CMAKE(1) | CMake | CMAKE(1) |
cmake - CMake Command-Line Reference
Generate a Project Buildsystem
cmake [<options>] <path-to-source>
cmake [<options>] <path-to-existing-build>
cmake [<options>] -S <path-to-source> -B <path-to-build> Build a Project
cmake --build <dir> [<options>] [-- <build-tool-options>] Install a Project
cmake --install <dir> [<options>] Open a Project
cmake --open <dir> Run a Script
cmake [{-D <var>=<value>}...] -P <cmake-script-file> Run a Command-Line Tool
cmake -E <command> [<options>] Run the Find-Package Tool
cmake --find-package [<options>] View Help
cmake --help[-<topic>]
The cmake executable is the command-line interface of the cross-platform buildsystem generator CMake. The above Synopsis lists various actions the tool can perform as described in sections below.
To build a software project with CMake, Generate a Project Buildsystem. Optionally use cmake to Build a Project, Install a Project or just run the corresponding build tool (e.g. make) directly. cmake can also be used to View Help.
The other actions are meant for use by software developers writing scripts in the CMake language to support their builds.
For graphical user interfaces that may be used in place of cmake, see ccmake and cmake-gui. For command-line interfaces to the CMake testing and packaging facilities, see ctest and cpack.
For more information on CMake at large, see also the links at the end of this manual.
A buildsystem describes how to build a project’s executables and libraries from its source code using a build tool to automate the process. For example, a buildsystem may be a Makefile for use with a command-line make tool or a project file for an Integrated Development Environment (IDE). In order to avoid maintaining multiple such buildsystems, a project may specify its buildsystem abstractly using files written in the CMake language. From these files CMake generates a preferred buildsystem locally for each user through a backend called a generator.
To generate a buildsystem with CMake, the following must be selected:
To maintain a pristine source tree, perform an out-of-source build by using a separate dedicated build tree. An in-source build in which the build tree is placed in the same directory as the source tree is also supported, but discouraged.
When using one of the Command-Line Build Tool Generators CMake expects that the environment needed by the compiler toolchain is already configured in the shell. When using one of the IDE Build Tool Generators, no particular environment is needed.
Run CMake with one of the following command signatures to specify the source and build trees and generate a buildsystem:
$ mkdir build ; cd build $ cmake ../src
$ cd build $ cmake .
$ cmake -S src -B build
In all cases the <options> may be zero or more of the Options below.
After generating a buildsystem one may use the corresponding native build tool to build the project. For example, after using the Unix Makefiles generator one may run make directly:
$ make $ make install
Alternatively, one may use cmake to Build a Project by automatically choosing and invoking the appropriate native build tool.
If the directory doesn’t already exist CMake will make it.
When CMake is first run in an empty build tree, it creates a CMakeCache.txt file and populates it with customizable settings for the project. This option may be used to specify a file from which to load cache entries before the first pass through the project’s CMake listfiles. The loaded entries take priority over the project’s default values. The given file should be a CMake script containing set() commands that use the CACHE option, not a cache-format file.
References to CMAKE_SOURCE_DIR and CMAKE_BINARY_DIR within the script evaluate to the top-level source and build tree.
When CMake is first run in an empty build tree, it creates a CMakeCache.txt file and populates it with customizable settings for the project. This option may be used to specify a setting that takes priority over the project’s default value. The option may be repeated for as many CACHE entries as desired.
If the :<type> portion is given it must be one of the types specified by the set() command documentation for its CACHE signature. If the :<type> portion is omitted the entry will be created with no type if it does not exist with a type already. If a command in the project sets the type to PATH or FILEPATH then the <value> will be converted to an absolute path.
This option may also be given as a single argument: -D<var>:<type>=<value> or -D<var>=<value>.
This option may be used to remove one or more variables from the CMakeCache.txt file, globbing expressions using * and ? are supported. The option may be repeated for as many CACHE entries as desired.
Use with care, you can make your CMakeCache.txt non-working.
CMake may support multiple native build systems on certain platforms. A generator is responsible for generating a particular build system. Possible generator names are specified in the cmake-generators(7) manual.
If not specified, CMake checks the CMAKE_GENERATOR environment variable and otherwise falls back to a builtin default selection.
Some CMake generators support a toolset specification to tell the native build system how to choose a compiler. See the CMAKE_GENERATOR_TOOLSET variable for details.
Some CMake generators support a platform name to be given to the native build system to choose a compiler or SDK. See the CMAKE_GENERATOR_PLATFORM variable for details.
Suppress warnings that are meant for the author of the CMakeLists.txt files. By default this will also turn off deprecation warnings.
Enable warnings that are meant for the author of the CMakeLists.txt files. By default this will also turn on deprecation warnings.
Make warnings that are meant for the author of the CMakeLists.txt files errors. By default this will also turn on deprecated warnings as errors.
