using a custom compiler flag in cmake? - c++

I'm trying to compile some code I found on GitHub https://github.com/tapio/Wendy
I'm just trying to compile the stuff in tests/. I never had any experience with cmake, but they're kinda logical anyway.
I got stuck at the part where cmake does this:
/usr/bin/c++ CMakeFiles/clear.dir/clear.o -o clear -rdynamic -lwendy -lglfw -lGLEW -lglm -lz
and gets this error:
Linking CXX executable clear
/usr/bin/ld: cannot find -lwendy
/usr/bin/ld: cannot find -lglm
collect2: ld returned 1 exit status
make[3]: *** [clear] Error 1
make[2]: *** [CMakeFiles/clear.dir/all] Error 2
make[1]: *** [CMakeFiles/clear.dir/rule] Error 2
make: *** [clear] Error 2
I don't understand how the Wendy and glm folder became a compiler flag. Somebody please explain how this is possible. :(

In tests/CMakeLists.txt the line target_link_libraries(${test} wendy ${WENDY_LIBRARIES}) instructs cmake to link the list of libraries in WENDY_LIBRARIES to the executable.

Related

static link glibc & boost_python36 for python extension

I'm writting a extension for pyton3.6. My develop machine run gcc7.3, and production environment os is centos6. I use the following link option to static link glibc to avoid upgrade glibc2.12 to glibc2.14+.
-Wl,-Bdynamic -lpython3.6m -Wl,-Bstatic -lboost_python36
But get error:
[ 50%] Linking CXX shared module helloext.so
/usr/bin/x86_64-linux-gnu-ld: cannot find -lgcc_s
/usr/bin/x86_64-linux-gnu-ld: cannot find -lgcc_s
collect2: error: ld returned 1 exit status
CMakeFiles/helloext.dir/build.make:94: recipe for target 'helloext.so' failed
make[2]: *** [helloext.so] Error 1
CMakeFiles/Makefile2:67: recipe for target 'CMakeFiles/helloext.dir/all' failed
make[1]: *** [CMakeFiles/helloext.dir/all] Error 2
Makefile:83: recipe for target 'all' failed
make: *** [all] Error 2
Anyone known? Thanks.
The reason might be although libgcc is present it may not be in the paths known to ldconfig. Check this by doing
/sbin/ldconfig -p | grep libgcc
Does the output show that there is a link to libgcc corresponds to paths that you have listed above?
A work around for you may be to add the link to the relevant library to your compile command e.g.
... -L /usr/lib/gcc/x86_64-linux-gnu/4.6/
Another may be to create a symbolic link to the library yourself.
ln -s /usr/lib/gcc/x86_64-linux-gnu/4.6/libgcc_s.so /usr/lib/gcc/libgcc_s.so
You have not informed us about Linux you are using. Update 4.6 with the proper number in the command above.

collect2.exe: error: ld returned 5 exit status

I've recently updated all msys2 packages and now I can't build my project.
The error occurs at the moment of linking one of .dlls - target_library.dll.
The error message isn't clear to me. What does status 5 mean?
collect2.exe: error: ld returned 5 exit status
Full message:
g++ -Wl,-s,--relax,--gc-sections -shared -Wl,-subsystem,windows -mthreads -Wl,--out-implib,C:/msys64/workspace/Project_Root_Directory/project/src/../build/release/plugins/libtarget_library.dll.a -o ../../../../build/release/plugins/target_library.dll object_script.target_library.Release -lglu32 -lopengl32 -luser32 -LC:/msys64/workspace/Project_Root_Directory/project/build/release -LC:/msys64/workspace/Project_Root_Directory/project/third-party/out/lib -LC:/msys64/workspace/Project_Root_Directory/project/deps/lib -lexif -ldecimal -lsqlite3 -lutils -LC:/Python35/libs -lpython35 -lkmlbase -lkmlengine -lkmldom -lkmlxsd -lminizip -luriparser -lkmlconvenience -lcore -lrender -lraster -lgui -LC:/msys64/workspace/Project_Root_Directory/project/deps/lib/target_library/win64 -LC:/msys64/mingw64/lib C:/msys64/mingw64/lib/libQt5Widgets.dll.a C:/msys64/mingw64/lib/libQt5WinExtras.dll.a C:/msys64/mingw64/lib/libQt5Gui.dll.a C:/msys64/mingw64/lib/libQt5Network.dll.a C:/msys64/mingw64/lib/libQt5Concurrent.dll.a C:/msys64/mingw64/lib/libQt5Xml.dll.a C:/msys64/mingw64/lib/libQt5Core.dll.a
collect2.exe: error: ld returned 5 exit status
make[4]: *** [Makefile.Release:159: ../../../../build/release/plugins/target_library.dll] Error 1
make[4]: Leaving directory '/workspace/Project_Root_Directory/project/src/modules/plugins/target_library'
make[3]: Leaving directory '/workspace/Project_Root_Directory/project/src/modules/plugins/target_library'
make[2]: *** [Makefile:384: sub-target_library-make_first] Error 2
make[2]: Leaving directory '/workspace/Project_Root_Directory/project/src/modules/plugins'
make[1]: *** [Makefile:297: sub-plugins-make_first] Error 2
make[1]: Leaving directory '/workspace/Project_Root_Directory/project/src/modules'
make: *** [Makefile:44: sub-modules-make_first] Error 2
gcc 7.1.0, Qt5 5.9.1, qmake, Win7 x64
I had the same issue.
I link my project with static library.
After mingw64 upgrade, my project stoped building with the same error.
I found out that debug version built successfully. So i compared linker flags. In release version Qt add this flags "-Wl,-s,--relax,--gc-section".
I couldn't find any information about "-s" flag, but due to this link i figured out that -gc-section flag was the reason of fail.
I added the following code to my .pro-file, and it worked
mingw {
contains(QT_ARCH, x86_64): {
LIBS+=-Wl,--no-gc-sections
}
}
Just in case someone finds this due the same problem, please, add the following flag to your compiler -Wl,--verbose (or --verbose to the linker). This will show which library was not found or give you more information about the problem.

