CMake have special variable ${QT_DEFINITIONS} for Qt4 which contains qt defines such as QT_NO_DEBUG and QT_DEBUG. There is no such option for Qt5.
How can I add standard Qt5 defines in cmake?
Please check <component>_DEFINITIONS / <component>_COMPILE_DEFINITIONS.
There's an example using Qt Widgets and CMake here. The two essential parts:
# Find the QtWidgets library
find_package(Qt5Widgets)
# Add the include directories for the Qt 5 Widgets module to
# the compile lines.
include_directories(${Qt5Widgets_INCLUDE_DIRS})
Calling find_package() will set those variables for you:
Qt5Widgets_VERSION_STRING
Qt5Widgets_LIBRARIES List of libraries for use with the target_link_libraries command, for example.
Qt5Widgets_INCLUDE_DIRS List of libraries for use with the include_directories command, for example.
Qt5Widgets_DEFINITIONS List of definitions for use with add_definitions, for example.
Qt5Widgets_COMPILE_DEFINITIONS List of definitions for use with the COMPILE_DEFINITIONS target property.
Qt5Widgets_FOUND Boolean describing whether the module was found successfully.
Qt5Widgets_EXECUTABLE_COMPILE_FLAGS String of flags to be used when building executables.
(Quoted from link above; the name depends on what you search in your find_package() call)
Related
I'm new(ish) to CMake (meaning off and on over a few years I've been forced to use it even though it's something that's made me question my career path).
I have a folder with an include folder, and a lib folder containing .lib files and their corresponding .dlls for a dependency I'll call "mydep". I need to provide the infrastructure files, mydep-config.cmake, mydep-target.cmake, etc, which will add the includes folders and .lib files to the command line for compiling and linking and then move the .dlls to a specific location.
Can anyone point me to a simple example anywhere on the net that illustrates the way to do this? The CMake documentation is utterly useless.
Thanks!
There are basically 2 files you need to put in the correct location on the file system. Let's assume the library is to import is called ExternLib with version 1.2.3 and compiled for 64 bit. With the and you've got it stored in your repo as
external_dependencies/lib/ExternLib.lib
external_dependencies/bin/ExternLib.dll
external_dependencies/include/ExternLib/ExternHeader.hpp
external_dependencies/include/ExternLib/...
...
and you want the include paths used in your project to be
#include "ExternLib/ExternHeader.hpp"
First of all we'll use the file names externlib-config.cmake and externlib-version-config.cmake to allow the user to use arbitrary case when using find_package.
externlib-version-config.cmake
This file is used to check, if the version of the config script is compatible with the cmake configuration trying to find the package. Adding this file allows you to place multiple versions of the library to be found for different target architectures (e.g. Windows x64, Win32, linux x86_64, ...). find_package won't read the externlib-config.cmake in the same directory, if the version is marked as non-compatible via the version file.
set(PACKAGE_VERSION "1.2.3")
# basically ignore the version passed
set(PACKAGE_VERSION_COMPATIBLE TRUE) # consider every version compatible
#usually you'd add logic for ignoring any unspecified parts of the version here instead of treating unspecified version parts as 0
# we'll keep it simple though
if(PACKAGE_FIND_VERSION VERSION_EQUAL PACKAGE_VERSION)
set(PACKAGE_VERSION_EXACT TRUE) # make version as exact match
endif()
if(NOT WIN32)
set(PACKAGE_VERSION_COMPATIBLE FALSE) # disallow older version
else()
if (NOT CMAKE_SYSTEM_NAME STREQUAL "Windows") # note: we'll ignore the possibility of find_package before the first project() command
set(PACKAGE_VERSION_UNSUITABLE TRUE)
endif()
if(NOT CMAKE_SIZEOF_VOID_P STREQUAL "8") # check for 64 bit
set(PACKAGE_VERSION_UNSUITABLE TRUE)
endif()
externlib-config.cmake
Here we'll put the creation of the actual library in addition to providing any functions/macros/variables the user should have access to. We'll use ExternLib::ExternLib as target name, but you can simply replace this by any name of your choosing unique in your project.
if(NOT TARGET ExternLib::ExternLib) # prevent recreation on multiple uses of find_package
add_library(ExternLib::ExternLib SHARED IMPORTED)
get_filename_component(EXTERNLIB_BASE_DIR ${CMAKE_CURRENT_LISTS_DIR}/../../.. ABSOLUTE)
set(EXTERNLIB_BINARY_DIR ${EXTERNLIB_BASE_DIR} CACHE INTERNAL "Directory containing the dlls for ExternLib")
# add info about locations of the dll/lib files
set_target_properties(ExternLib::ExternLib PROPERTIES
IMPORTED_LOCATION "$CACHE{EXTERNLIB_BINARY_DIR}/ExternLib.dll"
IMPORTED_IMPLIB "${EXTERNLIB_BASE_DIR}/lib/ExternLib.lib"
)
# add include directory information
target_include_directories(ExternLib::ExternLib INTERFACE "${EXTERNLIB_BASE_DIR}/include")
# add dependencies, if required; you may need to use find_package to locate those
# target_link_libraries(ExternLib::ExternLib INTERFACE ...)
endif()
# any helper function/macro definitions should go here, since they may need to get reintroduced
Note: I did ignore the possibility of components of a package being specified here. Any components specifying components for find_package are simply ignored for the script above.
