clang-tidy and static analysis

Worked example

Read it before you run it

cmake -S . -B build -DCMAKE_EXPORT_COMPILE_COMMANDS=ON
# Configure and write build/compile_commands.json, the list of exact compiler commands.
clang-tidy -p build src/main.cpp
# Analyse one file using the compile commands in build/.
clang-tidy -p build --checks='bugprone-*,performance-*,modernize-*' src/main.cpp
# Run only selected groups of checks.
clang-tidy -p build --fix src/main.cpp
# Apply the automatic fixes (commit first so you can review the diff).
clang-format -i src/main.cpp
# Reformat the file in place using the project style.
cppcheck --enable=warning,style --std=c++17 src
# A second, independent analyser for a different set of findings.

Practice code

Now type it yourself

Copy the starter into practice.cpp and replace every TODO with your own code. Build and run it: g++ -std=c++17 -Wall -Wextra -Wpedantic practice.cpp -o practice -pthread && ./practice

// Run: clang-tidy -p build --checks='modernize-*,bugprone-*' tidy.cpp
#include <iostream>
#include <vector>

int main() {
  // TODO: use nullptr instead of NULL and a range-based for loop with const auto& (modernize checks)
  (void)unused;
  std::cout << sum << '\n';
  return 0;
}

6

// Run: clang-tidy -p build --checks='modernize-*,bugprone-*' tidy.cpp
#include <iostream>
#include <vector>

int main() {
  const int* unused = nullptr;
  std::vector<int> values{1, 2, 3};
  int sum = 0;
  for (const auto& v : values) sum += v;
  (void)unused;
  std::cout << sum << '\n';
  return 0;
}