All Uninitialized-Memory Helpers

All Uninitialized-Memory Helpers

A compact index of raw-storage construction, destruction, and uninitialized algorithms used in low-level library code.

How to use this reference page

Use reference pages to confirm names, categories, nearby facilities, and the constraints that matter before writing or reviewing code.

Scan the top of the page first to identify the primary types, functions, or algorithm families involved.
Use the nearby-page links when your question is really about a companion header, related algorithm family, or broader subsystem.
Validate tricky behavior with a small compileable example before relying on memory for details like invalidation, ordering, allocation, or lifetime rules.

All Uninitialized-Memory Helpers

Construction into raw storage

std::construct_at
std::uninitialized_default_construct
std::uninitialized_default_construct_n
std::uninitialized_value_construct
std::uninitialized_value_construct_n
std::uninitialized_fill
std::uninitialized_fill_n
std::uninitialized_copy
std::uninitialized_copy_n
std::uninitialized_move
std::uninitialized_move_n

Destruction helpers

std::destroy_at
std::destroy
std::destroy_n

Allocation-adjacent helpers

std::allocator_traits
std::to_address
placement new from <new>
std::launder

Practical rules

These utilities are mainly for container, allocator, and low-level library implementations.
Prefer ordinary object construction unless you are deliberately managing raw storage.
Keep exception safety explicit when partially constructed ranges are possible.

Example in practice

#include <memory>

int main() {
    auto owner = std::make_unique<int>(42);
    auto shared = std::make_shared<int>(*owner);
    owner.reset();
    return *shared;
}