The static library is: /home/jonathan/Dropbox/C++/teapotgame/bin/liblua.a
The current gcc command im using is: gcc -std=c++11 -DLUA_USE_LINUX -D_REENTRANT -I/usr/include/SDL2 -lSDL2 -lSDL2_image -lGL -lGLU -lGLEW -lopenal files.o -o bin/bin
There's no principal difference whether you link against dynamic or static libraries (besides the -l prefix and omitting the file extension for shared libs). The order of the libraries can matter though. If you have circular dependencies, you have to list the same library twice.
Related
I am trying to build my .so library with all dependencies (mostly boost) statically linked. Currently, I can build statically linked static library and dynamically linked shared library:
I would like to add other dependencies to .so library so that it has 20MB and does not require user to install anything. Note that this is just a temporary solution before we upgrade to new Boost 1.55 on production servers.
I define libraries like this in Makefile ($ARCH can be either 32 or 64):
## Multi-arch library locations
LIB32=/usr/lib/i386-linux-gnu/
LIB64=/usr/lib/x86_64-linux-gnu/
LIBDIR:=$(LIB$(ARCH))
##Library directory
LIB=-L $(LIBDIR)
## DYNAMIC
LIBS=-lboost_serialization -lboost_thread -lboost_date_time -lboost_signals -lboost_iostreams -lboost_system -llog4cplus -lcrypto -lssl -lm
## STATIC
SLIBS=$(LIBDIR)libboost_serialization.a $(LIBDIR)libboost_thread.a $(LIBDIR)libboost_date_time.a $(LIBDIR)libboost_signals.a $(LIBDIR)libboost_iostreams.a $(LIBDIR)libboost_system.a $(LIBDIR)liblog4cplus.a
Shared lib with dynamic linking:
This is my shared lib GCC command:
Makefile:
$(CXX) $(CFLAGS) $(INCLUDE) $(LIB) $(LIBS) -shared -Wl,-soname,$(SHARED_LIB_VERSION) -o $(NEW_LIB_DIR)${SHARED_LIB_VERSION} $(OBJ_CPP_DYN) $(OBJ_C_DYN)
Changes into:
g++ -m64 -Wl,--trace -D NDEBUG -I /usr/include/ -I /usr/local/include -L /usr/lib/x86_64-linux-gnu/ -shared -lboost_serialization -lboost_thread -lboost_date_time -lboost_signals -lboost_iostreams -lboost_system -llog4cplus -lcrypto -lssl -lm -Wl,-soname,libLIBNAMEx64.so -o ../Release/libLIBNAMELIBNAMEx64.so ... and much more .o files ...
Linker says:
-lboost_serialization (/usr/lib/x86_64-linux-gnu//libboost_serialization.so)
-lboost_thread (/usr/lib/x86_64-linux-gnu//libboost_thread.so)
-lboost_date_time (/usr/lib/x86_64-linux-gnu//libboost_date_time.so)
-lboost_signals (/usr/lib/x86_64-linux-gnu//libboost_signals.so)
-lboost_iostreams (/usr/lib/x86_64-linux-gnu//libboost_iostreams.so)
-lboost_system (/usr/lib/x86_64-linux-gnu//libboost_system.so)
-llog4cplus (/usr/lib/x86_64-linux-gnu//liblog4cplus.so)
-lcrypto (/usr/lib/x86_64-linux-gnu//libcrypto.so)
-lssl (/usr/lib/x86_64-linux-gnu//libssl.so)
And it works.
Shared lib with static linking:
I thought I can just replace -shared with -static:
g++ -m64 -Wl,--trace -D NDEBUG -I /usr/include/ -I /usr/local/include -L /usr/lib/x86_64-linux-gnu/ -static -lboost_serialization -lboost_thread -lboost_date_time -lboost_signals -lboost_iostreams -lboost_system -llog4cplus -lcrypto -lssl -lm -Wl,-soname,libLIBNAMEx64_static_link.so -o ../Release/libLIBNAMEx64_static_link.so ... and much more .o files ...
