protoc.cmake:
set(protoc_files
${protobuf_source_dir}/src/google/protobuf/compiler/main.cc
)
add_executable(protoc ${protoc_files})
target_link_libraries(protoc libprotobuf libprotoc)
add_executable(protobuf::protoc ALIAS protoc)
set(PROTOC_NAME "protoc")
set_target_properties(protoc PROPERTIES
VERSION ${protobuf_VERSION}
OUTPUT_NAME ${PROTOC_NAME})
if(WIN32)
set(PROTOC_SUFFIX ".exe")
set_target_properties(protoc PROPERTIES
SUFFIX ${PROTOC_SUFFIX})
else()
set(PROTOC_SUFFIX)
endif()
set(PROTOBUF_PROTOC_EXECUTABLE "${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/${PROTOC_NAME}${PROTOC_SUFFIX}" PARENT_SCOPE)
I have included source of google protocol buffer compiler to my project, and I use previous cmake file for generating runtime binary, but instead of one file I get two executable files: "protoc" and "protoc-3.6.1".
I am using CLion IDE 2018.1.5 with bundled CMake 3.10.3 on Ubuntu 18.04.
On Windows I don't have a such problem.
As #Tsyvarev said in comment, one of these files is actually a symlink to another one. This is what VERSION property implies.
Related
I've been stuck for a while now and I can't figure out how to get freeglut working. I thought I knew what it was asking me to do, so I added that set(prefix_path) line but it didn't do anything. Am I supposed to write my own freeglut-config.cmake or what?
Note: I am using the freeglut for MinGW package from this website
CMake File:
cmake_minimum_required(VERSION 3.7)
project(HW1)
set(CMAKE_CXX_STANDARD 11)
set(SOURCE_FILES Triangle.cpp)
set(CMAKE_PREFIX_PATH "C:/freeglut")
find_package(GLEW REQUIRED STATIC)
find_package(FREEGLUT REQUIRED)
find_package(OPENGL REQUIRED)
include_directories(${FREEGLUT_INCLUDE_DIRS} ${GLEW_INCLUDE_DIRS} ${OPENGL_INCLUDE_DIRS})
link_directories(${FREEGLUT_LIBRARY_DIRS} ${GLEW_LIBRARY_DIRS} ${OPENGL_LIBRARY_DIRS})
add_definitions(${FREEGLUT_DEFINITIONS} ${GLEW_DEFINITIONS} ${OPENGL_DEFINITIONS})
add_executable(HW1 ${SOURCE_FILES})
target_link_libraries(HW1 ${FREEGLUT_LIBRARIES} ${GLEW_LIBRARIES} ${OPENGL_LIBRARIES})
Full error:
CMake Error at CMakeLists.txt:8 (find_package):
By not providing "FindFREEGLUT.cmake" in CMAKE_MODULE_PATH this project has
asked CMake to find a package configuration file provided by "FREEGLUT",
but CMake did not find one.
Could not find a package configuration file provided by "FREEGLUT" with any
of the following names:
FREEGLUTConfig.cmake
freeglut-config.cmake
Add the installation prefix of "FREEGLUT" to CMAKE_PREFIX_PATH or set
"FREEGLUT_DIR" to a directory containing one of the above files. If
"FREEGLUT" provides a separate development package or SDK, be sure it has
been installed.
If your application is GLUT-compatible, that it doesn't use any extension of freeglut, then it is better to search GLUT instead of FREEGLUT:
find_package(GLUT REQUIRED)
"Find" script used by this command is already shipped into CMake distro, and it searches freeglut too.
(Note, that with that command variables for include directories and linking libraries are GLUT_INCLUDE_DIR and GLUT_LIBRARY correspondingly).
If your application requires exactly freeglut (that is, uses some of its extensions incompatible with other GLUT implementations), you need to ship your package with FindFREEGLUT.cmake script and adjust CMAKE_MODULE_PATH variable correspondingly:
# Assuming you have <source-dir>/cmake/FindFREEGLUT.cmake
list(APPEND CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/cmake")
find_package(FREEGLUT REQUIRED)
You may find existing script in the net, or write it by yourself, like here.
