Getting CMake to find flex on Windows - windows

I am trying to use flex on a project and I am trying to use CMake to link flex with my project. I found a FindFLEX.cmake online which I am using for this. You can find it here. This was supposed to be in CMake by default, but I dont think it was. My directory structure is as follows
root
---src
---CMakeLists.txt
---cmake
---Modules
---FindFLEX.cmake
---build
---external
---flex - Where flex is installed
---bin
---flex.exe
---lib
---libfl.a
My src/CMakeLists.txt is as follows
cmake_minimum_required(VERSION 2.8)
set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake/Modules/")
message(${CMAKE_MODULE_PATH})
set( project_name "try_flex" )
message(${project_name})
project(${project_name})
find_package(FLEX)
FLEX_TARGET(Mylexer tokenize.lex ${CMAKE_CURRENT_BINARY_DIR}/tokenize.cpp)
add_executable(${project_name} ${FLEX_Mylexer_OUTPUTS})
target_link_libraries(${project_name} ${FLEX_LIBRARIES})
FLEX_TARGET is supposed to be provided by FindFLEX.cmake when it finds the Flex package. Running the following command in build/ directory didnt find the flex packages
build> cmake ..\src
Then I added the prefix and that worked partially
build> cmake -DCMAKE_PREFIX_PATH=c:\root\external\flex\ ..\src
That found the executable flex.exe , but not the library. The relevant portions of FindFLEX.cmake is shown below
FIND_PROGRAM(FLEX_EXECUTABLE flex DOC "path to the flex executable")
message("DEBUG:"${FLEX_EXECUTABLE})
MARK_AS_ADVANCED(FLEX_EXECUTABLE)
FIND_LIBRARY(FL_LIBRARY NAMES fl DOC "path to the fl library")
message("DEBUG:FL_LIBRARY"${FL_LIBRARY})
MARK_AS_ADVANCED(FL_LIBRARY)
SET(FLEX_LIBRARIES ${FL_LIBRARY})
The message I get on running cmake is
DEBUG:c:/root/external/flex/bin/flex.exe
DEBUG:FL_LIBRARYFL_LIBRARY-NOTFOUND
CMake Error: The following variables are used in this project, but they are set to NOTFOUND.
Please set them or make sure they are set and tested correctly in the CMake file s:FL_LIBRARY (ADVANCED)
linked by target "try_flex" in directory C:/root/src
-- Configuring incomplete, errors occurred!
Could anyone tell me why I am finding the flex binary but not the library after including the prefix path? Any help would be appreciated.
Thanks

I figured out what the problem is. On Windows, cmake is looking for libfl.lib. But the Windows installation of Flex provides only libfl.a So I needed to add these two lines to my cmake
LIST(APPEND CMAKE_FIND_LIBRARY_SUFFIXES ".a")
FIND_LIBRARY(FL_LIBRARY NAMES libfl fl DOC "path to the fl library")
The first line adss .a to list of suffixes searched for libraries, and the second line looks for libfl. That worked

Related

Use framework in static library

I have a library which is being generated as .a file (to be statically linked). There I want to include Qt framework (QtCore.framework) since I am on OSX. Is that possible? How could I do it using cmake?
My attempt:
In CMakeLists.txt I have
FIND_LIBRARY(QTCORE_LIBRARY NAMES QtCore
HINTS "${CMAKE_SOURCE_DIR}/osx/frameworks")
Then I print variable ${QTCORE_LIBRARY} and it gives right path.
Then in src/CMakeLists.txt (where my sources are) I link the library
TARGET_LINK_LIBRARIES(libname $${QTCORE_LIBRARY})
However when I launch the compilation it complains because it does not find
fatal error: 'QtGlobal' file not found
I have checked and QtCore.framework contains QtGlobal header
EDIT: In case someone has same problem I found solution.
I needed to add "${QTCORE_LIBRARY}/Headers" in my project include directories
Thanks in advance and regards
Why don't using the CMake "config.cmake" provided by Qt5 ?
something like:
# Qt Setting
set(CMAKE_AUTOMOC ON)
set(CMAKE_AUTOUIC ON)
set(CMAKE_AUTORCC ON)
find_package(Qt5 REQUIRED COMPONENTS Core Gui Widgets)
...
target_link_libraries(libname Qt5::Core Qt5::Gui Qt5::Widgets)
CMake can find and use [...] Qt5 libraries. [...] Qt5 libraries are found using “Config-file Packages” shipped with Qt5
src: https://cmake.org/cmake/help/latest/manual/cmake-qt.7.html
In order for find_package to be successful, Qt 5 must be found below the CMAKE_PREFIX_PATH, or the Qt5_DIR must be set in the CMake cache to the location of the Qt5WidgetsConfig.cmake file. The easiest way to use CMake is to set the CMAKE_PREFIX_PATH environment variable to the install prefix of Qt 5.
src: http://doc.qt.io/qt-5/cmake-manual.html

