16 — Tooling: CMake, Debuggers, Sanitizers, Testing

Core Idea

Modern C++ skill includes tooling. Real C++ work is not just language syntax.

Compiler Flags

Start with strict warnings:

-Wall -Wextra -Wpedantic

During learning, consider:

-Werror

Debug build:

-g -O0

Release build:

-O2

CMake

Minimal project:

cmake_minimum_required(VERSION 3.20)
project(myapp LANGUAGES CXX)

set(CMAKE_CXX_STANDARD 20)
set(CMAKE_CXX_STANDARD_REQUIRED ON)

add_executable(myapp src/main.cpp)

Build:

cmake -S . -B build
cmake --build build
./build/myapp

Debuggers

Use gdb or lldb.

Basic gdb commands:

break main
run
next
step
print variable
backtrace
continue

Sanitizers

Address + UB sanitizer:

-fsanitize=address,undefined -fno-omit-frame-pointer -g

Thread sanitizer:

-fsanitize=thread -g

Use sanitizers regularly during development.

Formatting

Use clang-format to avoid style arguments.

clang-format -i src/*.cpp include/*.hpp

Static Analysis

Use clang-tidy to catch suspicious patterns.

clang-tidy src/main.cpp -- -std=c++20

Testing

Popular options:

• Catch2,
• GoogleTest,
• doctest.

Tiny standard-library smoke test:

#include <cassert>

void test_addition() {
    assert(add(2, 3) == 5);
}

Package Managers

Common C++ package managers:

• vcpkg,
• Conan.

You do not need them on day one, but real projects often use them.

Recommended Development Setup

• C++20 compiler: GCC or Clang.
• CMake.
• Ninja or Make.
• gdb/lldb.
• clang-format.
• clang-tidy.
• sanitizers.
• Catch2 or GoogleTest.

Quick Self-Test

You should be able to answer:

• How do you build a CMake project?
• How do you set a breakpoint?
• What does AddressSanitizer catch?
• Why use clang-format?
• What is the difference between debug and release builds?