Make warnings that are meant for the author of the CMakeLists.txt files not errors. By default this will also turn off deprecated warnings as errors.
Enable warnings for usage of deprecated functionality, that are meant for the author of the CMakeLists.txt files.
Suppress warnings for usage of deprecated functionality, that are meant for the author of the CMakeLists.txt files.
Make warnings for usage of deprecated macros and functions, that are meant for the author of the CMakeLists.txt files, errors.
Make warnings for usage of deprecated macros and functions, that are meant for the author of the CMakeLists.txt files, not errors.
List CACHE variables will run CMake and list all the variables from the CMake CACHE that are not marked as INTERNAL or ADVANCED. This will effectively display current CMake settings, which can then be changed with -D option. Changing some of the variables may result in more variables being created. If A is specified, then it will display also advanced variables. If H is specified, it will also display help for each variable.
Only load the cache. Do not actually run configure and generate steps.
Generate a graphviz input file that will contain all the library and executable dependencies in the project. See the documentation for CMakeGraphVizOptions for more details.
Dump a wide range of information about the current system. If run from the top of a binary tree for a CMake project it will dump additional information such as the cache, log files etc.
The message() command will only output messages of the specified log level or higher. The default log level is STATUS.
To make a log level persist between CMake runs, set CMAKE_MESSAGE_LOG_LEVEL as a cache variable instead. If both the command line option and the variable are given, the command line option takes precedence.
For backward compatibility reasons, --loglevel is also accepted as a synonym for this option.
This option turns on showing context for the current CMake run only. To make showing the context persistent for all subsequent CMake runs, set CMAKE_MESSAGE_CONTEXT_SHOW as a cache variable instead. When this command line option is given, CMAKE_MESSAGE_CONTEXT_SHOW is ignored.
Do not delete the files and directories created for try_compile() calls. This is useful in debugging failed try_compiles. It may however change the results of the try-compiles as old junk from a previous try-compile may cause a different test to either pass or fail incorrectly. This option is best used for one try-compile at a time, and only when debugging.
Print extra information during the cmake run like stack traces with message(SEND_ERROR) calls.
Print extra find call information during the cmake run to standard error. Output is designed for human consumption and not for parsing. See also the CMAKE_FIND_DEBUG_MODE variable for debugging a more local part of the project.
Print a trace of all calls made and from where.
Like --trace, but with variables expanded.
<format> can be one of the following values.
JSON trace format:
{
"file": "/full/path/to/the/CMake/file.txt",
"line": 0,
"cmd": "add_executable",
"args": ["foo", "bar"],
"time": 1579512535.9687231,
"frame": 2 }
The members are:
Additionally, the first JSON document outputted contains the version key for the current major and minor version of the
JSON trace format:
{
"version": {
"major": 1,
"minor": 0
} }
The members are:
Multiple options are allowed.
Print a warning when an uninitialized variable is used.
Find variables that are declared or set, but not used.
Don’t find variables that are declared on the command line, but not used.
Normally, unused and uninitialized variables are searched for only in CMAKE_SOURCE_DIR and CMAKE_BINARY_DIR. This flag tells CMake to warn about other files as well.
This can aid performance analysis of CMake scripts executed. Third party applications should be used to process the output into human readable format.
Currently supported values are: google-trace Outputs in Google Trace Format, which can be parsed by the about:tracing tab of Google Chrome or using a plugin for a tool like Trace Compass.
CMake provides a command-line signature to build an already-generated project binary tree:
cmake --build <dir> [<options>] [-- <build-tool-options>]
This abstracts a native build tool’s command-line interface with the following options:
The CMAKE_BUILD_PARALLEL_LEVEL environment variable, if set, specifies a default parallel level when this option is not given.
Some native build tools always build in parallel. The use of <jobs> value of 1 can be used to limit to a single job.
This option can be omitted if VERBOSE environment variable or CMAKE_VERBOSE_MAKEFILE cached variable is set.
Run cmake --build with no options for quick help.
CMake provides a command-line signature to install an already-generated project binary tree:
cmake --install <dir> [<options>]
This may be used after building a project to run installation without using the generated build system or the native build tool. The options are:
This option can be omitted if VERBOSE environment variable is set.
Run cmake --install with no options for quick help.
cmake --open <dir>
Open the generated project in the associated application. This is only supported by some generators.
cmake [{-D <var>=<value>}...] -P <cmake-script-file> [-- <unparsed-options>...]
Process the given cmake file as a script written in the CMake language. No configure or generate step is performed and the cache is not modified. If variables are defined using -D, this must be done before the -P argument.
Any options after -- are not parsed by CMake, but they are still included in the set of CMAKE_ARGV<n> variables passed to the script (including the -- itself).
