by @a __last
1795 * prior to erasing (or end()).
1796 *
1797 * This function will erase the elements in the range
1798 * [__first,__last) and shorten the %vector accordingly.
1799 *
1800 * Note This operation could be expensive and if it is
1801 * frequently used the user should consider using std::list.
1802 * The user is also cautioned that this function only erases
1803 * the elements, and that if the elements themselves are
1804 * pointers, the pointed-to memory is not touched in any way.
1805 * Managing the pointer is the user's responsibility.
1806 */
1807 _GLIBCXX20_CONSTEXPR
1808 iterator
1809#if __cplusplus >= 201103L
1810 erase(const_iterator __first, const_iterator __last)
1811 {
1812 const auto __beg = begin();
1813 const auto __cbeg = cbegin();
1814 return _M_erase(__beg + (__first - __cbeg), __beg + (__last - __cbeg));
1815 }
1816#else
1817 erase(iterator __first, iterator __last)
1818 { return _M_erase(__first, __last); }
1819#endif
1820
1821 /**
1822 * @brief Swaps data with another %vector.
1823 * @param __x A %vector of the same element and allocator types.
1824 *
1825 * This exchanges the elements between two vectors in constant time.
1826 * (Three pointers, so it should be quite fast.)
1827 * Note that the global std::swap() function is specialized such that
1828 * std::swap(v1,v2) will feed to this function.
1829 *
1830 * Whether the allocators are swapped depends on the allocator traits.
1831 */
1832 _GLIBCXX20_CONSTEXPR
1833 void
1834 swap(vector& __x) _GLIBCXX_NOEXCEPT
1835 {
1836#if __cplusplus >= 201103L
1837 __glibcxx_assert(_Alloc_traits::propagate_on_container_swap::value
1838 || _M_get_Tp_allocator() == __x._M_get_Tp_allocator());
1839#endif
1840 this->_M_impl._M_swap_data(__x._M_impl);
1841 _Alloc_traits::_S_on_swap(_M_get_Tp_allocator(),
1842 __x._M_get_Tp_allocator());
1843 }
1844
1845 /**
1846 * Erases all the elements. Note that this function only erases the
1847 * elements, and that if the elements themselves are pointers, the
1848 * pointed-to memory is not touched in any way. Managing the pointer is
1849 * the user's responsibility.
1850 */
1851 _GLIBCXX20_CONSTEXPR
1852 void
1853 clear() _GLIBCXX_NOEXCEPT
1854 { _M_erase_at_end(pos: this->_M_impl._M_start); }
1855
1856 private:
1857 // RAII guard for allocated storage.
1858 struct _Guard_alloc
1859 {
1860 pointer _M_storage; // Storage to deallocate
1861 size_type _M_len;
1862 _Base& _M_vect;
1863
1864 _GLIBCXX20_CONSTEXPR
1865 _Guard_alloc(pointer __s, size_type __l, _Base& __vect)
1866 : _M_storage(__s), _M_len(__l), _M_vect(__vect)
1867 { }
1868
1869 _GLIBCXX20_CONSTEXPR
1870 ~_Guard_alloc()
1871 {
1872 if (_M_storage)
1873 _M_vect._M_deallocate(_M_storage, _M_len);
1874 }
1875
1876 _GLIBCXX20_CONSTEXPR
1877 pointer
1878 _M_release()
1879 {
1880 pointer __res = _M_storage;
1881 _M_storage = pointer();
1882 return __res;
1883 }
1884
1885 private:
1886 _Guard_alloc(const _Guard_alloc&);
1887 };
1888
1889 protected:
1890 /**
1891 * Memory expansion handler. Uses the member allocation function to
1892 * obtain @a n bytes of memory, and then copies [first,last) into it.
1893 */
1894 template<typename _ForwardIterator>
1895 _GLIBCXX20_CONSTEXPR
1896 pointer
1897 _M_allocate_and_copy(size_type __n,
1898 _ForwardIterator __first, _ForwardIterator __last)
1899 {
1900 _Guard_alloc __guard(this->_M_allocate(__n), __n, *this);
1901 std::__uninitialized_copy_a
1902 (__first, __last, __guard._M_storage, _M_get_Tp_allocator());
1903 return __guard._M_release();
1904 }
1905
1906
1907 // Internal constructor functions follow.
