lets say my makefile looks like this:
CXX = g++
OGLLIBS = -lglut32 -lglu32 -lopengl32
projname : projname.o
${CXX} -o projname $< ${OGLLIBS}
Then in which directory does g++ look for the libraries? I was assuming . but if I put the libs there it still complains about not finding them (*.lib is the correct file or does unix use another ending?!)
Folders
unix uses the folders /lib (for system lib) and /usr/lib
your own libraries or newly installed should be in /usr/local/lib but you need to add "-I/usr/local/lib" as compiler flag.
file ending
is .so for shared libs basicly
looking for libs
your can tell your compiler to add other directories to look for libs by setting a variable called LD_LIBRARY_PATH=/root-to-my-libs
Related
I find myself going against the grain configuring cmake paths with ccmake over and over again as with every change of for ex. compiler some of my library paths get lost.
In particular paths to (unlinked) lapack, lapacke, gsl get either lost or set to system defaults instead the ones I've installed with brew.
There has to be a way to tell cmake to "ignore" system libraries and instead look in homebrew paths (say. /opt/homebrew/lib, /opt/homebrew/include etc.).
I'd prefer not to link those libraries as this is not recommend and I'm not experienced in switching environments.
[EDIT] MRE:
git clone https://gitlab.physik.uni-muenchen.de/AG-Scrinzi/tRecX.git
cd tRecX
cmake . -DCMAKE_BUILD_TYPE=Parallel
make -j 8
I add the following to .bash_profile/.zshrc:
export LDFLAGS="-L/opt/homebrew/opt/lapack/lib -L/opt/homebrew/opt/lapack/lib"
export CPPFLAGS="-I/opt/homebrew/opt/lapack/include -I/opt/homebrew/opt/openblas/include"
export PKG_CONFIG_PATH="/opt/homebrew/opt/lapack/lib/pkgconfig /opt/homebrew/opt/openblas/lib/pkgconfig"
then I try:
cmake . -DCMAKE_PREFIX_PATH=/opt/homebrew -DCMAKE_FIND_FRAMEWORK=NEVER -DCMAKE_FIND_APPBUNDLE=NEVER -DCMAKE_FIND_USE_CMAKE_SYSTEM_PATH=FALSE -DCMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH=FALSE -DMPI_CXX_COMPILER=/opt/homebrew/bin/mpicxx -DMPI_C_COMPILER=/opt/homebrew/bin/mpicc -DCMAKE_CXX_COMPILER=/opt/homebrew/bin/g++-11 -DCMAKE_C_COMPILER=/opt/homebrew/bin/gcc-11
The most common solution is to just set CMAKE_PREFIX_PATH to /opt/homebrew. CMake will then look preferentially in /opt/homebrew for everything. Since you're on Apple, you might need to set CMAKE_FIND_FRAMEWORK and CMAKE_FIND_APPBUNDLE to LAST or NEVER, too.
You can skip the standard platform search paths by setting CMAKE_FIND_USE_CMAKE_SYSTEM_PATH to FALSE at the command line, in a preset, or in a toolchain file. You might also wish to disable looking at the PATH environment variable by setting CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH to FALSE.
Finally, if you're in a cross-compiling scenario or toolchain file, you can change the definition of the system directories by setting CMAKE_SYSROOT. Note that the sysroot will have to contain the language runtime libraries (e.g. glibc) and will be passed to the --sysroot flag (or equivalent). Just be aware of those effects, too.
All of this is documented here:
https://cmake.org/cmake/help/latest/command/find_package.html#search-procedure
https://cmake.org/cmake/help/latest/variable/CMAKE_FIND_FRAMEWORK.html#variable:CMAKE_FIND_FRAMEWORK
https://cmake.org/cmake/help/latest/variable/CMAKE_FIND_APPBUNDLE.html#variable:CMAKE_FIND_APPBUNDLE
The following homebrew.cmake toolchain file worked for me:
set(HOMEBREW_PREFIX "/usr/local"
CACHE PATH "Path to Homebrew installation")
set(CMAKE_C_COMPILER "${HOMEBREW_PREFIX}/bin/gcc-11")
set(CMAKE_CXX_COMPILER "${HOMEBREW_PREFIX}/bin/g++-11")
set(CMAKE_PREFIX_PATH
"${HOMEBREW_PREFIX}"
