Merge branch '10_presets' into 'main'

add example for cmake presets

See merge request !5

.gitlab-ci.yml

@@ -48,6 +48,13 @@ check-recipes:
     - cmake --build 08_build
     - ctest --test-dir 08_build || FAILED=true
 
+    - cmake --preset dev -S 10_presets -B 10_dev
+    - cmake --build 10_dev
+    - ./10_dev/app
+    - cmake --preset production -S 10_presets -B 10_production
+    - cmake --build 10_production
+    - ./10_production/app
+
 check-links:
   before_script:
     - module purge

10_presets/CMakeLists.txt

+cmake_minimum_required(VERSION 3.20)
+
+project(10_presets
+        LANGUAGES CXX)
+
+add_executable(app main.cpp)
+

10_presets/CMakePresets.json

+{
+  "version": 3,
+  "cmakeMinimumRequired": {
+    "major": 3,
+    "minor": 20,
+    "patch": 0
+  },
+  "configurePresets": [
+    {
+      "name": "dev",
+      "displayName": "development settings",
+      "generator": "Unix Makefiles",
+      "cacheVariables": {
+        "CMAKE_CXX_COMPILER": "g++",
+        "CMAKE_CXX_FLAGS": "-Wall -Wextra"
+      }
+    },
+    {
+      "name": "production",
+      "displayName": "production settings",
+      "generator": "Unix Makefiles",
+      "cacheVariables": {
+        "CMAKE_CXX_COMPILER": "g++",
+        "CMAKE_CXX_FLAGS": "-march=native"
+      }
+    }
+  ]
+}

10_presets/README.md

+# How to add compilation configurations to your project?
+
+## Brief
+[Presets](https://cmake.org/cmake/help/latest/manual/cmake-presets.7.html) are able to replace your custom shell scripts that build your application on different platforms with different settings. Since 3.19 CMake supports presets.
+
+## Description
+Presets are based on two main files.
+ * `CMakePresets.json` holds the project-wide presets that are checked into the repository.
+ * `CMakeUserPresets.json` contains developer specific settings and should not be part of the repository.\
+        (In fact, you should at it to your `.gitignore` file.)
+
+Presets have a name and specify flags for the configure, build, test, install, etc stage.
+To invoke a preset configuration during the configure stage use e.g.
+`cmake --preset <ConfigurePreset> -S <SourceDirectory> -B <BuildDirectory>`
+or during the build stage use
+`cmake --preset <BuildPreset> --build <BuildDirectory>`.
+
+## Example
+This recipe contains two configure presets as an example. The development preset can be selected like this,
+`cmake --preset dev -S <SourceDirectory> -B <BuildDirectory>`. It uses `g++` as a compiler and enables compiler warnings.
+If you build you will see a warning printed. In contrast, the `production` preset does not enable compiler warnings,
+but optimization flags. A build with this configuration does not show warnings.
\ No newline at end of file

10_presets/main.cpp

+#include <iostream>
+
+int main()
+{
+    int a;
+    std::cout << a << std::endl;
+}

README.md

@@ -18,6 +18,7 @@ we run them in our CI.
  * [How to get the current git hash at configure time?](06_git_configure)
  * [How to get the current git hash at build time?](07_git_build)
  * [How to manage all the tests in your project?](08_ctest)
+ * [How to add compilation configurations to your project?](10_presets)
 
 ## Why CMake?
  * Automatically search for programs, libraries, and header files