1908
1909 // Called by the range constructor to implement [23.1.1]/9
1910
1911#if __cplusplus < 201103L
1912 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1913 // 438. Ambiguity in the "do the right thing" clause
1914 template<typename _Integer>
1915 void
1916 _M_initialize_dispatch(_Integer __int_n, _Integer __value, __true_type)
1917 {
1918 const size_type __n = static_cast<size_type>(__int_n);
1919 pointer __start =
1920 _M_allocate(_S_check_init_len(__n, _M_get_Tp_allocator()));
1921 this->_M_impl._M_start = __start;
1922 this->_M_impl._M_end_of_storage = __start + __n;
1923 _M_fill_initialize(__n, __value);
1924 }
1925
1926 // Called by the range constructor to implement [23.1.1]/9
1927 template<typename _InputIterator>
1928 void
1929 _M_initialize_dispatch(_InputIterator __first, _InputIterator __last,
1930 __false_type)
1931 {
1932 _M_range_initialize(__first, __last,
1933 std::__iterator_category(__first));
1934 }
1935#endif
1936
1937 // Called by the second initialize_dispatch above
1938 template<typename _InputIterator>
1939 _GLIBCXX20_CONSTEXPR
1940 void
1941 _M_range_initialize(_InputIterator __first, _InputIterator __last,
1942 std::input_iterator_tag)
1943 {
1944 __try {
1945 for (; __first != __last; ++__first)
1946#if __cplusplus >= 201103L
1947 emplace_back(*__first);
1948#else
1949 push_back(*__first);
1950#endif
1951 } __catch(...) {
1952 clear();
1953 __throw_exception_again;
1954 }
1955 }
1956
1957 // Called by the second initialize_dispatch above
1958 template<typename _ForwardIterator>
1959 _GLIBCXX20_CONSTEXPR
1960 void
1961 _M_range_initialize(_ForwardIterator __first, _ForwardIterator __last,
1962 std::forward_iterator_tag)
1963 {
1964 _M_range_initialize_n(__first, __last,
1965 std::distance(__first, __last));
1966 }
1967
1968 template<typename _Iterator, typename _Sentinel>
1969 _GLIBCXX20_CONSTEXPR
1970 void
1971 _M_range_initialize_n(_Iterator __first, _Sentinel __last,
1972 size_type __n)
1973 {
1974 pointer __start =
1975 this->_M_allocate(_S_check_init_len(__n, a: _M_get_Tp_allocator()));
1976 this->_M_impl._M_start = this->_M_impl._M_finish = __start;
1977 this->_M_impl._M_end_of_storage = __start + __n;
1978 this->_M_impl._M_finish
1979 = std::__uninitialized_copy_a(_GLIBCXX_MOVE(__first), __last,
1980 __start, _M_get_Tp_allocator());
1981 }
1982
1983 // Called by the first initialize_dispatch above and by the
1984 // vector(n,value,a) constructor.
1985 _GLIBCXX20_CONSTEXPR
1986 void
1987 _M_fill_initialize(size_type __n, const value_type& __value)
1988 {
1989 this->_M_impl._M_finish =
1990 std::__uninitialized_fill_n_a(this->_M_impl._M_start, __n, __value,
1991 _M_get_Tp_allocator());
1992 }
1993
1994#if __cplusplus >= 201103L
1995 // Called by the vector(n) constructor.
1996 _GLIBCXX20_CONSTEXPR
1997 void
1998 _M_default_initialize(size_type __n)
1999 {
2000 this->_M_impl._M_finish =
2001 std::__uninitialized_default_n_a(this->_M_impl._M_start, __n,
2002 _M_get_Tp_allocator());
2003 }
2004#endif
2005
2006 // Internal assign functions follow. The *_aux functions do the actual
2007 // assignment work for the range versions.