compiling SFML with cmake and mingw under windows

When i try to run cmake to build a project where i include the SFML library i get the following Error: SFML found but version too low (requested: 2.4, found: 1.x.x)
I downloaded only the source of the newest Version of the library (SFML-2.4.2). I than run cmake (with MinGW Makefiles) And build the binaries into the same folder.
I copied the FindSFML into an subfolder of my project.
After that i had the following folder structure
SFML-2.4.2\
cmake\
Modules\
FindSFML.cmake
CMakeFiles
doc
...
include
lib
src
..
sfml-games\
tetris\
cmake_modules\
FindSFML.cmake
CMakeLists.txt
main.cpp
tetris-build
...
My CMakeLists.txt contains the following stuff:
project(Tetris)
cmake_minimum_required(VERSION 2.8)
aux_source_directory(. SRC_LIST)
set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake_modules")
Find_package(SFML 2 REQUIRED system window graphics network audio)
include_directories(${SFML_INCLUDE_DIR})
add_executable(${PROJECT_NAME} ${SRC_LIST})
target_link_libraries(${PROJECT_NAME} ${SFML_LIBRARY})
I found that in cmake the entry CMAKE_INSTALL_PREFIX (which i dont get) is set to C:\Program Files (x86)\SFML so i put the library and the lib of SFML into C:\Program Files (x86)\SFML. (what is that CMAKE_INSTALL_PREFIX and should i realy always copy the library and lib folders into my C:\Program Files (x86)\ ??). Now my cmake runs through but when i try to compile the code i get a lot of undifined references to '_imp__....'
By the way on linux i just installed SFML via sudo apt-get install libsfml-dev and it works out of the box.
You're confusing things. CMAKE_INSTALL_PREFIX is the default location where to put SFML when you build the install target (i.e. running make install). This has nothing to do with your other issues.
You don't have to install SFML (or any other library) somewhere under C:\Program Files. That's completely up to you.
What I found to be rather neat is installing MinGW to C:\usr (or creating a symlink to your installation folder) and also use that path for CMAKE_INSTALL_PREFIX when building SFML.
This way MinGW should behave pretty much the way you're used to from Linux (i.e. not having to specify paths for include dir or libraries etc.).
As for your undefined reference errors, you should create a new question only asking for these (and then include at least a few of them), as they have nothing to do with the installation directory.
Right now I can only guess, but it's most likely due to you using the wrong CMake variables for the linker. You won't notice this on Linux, since SFML will be in the default search path (which will also happen if you use C:\usr as described above).
To try fixing this, use this line:
target_link_libraries(${PROJECT_NAME} ${SFML_LIBRARIES} ${SFML_DEPENDENCIES})

