Cmake add link dll when I run .*.exe - cmake

I have a ..dll. My ..exe must include this dll file.
I have seen this link How to use external DLLs in CMake project, but this is correct for me.
How to add search dll path in cmake?

Related

Build gtest as shared library (dll) in CMake

I have never worked with CMake before, so please forgive any rookie mistakes. Most of the following working frame has been given to me by my project group.
The goal is to build GoogleTest into a .dll, to be used in different, indepentent parts of our project. I'm having troubles setting up CMake the right way.
The work-flow so far has been:
Clone gtest from git --> also downloads a CMake List file
Alter variables in CMakeCache.txt to have it produce a Code::Blocks project file
Compile the project file in Code::Blocks
So far, it produces a static library (.a files) that can be used in our project. I'm having troubles genereating .dll files.
Variables I have tried changing:
BUILD_SHARED_LIBS:BOOL=ON --> the files generated by Code::Blocks now have a .dll.a double extension
CMAKE_C_FLAGS and all the corresponding C++ flags where set to -DGTEST_CREATE_SHARED_LIBRARY=1 as given here
CMAKE_EXE_LINKER_FLAGS has been set to -shared to make the linker produce .dll files
I have worked my way through the GoogleTest documentation here and here but in both, building it into a .dll is merely a 2-sentence-topic.
As #Tsyvarev pointed out, the .dll files were created in a (very) different folder.

Creating a findable shared library with cmake

I am rewriting libraries from hand-written Makefiles to using cmake. I am getting stuck at the point where I need to library library A from library B.
I can find the libraries using find_package, but when they are being linked cmake complains about not having a rule for building the .so file because it is looking for it in the build directory instead of the installed directory.
This is explained if I look at the /usr/lib/cmake/library/libraryConfigVersion.cmake file, which contains this hardcoded path. This file was created with the following steps:
write_basic_package_version_file(
"${CMAKE_CURRENT_BINARY_DIR}/libraryConfigVersion.cmake"
VERSION ${LIBRARY_VERSION}
COMPATIBILITY AnyNewerVersion
)
export(EXPORT libraryTargets
FILE "${CMAKE_CURRENT_BINARY_DIR}/library/libraryConfigVersion.cmake"
NAMESPACE library::
)
(i have replaced my library name with 'library'). How can I get cmake to write the correct path so that I can easily link against my library from other cmake projects?
Command export actually exports build tree. This is explicitely written in the documentation.
For export install tree, use install(TARGETS ... EXPORT) plus install(EXPORT). Both flows are described in documentation for install command.
See also CMake tutorial Exporting and Importing Targets.

Building third party library as part of CMake project

I have a top level CMakeLists.txt file which builds a library called Camellia and several executables in subdirectories which link with Camellia. I would like to add a third party library called XDMF as a dependency for Camellia under Camellia/TPL/Xdmf. Luckily, XDMF is already on a CMake build system, but when I use
add_subdirectory(TPL/Xdmf)
and then
add_library(Camellia ${LIB_SOURCES} ${HEADERS})
it builds Camellia in the build/TPL/Xdmf/bin directory rather than build as it does without the add_subdirectory(TPL/Xdmf). Why does adding a subdirectory change the build directory for Camellia, and how do I fix it? Also how do I make sure Camellia is linking with Xdmf once I get that figured out?
I think that ExternalProject_Add(...) is what you want.
Please see CMake: How to build external projects and include their targets which describes a similar issue.

C++ Windows Application to include all dlls into an executable file

IDE: VS2005
Say I am using Poco library and the executable needs below dlls. I have to put them in same directory where the executable is.
msjava.dll
msvcp80.dll
msvcr80.dll
PocoFoundation.dll
PocoNet.dll
Is there any way that can build a dll-free executable? Thanks.
They don't have to be in the same directory. They can be in another directory if your PATH variables includes the directory they are in.
It looks like the Poco libraries can be downloaded as source, so you should be able to build them as static libraries and make a stand alone executable.
Update
For the msvc DLL's, you can build against static libraries. Bring up the properties of your project, go to C/C++, Code Generation and modify "Runtime Library". Make sure to choose a library other then "Multi-threaded DLL" or "Multi-threaded Debug DLL." You will also want to make sure you do that for the Poco libraries as well.

When to include .lib and when to include .dll or both

I got a .h file, two .lib files, a .dll file and a tiny test project from a hardware vendor to talk to their hardware.
Compiling and running their test project works just fine. Noteworthy: they don't use the .dll. I can throw the dll-directory and all of it's content away, everything works just fine.
To start things off I simply copied the communication parts of their code (connect, disconnect and send a command) into my project. This is actually all that you can do. I have included the .h file and pointed to the directory containing the .lib files. Just like in the tiny test project. It all compiles, but when I try to run the project complains that it is missing the .dll file.
Can anybody explain what is happening? How are libs and dlls supposed to work?
All of this is on windows, VS2005. I compared the .vcproj files and could not find any significant differences.
The test project is statically linked - the lib is included in the exe.
Your project is dynamically linked - the dll is referenced and therefore needed at runtime.
See this Stack Overflow question for more information.
Basically the answer depends on whether you are going to use static or dynamic linking for your executable.
With static linking, you need the .h and .lib files but not the .dll files to compile and link. Your executable will be larger but you won't need any of the .h/.lib/.dll files during runtime.
With dynamic linking, you just need the .h files to compile and link. Your executable will be smaller but you will need one or both of the .dll files during runtime.
For a more detailed treatment of this from the Visual Studio perspective, check out http://msdn.microsoft.com/en-us/library/1ez7dh12.aspx -
"Dynamic linking differs from static linking in that it allows an executable module (either a .dll or .exe file) to include only the information needed at run time to locate the executable code for a DLL function. In static linking, the linker gets all of the referenced functions from the static link library and places it with your code into your executable."