2008
2009 // Called by the range assign to implement [23.1.1]/9
2010
2011 // _GLIBCXX_RESOLVE_LIB_DEFECTS
2012 // 438. Ambiguity in the "do the right thing" clause
2013 template<typename _Integer>
2014 _GLIBCXX20_CONSTEXPR
2015 void
2016 _M_assign_dispatch(_Integer __n, _Integer __val, __true_type)
2017 { _M_fill_assign(__n, __val); }
2018
2019 // Called by the range assign to implement [23.1.1]/9
2020 template<typename _InputIterator>
2021 _GLIBCXX20_CONSTEXPR
2022 void
2023 _M_assign_dispatch(_InputIterator __first, _InputIterator __last,
2024 __false_type)
2025 { _M_assign_aux(__first, __last, std::__iterator_category(__first)); }
2026
2027 // Called by the second assign_dispatch above
2028 template<typename _InputIterator>
2029 _GLIBCXX20_CONSTEXPR
2030 void
2031 _M_assign_aux(_InputIterator __first, _InputIterator __last,
2032 std::input_iterator_tag);
2033
2034 // Called by the second assign_dispatch above
2035 template<typename _ForwardIterator>
2036 _GLIBCXX20_CONSTEXPR
2037 void
2038 _M_assign_aux(_ForwardIterator __first, _ForwardIterator __last,
2039 std::forward_iterator_tag);
2040
2041 // Called by assign(n,t), and the range assign when it turns out
2042 // to be the same thing.
2043 _GLIBCXX20_CONSTEXPR
2044 void
2045 _M_fill_assign(size_type __n, const value_type& __val);
2046
2047 // Internal insert functions follow.
2048
2049 // Called by the range insert to implement [23.1.1]/9
2050
2051 // _GLIBCXX_RESOLVE_LIB_DEFECTS
2052 // 438. Ambiguity in the "do the right thing" clause
2053 template<typename _Integer>
2054 _GLIBCXX20_CONSTEXPR
2055 void
2056 _M_insert_dispatch(iterator __pos, _Integer __n, _Integer __val,
2057 __true_type)
2058 { _M_fill_insert(__pos, __n, x: __val); }
2059
2060 // Called by the range insert to implement [23.1.1]/9
2061 template<typename _InputIterator>
2062 _GLIBCXX20_CONSTEXPR
2063 void
2064 _M_insert_dispatch(iterator __pos, _InputIterator __first,
2065 _InputIterator __last, __false_type)
2066 {
2067 _M_range_insert(__pos, __first, __last,
2068 std::__iterator_category(__first));
2069 }
2070
2071 // Called by the second insert_dispatch above
2072 template<typename _InputIterator>
2073 _GLIBCXX20_CONSTEXPR
2074 void
2075 _M_range_insert(iterator __pos, _InputIterator __first,
2076 _InputIterator __last, std::input_iterator_tag);
2077
2078 // Called by the second insert_dispatch above
2079 template<typename _ForwardIterator>
2080 _GLIBCXX20_CONSTEXPR
2081 void
2082 _M_range_insert(iterator __pos, _ForwardIterator __first,
2083 _ForwardIterator __last, std::forward_iterator_tag);
2084
2085 // Called by insert(p,n,x), and the range insert when it turns out to be
2086 // the same thing.
2087 _GLIBCXX20_CONSTEXPR
2088 void
2089 _M_fill_insert(iterator __pos, size_type __n, const value_type& __x);
2090
2091 // Called by resize(n,x), and the _M_fill_insert(end(), n, x)
2092 _GLIBCXX20_CONSTEXPR
2093 void
2094 _M_fill_append(size_type __n, const value_type& __x);
2095
2096#if __cplusplus >= 201103L
2097 // Called by resize(n).
2098 _GLIBCXX20_CONSTEXPR
2099 void
2100 _M_default_append(size_type __n);
2101
2102 _GLIBCXX20_CONSTEXPR
2103 bool
2104 _M_shrink_to_fit();
2105#endif
2106
2107#if __cplusplus < 201103L
2108 // Called by insert(p,x)
2109 void
2110 _M_insert_aux(iterator __position, const value_type& __x);
2111
2112 void
2113 _M_realloc_insert(iterator __position, const value_type& __x);
2114
2115 void
2116 _M_realloc_append(const value_type& __x);
2117#else
2118 // A value_type object constructed with _Alloc_traits::construct()
2119 // and destroyed with _Alloc_traits::destroy().
