https://github.com/jcfr/stackoverflow-56135785-answer

Answer to stackoverflow question 56135785
https://github.com/jcfr/stackoverflow-56135785-answer

stackoverflow-answer

Last synced: 1 day ago
JSON representation

Answer to stackoverflow question 56135785

• Host: GitHub
• URL: https://github.com/jcfr/stackoverflow-56135785-answer
• Owner: jcfr
• Created: 2019-05-25T14:48:04.000Z (over 5 years ago)
• Default Branch: master
• Last Pushed: 2019-05-25T16:44:41.000Z (over 5 years ago)
• Last Synced: 2024-11-24T07:42:05.532Z (2 months ago)
• Topics: stackoverflow-answer
• Language: CMake
• Homepage: https://stackoverflow.com/questions/56135785/correctly-set-the-location-of-imported-cmake-targets-for-an-installed-package
• Size: 21.5 KB
• Stars: 4
• Watchers: 3
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE_CC-BY-SA-4.0.md

Awesome Lists containing this project

README

        
This project was created to help answer Stackoverflow question 56135785.

See https://stackoverflow.com/questions/56135785/correctly-set-the-location-of-imported-cmake-targets-for-an-installed-package

It improves the sample code originally submitted by user [bruce-adams](https://stackoverflow.com/users/1569204/bruce-adams)

and provides some recommendations to better organize the associated CMake project.

### ChangeLog summarizing edits

* 2019-05-25

  * Create GitHub project to streamline reuse and adaptation. See https://github.com/jcfr/stackoverflow-56135785-answer

  * Rename project and source directory from `foobar` to `FooBarLib`, update [Suggestions](#suggestions) section accordingly

  * Improve `build.sh`

  * Updated suggestions (`CPACK_PACKAGING_INSTALL_PREFIX` should indeed be absolute to properly impact RPM layout)

  * RPM:

     * Be aware that setting `CPACK_PACKAGING_INSTALL_PREFIX` also impact the layout of the `TGZ` archive, this propably

       not what you want.

     * Update `build.sh` to display content of RPM package

     * `CPACK_PACKAGING_INSTALL_PREFIX` is set to `/opt`

### Remarks

* Two config files should be generated:

  * one for the build tree: this allow user of your project to directly build against your project and import targets

  * one for the install tree (which also end up being packaged)

* Do not force the value of `CMAKE_INSTALL_PREFIX`

* `CPACK_PACKAGING_INSTALL_PREFIX` should NOT be set to an absolute directory

* For sake of consistency, use `foobarTargets` instead of `foobarLibTargets`

* `` placeholder used below correspond to the name of the project upper-cased (`ABC` instead of `abc`)

* To allow configuring your project when vendorized along other one, prefer variable with `_`. This means `_INSTALL_LIBRARY_DIR` is better than `LIBRARY_INSTALL_DIR`.

* To allow user of the project to configure `*_INSTALL_DIR` variables, wrap them around `if(DEFINED ...)`

* Consistently use variables (e.g `LIBRARY_INSTALL_DIR` should always be used instead of `lib`)

* Prefer naming variable `_INSTALL_*_DIR` instead of `_*_INSTALL_DIR`, it make it easier to know the purpose of the variable when reading the code.

* Since version is already associated with the project, there is no need to set `VERSION` variable. Instead, you can use `PROJECT_VERSION` or `FOOBAR_VERSION`

* If starting a new project, prefer the most recent CMake version. CMake 3.13 instead of CMake 3.7

* Introduced variable `_INSTALL_CONFIG_DIR`

* `Targets.cmake` should not be installed using `install(FILES ...)`,  it is already associated with an install rule

* conditionally set `CMAKE_INSTALL_RPATH`, it is valid only on Linux

* `Config.cmake.in`:

  * there is no need to set `FOOBAR_LIBRARY`, this information is already associated with the exported `foobar` target

  * FOOBAR_LIBRARY_DIR is also not needed, this information is already associated with the exported `foobar` target

  * instead of setting FOOBAR_INCLUDE_DIR, the command `target_include_directories` should be used

  * remove setting of `FOOBAR_VERSION`, the generate version file already takes care of setting the version.

* always specify ARCHIVE, LIBRARY and RUNTIME when declaring install rules for target. It avoid issue when switching library type. One less thing to think about.

* always specify component with your install rule. It allows user of your project to selectively install part of it only development component or only runtime one, ...

* initializing `CMAKE_BUILD_TYPE` is also important,  it ensures the generated Targets file are associated with a configuration (instead of having the suffix `-noconfig.cmake`)