But I get undefined reference errors everywhere.
So where do I configure how are dependencies linked with my binary? How can I achieve my goal?
More things I tried (edit)
-Wl,--library:
I also tried passing libraries directly to linker in a very assertive manner:
-Wl,--library=:/usr/lib/x86_64-linux-gnu/libboost_serialization.a
And without : (which prevents searching for .a):
-Wl,--library=/usr/lib/x86_64-linux-gnu/libboost_serialization.a
But I get the error:
/usr/bin/ld: cannot find -l/usr/lib/x86_64-linux-gnu/libboost_serialization.a
Of course, the file exists at that path.
Pass just library names:
Of course, here it's not even interpreted as linking command:
g++: error: libboost_serialization.a: No such file or directory
Interesting is that if I pass full path instead (/usr/lib/x86_64-linux-gnu/libboost_iostreams.a), GCC doubles it:
g++: error: /usr/lib/x86_64-linux-gnu//usr/lib/x86_64-linux-gnu/libboost_signals.a: No such file or directory
Use command man ld, I got this information:
-static
Do not link against shared libraries. It affects library searching for -l options which follow it. This option also implies --unresolved-symbols=report-all. This option can be used with -shared. Doing so means that a shared library is being created but that all of the library's external references must be resolved by pulling in entries from static libraries.
This option is exactly what you want: create a shared library with all dependencies (mostly boost) statically linked.
-l parameter is used to specify the library name, so you should use boost_serialization instead of /path/libboost_serialization.a:
-larchive
If you specify -lcommon, then ld will search its path-list for occurrences of "libcommon.a" for every common specified.
You can use -L parameter many times to specify the library paths when ld try to search static libraries:
-Lsearchdir
For example:
-L/usr/lib/x86_64-linux-gnu/
You could try -Wl,--whole-archive ${your library} -Wl,--no-whole-archive.
I have a makefile project in which I include a few different libraries. One of them is the boost library which I statically link in order to make my program portable. This is how my makefile command looks like:
g++ -O0 -g test.cpp testObject.o -pthread -I/home/user/devel/lmx-sdk-4.7.1/include/ -L/home/user/devel/lmx-sdk-4.7.1/linux_x64 -llmxclient -lrt -ldl -lboost_filesystem -lboost_system -static -static-libgcc -o $#
I have also linked lmx-sdk library to my project in order to use the licensing functionality; however, it seems to be that lmx-sdk doesn't seem to like static link as it gives an error "Using 'dlopen' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking".
How can I make it possible to link some libraries statically and the other ones dynamically ?
Thanks in advance
P.S. I have checked some of similar topics and tried a few methods which didn't work out for me.
Using -Wl,-Bdynamic and -Wl,-Bstatic instead of just using -Bdynamic and -Bstatic solved the problem.
The full link line looks like this now:
g++ -O0 -g test.cpp testObject.o -pthread -Bdynamic -I/home/user/devel/lmx-sdk-4.7.1/include/ -L/home/user/devel/lmx-sdk-4.7.1/linux_x64 -llmxclient -lrt -ldl -Wl,-Bstatic -lboost_filesystem -lboost_system -o $#
You can use -Bstatic to statically link what comes after it, then -Bdynamic to do the opposite. As many times as you need on the command line.
I have a makefile which looks like this .