2120 struct _Temporary_value
2121 {
2122 template<typename... _Args>
2123 _GLIBCXX20_CONSTEXPR explicit
2124 _Temporary_value(vector* __vec, _Args&&... __args) : _M_this(__vec)
2125 {
2126 _Alloc_traits::construct(_M_this->_M_impl, _M_ptr(),
2127 std::forward<_Args>(__args)...);
2128 }
2129
2130 _GLIBCXX20_CONSTEXPR
2131 ~_Temporary_value()
2132 { _Alloc_traits::destroy(_M_this->_M_impl, _M_ptr()); }
2133
2134 _GLIBCXX20_CONSTEXPR value_type&
2135 _M_val() noexcept { return _M_storage._M_val; }
2136
2137 private:
2138 _GLIBCXX20_CONSTEXPR _Tp*
2139 _M_ptr() noexcept { return std::__addressof(_M_storage._M_val); }
2140
2141 union _Storage
2142 {
2143 constexpr _Storage() : _M_byte() { }
2144 _GLIBCXX20_CONSTEXPR ~_Storage() { }
2145 _Storage& operator=(const _Storage&) = delete;
2146 unsigned char _M_byte;
2147 _Tp _M_val;
2148 };
2149
2150 vector* _M_this;
2151 _Storage _M_storage;
2152 };
2153
2154 // Called by insert(p,x) and other functions when insertion needs to
2155 // reallocate or move existing elements. _Arg is either _Tp& or _Tp.
2156 template<typename _Arg>
2157 _GLIBCXX20_CONSTEXPR
2158 void
2159 _M_insert_aux(iterator __position, _Arg&& __arg);
2160
2161 template<typename... _Args>
2162 _GLIBCXX20_CONSTEXPR
2163 void
2164 _M_realloc_insert(iterator __position, _Args&&... __args);
2165
2166 template<typename... _Args>
2167 _GLIBCXX20_CONSTEXPR
2168 void
2169 _M_realloc_append(_Args&&... __args);
2170
2171 // Either move-construct at the end, or forward to _M_insert_aux.
2172 _GLIBCXX20_CONSTEXPR
2173 iterator
2174 _M_insert_rval(const_iterator __position, value_type&& __v);
2175
2176 // Try to emplace at the end, otherwise forward to _M_insert_aux.
2177 template<typename... _Args>
2178 _GLIBCXX20_CONSTEXPR
2179 iterator
2180 _M_emplace_aux(const_iterator __position, _Args&&... __args);
2181
2182 // Emplacing an rvalue of the correct type can use _M_insert_rval.
2183 _GLIBCXX20_CONSTEXPR
2184 iterator
2185 _M_emplace_aux(const_iterator __position, value_type&& __v)
2186 { return _M_insert_rval(__position, v: std::move(__v)); }
2187#endif
2188
2189 // Called by _M_fill_insert, _M_insert_aux etc.
2190 _GLIBCXX20_CONSTEXPR
2191 size_type
2192 _M_check_len(size_type __n, const char* __s) const
2193 {
2194 if (max_size() - size() < __n)
2195 __throw_length_error(__N(__s));
2196
2197 const size_type __len = size() + (std::max)(size(), __n);
2198 return (__len < size() || __len > max_size()) ? max_size() : __len;
2199 }
2200
2201 // Called by constructors to check initial size.
2202 static _GLIBCXX20_CONSTEXPR size_type
2203 _S_check_init_len(size_type __n, const allocator_type& __a)
2204 {
2205 if (__n > _S_max_size(a: _Tp_alloc_type(__a)))
2206 __throw_length_error(
2207 __N("cannot create std::vector larger than max_size()"));
2208 return __n;
2209 }
2210
2211 static _GLIBCXX20_CONSTEXPR size_type
2212 _S_max_size(const _Tp_alloc_type& __a) _GLIBCXX_NOEXCEPT
2213 {
2214 // std::distance(begin(), end()) cannot be greater than PTRDIFF_MAX,
2215 // and realistically we can't store more than PTRDIFF_MAX/sizeof(T)
2216 // (even if std::allocator_traits::max_size says we can).
2217 const size_t __diffmax
2218 = __gnu_cxx::__numeric_traits<ptrdiff_t>::__max / sizeof(_Tp);
2219 const size_t __allocmax = _Alloc_traits::max_size(__a);
2220 return (std::min)(a: __diffmax, b: __allocmax);
2221 }
2222
2223 // Internal erase functions follow.
