CODEWITHSUNDEEP
cmake
Michael
Michael

Reputation: 3844

CMake: Print out all accessible variables in a script

I'm wondering if there is a way to print out all accessible variables in CMake. I'm not interested in the CMake variables - as in the --help-variables option. I'm talking about my variables that I defined, or the variables defined by included scripts.

I'm currently including:

INCLUDE (${CMAKE_ROOT}/Modules/CMakeBackwardCompatibilityCXX.cmake)

And I was hoping that I could just print out all the variables that are here, instead of having to go through all the files and read what was available - I may find some variables I didn't know about that may be useful. It would be good to aid learning & discovery. It is strictly for debugging/development.

This is similar to the question in Print all local variables accessible to the current scope in Lua, but for CMake!

Has anyone done this?

Upvotes: 321

Views: 240663

Answers (8)

w.t
w.t

Reputation: 497

For env vars:

message(STATUS "$ENV{BLABLA}")

Upvotes: 0

sakra
sakra

Reputation: 65971

Using the get_cmake_property function, the following loop will print out all CMake variables defined and their values:

get_cmake_property(_variableNames VARIABLES)
list (SORT _variableNames)
foreach (_variableName ${_variableNames})
    message(STATUS "${_variableName}=${${_variableName}}")
endforeach()

This can also be embedded in a convenience function which can optionally use a regular expression to print only a subset of variables with matching names

function(dump_cmake_variables)
    get_cmake_property(_variableNames VARIABLES)
    list (SORT _variableNames)
    foreach (_variableName ${_variableNames})
        if (ARGV0)
            unset(MATCHED)
            string(REGEX MATCH ${ARGV0} MATCHED ${_variableName})
            if (NOT MATCHED)
                continue()
            endif()
        endif()
        message(STATUS "${_variableName}=${${_variableName}}")
    endforeach()
endfunction()

Or, in a more compact form:

function(dump_cmake_variables)
    get_cmake_property(_variableNames VARIABLES)
    list (SORT _variableNames)
    foreach (_variableName ${_variableNames})
        if ((NOT DEFINED ARGV0) OR _variableName MATCHES ${ARGV0})
            message(STATUS "${_variableName}=${${_variableName}}")
        endif()
    endforeach()
endfunction()

To print environment variables, use CMake's command mode:

execute_process(COMMAND "${CMAKE_COMMAND}" "-E" "environment")

Upvotes: 582

bukzor
bukzor

Reputation: 38532

None of the current answers allowed me to see the variables in my project subdirectory. Here's a solution:

function(print_directory_variables dir)
    # Dump variables:
    get_property(_variableNames DIRECTORY ${dir} PROPERTY VARIABLES)
    list (SORT _variableNames)
    foreach (_variableName ${_variableNames})
        get_directory_property(_variableValue DIRECTORY ${dir} DEFINITION ${_variableName})
        message(STATUS "DIR ${dir}: ${_variableName}=${_variableValue}")
    endforeach()
endfunction(print_directory_variables)

# for example
print_directory_variables(.)
print_directory_variables(ui/qt)

Upvotes: 1

Furlings
Furlings

Reputation: 113

You can use message :

message([STATUS] "SUB_SOURCES : ${SUB_SOURCES}")

Upvotes: 1

Willem Hengeveld
Willem Hengeveld

Reputation: 2776

Another way to view all cmake's internal variables, is by executing cmake with the --trace-expand option.

This will give you a trace of all .cmake files executed and variables set on each line.

Upvotes: 5

Shimon Doodkin
Shimon Doodkin

Reputation: 4579

based on @sakra

function(dump_cmake_variables)
    get_cmake_property(_variableNames VARIABLES)
    list (SORT _variableNames)
    foreach (_variableName ${_variableNames})
        if (ARGV0)
            unset(MATCHED)

            #case sensitive match
            # string(REGEX MATCH ${ARGV0} MATCHED ${_variableName})
            #
            #case insenstitive match
            string( TOLOWER "${ARGV0}" ARGV0_lower )
            string( TOLOWER "${_variableName}" _variableName_lower )
            string(REGEX MATCH ${ARGV0_lower} MATCHED ${_variableName_lower})

            if (NOT MATCHED)
                continue()
            endif()
        endif()
        message(STATUS "${_variableName}=${${_variableName}}")
    endforeach()
endfunction()

dump_cmake_variables("^Boost")

variable names are case sensitive

btw if you are interested in boost, it is Boost_INCLUDE_DIRS not BOOST_INCLUDE_DIRS, and it is Boost_LIBRARIES not BOOST_LIBRARIES, and by mistake I had BOOST_LIBRARIES instead of Boost_LIBRARIES, https://cmake.org/cmake/help/v3.0/module/FindBoost.html , better example for boost:

set(Boost_USE_STATIC_LIBS ON)
find_package(Boost REQUIRED COMPONENTS RANDOM)
include_directories(${Boost_INCLUDE_DIRS})

target_link_libraries(myfile PRIVATE
 ${Boost_LIBRARIES}
)

Upvotes: 4

jtsagata
jtsagata

Reputation: 2383

Another way is to simply use:

cmake -LAH

From the manpage:

-L[A][H]

List non-advanced cached variables.

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 [...].

If A is specified, then it will display also advanced variables.

If H is specified, it will also display help for each variable.

Upvotes: 213

Ciro Santilli OurBigBook.com
Ciro Santilli OurBigBook.com

Reputation: 384144

ccmake is a good interactive option to interactively inspect cached variables (option( or set( CACHE:

sudo apt-get install cmake-curses-gui
mkdir build
cd build
cmake ..
ccmake ..

Upvotes: 13

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