Placement of the files
You'll need to place the files in one of some possible paths below one of the directories mentioned in CMAKE_PREFIX_PATH or in one of the default dirs, see find_package Config Mode Search Procedure.
Note: we'll use a path that isn't documented for windows, since this path would also work for linux. (Boost is doing this too.)
lib/cmake/ExternLib-x64-1.2.3
(You could choose a different suffix to lib/cmake/ExternLib or just use lib/cmake/ExternLib. The search procedure picks up on any directory names which starts with the package name ignoring case, if it expects the lib name.)
Place both the files in this directory. externlib-config.cmake assumes lib is external_dependencies/lib here. Otherwise you may need to adjust EXTERNLIB_BASE_DIR accordingly.
Usage
We'll assume the CMakeLists.txt file is placed in the same directory as external_dependencies
project(...)
...
add_executable(my_exe ...)
...
# this allows the user to pass directories to be searched first via -D option during configuration
list(APPEND CMAKE_PREFIX_PATH ${CMAKE_CURRENT_SOURCE_DIR}/external_dependencies)
find_package(ExternLib REQUIRED)
target_link_libraries(my_exe PRIVATE ExternLib::ExternLib)
# allow vs debugger to find the dll without copying the dlls around
set_target_properties(my_exe PROPERTIES
VS_DEBUGGER_ENVIRONMENT "PATH=${EXTERNLIB_BINARY_DIR};$ENV{PATH}"
)
I want to iterate over all link libraries of a target target to build a list of all library binaries (static libraries) which target links to, e.g.
add_executable(exe main.cpp)
target_link_libraries(exe fmt::fmt otherExe)
We want a list of all library binary files (by using $<TARGET_LINKER_FILE:tgt>) for dependent targets fmt::fmt and otherExe to generate the apropriate CGO interface.go file with CFLAGS and LDFLAGS.
The thing is, its hard to write a loop in CMake to iterate over link dependencies of target since
properties like LINK_LIBRBARIES and INTERFACE_LINK_LIBRARIES are in general lists but might contain generator expressions, as in the case for interface library target fmt::fmt which comes from Conan where INTERFACE_LINK_LIBRARIES resolves to
$<$<CONFIG:Release>:CONAN_LIB::fmt_fmt_RELEASE;>. which contains a semicolon ";" which is then treated itself as a list with $<$<CONFIG:Release>:CONAN_LIB::fmt_fmt_RELEASE; and >.
This is due to that Conan adds the following
set_property(TARGET fmt::fmt
PROPERTY INTERFACE_LINK_LIBRARIES
$<$<CONFIG:Release>:${fmt_LIBRARIES_TARGETS_RELEASE}
${fmt_OBJECTS_RELEASE}> APPEND)
Anybody has a solution to this?
We found a solution by using the file-api of Cmake, we setup a "configure" add_custom_target in CMake which is a pyhton script which is reading the reply for the 'codemodel-v2' (file-api): parsing the JSON output file for the target of interest. Then
gathering all linker and compiler flags from this JSON and then configure a Go file with these flags.
Include files have been extracted by passing $<TARGET_PROPERTY:targetName,INCLUDE_DIRECTORIES> to the add_custom_command.
I have 2 folders "inc" and "lib" in my project which have headers and static libs respectively. How do I tell cmake to use those 2 directories for include and linking respectively?
The simplest way of doing this would be to add
include_directories(${CMAKE_SOURCE_DIR}/inc)
link_directories(${CMAKE_SOURCE_DIR}/lib)
add_executable(foo ${FOO_SRCS})
target_link_libraries(foo bar) # libbar.so is found in ${CMAKE_SOURCE_DIR}/lib
The modern CMake version that doesn't add the -I and -L flags to every compiler invocation would be to use imported libraries:
add_library(bar SHARED IMPORTED) # or STATIC instead of SHARED
set_target_properties(bar PROPERTIES
IMPORTED_LOCATION "${CMAKE_SOURCE_DIR}/lib/libbar.so"
INTERFACE_INCLUDE_DIRECTORIES "${CMAKE_SOURCE_DIR}/include/libbar"
)
set(FOO_SRCS "foo.cpp")
add_executable(foo ${FOO_SRCS})
target_link_libraries(foo bar) # also adds the required include path
If setting the INTERFACE_INCLUDE_DIRECTORIES doesn't add the path, older versions of CMake also allow you to use target_include_directories(bar PUBLIC /path/to/include). However, this no longer works with CMake 3.6 or newer.
