I'm trying to get a native Windows build working in which we depend on librsvg-2. It's correctly installed through vcpkg. We usually build with cmake and have made a custom module to find this library. This works great in the unix world, but not within Windows and targeting either a Debug build or a Release build (from visual studio). This is due to the fact the actual lib file gets suffixed with a d on Windows.
This is our FindLibRSVG.cmake
include(LibFindMacros)
libfind_package(LibRSVG Cairo)
libfind_package(LibRSVG GDK-PixBuf)
libfind_pkg_detect(LibRSVG librsvg-2.0
FIND_PATH librsvg/rsvg.h PATH_SUFFIXES librsvg-2 librsvg-2.0
FIND_LIBRARY rsvg-2
)
libfind_process(LibRSVG)
To get the build working on Windows i have to specify a flag to our cmake command like this:
cmake .. -DLibRSVG_LIBRARY=./vcpkg_installed/x64-windows/debug/lib/rsvg-2.40d.lib
Do note the d at the end of the library.
I know there is a cmake module SelectLibraryConfigurations available but i'm not quite sure how to use this properly.
What i'd like to achieve is to be able to build in debug mode without having to provide this flag.
Note: The LibFindMacros implementation can be found here
Related
Our Android application consists of 40-some Android Library Modules (ALMs), each of which also builds a C++ shared library with externalNativeBuild and CMake. So far we had the dependencies between these libs set up like this:
The dependent ALM references the dependency ALM with api project(':lib')
The dependent CMake script references the dependency .so with add_library(SHARED IMPORTED lib) and set_target_properties(lib PROPERTIES IMPORTED_LOCATION ...) and a relative path.
Recently we had to upgrade to the latest Android API version. This started off a cascade because now we were getting deprecated warnings in code generated by the navigation-ktx library, but upgrading that requires upgrading Gradle and the Android Gradle plugin. After that I started getting errors like liblib.so, needed by 'project', missing and no known rule to make it.
It looks like the latest Gradle parallelizes build tasks more heavily, and this means the dependent CMake/Ninja builds are being started concurrently with their dependencies, resulting in this error because the dependency is not yet built. I figured out that what we were doing was not entirely supported, but there is a "supported" way to do that now, so I refactored our entire build to use Prefab.
Now I started getting other errors, alternating between:
1.
C++ build system [prefab] failed while executing ...
Usage: prefab [OPTIONS] PACKAGE_PATH...
Error: Invalid value for "PACKAGE_PATH": Directory ... is not readable.
ld: error: undefined symbol ...
I looked into build/intermediates and found that in the 2nd case, the cmake config script was generated incorrectly: instead of add_library(lib::lib SHARED IMPORTED ) it had add_library(lib::lib INTERFACE IMPORTED) like it it was a header only library, and there was no IMPORTED_LOCATION set in the file.
What am I doing wrong and what should I do to unbreak our build?
It looks like the toolchain support for prefab interdependencies within a project is not quite finished. Others are reporting the same kind of errors at https://issuetracker.google.com/issues/265544858:
This appears to be a race condition with generating prefab cmake files.
It says in https://issuetracker.google.com/issues/221231432 that the header-only cmake config is generated to satisfy Android Studio's IDE features (completion, etc.) before the library is actually built.
Treat as-yet-unconfigured modules as if they are Header-only libraries for Android Studio purposes. This works because Android Studio doesn't care about linker flags for the purposes of providing language services.
I'm a *nix user, installing LLVM is easy for me, just download the precompiled file, set LLVM_DIR, and you're done. But I'm having a lot of problems with Windows ...
I downloaded LLVM-<version>-win64.exe from the GitHub release, but I can't find LLVMConfig.cmake file. Then I tried to compile LLVM from the source following this documentation.
When I started compiling my own project, I got this error:
'C:/<...>/Debug/libLLVMSupport.lib', needed by '<...>.exe', missing and no known rule to make it
I guess maybe I'm missing some compile options. but I can't find the documentation for LLVM_ENABLE_PROJECTS or BUILD_SHARED_LIBS, not even a list of component names.
I tried to add -DBUILD_SHARED_LIBS=ON but CMake told me BUILD_SHARED_LIBS option is not supported on Windows.
I am using CMake to build a Qt5 project on OS X. I need to create a build process that is as simple as possible for others.
By default Qt5 installs to the home folder on OS X. However, it then places its files within a directory named after the exact version number, e.g. 5.2.1.
At the moment I am using these lines in my CMake file:
set(QT5_PATH $ENV{HOME}/Qt5.2.1/5.2.1/clang_64/ CACHE PATH "Path to Qt5")
set(QT5_MODULE_PATH ${QT5_PATH}/lib/cmake)
set(CMAKE_PREFIX_PATH ${CMAKE_PREFIX_PATH} ${QT5_MODULE_PATH})
This works, but unfortunately breaks with each minor update of Qt as the 5.2.1 needs to be changed to 5.2.2, etc.