# These libraries are keg-only and not loaded into
# the root prefix by default (to avoid clashes).
"${HOMEBREW_PREFIX}/opt/lapack"
"${HOMEBREW_PREFIX}/opt/openblas"
"${HOMEBREW_PREFIX}/opt/gcc/lib/gcc/11"
)
list(TRANSFORM CMAKE_PREFIX_PATH APPEND "/include"
OUTPUT_VARIABLE CMAKE_CXX_STANDARD_INCLUDE_DIRECTORIES)
set(CMAKE_C_STANDARD_INCLUDE_DIRECTORIES "${CMAKE_CXX_STANDARD_INCLUDE_DIRECTORIES}")
set(CMAKE_FIND_FRAMEWORK NEVER)
set(CMAKE_FIND_APPBUNDLE NEVER)
set(CMAKE_FIND_USE_CMAKE_SYSTEM_PATH FALSE)
set(CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH FALSE)
I built with the following commands:
$ ls
tRecX homebrew.cmake
$ cmake -G Ninja -S tRecX -B tRecX-build \
-DCMAKE_TOOLCHAIN_FILE=$PWD/homebrew.cmake \
-DCBLAS=/usr/local/opt/openblas/lib/libblas.dylib \
-DCMAKE_EXE_LINKER_FLAGS="-Wl,-undefined,dynamic_lookup" \
-DCMAKE_SHARED_LINKER_FLAGS="-Wl,-undefined,dynamic_lookup" \
-DCMAKE_BUILD_TYPE=Parallel
[ ... output clipped ... ]
Boost found -- full functionality
Build "Parallel" with C++ flags -D_USE_BOOST_ -O3 -pthread -D_USE_FFTW_, return to default by -UCMAKE_BUILD_TYPE
Compiler: /usr/local/bin/g++-11, change by -DCMAKE_CXX_COMPILER=[path_to_complier]
-- Linking to libraries Boost::system;Boost::filesystem;/usr/local/lib/libfftw3.dylib;/usr/local/opt/gcc/lib/gcc/11/libgfortran.dylib;alglib;/usr/local/lib/libarpack.dylib;Boost::system;Boost::filesystem;/usr/local/opt/lapack/lib/liblapacke.dylib;/usr/local/opt/openblas/lib/libblas.dylib;/usr/local/opt/lapack/lib/liblapack.dylib;/usr/local/opt/lapack/lib/libblas.dylib;m
-- Configuring done
-- Generating done
-- Build files have been written to: /Users/alexreinking/Development/tRecX-build
$ cmake --build tRecX-build
I had to set CBLAS manually because libblas.dylib provides the OpenBLAS CBLAS interface, but the build system specifically looks for a library named libcblas. There's no other option in this case.
The code and build have issues with its linking model and dependencies. I was able to paper over these by setting -Wl,-undefined,dynamic_lookup. However, note that this will just defer linker errors to runtime and might impose a large startup cost.
If you can make commits to the project, I would store these settings in a preset, maybe name it homebrew-parallel or something:
-DCMAKE_TOOLCHAIN_FILE=$PWD/homebrew.cmake \
-DCBLAS=/usr/local/opt/openblas/lib/libblas.dylib \
-DCMAKE_EXE_LINKER_FLAGS="-Wl,-undefined,dynamic_lookup" \
-DCMAKE_SHARED_LINKER_FLAGS="-Wl,-undefined,dynamic_lookup" \
-DCMAKE_BUILD_TYPE=Parallel
Then you could just run cmake --preset=homebrew-parallel
So I am trying to include an installed Fortran library to a CMake project. I know the directory where the module (.mod) file is located, but my project can't seem to find it unless I set CMAKE_Fortran_MODULE_DIRECTORY.