You had better use find_library command instead of link_directories. Concretely speaking there are two ways:
designate the path within the command
find_library(NAMES gtest PATHS path1 path2 ... pathN)
set the variable CMAKE_LIBRARY_PATH
set(CMAKE_LIBRARY_PATH path1 path2)
find_library(NAMES gtest)
the reason is as flowings:
Note This command is rarely necessary and should be avoided where there are other choices. Prefer to pass full absolute paths to
libraries where possible, since this ensures the correct library will
always be linked. The find_library() command provides the full path,
which can generally be used directly in calls to
target_link_libraries(). Situations where a library search path may be
needed include: Project generators like Xcode where the user can
switch target architecture at build time, but a full path to a library
cannot be used because it only provides one architecture (i.e. it is
not a universal binary).
Libraries may themselves have other private library dependencies that
expect to be found via RPATH mechanisms, but some linkers are not able
to fully decode those paths (e.g. due to the presence of things like
$ORIGIN).
If a library search path must be provided, prefer to localize the
effect where possible by using the target_link_directories() command
rather than link_directories(). The target-specific command can also
control how the search directories propagate to other dependent
targets.
might fail working with link_directories, then add each static library like following:
target_link_libraries(foo /path_to_static_library/libbar.a)
I want to use a tree parsing library (NHParser) in my code. I have make-installed the library in /home/ikram/parser (with include files in /home/ikram/parser/include/NHparser/ and lib files in /home/ikram/parser/lib/ directory).
I am wondering if, in the first place, I can just add the library and include file in my main CMakeLists.txt file without resorting to FindNHPARSER.cmake script? If yes, how I may achieve that?
I tried the above but couldn't succeed so I wrote FindNHPARSER.cmake like the following.
find_path(NHPARSER_INCLUDE_DIR include/NHparser/NHparser.h
HINTS PATH_SUFFIXES NHparser)
find_library(NHPARSER_LIBRARY NAMES NHparser)
set(NHparser_LIBRARIES ${NHparser_LIBRARY})
set(NHparser_INCLUDE_DIRS ${NHparser_INCLUDE_DIR})
include(FindPackageHandleStandardArgs)
mark_as_advanced(NHparser_INCLUDE_DIR NHparser_LIBRARY )
Is it correctly written? How I can include this in my main CMakeLists.txt script and do I need to set CMAKE_MODULE_PATH while running cmake?
Thanks for your time.
For such a small (fairly standard) find process, I'd just add the code directly to the main CMakeLists.txt.
You can move it to a separate .cmake file if you prefer - then you'd just include that file at the appropriate point in your main CMakeLists.txt.
As for the code, I'd keep it pretty simple; essentially just a find_path and find_library call along with checks that the relevant things were actually found:
find_path(NHPARSER_INCLUDE_DIR NAMES NHparser.h PATH_SUFFIXES NHparser)
if(NOT NHPARSER_INCLUDE_DIR)
message(FATAL_ERROR "Didn't find NHparser.h")
endif()
find_library(NHPARSER_LIBRARY NAMES NHparser)
if(NOT NHPARSER_LIBRARY)
message(FATAL_ERROR "Didn't find NHparser library")
endif()
The you can use the variables like:
include_directories(${NHPARSER_INCLUDE_DIR})
...
target_link_libraries(MyExe ${NHPARSER_LIBRARY})
The variables are unlikely to be found unaided though, since the install prefix for this library on your machine seems to be "/home/ikram/parser". Since this location is probably specific to your own machine, I wouldn't hard-code that into your CMakeLists.txt.
Instead, to have CMake add that path to the list of default search paths, just set CMAKE_PREFIX_PATH when you invoke CMake:
cmake . -DCMAKE_PREFIX_PATH=/home/ikram/parser
I'm currently trying to get CMake running for my project (on windows). I want to use a custom location where all libraries are installed. To inform CMake about that path I tried to do that:
set(CMAKE_PREFIX_PATH D:/develop/cmake/libs)
But when I try to find the library with
find_library(CURL_LIBRARY NAMES curl curllib libcurl_imp curllib_static)
CMake can't find it.
When I set my prefix path to
set(CMAKE_PREFIX_PATH D:/develop/cmake/libs/curl)
... the library is located.
So my question is:
How can I configure CMake properly to work with a directory structore at a custom location which looks like that:
D:/develop/cmake/libs/
-> libA
-> include
-> lib
-> libB
-> include
-> lib
-> ...