CMake provides builtin command-line tools through the signature
cmake -E <command> [<options>]
Run cmake -E or cmake -E help for a summary of commands. Available commands are:
NOTE:
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4bb7932a29e6f73c97bb9272f2bdc393122f86e0 file1.txt 1df4c8f318665f9a5f2ed38f55adadb7ef9f559c file2.txt
b9b9346bc8437bbda630b0b7ddfc5ea9ca157546dbbf4c613192f930 file1.txt 6dfbe55f4d2edc5fe5c9197bca51ceaaf824e48eba0cc453088aee24 file2.txt
76713b23615d31680afeb0e9efe94d47d3d4229191198bb46d7485f9cb191acc file1.txt 15b682ead6c12dedb1baf91231e1e89cfc7974b3787c1e2e01b986bffadae0ea file2.txt
acc049fedc091a22f5f2ce39a43b9057fd93c910e9afd76a6411a28a8f2b8a12c73d7129e292f94fc0329c309df49434 file1.txt 668ddeb108710d271ee21c0f3acbd6a7517e2b78f9181c6a2ff3b8943af92b0195dcb7cce48aa3e17893173c0a39e23d file2.txt
2a78d7a6c5328cfb1467c63beac8ff21794213901eaadafd48e7800289afbc08e5fb3e86aa31116c945ee3d7bf2a6194489ec6101051083d1108defc8e1dba89 file1.txt 7a0b54896fe5e70cca6dd643ad6f672614b189bf26f8153061c4d219474b05dad08c4e729af9f4b009f1a1a280cb625454bf587c690f4617c27e3aebdf3b7a2d file2.txt
Remove the file(s). The planned behaviour was that if any of the listed files already do not exist, the command returns a non-zero exit code, but no message is logged. The -f option changes the behavior to return a zero exit code (i.e. success) in such situations instead. remove does not follow symlinks. That means it remove only symlinks and not files it point to.
The implementation was buggy and always returned 0. It cannot be fixed without breaking backwards compatibility. Use rm instead.
Remove <dir> directories and their contents. If a directory does not exist it will be silently ignored. If <dir> is a symlink to a directory, just the symlink will be removed. Use rm instead.
The following cmake -E commands are available only on Windows:
CMake provides a pkg-config like helper for Makefile-based projects:
cmake --find-package [<options>]
It searches a package using find_package() and prints the resulting flags to stdout. This can be used instead of pkg-config to find installed libraries in plain Makefile-based projects or in autoconf-based projects (via share/aclocal/cmake.m4).
NOTE:
To print selected pages from the CMake documentation, use
cmake --help[-<topic>]
with one of the following options:
Usage describes the basic command line interface and its options.
If a file is specified, the version is written into it. The help is printed to a named <f>ile if given.
All manuals are printed in a human-readable text format. The help is printed to a named <f>ile if given.
The specified manual is printed in a human-readable text format. The help is printed to a named <f>ile if given.
The list contains all manuals for which help may be obtained by using the --help-manual option followed by a manual name. The help is printed to a named <f>ile if given.
The cmake-commands(7) manual entry for <cmd> is printed in a human-readable text format. The help is printed to a named <f>ile if given.
The list contains all commands for which help may be obtained by using the --help-command option followed by a command name. The help is printed to a named <f>ile if given.
The cmake-commands(7) manual is printed in a human-readable text format. The help is printed to a named <f>ile if given.
The cmake-modules(7) manual entry for <mod> is printed in a human-readable text format. The help is printed to a named <f>ile if given.
The list contains all modules for which help may be obtained by using the --help-module option followed by a module name. The help is printed to a named <f>ile if given.
The cmake-modules(7) manual is printed in a human-readable text format. The help is printed to a named <f>ile if given.
The cmake-policies(7) manual entry for <cmp> is printed in a human-readable text format. The help is printed to a named <f>ile if given.
The list contains all policies for which help may be obtained by using the --help-policy option followed by a policy name. The help is printed to a named <f>ile if given.
The cmake-policies(7) manual is printed in a human-readable text format. The help is printed to a named <f>ile if given.
The cmake-properties(7) manual entries for <prop> are printed in a human-readable text format. The help is printed to a named <f>ile if given.
The list contains all properties for which help may be obtained by using the --help-property option followed by a property name. The help is printed to a named <f>ile if given.
The cmake-properties(7) manual is printed in a human-readable text format. The help is printed to a named <f>ile if given.
The cmake-variables(7) manual entry for <var> is printed in a human-readable text format. The help is printed to a named <f>ile if given.
The list contains all variables for which help may be obtained by using the --help-variable option followed by a variable name. The help is printed to a named <f>ile if given.
The cmake-variables(7) manual is printed in a human-readable text format. The help is printed to a named <f>ile if given.
The following resources are available to get help using CMake:
The primary starting point for learning about CMake.
Links to available documentation and community resources may be found on this web page.
The Discourse Forum hosts discussion and questions about CMake.
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September 13, 2021 | 3.18.4 |