Linking library with gcc - ld: cannot find -larpack

I am installing software on a server with no root privileges. I come across the following error during installation:
make[1]: *** [hgaprec] Error 1
make[1]: Leaving directory `/seq/.../SOFTWARE/hgaprec/src'
make: *** [all-recursive] Error 1
Making install in src
make[1]: Entering directory `/seq/.../SOFTWARE/hgaprec/src'
g++ -O3 -o hgaprec ratings.o main.o log.o hgaprec.o -larpack -llapack -
lblas -lgsl -lpthread -lgslcblas
/.../software/free/Linux/redhat_6_x86_64/pkgs/gcc_5.2.0/bin/ld: cannot
find -larpack
collect2: error: ld returned 1 exit status
make[1]: *** [hgaprec] Error 1
make[1]: Leaving directory `/seq/.../SOFTWARE/hgaprec/src'
make: *** [install-recursive] Error 1
Since library arpack could not be found, I then installed it here /seq/.../SOFTWARE/hgaprec/ARPACK and found that the process generated a static file libarpack_LINUX.a. To link this static library to gcc the following command was used:
gcc -larpack -L/seq/.../SOFTWARE/hgaprec/ARPACK/libarpack_LINUX.a
However, I keep getting the same error while installation of the software that larpack was not found. Am I using the linking command wrong?
You either want gcc main.c /seq/../SOFTWARE/hgaprec/ARPACK/libarpack_LINUX.a (you don't need -l and -L if you're specifying the full path to static library), or as #Julian_Cienfuegos suggested gcc main.c -L/seq/../SOFTWARE/hgaprec/ARPACK/ -larpack_LINUX. This assumes you're only compiling a single file called main.c which contains your main() function, and outputs the a.out binary.
EDIT: Added explanation of main.c.
My issue got solved after including the ARPACK library path as part of LD flag in configure like so:
./configure --prefix=/seq/.../SOFTWARE/hgaprec LDFLAGS="-L/seq/.../SOFTWARE/hgaprec/ARPACK/"

Building error, cmake, can not be used when making a shared object; recompile with -fPIC

When I build a project with cmake, I got following error. Though I tried to add compiling flag -fPIC by add_definition() in the CMakeLists.txt, this error persists. Can anyone help? I am a new guy to cmake. Any suggestions will be highly appreciated.
/usr/bin/ld: /act/mvapich2-1.9/gcc-4.7.2/lib/libmpich.a(mvapich_malloc.o): relocation R_X86_64_32S against `.bss' can not be used when making a shared object; recompile with -fPIC
/act/mvapich2-1.9/gcc-4.7.2/lib/libmpich.a: could not read symbols: Bad value
collect2: error: ld returned 1 exit status
make[2]: *** [src/libstracker.so] Error 1
make[2]: Leaving directory `/home/xxxx/success/AutomaDeD-master'
make[1]: *** [src/CMakeFiles/stracker.dir/all] Error 2
make[1]: Leaving directory `/home/xxxx/success/AutomaDeD-master'
make: *** [all] Error 2
add_definitions is is intended to add preprocessor definitions, not a flag
-fPIC is present by default in the linker flags for a shared library build with GCC, see Modules/Compiler/GNU.cmake. You can see all flags by running make VERBOSE=1.
As for the error itself, see this answer.

Issue with CMake project building

I have the following problem. On my Ubuntu I try to build a project and receive the following linker error(s) so far:
/usr/bin/ld:
/usr/lib/gcc/x86_64-linux-gnu/4.8/../../../x86_64-linux-gnu/libboost_thread.a(once.o): undefined reference to symbol 'pthread_once##GLIBC_2.2.5'
/lib/x86_64-linux-gnu/libpthread.so.0: error adding symbols: DSO
missing from command line collect2: error: ld returned 1 exit status
make[2]: *** [sunprint] Error 1 make[1]: ***
[CMakeFiles/sunprint.dir/all] Error 2 make: *** [all] Error 2
*** Failure: Exit code 2 ***
I'm running under ubuntu 13 desktop, GCC 4.8, boost ver. is 1.54. As an IDE I'm working with
is the KDevelop.
I can provide any additional info about this issue if needed, but now I'm stuck with
this linking problem.
Any ideas?
Thanx in advance.
add_definitions only adds inputs for the preprocessor, which is in action even before the compiler starts its business and even much farther away from linking the executable, the step ld is supposed to be doing.
What you want to have ld resolve link-time dependencies is the CMake command target_link_libraries, which, for a given target, add a number of libs to link against after compilation.
In you case, the appropriate invocation could look like this
target_link_libraries(${PROJECT_NAME} [...] -lpthread [...]) #obviously without the '[...]' and the correct target name
I had a similar problem but with mpich. Both:
target_link_libraries(${PROJECT_NAME} [...] -lmpich [...])
and
target_link_libraries(${PROJECT_NAME} [...] mpich [...])
worked properly.