2224
2225 // Called by erase(q1,q2), clear(), resize(), _M_fill_assign,
2226 // _M_assign_aux.
2227 _GLIBCXX20_CONSTEXPR
2228 void
2229 _M_erase_at_end(pointer __pos) _GLIBCXX_NOEXCEPT
2230 {
2231 if (size_type __n = this->_M_impl._M_finish - __pos)
2232 {
2233 std::_Destroy(__pos, this->_M_impl._M_finish,
2234 _M_get_Tp_allocator());
2235 this->_M_impl._M_finish = __pos;
2236 _GLIBCXX_ASAN_ANNOTATE_SHRINK(__n);
2237 }
2238 }
2239
2240 _GLIBCXX20_CONSTEXPR
2241 iterator
2242 _M_erase(iterator __position);
2243
2244 _GLIBCXX20_CONSTEXPR
2245 iterator
2246 _M_erase(iterator __first, iterator __last);
2247
2248#if __cplusplus >= 201103L
2249 private:
2250 // Constant-time move assignment when source object's memory can be
2251 // moved, either because the source's allocator will move too
2252 // or because the allocators are equal.
2253 _GLIBCXX20_CONSTEXPR
2254 void
2255 _M_move_assign(vector&& __x, true_type) noexcept
2256 {
2257 vector __tmp(get_allocator());
2258 this->_M_impl._M_swap_data(__x._M_impl);
2259 __tmp._M_impl._M_swap_data(__x._M_impl);
2260 std::__alloc_on_move(_M_get_Tp_allocator(), __x._M_get_Tp_allocator());
2261 }
2262
2263 // Do move assignment when it might not be possible to move source
2264 // object's memory, resulting in a linear-time operation.
2265 _GLIBCXX20_CONSTEXPR
2266 void
2267 _M_move_assign(vector&& __x, false_type)
2268 {
2269 if (__x._M_get_Tp_allocator() == this->_M_get_Tp_allocator())
2270 _M_move_assign(std::move(__x), true_type());
2271 else
2272 {
2273 // The rvalue's allocator cannot be moved and is not equal,
2274 // so we need to individually move each element.
2275 this->_M_assign_aux(std::make_move_iterator(__x.begin()),
2276 std::make_move_iterator(__x.end()),
2277 std::random_access_iterator_tag());
2278 __x.clear();
2279 }
2280 }
2281#endif
2282
2283 template<typename _Up>
2284 _GLIBCXX20_CONSTEXPR
2285 _Up*
2286 _M_data_ptr(_Up* __ptr) const _GLIBCXX_NOEXCEPT
2287 { return __ptr; }
2288
2289#if __cplusplus >= 201103L
2290 template<typename _Ptr>
2291 _GLIBCXX20_CONSTEXPR
2292 typename std::pointer_traits<_Ptr>::element_type*
2293 _M_data_ptr(_Ptr __ptr) const
2294 { return empty() ? nullptr : std::__to_address(__ptr); }
2295#else
2296 template<typename _Ptr>
2297 value_type*
2298 _M_data_ptr(_Ptr __ptr) const
2299 { return empty() ? (value_type*)0 : __ptr.operator->(); }
2300#endif
2301 };
2302
2303#if __cpp_deduction_guides >= 201606
2304 template<typename _InputIterator, typename _ValT
2305 = typename iterator_traits<_InputIterator>::value_type,
2306 typename _Allocator = allocator<_ValT>,
2307 typename = _RequireInputIter<_InputIterator>,
2308 typename = _RequireAllocator<_Allocator>>
2309 vector(_InputIterator, _InputIterator, _Allocator = _Allocator())
2310 -> vector<_ValT, _Allocator>;
2311
2312#if __glibcxx_containers_ranges // C++ >= 23
2313 template<ranges::input_range _Rg,
2314 typename _Alloc = allocator<ranges::range_value_t<_Rg>>>
2315 vector(from_range_t, _Rg&&, _Alloc = _Alloc())
2316 -> vector<ranges::range_value_t<_Rg>, _Alloc>;
2317#endif
2318#endif
2319
2320 /**
2321 * @brief Vector equality comparison.
2322 * @param __x A %vector.
2323 * @param __y A %vector of the same type as @a __x.
2324 * @return True iff the size and elements of the vectors are equal.
