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std::pmr::polymorphic_allocator::allocate(3) | C++ Standard Libary | std::pmr::polymorphic_allocator::allocate(3) |
NAME¶
std::pmr::polymorphic_allocator::allocate - std::pmr::polymorphic_allocator::allocate
Synopsis¶
T* allocate( std::size_t n ); (since C++17)
(until C++20)
[[nodiscard]] T* allocate( std::size_t n ); (since C++20)
Allocates storage for n objects of type T using the underlying memory
resource.
Equivalent to return static_cast<T*>(resource()->allocate(n *
sizeof(T),
alignof(T)));.
Parameters¶
n - the number of objects to allocate storage for
Return value¶
A pointer to the allocated storage.
Exceptions¶
Throws std::bad_array_new_length if n >
std::numeric_limits<std::size_t>::max() /
sizeof(T); may also throw any exceptions thrown by the call to
resource()->allocate.
Defect reports
The following behavior-changing defect reports were applied retroactively to
previously published C++ standards.
DR Applied to Behavior as published Correct behavior
LWG 3038 C++17 allocate might allocate storage of wrong throws length_error
size instead
LWG 3237 C++17 the exception thrown by allocate was made consistent
inconsistent with std::allocator::allocate
See also¶
allocate_bytes Allocate raw aligned memory from the underlying
resource
(C++20) (public member function)
allocate_object Allocates raw memory suitable for an object or an array
(C++20) (public member function)
new_object Allocates and constructs an object
(C++20) (public member function)
allocate allocates uninitialized storage using the allocator
[static] (public static member function of
std::allocator_traits<Alloc>)
allocate allocates memory
(public member function of std::pmr::memory_resource)
2022.07.31 | http://cppreference.com |