Memory model

Use this hub to reason about memory visibility and ownership in modern C++. Start from language guarantees, then connect them to atomics, fences, and allocator/resource APIs. The goal is a practical model for writing lock-free and lock-based code safely.

# Mental Model Diagram

Key idea: release/acquire creates a synchronization edge; synchronization contributes to happens-before; happens-before constrains what reads may observe.

# Language Semantics

• C++ memory model
• Object lifetime
• new-expression

# Ownership and Smart Pointers

• Memory utilities overview
• std::unique_ptr
• std::shared_ptr
• std::weak_ptr

# Allocation and Resources

• Allocator requirements and APIs
• std::pmr::memory_resource
• Global operator new/delete

# Concurrency-Safe Memory Ordering

• std::memory_order
• std::atomic_thread_fence

# Fast Entry Points

• Start here for rules: C++ memory model
• Then ordering details: std::memory_order
• Then ownership APIs: Memory utilities overview