C++ Core Guidelines

Overview

These guidelines help write C++ code that is:

• Type-safe: No implicit violations of the type system
• Resource-safe: No leaks (memory, handles, locks, etc.)
• Performant: Efficient without sacrificing correctness
• Correct: Catches more logic errors at compile time

Load Reference by Scenario

Choose the reference file based on what you're doing:

Scenario	Reference File	Rules
Checking memory leaks, RAII, pointers	memory-safety.md	R., ES., Con.*
Designing function signatures, APIs	api-design.md	I., F.
Designing or reviewing classes	class-design.md	C.*
Thread safety, data races, locks	concurrency.md	CP.*
Exceptions, error codes, error handling	error-handling.md	E.*
Templates, STL, generic code	templates.md	T., SL., Enum.*
Coding style, naming, philosophy	modern-style.md	P., NL., SF.*
Performance optimization, C compatibility	performance.md	Per., CPL., A.*

Quick Reference

Memory Safety

// Bad: manual management
X* p = new X;
delete p;

// Good: RAII
auto p = make_unique<X>();

API Design

// Bad: unclear ownership
void process(int* data, int n);

// Good: explicit ownership and size
void process(span<const int> data);

Class Design

// Rule of zero - let compiler generate
class Widget {
    unique_ptr<Impl> pImpl;  // No explicit dtor/copy/move needed
};

Concurrency

// Bad: manual lock
mutex mtx;
mtx.lock();
// ...
mtx.unlock();

// Good: RAII lock
lock_guard<mutex> lock(mtx);

Code Review Checklist

When reviewing C++ code, load the appropriate reference and check:

Memory Safety → memory-safety.md

• No raw new/delete
• RAII for all resources
• No dangling pointers
• Proper const usage

API Design → api-design.md

• Interfaces are explicit
• Parameters express ownership
• Return values over output params

Class Design → class-design.md

• Class has clear invariant
• Rule of zero/five followed
• Virtual destructor for base classes

Thread Safety → concurrency.md

• No data races
• lock_guard/scoped_lock used
• No deadlocks