-> include
-> lib
In "include" lie the public headers and in "lib" are the compiled libraries.
edit:
The current workaround for me is, to do this before i search for libraries:
set(CUSTOM_LIBRARY_PATH D:/develop/cmake/libs)
file(GLOB sub-dir ${CUSTOM_LIBRARY_PATH}/*)
foreach(dir ${sub-dir})
if(IS_DIRECTORY ${dir})
set(CMAKE_PREFIX_PATH ${CMAKE_PREFIX_PATH};${dir})
endif()
endforeach()
But that way the default module for boost wont find it until it because the directory structore of boost is a bit different.
boost -> include -> boost-1_50 -> *.hpp
When I move the content if "boost-1_50" to "include" the library can be found but that way it's not possible to handle multiple versions right?
The simplest solution may be to add HINTS to each find_* request.
For example:
find_library(CURL_LIBRARY
NAMES curl curllib libcurl_imp curllib_static
HINTS "${CMAKE_PREFIX_PATH}/curl/lib"
)
For Boost I would strongly recommend using the FindBoost standard module and setting the BOOST_DIR variable to point to your Boost libraries.
I saw that two people put that question to their favorites so I will try to answer the solution which works for me:
Instead of using find modules I'm writing configuration files for all libraries which are installed. Those files are extremly simple and can also be used to set non-standard variables. CMake will (at least on windows) search for those configuration files in
CMAKE_PREFIX_PATH/<<package_name>>-<<version>>/<<package_name>>-config.cmake
(which can be set through an environment variable).
So for example the boost configuration is in the path
CMAKE_PREFIX_PATH/boost-1_50/boost-config.cmake
In that configuration you can set variables. My config file for boost looks like that:
set(boost_INCLUDE_DIRS ${boost_DIR}/include)
set(boost_LIBRARY_DIR ${boost_DIR}/lib)
foreach(component ${boost_FIND_COMPONENTS})
set(boost_LIBRARIES ${boost_LIBRARIES} debug ${boost_LIBRARY_DIR}/libboost_${component}-vc110-mt-gd-1_50.lib)
set(boost_LIBRARIES ${boost_LIBRARIES} optimized ${boost_LIBRARY_DIR}/libboost_${component}-vc110-mt-1_50.lib)
endforeach()
add_definitions( -D_WIN32_WINNT=0x0501 )
Pretty straight forward + it's possible to shrink the size of the config files even more when you write some helper functions. The only issue I have with this setup is that I havn't found a way to give config files a priority over find modules - so you need to remove the find modules.
Hope this this is helpful for other people.
Use CMAKE_PREFIX_PATH by adding multiple paths (separated by semicolons and no white spaces). You can set it as an environmental variable to avoid having absolute paths in your cmake configuration files
Notice that cmake will look for config file in any of the following folders
where is any of the path in CMAKE_PREFIX_PATH and name is the name of the library you are looking for
<prefix>/ (W)
<prefix>/(cmake|CMake)/ (W)
<prefix>/<name>*/ (W)
<prefix>/<name>*/(cmake|CMake)/ (W)
<prefix>/(lib/<arch>|lib|share)/cmake/<name>*/ (U)
<prefix>/(lib/<arch>|lib|share)/<name>*/ (U)
<prefix>/(lib/<arch>|lib|share)/<name>*/(cmake|CMake)/ (U)
In your case you need to add to CMAKE_PREFIX_PATH the following two paths:
D:/develop/cmake/libs/libA;D:/develop/cmake/libB
There is no way to automatically set CMAKE_PREFIX_PATH in a way you want. I see following ways to solve this problem:
Put all libraries files in the same dir. That is, include/ would contain headers for all libs, lib/ - binaries, etc. FYI, this is common layout for most UNIX-like systems.
Set global environment variable CMAKE_PREFIX_PATH to D:/develop/cmake/libs/libA;D:/develop/cmake/libs/libB;.... When you run CMake, it would aautomatically pick up this env var and populate it's own CMAKE_PREFIX_PATH.
Write a wrapper .bat script, which would call cmake command with -D CMAKE_PREFIX_PATH=... argument.
You have one extra level of nesting.
CMAKE will search under $CMAKE_PREFIX_PATH/include for headers and $CMAKE_PREFIX_PATH/libs for libraries.
From CMAKE documentation:
For each path in the CMAKE_PREFIX_PATH list, CMake will check
"PATH/include" and "PATH" when FIND_PATH() is called, "PATH/bin" and
"PATH" when FIND_PROGRAM() is called, and "PATH/lib and "PATH" when
FIND_LIBRARY() is called.
I've encountered a similar scenario. I solved it by adding in this following code just before find_library():
set(CMAKE_PREFIX_PATH /the/custom/path/to/your/lib/)
then it can find the library location.