CMake Useful Variables: Difference between revisions

From KitwarePublic
Jump to navigationJump to search
(Replace content with link to new CMake community wiki)
 
(112 intermediate revisions by 36 users not shown)
Line 1: Line 1:
CMake uses and defines several variables, which can be used in CMakeLists.txt files.
{{CMake/Template/Moved}}


== Locations ==
This page has moved [https://gitlab.kitware.com/cmake/community/wikis/doc/cmake/Useful-Variables here].
 
; CMAKE_SOURCE_DIR : this is the directory, from which cmake was started, i.e. the top level source directory
; CMAKE_CURRENT_SOURCE_DIR : this is the directory where the currently processed  CMakeLists.txt is located in
; CMAKE_BINARY_DIR : if you are building in-source, this is the same as CMAKE_SOURCE_DIR, otherwise this is the top level directory of your build tree
; CMAKE_CURRENT_BINARY_DIR : if you are building in-source, this is the same as CMAKE_CURRENT_SOURCE_DIR, otherwise this is the directory where the compiled or generated files from the current CMakeLists.txt will go to
; CMAKE_ROOT : this is the CMake installation directory
; PROJECT_SOURCE_DIR : contains the full path to root of your project source directory.
; PROJECT_BINARY_DIR : contains the full path to the top level directory of your build tree.
; LIBRARY_OUTPUT_PATH : set this variable to specify a common place where cmake should put all libraries.
<tt>SET(LIBRARY_OUTPUT_PATH ${PROJECT_BINARY_DIR}/lib)</tt>
; EXECUTABLE_OUTPUT_PATH : set this variable to specify a common place where cmake should pull all executable files.
<tt>SET(EXECUTABLE_OUTPUT_PATH ${PROJECT_BINARY_DIR}/bin)</tt>
 
== Various Options ==
; CMAKE_SKIP_RULE_DEPENDENCY : set this to true if you don't want to rebuild the object files if the rules have changed, but not the actual source files or headers (e.g. if you changed the some compiler switches)
; CMAKE_VERBOSE_MAKEFILE : set this to true if you are using makefiles and want to see the full compile and link commands instead of only the shortened ones
; CMAKE_SKIP_INSTALL_ALL_DEPENDENCY : since CMake 2.1 the install rule depends on all, i.e. everything will be built before installing. If you don't like this, set this one to true.
; CMAKE_SUPPRESS_REGENERATION : this will cause CMake to not put in the rules that re-run CMake. This might be useful if you  want to use the generated build files on another machine.
 
== Compilers and Tools ==
 
A simple way to get switches to the compiler is to use ADD_DEFINITIONS(). But there are also two variables exactly for this purpose:
 
; CMAKE_C_FLAGS : the compiler flags for compiling C sources
; CMAKE_CXX_FLAGS : the compiler flags for compiling C++ sources
 
The following variables are detected during the cmake run and set accordingly (e.g. to gcc). If you want to force the use of other tools, you can set these variables manually to the desired tools. E.g. if you want to use the gcc cross compiling toolchain for arm processors, you could do the following: SET(CMAKE_C_COMPILER arm-elf-gcc)
 
; CMAKE_C_COMPILER : the compiler used for C files
; CMAKE_CXX_COMPILER : the compiler used for C++ files
; CMAKE_COMPILER_IS_GNUCC : if the compiler is a variant of gcc, this should be set to 1
; CMAKE_COMPILER_IS_GNUCXX : if the compiler is a variant of g++, this should be set to 1
; CMAKE_AR, CMAKE_RANLIB : the tools for creating libraries
 
== Build  rules ==
 
Build rules are defined in CMakeCInformation.cmake and CMakeCXXInformation.cmake.
 
Rules for C++ sources:
 
* CMAKE_CXX_CREATE_SHARED_LIBRARY
* CMAKE_CXX_CREATE_SHARED_MODULE
* CMAKE_CXX_CREATE_STATIC_LIBRARY
* CMAKE_CXX_COMPILE_OBJECT
* CMAKE_CXX_LINK_EXECUTABLE
 
and the equivalents for C sources:
 
* CMAKE_C_CREATE_SHARED_LIBRARY
* CMAKE_C_CREATE_SHARED_MODULE
* CMAKE_C_CREATE_STATIC_LIBRARY
* CMAKE_C_COMPILE_OBJECT
* CMAKE_C_LINK_EXECUTABLE
 
You can override the variables manually, e.g. replacing some flags in the linker command, but you can't change the value of the variables in sharp braces. Usually you don't have to change these rules, only in rare cases. You should only do this if you know what you are doing and there is no other way.

Latest revision as of 15:41, 30 April 2018


The CMake community Wiki has moved to the Kitware GitLab Instance.

This page has moved here.