imgogl.blogg.se - Cmake command

#CMAKE COMMAND HOW TO#

It is however only recommended for development use.Ĭmake_print_variables(MYVAR CMAKE_MAJOR_VERSION DOES_NOT_EXIST) The only thing you need to do is include the module and it will expose a function named cmake_print_variables where you list the names of the variables you want to debug. While you could use the message command, CMake provides a handy module named CMakePrintHelpers which makes this process a bit easier. You might find yourself needing to debug the value of variables. set(NUMBER_LIST 1 2 "3 4") # Results in NUMBER_LIST="1 2 3 4" list(APPEND NUMBER_LIST 1) # Results in NUMBER_LIST="1 2 3 4 1" list(REMOVE_DUPLICATES NUMBER_LIST 1) # Results in NUMBER_LIST="1 2 3 4" set(NOT_A_LIST "a\ b") # Results in NOT_A_LIST="a\ b" CMakePrintHelpers

Such variables can then be considered as lists and can be more easily manipulated through the list command. Note that if you have multiple values in the set command, they will be concatenated into a single string and seperated by which means that if you pass the variable to a list aware command, you need to escape any unless you want to split your string. The PARENT_SCOPE parameter lets you set the value of a variable in the parent scope (parent function or parent directory), which can serve as an output parameter. The signature of the set function is the following: set(.

Persistent cache: A variable stored in the cache can be seen in the entire build tree.

This applies when using add_subdirectory but not when using include. It will be available to child directories but not parent directories.

Directory: A variable set outside of a function will have the scope of the current CMakeLists.txt directory.

Function scope: A variable defined in a function can not be seen after the function has returned.

Variables are case sensitive and can have any of the following scope: The primary command for variables manipulation is set. Like most imperative languages, CMake provides variables, control flow and even functions.Īll variables are internally handled as strings but can be interpreted differently based on the command using it. When writing build scripts you might quickly find yourself needing variables to provide more control over the configuration of your project.

#CMAKE COMMAND HOW TO#

We will see how to use variables, build configurations and then generator expressions so that you can provide flexible options to your users. Those can be based on the target platform, compiler, or simply based on the user choice. This is an important part of CMake as every project has its own set of requirements. We will now dive deeper and look into more advanced features so that you can customize your project. If you are not familiar with CMake, please read the previous article first. In the previous article we saw the basics of CMake and how to handle targets.