Add libraries Qt and LuaJIT / Lua51 with CMake

I am trying to use CMake with Qt and LuaJIT that will run on Visual Studio 2012. I managed somehow to run Qt, but i don't know how to add LuaJIT library to project. I am using source of LuaJIT cloned from http://luajit.org/git/luajit-2.0.git, which is build by running .bat file.
I dont care that LuaJIT will be build by CMake, i just need to link library and add headers to project.
I removed lib folder from my project... Is not worth troubles to have dependancies coupled with project whitout cmake file :D
My project hierarchy is:
+lib
-luajit-2.0
+src
-my sources
+ui
-ui files
-CMakeLists.txt
And CMakeLists.txt file looks like this:
cmake_minimum_required(VERSION 2.8.12)
set(PROJECT "Grapedit")
project(${PROJECT})
# Qt Stuff
set(CMAKE_INCLUDE_CURRENT_DIR ON)
set(CMAKE_AUTOMOC ON)
find_package(Qt5Widgets REQUIRED)
set(SOURCE_FILES
src/main.cpp
src/mainwindow.h
src/mainwindow.cpp
)
set(UI_FILES
ui/mainwindow.ui
)
source_group("UI Files" FILES ${UI_FILES})
qt5_wrap_ui(UI_HEADERS ${UI_FILES})
source_group("Generated UI Headers" FILES ${UI_HEADERS})
add_executable(${PROJECT} ${SOURCE_FILES} ${UI_HEADERS} ${UI_FILES})
qt5_use_modules(${PROJECT} Widgets)
My solution
So it is finally working and I made couple of newbie mistakes... :)
I will write them down for others:
didn't know what is find module... This will search environment and set up locations of libraries or flag that it didn't find them. Since LuaJIT is compatible with Lua51 you can use find_package(Lua51).
Your libraries must be some way visible to CMake. On Windows simplest way is to add them to PATH variable. Or you can add path of your libraries to CMake variable CMAKE_PREFIX_PATH. Open find module, for example FindLua51.cmake and you will see how must be your library organized. On windows I've must installed LuaJIT manualy - created LuaJIT folder and I've put *.h files to include subfolder, *.dll to bin subfolder and *.lib to lib subfolder. Then add bin folder to PATH and set LUA_DIR to LuaJIT folder.
use include_directories on include folder
then you must link libraries target_link_libraries, but after add_executable!
My CMakeLists.txt file:
cmake_minimum_required(VERSION 2.8.12)
# Declare project variables...
set (PROJECT "Grapedit")
set (
SOURCE_FILES
src/main.cpp
src/mainwindow.h
src/mainwindow.cpp
)
set(UI_FILES
ui/mainwindow.ui
)
# Set project name
project(${PROJECT})
# Include Lua directories
include_directories(${LUA_INCLUDE_DIR})
# Qt Stuff
set(CMAKE_INCLUDE_CURRENT_DIR ON)
set(CMAKE_AUTOMOC ON)
# Find packages...
# Will find also LuaJIT, but must be named same as Lua51 and installed into directories
find_package(Lua51)
# Find Qt modules, every module separately
find_package(Qt5Widgets REQUIRED)
# Create nice groups in IDEs
source_group("UI Files" FILES ${UI_FILES})
source_group("Generated UI Headers" FILES ${UI_HEADERS})
# Use Qt UI files
qt5_wrap_ui(UI_HEADERS ${UI_FILES})
# Create executable
add_executable (
${PROJECT}
${SOURCE_FILES}
${UI_HEADERS}
${UI_FILES}
)
# Link libraries...
# Must be after executable is created!
# Link Qt modules
qt5_use_modules (
${PROJECT}
Widgets
)
# Link Lua
target_link_libraries(${PROJECT} ${LUA_LIBRARIES})
# Will not show new windows prompt when running program
if (MSVC)
set_target_properties(${PROJECT} PROPERTIES
WIN32_EXECUTABLE YES
LINK_FLAGS "/ENTRY:mainCRTStartup"
)
endif ()
You are missing the actual linkage which you can amend with the following statement:
target_link_libraries(${PROJECT} luajit-5.1)
For sure, it would be even better if this lua jit could have a cmake find module, or config/version file depending on its exact build system.
You could grab the find module from here:
https://github.com/brimworks/lua-zlib/blob/master/cmake/Modules/FindLuaJIT.cmake
Then you could link against it as follows:
target_link_libraries(${PROJECT} ${LUA_LIBRARIES})
You can see that it would become more dynamic this way rather than hard-coding the exact name. The details for figuring out that would be left with the find module.
Note that you would probably need to use the corresponding variables for the header inclusion then as follows:
include_directories(${LUA_INCLUDE_DIR})
This will take care of automatically finding the include directory, respectively, without you hard-coding it.
You would also need to add the following line into your CMakeLists.txt:
set(CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake)
and you need to place the downloaded find module into a "cmake" subfolder.
Please refer to the following page for further details about this topic in general:
CMake:How To Find Libraries

