Namespaces
Variants
Views
Actions

std::allocator<T>::construct

From cppreference.com
< cpp‎ | memory‎ | allocator
 
 
Dynamic memory management
Uninitialized memory algorithms
Constrained uninitialized memory algorithms
Allocators
Garbage collection support
(C++11)(until C++23)
(C++11)(until C++23)
(C++11)(until C++23)
(C++11)(until C++23)
(C++11)(until C++23)
(C++11)(until C++23)



 
std::allocator
Member functions
(until C++20)
(until C++20)
allocator::construct
(until C++20)
(until C++20)
Non-member functions
 
Defined in header <memory>
void construct( pointer p, const_reference val );
(1) (until C++11)
template< class U, class... Args >
void construct( U* p, Args&&... args );
(2) (since C++11)
(deprecated in C++17)
(removed in C++20)

Constructs an object of type T in allocated uninitialized storage pointed to by p, using global placement-new.

1) Calls ::new((void*)p) T(val).
2) Calls ::new((void*)p) U(std::forward<Args>(args)...).

Contents

[edit] Parameters

p - pointer to allocated uninitialized storage
val - the value to use as the copy constructor argument
args... - the constructor arguments to use

[edit] Return value

(none)

[edit] 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 402 C++98 if T::operator new exists, the program might be ill-formed uses global replacement-new instead

[edit] See also

[static]
constructs an object in the allocated storage
(function template) [edit]
creates an object at a given address
(function template) [edit]
allocation functions
(function) [edit]