https://knightli.com/en/tags/cmake-basics/ Recent content in Cmake-Basics on KnightLi Blog Hugo -- gohugo.io en Fri, 28 Mar 2025 00:00:00 +0000 https://knightli.com/en/2025/03/28/cmake-basics-and-templates/ Fri, 28 Mar 2025 00:00:00 +0000 https://knightli.com/en/2025/03/28/cmake-basics-and-templates/ <h2 id="what-is-cmake">What Is CMake </h2><p>CMake is a cross-platform build system generator. You write <code>CMakeLists.txt</code> once, then generate platform-specific build files (Makefile, Ninja files, Visual Studio projects, and more).</p> <p>On Linux, a typical workflow is:</p> <ol> <li>Write <code>CMakeLists.txt</code></li> <li>Generate build system</li> <li>Build</li> </ol> <div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span><span class="lnt">2 </span><span class="lnt">3 </span><span class="lnt">4 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-bash" data-lang="bash"><span class="line"><span class="cl">mkdir build </span></span><span class="line"><span class="cl"><span class="nb">cd</span> build </span></span><span class="line"><span class="cl">cmake .. </span></span><span class="line"><span class="cl">make </span></span></code></pre></td></tr></table> </div> </div><h2 id="template-1-single-source-file">Template 1: Single Source File </h2><div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span><span class="lnt">2 </span><span class="lnt">3 </span><span class="lnt">4 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-cmake" data-lang="cmake"><span class="line"><span class="cl"><span class="nb">cmake_minimum_required</span><span class="p">(</span><span class="s">VERSION</span> <span class="s">3.5</span><span class="p">)</span><span class="err"> </span></span></span><span class="line"><span class="cl"><span class="nb">project</span><span class="p">(</span><span class="s">Demo1</span><span class="p">)</span><span class="err"> </span></span></span><span class="line"><span class="cl"><span class="err"> </span></span></span><span class="line"><span class="cl"><span class="nb">add_executable</span><span class="p">(</span><span class="s">demo1</span> <span class="s">test01.cpp</span><span class="p">)</span><span class="err"> </span></span></span></code></pre></td></tr></table> </div> </div><h2 id="template-2-multiple-source-files">Template 2: Multiple Source Files </h2><div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span><span class="lnt">2 </span><span class="lnt">3 </span><span class="lnt">4 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-cmake" data-lang="cmake"><span class="line"><span class="cl"><span class="nb">cmake_minimum_required</span><span class="p">(</span><span class="s">VERSION</span> <span class="s">3.5</span><span class="p">)</span><span class="err"> </span></span></span><span class="line"><span class="cl"><span class="nb">project</span><span class="p">(</span><span class="s">Demo2</span><span class="p">)</span><span class="err"> </span></span></span><span class="line"><span class="cl"><span class="err"> </span></span></span><span class="line"><span class="cl"><span class="nb">add_executable</span><span class="p">(</span><span class="s">demo2</span> <span class="s">main.cpp</span> <span class="s">utils.cpp</span><span class="p">)</span><span class="err"> </span></span></span></code></pre></td></tr></table> </div> </div><h2 id="template-3-include-directories--libraries">Template 3: Include Directories + Libraries </h2><div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span><span class="lnt">2 </span><span class="lnt">3 </span><span class="lnt">4 </span><span class="lnt">5 </span><span class="lnt">6 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-cmake" data-lang="cmake"><span class="line"><span class="cl"><span class="nb">cmake_minimum_required</span><span class="p">(</span><span class="s">VERSION</span> <span class="s">3.5</span><span class="p">)</span><span class="err"> </span></span></span><span class="line"><span class="cl"><span class="nb">project</span><span class="p">(</span><span class="s">Demo3</span><span class="p">)</span><span class="err"> </span></span></span><span class="line"><span class="cl"><span class="err"> </span></span></span><span class="line"><span class="cl"><span class="nb">include_directories</span><span class="p">(</span><span class="s">include</span><span class="p">)</span><span class="err"> </span></span></span><span class="line"><span class="cl"><span class="nb">add_executable</span><span class="p">(</span><span class="s">demo3</span> <span class="s">src/main.cpp</span> <span class="s">src/foo.cpp</span><span class="p">)</span><span class="err"> </span></span></span><span class="line"><span class="cl"><span class="nb">target_link_libraries</span><span class="p">(</span><span class="s">demo3</span> <span class="s">pthread</span><span class="p">)</span><span class="err"> </span></span></span></code></pre></td></tr></table> </div> </div><h2 id="recommended-project-structure">Recommended Project Structure </h2><div class="highlight"><div class="chroma"> <table class="lntable"><tr><td class="lntd"> <pre tabindex="0" class="chroma"><code><span class="lnt">1 </span><span class="lnt">2 </span><span class="lnt">3 </span><span class="lnt">4 </span><span class="lnt">5 </span></code></pre></td> <td class="lntd"> <pre tabindex="0" class="chroma"><code class="language-text" data-lang="text"><span class="line"><span class="cl">project/ </span></span><span class="line"><span class="cl"> CMakeLists.txt </span></span><span class="line"><span class="cl"> src/ </span></span><span class="line"><span class="cl"> include/ </span></span><span class="line"><span class="cl"> build/ </span></span></code></pre></td></tr></table> </div> </div><h2 id="tips">Tips </h2><ul> <li>Keep out-of-source builds (<code>build/</code>) to avoid polluting source tree.</li> <li>Use <code>target_*</code> commands (<code>target_include_directories</code>, <code>target_link_libraries</code>) for modern CMake style.</li> <li>Pin a minimum CMake version to avoid compatibility surprises.</li> </ul>