I am compiling a rather big C++ project with cmake.
The project has several targets defined in the CMakeLists.txt of the various subdirectories
I can create a folder somewhere and use cmake to prepare compilation of the targets, and compile any of the target :
cmake ..
make -j8 cytosim
And this works.
However, if I call cmake with a target :
cmake .. --target cytosim
I get the error
CMake Error: The source directory ".../build/cytosim" does not exist.
I thought target was supposed to be a module/library/executable target... What am I missing ?
CMake --target argument is usable in CMake Build Mode (--build).
Try cmake --build .. --target cytosim
Related
I need to build my CMake based project under MSVC 2013 and MSVC 2019.
With MSVC 2019 using Ninja generator I build it successfully with following commands:
cmake -S . -B build -GNinja "-DCMAKE_BUILD_TYPE:STRING=Release"
cmake --build build --target all
On MSVC 2013 I have no Ninja available, so I tried the following:
cmake -S . -B build -DCMAKE_BUILD_TYPE:STRING=Release
cmake --build build --target all
Anyway I am getting following error and nothing is built:
MSBUILD : error MSB1009: Project file does not exist.
Switch: all.vcxproj
Any idea how to build it without ninja? (I cannot install it, since I am building it on a build server.)
In contrast to other generators (like Makefiles or Ninja) CMake does not generate an all target for Visual Studio solution but an ALL_BUILD target.
So cmake --build build --target ALL_BUILD --config Release should succeed.
I want to create a shared library from cmake . I have a simple test.cpp .
My CMakeLists.txt looks like below
cmake_minimum_required(VERSION 2.8)
project (test)
set(CMAKE_BUILD_TYPE Release)
#include_directories(${CMAKE_CURRENT_SOURCE_DIR}/include)
add_library(test SHARED /home/tuhin/test/test1/test.cpp)
But I am not able to find "test" which my .so, I have seen test.dir folder created but not .so
Please help me to understand the issue.
(I suppose you read the comments and acted accordingly...)
(I also suppose you need a way to find out where your library will be placed, from within CMake build system)
The disk location of any target does not depend on CMakeLists.txt only, but also on the choice of the generator. Multi config generators like Visual Studio something, or Xcode might append configuration name as an additional directory, so you may get different results just by choosing a different generator.
This means that there is no easy way to uniquely identify disk location during configure stage. On the other hand, you may very easily check that information during the build stage:
cmake_minimum_required(VERSION 3.15)
project (lib_file_name)
add_library(my_test_lib SHARED my_test_lib.cpp)
add_custom_target(output_lib_name
ALL
COMMAND ${CMAKE_COMMAND} -E echo "my_test_lib location: $<TARGET_FILE:my_test_lib>"
)
note add_custom_target line:
new target was added, named output_lib_name
it will be executed as a part of building the default target (-> ALL)
command to build this target is asking cmake to output the file name of the target in question, using CMAke generator expressions (--> COMMAND ${CMAKE_COMMAND} -E echo "my_test_lib location: $<TARGET_FILE:my_test_lib>")
If you run it with makefile generator:
$ cmake -S /tmp -B /tmp/make-build -G "Unix Makefiles" ; cmake --build /tmp/make-build
-- Configuring done
-- Generating done
-- Build files have been written to: /tmp/make-build
Scanning dependencies of target my_test_lib
[ 50%] Building CXX object CMakeFiles/my_test_lib.dir/my_test_lib.cpp.o
[100%] Linking CXX shared library libmy_test_lib.dylib
[100%] Built target my_test_lib
Scanning dependencies of target output_lib_name
my_test_lib location: /tmp/make-build/libmy_test_lib.dylib
[100%] Built target output_lib_name
Note the line
my_test_lib location: /tmp/make-build/libmy_test_lib.dylib
if you run it with Xcode generator:
configure:
$ cmake -S /tmp -B /tmp/xcode-build -G Xcode
-- Configuring done
-- Generating done
-- Build files have been written to: /tmp/xcode-build
build release configuration:
$ cmake --build /tmp/xcode-build --config Release
........... lot of output deleted ...........
my_test_lib location: /tmp/xcode-build/Release/libmy_test_lib.dylib
** BUILD SUCCEEDED **
build debug configuration:
$ cmake --build /tmp/xcode-build --config Debug
........... lot of output deleted ...........
my_test_lib location: /tmp/xcode-build/Debug/libmy_test_lib.dylib
** BUILD SUCCEEDED **
Note how the location is different for different configuration builds, without any change in CMake build system.
At the end, this is the cmake documentation about add_custom_command, cmake generator expressions.
I'm trying to build this
https://github.com/patrikhuber/eos
but I'm having troubles.
The instructions are pretty simple, as it says on gitHub
To build:
git clone --recursive https://github.com/patrikhuber/eos.git
mkdir build && cd build # creates a build directory next to the 'eos' folder
cmake -G "<your favourite generator>" ../eos -DCMAKE_INSTALL_PREFIX=../install/
make && make install # or open the project file and build in an IDE like Visual Studio
I'm using "Ninja" as generator and it looks like the cmake part goes through successfully as I get
-- Configuring done
-- Generating done
-- Build files have been written to: /home/francesco/eos/build
That's where things stop "working" for me, or where I fail to understand what's next. Following the instructions, I type
make && make install
and I get this message
make: *** No targets specified and no makefile found. Stop.
I looked around for solutions but I don't really understand what I am supposed to do: I tried
./configure
but I'm getting
bash: ./configure: No such file or directory
Anyone can please help?
Thanks
It always depends on your CMake "Generator". The 'make' is linux/mingw tool/command. For VisualStudio you can use nmake or sln/proj generated stuff.
More reliable could be utilize CMake for building i.e. for "NMake Makefiles" generator:
cmake --build <build folder> --target install
or
cmake --build <build folder> --config release --target install
for VisualStudio generator
I had the same problem, and solved by tinkering with locations for cmake and make. Here's what I used:
cmake -DCMAKE_INSTALL_PREFIX=/usr/local
make
I believe /usr/local is the default location (see here)
Currently, I have CMakeLists and hoge.cpp in a directory, and running CMakeLists and make command generates hoge executable file.
Now I added hoge2.cpp and want to be able to generate two different hoge and hoge2 executable files by running CMakeLists and "make hoge" and "make hoge2" commands.
How can I do this?
Create two build targets in your CMakeLists.txt file.
add_executable( hoge hoge.cpp )
add_executable( hoge2 hoge2.cpp )
Then you can run (from same directory as your CMakeLists.txt file,
cmake --build . --target hoge
For the other build target use
cmake --build . --target hoge2
You can refer to the CMake documentation or the man pages for more information. Try running CMake with just the --build flag to get help.
I am writing a library that contains library itself and examples and I am using CMake:
cmake_minimum_required(VERSION 3.6)
add_executable (example main.cpp)
install(DIRECTORY include DESTINATION include PATTERN ".DS_Store" EXCLUDE)
When I am running cmake --build . --target install - it compiles example target and makes installation of include directory
I want to exclude building example target and make only include directory installation when building install target and building example if running without any special target:
Here I want example to be NOT built:
cmake --build . --target install
Here I want example to be built:
cmake --build .
How should I change my CMakeLists.txt to make it work as I want?
You cannot exclude single CMake target when installing.
The problem is that 'install' target may depends only from 'all' (default) target.
While you may remove 'install' -> 'all' dependency (by setting CMAKE_SKIP_INSTALL_ALL_DEPENDENCY variable), you may not add another dependency for 'install'.
So, before installing
cmake --build . --target install
either performs
cmake --build .
or doesn't build anything (even library, which you want to build in any case).