In any case, if you have freeglut installed into non-system location, you need to hint CMake about that. E.g., by adjusting CMAKE_PREFIX_PATH.
I'm on cmake version 3.12.1 and want to build a static executable that uses ZLIB. I have both the static (libz.a) and shared (libz.so) libraries on my machine. How can I tell find_package(ZLIB) to return the static version? Maybe there's another way to find libz.a as well?
My present workaround is to specify:
SET(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -static")
Then:
target_link_libraries (my_binary z lib1 lib2)
Critique on this approach is also welcome!
As of CMake 3.24, use: set(ZLIB_USE_STATIC_LIBS "ON")
Source
Your approach is valid given the limitations of the CMake module called by find_package(ZLIB), specifically FindZLIB.cmake. While other FindXXX.cmake modules have a special option for grabbing static libraries, the zlib module does not.
There are already a few questions on SO about this topic, but some are older than others, so there are a few options.
You can instead apply the -static flag on a more granular level (rather than editing the global CMAKE_EXE_LINKER_FLAGS variable) by adding it to your target_link_libraries call. This way it will apply only to that target -- useful if you are building other non-static targets.
You could also tell CMake to search for static libraries explicitly by setting CMAKE_FIND_LIBRARY_SUFFIXES. When find_package is called, CMake can search for libraries ending in .a using this:
SET(CMAKE_FIND_LIBRARY_SUFFIXES ".a")
find_package(ZLIB REQUIRED)
If you have control over installing zlib, for example, you are installing dependencies in a Continuous Integration setup, I would recommend to just remove the zlib dynamic library.
zlib doesn't have the option to build statically or dynamically, it automatically generates both versions. However FindZlib.cmake prioritizes the dynamic version.
I find the following approach to be better in case you don't have access to modify third parties repositories CMakeLists.txt that needs zlib:
if (CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
set(_compiler_is_msvc ON)
endif()
option(ZLIB_FORCE_STATIC "Remove the dynamic libraries after zlib install" ON)
mark_as_advanced(ZLIB_FORCE_STATIC)
set(OUTPUT_BUILD_DIR ${CMAKE_CURRENT_BINARY_DIR} CACHE PATH "Base folder where builds and source folder will be installed: i.e. OUTPUT_BUILD_DIR/zlib")
if(_compiler_is_msvc)
set(ZLIB_GIT_TAG cacf7f1d4e3d44d871b605da3b647f07d718623f) # Version 1.2.11
message(STATUS "ZLIB_VERSION: ${ZLIB_GIT_TAG} : Version 1.2.11")
set(ZLIB_BUILD_DIR ${OUTPUT_BUILD_DIR}/zlib-build)
set(ZLIB_INSTALL_DIR ${OUTPUT_BUILD_DIR}/zlib)
set(ZLIB_SRC_FOLDER_NAME zlib-src)
set(ZLIB_SRC_DIR ${OUTPUT_BUILD_DIR}/${ZLIB_SRC_FOLDER_NAME})
set(ZLIB_GIT_REPOSITORY "https://github.com/madler/zlib")
ExternalProject_Add(ep_zlib
GIT_REPOSITORY ${ZLIB_GIT_REPOSITORY}
GIT_TAG ${ZLIB_GIT_TAG}
# GIT_SHALLOW TRUE
GIT_PROGRESS TRUE
CMAKE_GENERATOR ${CMAKE_GENERATOR}
SOURCE_DIR ${ZLIB_SRC_DIR}
BINARY_DIR ${ZLIB_BUILD_DIR}
CMAKE_ARGS
-DCMAKE_C_COMPILER:FILEPATH=${CMAKE_C_COMPILER}
-DCMAKE_CXX_COMPILER:FILEPATH=${CMAKE_CXX_COMPILER}
-DCMAKE_BUILD_TYPE:STRING=${SGEXT_CMAKE_BUILD_TYPE}
-DBUILD_SHARED_LIBS:BOOL=OFF
-DCMAKE_INSTALL_PREFIX=${ZLIB_INSTALL_DIR}
)
if(ZLIB_FORCE_STATIC)
ExternalProject_Add_Step(
ep_zlib zlib_remove_dll
COMMENT "Remove zlib.lib and zlib.dll, leaves only zlibstatic.lib"
DEPENDEES install
COMMAND ${CMAKE_COMMAND} -E remove -f ${ZLIB_INSTALL_DIR}/lib/zlib.lib ${ZLIB_INSTALL_DIR}/bin/zlib.dll
)
endif()
endif()
The last step removes the dynamic version, so the default FindZLIB will find the static library.