SET(LIB_INCLUDE_DIR /usr/local/include)
SET(EX_FILES main.f90 file1.f90 file2.f90)
INCLUDE_DIRECTORIES(${LIB_INCLUDE_DIR})
ADD_EXECUTABLE(test ${EX_FILES})
TARGET_LINK_LIBRARIES(test lib1)
Where the error is
use lib1
1
Fatal Error: Can't open module file 'lib1.mod' for reading at (1): No such file or directory
unless I include the line
SET(CMAKE_Fortran_MODULE_DIRECTORY ${LIB_INCLUDE_DIR})
And then it can find the file just fine. But I'm running into a little problem. By setting CMAKE_Fortran_MODULE_DIRECTORY, CMake tries to write all generated modules to this directory rather than the CMAKE_BINARY_DIR (where I would like it).
From the documentation, I know that CMAKE_Fortan_MODULE_DIRECTORY is meant to be set to specify where to write generated module files, but some compilers look to that directory to find modules. Is there any way to set multiple directories so that if it can't find in/write to one directory, it searches the second? When I try to set CMAKE_Fortran_MODULE_DIRECTORY to be multiple directories, it only looks at the first directory.
If it helps I am on a Ubuntu 14.04 LTS system using gfortran 4.8.4
EDIT:
So by Alexander Vogt's suggestion I ran with VERBOSE=1 and got
cd /home/user/Repos/build/src && gfortran -I/home/user/Repos/build/src -isystem /usr/local/include -c /home/user/Repos/test_project/src/main.f90 -o CMakeFiles/test.dir/main.f90.o
when I did NOT set CMAKE_Fortran_MODULE_DIRECTORY and
cd /home/user/Repos/build/src && gfortran -J/usr/local/include -I/home/user/Repos/build/src -isystem /usr/local/include -c /home/user/Repos/test_project/src/main.f90 -o CMakeFiles/test.dir/main.f90.o
when I did.
It seems the only difference is the -J flag, which sets exactly what CMAKE_Fortran_MODULE_DIRECTORY sets. Is there some flag that sets just where to look for compiled modules, and not where to put them?
I'm building and distributing an executable which relies on several 3rd-party libraries, most of which are built outside of CMake's buildsystem (though, if it helps, I can add and build them as custom targets in my CMake file).
Here's how I include the libs:
target_link_libraries(MyApp
Lib1_x64
Lib2_x64
etc.}
I'd like to include a CMake directive which installs my executable along with its dependencies. Is there a better way to do this other than calling the install command for every single dependency?
install(DIRECTORY ${DEV_PATH}/Release/ DESTINATION lib FILES_MATCHING PATTERN "libLib1*" PATTERN "*.svn" EXCLUDE PATTERN "*-obj" EXCLUDE)
Is there maybe a way to do this via the add_library command?
This is possible in nowadays with CMake 3.21, which allows you to get a set of dependent libraries via parameter RUNTIME_DEPENDENCY_SET in the install command. Keep in mind, that it will gather all dependent libraries including system, you will need to filter them.
cmake_minimum_required(VERSION 3.21)
# Install your app or library
install(
TARGETS ${PROJECT_NAME}
RUNTIME_DEPENDENCY_SET runtime_deps
)
# Install third-party libraries (exclude system libraries Windows/Unix)
LIST(APPEND pre_exclude_regexes "api-ms-.*")
LIST(APPEND pre_exclude_regexes "ext-ms-.*")
LIST(APPEND post_exclude_regexes ".*WINDOWS[\\/]system32.*")
LIST(APPEND post_exclude_regexes "^/lib" "^/usr" "^/bin")
install(RUNTIME_DEPENDENCY_SET runtime_deps
PRE_EXCLUDE_REGEXES ${pre_exclude_regexes}
POST_EXCLUDE_REGEXES ${post_exclude_regexes}
)
Sorry, no. The add_library command serves the purpose of creating a target in your makefile to build a library. target_link_dependencies just passes the various -L ... -l ... flags to the compiler for a target.
The normal CMake approach is to test for the presence of other libraries or executables on which yours depends, and fail if they are not available.
Handling dependencies is normally left to a package manage such as apt, rpm, etc. It is unwise to build your dependent components as part of your own makefile for a number of reasons:
Your clients might want to use a slightly different version
Any change in how those dependencies build requires you to modify your own build scripts
Your program may work with multiple versions of a dependency, all of which build in different ways.
As someone who uses CMake to build large parts of an entire embedded Linux distribution (see Open webOS), I advise you to keep your scripts focused very tightly on building just one thing.