CMAKE: Build library and link against it

I'm trying to use cmake (on Linux with GNU make and g++) to build a project with two sub-directories: MyLib and MyApp. MyLib contains source for a static library; MyApp needs to link against that library. I'm trying to build on Linux with generated makefiles using the following CMakeLists.txt:
cmake_minimum_required (VERSION 2.6)
project (MyProj)
include_directories (MyLib)
file(GLOB MyLibSrc MyLib/*.cpp)
add_library(MyLibrary STATIC ${MyLibSrc})
file(GLOB MyAppSrc MyApp/*.cpp)
add_executable(MyApplication ${MyAppSrc})
target_link_libraries(MyApplication MyLibrary)
This 'almost' works. It fails at link time because while it generates libMyLibrary.a - it is in the root. When I add:
link_directories(${MyProj_BINARY_DIR})
it makes no difference.
I've got a few (inter-linked) questions:
What's the best way to coerce cmake into building my library and executable into a 'staging directory' — say MyStage — to keep targets separate from source?
How do I convince cmake to link the application against the library?
If I wanted to build a debug and a release version, what's the best way to extend my cmake scripts to do this — making sure that the debug application links against the debug library and the release application against the release library?
I'm a relative newcomer to cmake. I've read what I can find on the web, but find myself struggling to get my library to link with my executable. This sort of a configuration, to my mind, should be quite common. An example from which to crib would be very helpful, but I've not found one.
Well, it is better to read this example and do exactly as suggested.
cmake_minimum_required (VERSION 2.6)
project (MyProj CXX)
add_subdirectory(MyLib)
add_subdirectory(MyApp)
Then for each subdirectory specified, CMakeLists.txt files are created
MyLib\CMakeLists.txt
file(GLOB SRC_FILES *.cpp)
add_library(MyLib ${SRC_FILES})
MyApp\CMakeLists.txt
file(GLOB SRC_FILES *.cpp)
add_executable(MyApp ${SRC_FILES})
target_link_libraries(MyApp MyLib)
Use "out of the source build". Make a directory used only for build and while in it, call
cmake <path to the sources, it may be relative>
Either use
link_directories(${MyProj_BINARY_DIR}/MyLib)
or make CMakeLists.txt in each subdirectory - that would be better for project larger than very small.
This is a bit tricky, check out CMAKE_BUILD_TYPE in the docs (you can set it and/or "if" by it). You can also set it from command line:
cmake -DCMAKE_BUILD_TYPE=Debug
I've discovered the 'optimal' solution to (1)... so, thought I should post it here:
SET(CMAKE_ARCHIVE_OUTPUT_DIRECTORY MyStage)
SET(CMAKE_RUNTIME_OUTPUT_DIRECTORY MyStage)
The thing that confused me previously is that static libraries are not considered a LIBRARY by Cmake - they're considered to be ARCHIVEs.
Do not add libraries and executables in the root Cmakelists.txt. Add these libraries and executables in Cmakelists.txt of subdirectories.

building boost locale library on Windows

I am trying to build the boost::locale library (http://cppcms.sourceforge.net/boost_locale/html/tutorial.html#a5771bce93e200c36f7cd9dfd0e5deaa) which is still in review for integration into boost but the cmake command throws up the following:
D:\lib\boost_locale_v2.92\build>cmake ..
-- Looking for ICU libraries
-- Looking for iconv
-- Looking for Boost
CMake Error: The following variables are used in this project, but they are se
to NOTFOUND.
Please set them or make sure they are set and tested correctly in the CMake fi
s:
BOOST_THREAD
linked by target "boost_locale-static" in directory D:/lib/boost_locale_v2
2
ICU_DATA
linked by target "boost_locale-static" in directory D:/lib/boost_locale_v2
2
ICU_I18N
linked by target "boost_locale-static" in directory D:/lib/boost_locale_v2
2
ICU_INCLUDE_DIR
used as include directory in directory D:/lib/boost_locale_v2.92
ICU_UC
linked by target "boost_locale-static" in directory D:/lib/boost_locale_v2
2
-- Configuring incomplete, errors occurred!
I have got ICU and boost but can't figure out how to modify the out-of-box cmake script for boost::locale. Any help is appreciated
Actually these error messages are clear enough. You need to point where is what: boost thread library location, ICU include directory, and others.
Read the installation instructions carefully:
http://cppcms.sourceforge.net/boost_locale/html/building_boost_locale.html
You need to provide:
cmake -DCMAKE_INCLUDE_PATH=/path/to/boost/include;path/to/icu/include -DCMAKE_LIBRARY_PATH=/path/to/icu/lib ..

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