The best solution I found was to name the library explicitly when calling CMake:
cmake -DZLIB_LIBRARY=/usr/lib/x86_64-linux-gnu/libz.a /path/to/source
I would not recommend the solution proposed by #phcerdan because in my case the installed shared library was colliding with an already installed version, so the only solution was to make sure it never gets installed in the first place. The key idea is to disable completely the targets installation using SKIP_INSTALL_LIBRARIES, and instead to "install" the static library manually. Nonetheless, my solution is quite similar:
EXTERNALPROJECT_ADD(zlib_external
GIT_REPOSITORY https://github.com/madler/zlib.git
GIT_TAG v1.2.11
CMAKE_ARGS
-DSKIP_INSTALL_FILES=ON # Disable install of manual and pkgconfig files
-DSKIP_INSTALL_LIBRARIES=ON # Do not install libraries automatically. It will be handled manually to avoid installing shared libs
-DBUILD_SHARED_LIBS=OFF
-DCMAKE_TOOLCHAIN_FILE=${CMAKE_TOOLCHAIN_FILE}
-DCMAKE_INSTALL_PREFIX:PATH=${CMAKE_INSTALL_PREFIX}
-DCMAKE_C_FLAGS:STRING=${CMAKE_COMPILE_FLAGS_EXTERNAL}
${EXTERNALPROJECT_BUILD_TYPE_CMD}
INSTALL_DIR ${CMAKE_INSTALL_PREFIX}
)
if(NOT WIN32)
set(zlib_BUILD_LIB_PATH "<BINARY_DIR>/libz.a")
set(zlib_PATH "${CMAKE_INSTALL_PREFIX}/lib/libz.a")
else()
set(zlib_BUILD_LIB_PATH "<BINARY_DIR>/Release/zlibstatic.lib")
set(zlib_PATH "${CMAKE_INSTALL_PREFIX}/lib/zlibstatic.lib")
endif()
ExternalProject_Add_Step(
zlib_external zlib_install_static_only
COMMENT "Manually installing only static library"
DEPENDEES install
COMMAND ${CMAKE_COMMAND} -E copy ${zlib_BUILD_LIB_PATH} ${zlib_PATH}
)
I have troubles finding out the right "library target name" to be used in a cmake file, for packages installed using vcpkg.
In example, I installed the gtest package using vcpkg install gtest. My sample cmake file looks like:
#CMakeLists.txt
cmake_minimum_required(VERSION 3.0)
project(example)
add_executable(main main.cpp)
find_package(gtest REQUIRED)
target_link_libraries(main gtest) # here, "gtest" is not the right name!
Running cmake, a solution for Visual Studio is generated, but after running cmake --build ., I get the error:
../use-cmake-vcpkg\main.cpp(1): fatal error C1083: Cannot open include file: 'gtest/gtest.h': No such file or directory ..
Turns out the line: target_link_libraries(main gtest) isn't correct, and I need to use another "name" to include/link the gtest package.
Is there a way (using cmake or vcpkg) to find out what is the correct target name to be used? (for gtest in this case, but also for any other pacakage?)
When use find_package(XXX), it can work in two modes: MODULE and CONFIG. And resulted variables and targets of this call depend on the mode.
If FindXXX.cmake file exists (and can be found), the MODULE mode is used and given file is processed. Otherwise, if the package is shipped with XXXConfig.cmake file, CONFIG mode is used and given file is processed. If none of this file exists, CMake emits an error (if called with REQUIRED keyword) or a warning (without REQUIRED keyword).