I am also finding a way to deal this problem today.
and I found :
include(ExternalProject)
ExternalProject_Add()
does it!
here is my sample CMakeLists.txt:
cmake_minimum_required(VERSION 3.13)
project(third-party-build)
include(ExternalProject)
ExternalProject_Add(libuuid
PREFIX libuuid-prefix
# DOWNLOAD_DIR libuuid-download
# SOURCE_DIR libuuid-source
# DOWNLOAD_COMMAND wget xxx.com/xxx.tar.gz && tar zxf xxx.tar.gz
DOWNLOAD_COMMAND tar zxf ${PROJECT_SOURCE_DIR}/libuuid-1.0.3.tar.gz
CONFIGURE_COMMAND <DOWNLOAD_DIR>/libuuid-1.0.3/configure
BUILD_COMMAND ${MAKE}
BUILD_IN_SOURCE 1
INSTALL_COMMAND mkdir -p ${PROJECT_SOURCE_DIR}/lib/ && cp <SOURCE_DIR>/.libs/libuuid.a <SOURCE_DIR>/.libs/libuuid.so <SOURCE_DIR>/.libs/libuuid.so.1 <SOURCE_DIR>/.libs/libuuid.so.1.0.0 ${PROJECT_SOURCE_DIR}/lib/
LOG_DOWNLOAD 1
LOG_BUILD 1
# LOG_INSTALL 1
)
I'm trying to convert a build using Makefile that currently works for Unix and Windows. I have the following directory layout:
lib1
lib2
lib2 depends on lib1.
In lib1, I create on Unix a .o file using
ld -r obj1.o -o lib1.o'.
And in lib2, I also create a .o file using the lib1.o file created in the lib1 directory using:
ld -r obj2.o ../lib1/lib1.o -o lib2.o
On Windows it is very similar except we are creating a .lib file using the lib command in lib1:
lib -out:lib1.lib obj1.obj
and in lib2:
lib -out:lib2.lib obj2.obj ..\lib1\lib1.lib
Unfortunately, whatever I do, the lib1.o object file never appears when building lib2.o.
My CMakeLists.txt files are in lib1:
project (lib1)
add_library(lib1 obj1.c)
in lib2:
project (lib2)
add_library(lib2 obj2.c)
target_link_libraries(lib2 lib1)
and at the root I have:
project (root)
add_subdirectory(lib1)
add_subdirectory(lib2)
add_dependencies(lib2 lib1)
Is there something I'm missing to achieve this?
Thanks,
Manu
Let's say I have a simple hello project with the pseudo-standard directory layout
helloworld/
src/
main.c
say.c
say-helper.c
include/
say.h
say-helper.h
build/
and after running
cd ~/helloworld/build
cmake ..
make
I would expect the following
helloworld/
build/lib/
libsay.a
libsay.so
libsay.so.1.0.0
tmp/obj/
main.o
say.o
build/bin/
hello
and after make install I would expect
/usr/local/lib/
libsay.a
libsay.so
libsay.so.1.0.0
/usr/local/bin/
hello
What would the CMakeLists.txt look like for this setup?
I've been looking around for examples, but the only one I've found that shows how to add a library and an executable didn't work.
Basic commands to describe the project:
INCLUDE_DIRECTORIES(include)
ADD_LIBRARY(say src/say.c src/say-helper.c)
ADD_EXECUTABLE(hello src/main.c)
TARGET_LINK_LIBRARIES(hello say)
This is for placing the libs and the executable in the build directory, put that in your CMakeLists.txt:
SET (CMAKE_RUNTIME_OUTPUT_DIRECTORY ${PROJECT_BINARY_DIR}/bin)
SET (CMAKE_LIBRARY_OUTPUT_DIRECTORY ${PROJECT_BINARY_DIR}/lib)
SET (CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${PROJECT_BINARY_DIR}/lib)
For install you specify
install(TARGETS say hello
RUNTIME DESTINATION bin
LIBRARY DESTINATION lib
ARCHIVE DESTINATION lib)
in your CMakeLists.txt and set CMAKE_INSTALL_PREFIX to /usr/local in your configuration.
I'm not sure if you can build static and dynamic libraries simultaneously with the same name, though. And I don't know how to tell CMake to put the obj files in some specific location.