DEFINES=-std=c++0x
INCS_GTK=-I/usr/include/gtk-2.0 -I/usr/include/glib-2.0 -I/usr/include/atk-1.0 -I/usr/include/cairo -I/usr/include/gdk-pixbuf-2.0 -I/usr/include/gtk-2.0/gdk -I/usr/include/pango-1.0 -I/usr/lib/gtk-2.0/include -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/lib/x86_64-linux-gnu/gtk-2.0/include
INCS=-I/usr/include/freetype2 -I/usr/include/mysql -Iframeworks ${INCS_GTK}
LDLIBS=-lconfig++ -lcxcore -lcv -lGL -lGLU -lglut -lhighgui -lSDL -lftgl -lueye_api -lboost_filesystem -lboost_system -lann -lpthread -lflycapture -lglog -lmysqlpp -lmysqlclient -lunittest++
DEBUG=-g -pg
WARNINGS=-Wall -Wextra -pedantic -Wno-long-long #-O3 -Weffc++
BUILDDIR=build
BINDIR=dist
MAINCXX=${shell find -name '*.cxx'}
TARGETS=${MAINCXX:%.cxx=%}
CXXFLAGS=${DEBUG} ${WARNINGS} ${DEFINES} ${INCS}
LDFLAGS=${DEBUG} ${WARNINGS} ${DEFINES}
include IDEconfigs/Makefile/generic.mk
I want to add the following paths of static libraries to the makefile .
/usr/local/lib/libYARP_OS.a /usr/local/lib/libYARP_sig.a /usr/local/lib/libYARP_math.a /usr/local/lib/libYARP_dev.a /usr/local/lib/libYARP_name.a /usr/local/lib/libYARP_init.a
how do i go about doing this .
Lets consider your /usr/local/lib/libYARP_OS.a.
What you can do is, have -L/usr/local/lib/ in your makefile as one of the variables. And then you can have -lYARP_OS appended to the LDLIBS.
-L is for path to the lib and -l is the lib name here libYARP_OS.a will be passed as -lYARP_OS.
On the command line you would do something like: gcc -o main main.c -L/usr/local/lib/ -lYARP_OS. This should give you an idea.
You can either use an -L<path> flag to tell GCC about the location of any library, and then include it with -l<libname>. For example this would be
$ gcc -o main main.c -L/usr/local/lib/ -lYARP_SO
as noted by swair.
Alternatively, you can also supply the full path of the static library and compile directly, like
$ gcc -o main main.c /usr/local/lib/libYARP_OS.a
See 'Shared libraries and static libraries' for details.
In your specific case I would add them to the LDLIBS= line.
NB: Be careful about linking order, this is relevant when linking programs together. See 'Link order of libraries' for details. For example:
$ gcc -Wall calc.c -lm -o calc (correct order)
works
$ cc -Wall -lm calc.c -o calc (incorrect order)
main.o: In function `main':
main.o(.text+0xf): undefined reference to `sqrt'
Also see this similar question: How to link to a static library in C?
Append -lYARP_OS -lYARP_sig -lYARP_math -lYARP_dev -lYARP_name -lYARP_init to LDLIBS.
Warning: the linking order may matter.
Also, be sure that the linker knows that /usr/local/lib is a place where to look for libraries, otherwise instruct it with -L/usr/local/lib (you could add another makefile variable, e.g. LIBPATHS or something similar, to contain the libraries paths).
As a general synopsis, if you have a library libMyLib.a in folder /my/path, the gcc (or g++) can be invoked with the following parameters:
gcc -L/my/path -lMyLib [...]
-L is used to include paths where the linker will look for libraries
-l is used to link a library, which must be passed without the lib prefix and the extension
This question may be useful for a general understanding of libraries usage in C and C++: How to use Libraries
In Makefile , add like this
USER_LIBS = -lYARP_OS -lYARP_sig -lYARP_math -lYARP_dev -lYARP_name -lYARP_init
This will link the libraries you required
I want to create a static library of all my files so that i could give my mylib.a file to others to execute on their system. I use opencv library in my code. I used the following command to compile my code.
g++ index.cpp -o display1 -Wl,-Bdynamic pkg-config --cflags --libs opencv -lglut -lGL -lGLU -Wl,-Bstatic mylib.a
But it is giving the following error.
/usr/bin/ld: cannot find -lgcc_s
collect2: ld returned 1 exit status
I believe the Kerrek SB is right in the comment. The command should be
g++ index.cpp -o display1 mylib.a $(pkg-config --cflags --libs opencv) -lglut -lGL -lGLU
Explanation:
The -Wl,-Bdynamic and -Wl,-Bstatic flags are useless. The linker automatically picks static or dynamic library depending on what it finds. If you give it path to a library (as you do with mylib.a) it can't choose and will link the library you provided. If you give it an -lX flag, it will look for libX.so or libX.a and link whichever it finds, but most Linux installations won't have static variants of system libraries, so there is nothing to choose from either.