2325 *
2326 * This is an equivalence relation. It is linear in the size of the
2327 * vectors. Vectors are considered equivalent if their sizes are equal,
2328 * and if corresponding elements compare equal.
2329 */
2330 template<typename _Tp, typename _Alloc>
2331 _GLIBCXX_NODISCARD _GLIBCXX20_CONSTEXPR
2332 inline bool
2333 operator==(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
2334 { return (__x.size() == __y.size()
2335 && std::equal(__x.begin(), __x.end(), __y.begin())); }
2336
2337#if __cpp_lib_three_way_comparison // >= C++20
2338 /**
2339 * @brief Vector ordering relation.
2340 * @param __x A `vector`.
2341 * @param __y A `vector` of the same type as `__x`.
2342 * @return A value indicating whether `__x` is less than, equal to,
2343 * greater than, or incomparable with `__y`.
2344 *
2345 * See `std::lexicographical_compare_three_way()` for how the determination
2346 * is made. This operator is used to synthesize relational operators like
2347 * `<` and `>=` etc.
2348 */
2349 template<typename _Tp, typename _Alloc>
2350 [[nodiscard]]
2351 constexpr __detail::__synth3way_t<_Tp>
2352 operator<=>(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
2353 {
2354 return std::lexicographical_compare_three_way(__x.begin(), __x.end(),
2355 __y.begin(), __y.end(),
2356 __detail::__synth3way);
2357 }
2358#else
2359 /**
2360 * @brief Vector ordering relation.
2361 * @param __x A %vector.
2362 * @param __y A %vector of the same type as @a __x.
2363 * @return True iff @a __x is lexicographically less than @a __y.
2364 *
2365 * This is a total ordering relation. It is linear in the size of the
2366 * vectors. The elements must be comparable with @c <.
2367 *
2368 * See std::lexicographical_compare() for how the determination is made.
2369 */
2370 template<typename _Tp, typename _Alloc>
2371 _GLIBCXX_NODISCARD inline bool
2372 operator<(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
2373 { return std::lexicographical_compare(__x.begin(), __x.end(),
2374 __y.begin(), __y.end()); }
2375
2376 /// Based on operator==
2377 template<typename _Tp, typename _Alloc>
2378 _GLIBCXX_NODISCARD inline bool
2379 operator!=(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
2380 { return !(__x == __y); }
2381
2382 /// Based on operator<
2383 template<typename _Tp, typename _Alloc>
2384 _GLIBCXX_NODISCARD inline bool
2385 operator>(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
2386 { return __y < __x; }
2387
2388 /// Based on operator<
2389 template<typename _Tp, typename _Alloc>
2390 _GLIBCXX_NODISCARD inline bool
2391 operator<=(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
2392 { return !(__y < __x); }
2393
2394 /// Based on operator<
2395 template<typename _Tp, typename _Alloc>
2396 _GLIBCXX_NODISCARD inline bool
2397 operator>=(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
2398 { return !(__x < __y); }
2399#endif // three-way comparison
2400
2401 /// See std::vector::swap().
2402 template<typename _Tp, typename _Alloc>
2403 _GLIBCXX20_CONSTEXPR
2404 inline void
2405 swap(vector<_Tp, _Alloc>& __x, vector<_Tp, _Alloc>& __y)
2406 _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y)))
2407 { __x.swap(__y); }
2408
2409_GLIBCXX_END_NAMESPACE_CONTAINER
2410
2411#if __cplusplus >= 201703L
2412 namespace __detail::__variant
2413 {
2414 template<typename> struct _Never_valueless_alt; // see <variant>
2415
2416 // Provide the strong exception-safety guarantee when emplacing a
2417 // vector into a variant, but only if move assignment cannot throw.
2418 template<typename _Tp, typename _Alloc>
2419 struct _Never_valueless_alt<_GLIBCXX_STD_C::vector<_Tp, _Alloc>>
2420 : std::is_nothrow_move_assignable<_GLIBCXX_STD_C::vector<_Tp, _Alloc>>
2421 { };
2422 } // namespace __detail::__variant
2423#endif // C++17
2424
2425_GLIBCXX_END_NAMESPACE_VERSION
2426} // namespace std
2427
2428#endif /* _STL_VECTOR_H */
2429