In case of gtest package, CMake is shipped with FindXXX.cmake script, so this script is processed in MODULE mode. You may find description of this script in the documentation, which tells that you need to use GTest::GTest target for link with gtest:
target_link_libraries(main GTest::GTest)
Not all packages provide a CMake library definition. If you're lucky, then vcpkg install will show you the name:
$ ./vcpkg install openssl
The package openssl is compatible with built-in CMake targets:
find_package(OpenSSL REQUIRED)
target_link_libraries(main PRIVATE OpenSSL::SSL OpenSSL::Crypto)
This will work even if you've already installed the package, so you can use it anytime to query the package name.
On the other hand, if vcpkg install <pkg> doesn't say anything about CMake, then you need to include it manually in your CMake file, by finding the include path and the library files.
Here is an example of such a case, here for the live555 library:
# Use one of the headers to locate the include location
find_path(LIVE555_INCLUDE_DIR liveMedia.hh)
# Find the libraries
find_library(LIVE555_LIBRARY1 liveMedia)
find_library(LIVE555_LIBRARY2 groupsock)
find_library(LIVE555_LIBRARY3 BasicUsageEnvironment)
find_library(LIVE555_LIBRARY4 UsageEnvironment)
add_executable(rtsp testRTSPClient.cpp)
target_include_directories(rtsp PRIVATE ${LIVE555_INCLUDE_DIR})
target_link_libraries(rtsp PRIVATE ${LIVE555_LIBRARY1} ${LIVE555_LIBRARY2} ${LIVE555_LIBRARY3} ${LIVE555_LIBRARY4})
I'm trying to make a project that has both ZLIB and LIBPNG (and other libraries). LibPNG's CMakeLists.txt file has this in it: find_package(ZLIB REQUIRED) It's stock code that comes with it and I don't want to change it.
I'm building on Windows (Visual Studio). This is a cross-platform application (Windows, Mac, Linux and Mobile devices) I cannot rely on /usr/lib versions of any libraries. So I'm building them all with my project together.
I can't get LibPNG to build unless I hack this up. In an upper-level CMakeLists.txt file, I put this in there:
ADD_SUBDIRECTORY(contrib/${CUSTOM_ZLIB_LOCATION})
SET(ZLIB_FOUND ON CACHE BOOL "Yes")
SET(ZLIB_INCLUDE_DIR ${CMAKE_BINARY_DIR}/contrib/${CUSTOM_ZLIB_LOCATION} {CMAKE_SOURCE_DIR}/contrib/${CUSTOM_ZLIB_LOCATION})
SET(ZLIB_LIBRARY zlib CACHE STRING "zlib library name")
This satisfies find_package(ZLIB REQUIRED) But I think this is a hack. Is there some straight forward way to build the local copy of zlib without all the 3 extra lines?
I only added this line at the beginning (at least before find_package(ZLIB REQUIRED)) and it worked for me.
set(ZLIB_ROOT <zlib folder here>)
But others may need doing something like:
if (CMAKE_VERSION VERSION_GREATER 3.12 OR CMAKE_VERSION VERSION_EQUAL 3.12)
# Enable find_package uses of <PackageName>_ROOT variables.
cmake_policy(SET CMP0074 NEW)
endif()
set(ZLIB_ROOT <zlib folder here>)
We set the policy to NEW.
The OLD behavior for this policy is to ignore <PackageName>_ROOT variables.
CMake version 3.22.1 warns when the policy is not set (and defaults to OLD behavior).
CMake cannot find my Eigen3 package. I set an environment variable called
EIGEN3_INCLUDE_DIR
pointing to the path where FindEigen3.cmake is.
Then in the CMakelists.txt I wrote:
find_package( Eigen3 REQUIRED )
include_directories( EIGEN3_INCLUDE_DIR )
I get next message of error:
CMake Error at C:/Program Files (x86)/CMake 2.8/share/cmake-2.8/Modules/FindPackageHandleStandardArgs.cmake:91 (MESSAGE):
Could NOT find Eigen3 (missing: EIGEN3_INCLUDE_DIR EIGEN3_VERSION_OK)
(Required is at least version "2.91.0")
Call Stack (most recent call first):
C:/Program Files (x86)/CMake 2.8/share/cmake-2.8/Modules/FindPackageHandleStandardArgs.cmake:252 (_FPHSA_FAILURE_MESSAGE)
C:/Program Files (x86)/CMake 2.8/share/cmake-2.8/Modules/FindEigen3.cmake:76 (find_package_handle_standard_args)
test/test_quaternion/CMakeLists.txt:25 (find_package)
Any idea on what I am missing or doing wrong?