It's worse, the -Wl,-Bdynamic and -Wl,-Bstatic are wrong. -Wl,-Bstatic prohibits linking of shared libraries. That has the side-effect of selecting static libgcc, which implicitly comes last on the linker command line. And you don't seem to have that installed. Most Linux systems don't.
Each object must be listed on the command-line before the libraries it refers to. I would expect mylib.a contains functions that need opencv or opengl, so it must be listed before those -l flags.
I'm trying to link to a static library, libcovis.a. Everything looks fine but I still have
undefined reference to `CoViG_PublicDemo::MoInS::reset()'
I checked that the name exists in the library
$nm libcovis.a | grep reset
...
_ZN16CoViG_PublicDemo5MoInS5resetEv
...
I'm using linking arguments -L/path/to/libcovis.a -lcovis
What am I doing wrong ?
Edit:
The error might be something else, if do
gcc main.cpp -I/usr/include/opencv -I/usr/include/cairo -I../../Source -o slam -rdynamic -lGLU -lGL -lSM -lICE -lX11 -lXext -lglut -lXi -lxml2 -lboost_filesystem-mt -llapack -lblas -lcv -lcxcore -lcvaux -lhighgui -lcairo ../../Source/libcovis.a ../../Source/contrib/gnuplot_i/libcovis_contrib_gnuplot_i.a -lgl2ps
It works !
But when I'm in KDevelop using cmake, I doesn't work anymore. I use
CMAKE_EXE_LINKER_FLAGS:STRING=-rdynamic -lGLU -lGL -lSM -lICE -lX11 -lXext -lglut -lXi -lxml2 -lboost_filesystem-mt -llapack -lblas -lcv -lcxcore -lcvaux -lhighgui -lcairo /usr/local/src/CoViS-0.0.0-1/Source/libcovis.a /usr/local/src/CoViS-0.0.0-1/Source/contrib/gnuplot_i/libcovis_contrib_gnuplot_i.a -lgl2ps
CMAKE_CXX_FLAGS:STRING=-I/usr/local/src/CoViS-0.0.0-1/Source -I/usr/include/opencv -I/usr/include/cairo
The only difference I can see is that the paths are absolute and not relative, but if he couldn't find the libs, he would say it...
There are two different issues there, the first of which is the simplest, you have used the wrong compiler options. The -L option tells the linker to also look in the directory when looking for a library. The -l tells it to link the specific library. To link you would then use:
g++ -o test test.o -L/path/to -lcovis
or
g++ -o test test.o -l/path/to/libcovis.a
To force static linking if the same library is present as a dynamic library in the same directory.
The second potential issue is that the order of static libraries in the linker command line does matter, so that might also be an issue if there is a dependency on different static libs.
g++ -o test tests.o -ldependent -lprovider
The linker will process the libraries in order as they are in the command line, and from each static lib it will only pull those symbols that are required (with as much information as the linker has at that time). In the command line above, the linker will extract from dependent the symbols it needs for test.o, and that might in turn add new undefined symbols to the program (the dependencies of dependent). When it processes provider it will fill in those symbols. If the order was reversed in the command line, the symbols that are required by dependent but not by test.o would not be added to the executable, as the linker does not know that those symbols will be needed when processing provider.
Should the arguments be like -L/path/to/ -lcovis?
Besides, object files should be placed before libs, for example
g++ obj1.o obj2.o -L/path/to/ -lcovis.
If you see the link succeeding in one context but not another, I suspect the problem may be caused by the order in which the link operation is executed as the linker will discard symbols in a library if they're not needed at the point in which the library is referenced.
Here is a link explaining: http://www.network-theory.co.uk/docs/gccintro/gccintro_18.html
I've run into similar situations in the past the linking order was found to be the cause of the problem.