In Windows there are environment variables that can be used to find Qt. Is there anything similar in OS X that I can use within CMake to find a Qt installation?
Use find_package instead of juggling with the paths yourself. Then your users can rely on standard CMake mechanism instead of figuring out your own CMake code.
Use find_package(Qt5Widgets) to get targets like Qt::Widgets to link against and for the includes.
Similar for Qt5Core and whatever part of Qt 5 you need.
See Qt's documentation: http://doc.qt.io/qt-5/cmake-manual.html
I'm currently building a compiler/interpreter in C/C++.
When I noticed LLVM I thought it would fit greatly to what I needed and so I'm trying to integrate LLVM in my existing build system (I use CMake).
I read this bout integration of LLVM in CMake. I copy and pasted the example CMakeLists.txt, changed the LLVM_ROOT to ~/.llvm/ (that's where I downloaded and build LLVM and clang) and it says it isn't a valid LLVM-install. Best result I could achieve was the error message "Can't find LLVMConfig" by changing LLVM_ROOT to ~/.llvm/llvm.
My ~/.llvm/ folder looks like this:
~/.llvm/llvm # this folder contains source files
~/.llvm/build # this folder contains object, executable and library files
I downloaded LLVM and clang via SVN. I did not build it with CMake.
Is it just me or is something wrong with the CMakeLists.txt?
This CMake documentation page got rotted, but setting up CMake for LLVM developing isn't different from any other project. If your headers/libs are installed into non-standard prefix, there is no way for CMake to guess it.
You need to set CMAKE_PREFIX_PATH to the LLVM installation prefix or CMAKE_MODULE_PATH to prefix/share/llvm/cmake to make it work.
And yes, use the second code snippet from documentation (under Alternativaly, you can utilize CMake’s find_package functionality. line).
This has been asked here before but I couldn't find a solution which works for me.
Sample CMakeLists.txt file for LLVM project - This was the original question.
However, there are a couple of issues I am facing when making a project with LLVM.
Platform: Windows 7
Compiler: MingW
1) Firstly, I am using the svn version of llvm which is currently at 3.1. Currently, Binaries for MingW are not present for llvm 3.0 too so I decided to go with the latest itself and build it with mingw. So although the build works fine, I cannot seem to find the llvm-config perl script in the bin folder. I tried searching the entire dir yet I can only find an llvm-config folder and a dependencies file.
2) I tried building llvm for Visual studio 2010 yet that didn't work with cmake so I had to use MingW.
3) Now, this is sequence in which I add libs to CMake -
LLVMXCoreInfo
LLVMMipsAsmPrinter
LLVMMipsCodeGen
LLVMMipsInfo
LLVMMBlazeAsmPrinter
LLVMMBlazeCodeGen
LLVMMBlazeInfo
LLVMLinker
LLVMipo
LLVMInterpreter
LLVMInstrumentation
LLVMJIT
LLVMExecutionEngine
LLVMMC
LLVMBitWriter
LLVMX86Disassembler
LLVMX86AsmParser
LLVMX86AsmPrinter
LLVMX86CodeGen
LLVMX86Info
LLVMAsmParser
LLVMARMAsmParser
LLVMMCParser
LLVMARMAsmPrinter
LLVMARMCodeGen
LLVMARMInfo
LLVMArchive
LLVMBitReader
LLVMSelectionDAG
LLVMAsmPrinter
LLVMCodeGen
LLVMScalarOpts
LLVMInstCombine
LLVMTransformUtils
LLVMipa
LLVMAnalysis
LLVMTarget
LLVMMC
LLVMCore
LLVMSupport
imagehlp
psapi
m
4) However, adding InitializeNativeTarget(), starts giving me linking errors which I think come because of the dependencies not being in right order.
5) I want to use the llvm_map_components_to_libraries(REQ_LLVM_LIBRARIES jit native) and hence I added this to my CMakeLists.txt
INCLUDE(cmake/LLVM-Config.cmake)
However, this doesn't work. CMake Error at cmake/LLVM-Config.cmake:141 (message):
Library `jit' not found in list of llvm libraries.
Now, the question is really too long but I basically wanted to ask what is the best way to do this in CMake. Could someone post the entire thing (for windows).
Also, is there a way to build it for VS 2010. I tried the instructions on CLang site but those gave me this error in CMake.
" string sub-command REGEX, mode MATCH needs at least 5 arguments total to command."
I really need some help figuring out how to get dependencies to work in llvm and for it to build with VS. I would really appreciate some help.