Since Eigen3 is completely header only, all you ever need is the path to the include directory. And this one, you are already defining manually anyway. So there is no real need for a FindEigen3.cmake or FIND_PACKAGE call.
Simply use
INCLUDE_DIRECTORIES ( "$ENV{EIGEN3_INCLUDE_DIR}" )
or
SET( EIGEN3_INCLUDE_DIR "$ENV{EIGEN3_INCLUDE_DIR}" )
IF( NOT EIGEN3_INCLUDE_DIR )
MESSAGE( FATAL_ERROR "Please point the environment variable EIGEN3_INCLUDE_DIR to the include directory of your Eigen3 installation.")
ENDIF()
INCLUDE_DIRECTORIES ( "${EIGEN3_INCLUDE_DIR}" )
A few notes:
If you want to access the content of a CMake variable, make sure to use ${...}
$ENV{....} accesses environment variables.
The second example will stop with an error if the environment variable is not set (and, thus, EIGEN3_INCLUDE_DIR cmake variable is empty)
Be careful to use quotation marks around (evaluated) variables if they could contain whitespace. Otherwise, CMake will interpret it as a list.
If you want to use custom find modules, make sure to either place them in you CMake installation or, as #Fraser pointed out above, make sure to point CMAKE_MODULE_PATH to the directory where it is. Not sure, but it could be that CMake checks the current directory as well automatically (where your CMakeLists.txt resides. Anyhow, setting EIGEN3_INCLUDE_DIR is totally unrelated to the location of FindEigen3.cmake
However, it could be that your FindEigen3 script evaluates this variable to determine the location of your Eigen3 installation.
Alternatively, self-built CMake-based projects often provide a <PackageName>Config.cmake. If you point a variable called <PackageName>_DIR to the directory containing this file, you can use FIND_PACKAGE( <PackageName> ...) as normal. See documentation of FIND_PACKAGE for details.
Eigen >= 3.3 has direct CMake integration, so it seems yours isn't set up correctly.
Assume Eigen has been installed to /opt/eigen/3.3 with default settings. Append or prepend the the location /opt/eigen/3.3 to the environment variable CMAKE_PREFIX_PATH e.g in bash:
export CMAKE_PREFIX_PATH="$CMAKE_PREFIX_PATH:/opt/eigen/3.3"
Then CMake should pick it up.
If you are writing your own CMakeLists.txt that uses Eigen I suggest using code like this:
find_package (Eigen3 3.3 REQUIRED)
add_executable (example example.cpp)
target_link_libraries (example Eigen3::Eigen)
You should not use include_directories since CMake 3 was released -- the targets approach should be preferred whenever available.
First, make sure Eigen is properly installed. Refer to the INSTALL file that comes with the tarball.
Second, copy the cmake/FindEigen3.cmake file from the tarball to the directory containing your CMakeLists.txt.
In your CMakeLists.txt add:
set(CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR})
find_package(Eigen3 REQUIRED)
include_directories(${EIGEN3_INCLUDE_DIR})
Now you should be able to do e.g. #include <Eigen/Core>.
All of this comes (mostly) from this source.
This approach has the advantage over e.g. include_directories("$ENV{EIGEN3_INCLUDE_DIR}") that it the uses CMake's standard mechanism for finding external dependencies, making it easier for someone else (or your future self) to pick up the project, possibly on another platform.
(However, it would be nice if Eigen itself installed an EigenConfig.cmake file, making it accessible through the find_package mechanism without any extra paths.)
I found another solution here (which referred to here) which uses the pkg-config file :
find_package(PkgConfig)
pkg_search_module(Eigen3 REQUIRED eigen3)
As a detailed explanation of the note 7 from the top answer of Johannes. By using the "Config mode" rather than "Module mode" of CMake find_packate(), only writing
find_package( Eigen3 REQUIRED )
include_directories( EIGEN3_INCLUDE_DIR )
in CMakeLists.txt is enough.
Please refer to the INSTALL guidance text file contained in the eigen source code directory (eg. extracted from eigen-3.3.7.tar.gz downloaded from official website), which said:
Method 2. Installing using CMake
********************************
Let's call this directory 'source_dir' (where this INSTALL file is).
Before starting, create another directory which we will call 'build_dir'.
Do:
cd build_dir
cmake source_dir
make install
The "make install" step may require administrator privileges.
You can adjust the installation destination (the "prefix")
by passing the -DCMAKE_INSTALL_PREFIX=myprefix option to cmake, as is
explained in the message that cmake prints at the end.
Just like installing usual CMake projects to your machine.
The difference from directly including the /usr/include/eigne3 or /usr/local/include/eigen3 directory is that, a configuration directory called eigen3/cmake will also be installed to /usr/share or usr/local/share. This configuration directory contains the Eigen3Config.cmake file, which can automatically be found by CMake to locate the eigen3 directory.
If you have not added Eigen Library to environment variable then do the following in CMakeLists.txt:
cmake_minimum_required(VERSION 3.9)
project(ProjectName)
set(CMAKE_CXX_STANDARD 11)
# set EIGEN_DIR variable to Eigen Library Path
set(EIGEN_DIR "C:\\Eigendir\\Eigen")
# include the directory
include_directories(${EIGEN_DIR})
add_executable(ProjectName main.cpp)
target_link_libraries(ProjectName ${EIGEN_DIR})
Another simple way that doesn't require adding an environment variable is to simply find eigen with the cmake find_path function https://cmake.org/cmake/help/v3.6/command/find_path.html. The example code finds the directory "Eigen" in paths "/usr/include/" and "/usr/local/include" with an additional search in subdirectory "eigen3".
find_path(EIGEN3_INCLUDE_DIRS "Eigen" paths "/usr/include" "/usr/local/include" path_suffixes "eigen3")
message(${EIGEN3_INCLUDE_DIRS})
if ( NOT EIGEN3_INCLUDE_DIRS )
message(FATAL_ERROR "CMake variable EIGEN3_INCLUDE_DIRS not found.")
endif()
include_directories ( "${EIGEN3_INCLUDE_DIRS}" )
You could try setting the CMAKE_MODULE_PATH to the location of Eigen subdirectory named "cmake":
cmake . -DCMAKE_MODULE_PATH=<Eigen root dir>/cmake/
I had a similar problem when run cmake .. && make on Google Colab on a project clone from github. I fixed it by editing CMakeLists.txt file and adding this line to it:
set(EIGEN3_INCLUDE_DIR "/usr/include/eigen3")
As you can see, my eigen3 was in /usr/include/eigen3 path (and I had installed it using !sudo apt-get install build-essential cmake libeigen3-dev)
When installing on Kubuntu 20.04 following steps from INSTALL:
Do:
cd build_dir
cmake source_dir
make install
using -DCMAKE_INSTALL_PREFIX=/usr/local/eigen-3.4.0 and sudo
FindEigen3.cmake is not installed. However, using
set(Eigen3_DIR "/usr/local/eigen/share/eigen3/cmake")
seem to work. FindEigen3.cmake is in the build directory
but it is not copied to the installation directory tree.
This worked:
Changed c++11 to c++14
Changed find_package(Eigen3 QUIET) to find_package(Eigen3 CONFIG)
Another simple way is:
if the Eigen library is in /opt/eigen/3.3/Eigen
include_directories(/opt/eigen/3.3)
which is equivalent to what Jai suggested
set(EIGEN_DIR "/opt/eigen/3.3")
include_directories(${EIGEN_DIR})
You need to read official documentation:
Click here
After install Eigen from tar and compile it correctly.
CMakeLists.txt will looks like this:
find_package(Eigen3 3.3 REQUIRED NO_MODULE)
add_executable(${PROJECT_NAME} something.cpp)
target_link_libraries(${PROJECT_NAME} Eigen3::Eigen)
It will be fine work.