I am new to C++ compiling/linking.
I am trying to link all libraries statically with gcc, I tried using LDFLAGS=-static but did not work. Error message showed:
/bin/sh ./libtool --tag=CXX --mode=link /home/dizhang/lib/hdf5/bin/h5c++ -g -O2 -L/home/dizhang/lib/blitz/lib -L/home/dizhang/lib/libconfig/lib -o angora src/libangora.la -lblitz -lconfig++
libtool: link: /home/dizhang/lib/hdf5/bin/h5c++ -g -O2 -o angora -L/home/dizhang/lib/blitz/lib -L/home/dizhang/lib/libconfig/lib src/.libs/libangora.a -L/bgsys/drivers/V1R2M2/ppc64/comm/lib64 -L/bgsys/drivers/V1R2M2/ppc64/comm/lib -L/bgsys/drivers/V1R2M2/ppc64/spi/lib -lpthread -lm /home/dizhang/lib/blitz/lib/libblitz.a /bgsys/drivers/V1R2M2/ppc64/comm/lib/libmpichcxx-gcc.so /bgsys/drivers/toolchain/V1R2M2_base/gnu-linux/powerpc64-bgq-linux/lib/libstdc++.so /bgsys/drivers/V1R2M2/ppc64/comm/lib/libmpich-gcc.so /bgsys/drivers/V1R2M2/ppc64/comm/lib/libopa-gcc.so /bgsys/drivers/V1R2M2/ppc64/comm/lib/libmpl-gcc.so /home/dizhang/lib/libconfig/lib/libconfig++.a /bgsys/drivers/toolchain/V1R2M2_base-efix014/gnu-linux/powerpc64-bgq-linux/lib/libstdc++.so -Wl,-rpath -Wl,/bgsys/drivers/toolchain/V1R2M2_base-efix014/gnu-linux/powerpc64-bgq-linux/lib -Wl,-rpath -Wl,/bgsys/drivers/V1R2M2/ppc64/comm/lib -Wl,-rpath -Wl,/bgsys/drivers/toolchain/V1R2M2_base/gnu-linux/powerpc64-bgq-linux/lib -Wl,-rpath -Wl,/bgsys/drivers/toolchain/V1R2M2_base-efix014/gnu-linux/powerpc64-bgq-linux/lib -Wl,-rpath -Wl,/bgsys/drivers/V1R2M2/ppc64/comm/lib -Wl,-rpath -Wl,/bgsys/drivers/toolchain/V1R2M2_base/gnu-linux/powerpc64-bgq-linux/lib
/bgsys/drivers/toolchain/V1R2M2_base-efix014/gnu-linux/lib/gcc/powerpc64-bgq-linux/4.4.7/../../../../powerpc64-bgq-linux/bin/ld: attempted static link of dynamic object `/bgsys/drivers/V1R2M2/ppc64/comm/lib/libmpichcxx-gcc.so'
collect2: ld returned 1 exit status
I did some search and found that, telling Makefile -Wl -Bstatic may solve this problem, but how exactly I should change this in my Makefile?
I tried searching -Wl in Makefile but it was not in the text.
Thanks,
Di
Looks like you are trying to build HDF5 with MPI support on BGQ.
As long as you end up passing a ".so" version of a lib to gcc on BGQ -- you will see this error. You may need to check how you are passing MPI info to HDF5's configure script.
In my case (building another project that uses CMake) passing BGQ's MPI compiler wrappers to CMake always created a problem where it would try to link MPI using the shared libs instead of the static ones. To resolve this, I had to make sure to explicitly specify the ".a" variants of the MPI libs.
Related
I am working on a project which eventually requires me to link my code against my customized version of libc, libstdc++ and libgcc. Now I am learning what libraries are linked by default.
I tried to compile my project code with -nolibc and manually provide the needed libraries in the argument list.
g++ -fuse-ld=gold -O2 -o main -static -nolibc main.cpp -lgcc -lm -lc
I got the following error, showing that I missed some libraries.
/usr/lib/gcc/x86_64-linux-gnu/9/libgcc_eh.a(unwind-dw2-fde-dip.o):function _Unwind_Find_FDE: error: undefined reference to 'dl_iterate_phdr'
Which library is missing here?
I am trying to cross compile my application for a arm based system.
I have 2 libraries compiled in the following way:
$ gcc -shared --sysroot=$DIR_PATH -o $LIBPATH/libfoo.so foo.o
$ gcc -shared --sysroot=$DIR_PATH -o $LIBPATH/libbar.so bar.o
A third library is compiled:
gcc -shared -o $LIBPATH/libfoobar.so --sysroot=$DIR_PATH -L$LIBPATH -Wl,rpath=$RUN_TIME_PATH foobar.o -lfoo -lbar
Then finally I compile a binary:
gcc -o app --sysroot=$DIR_PATH -L$LIBPATH -Wl,rpath=$RUN_TIME_PATH app.o -lfoobar
However when compiling app I get
warning: libfoo.so, needed by libfoobar.so, not found (try using -rpath or -rpath-link)
I believe you need to use -Wl,-rpath-link=$LIBPATH to tell the linker where to look to resolve runtime library references during the link operation.
More info can be found in the ld documentation: https://sourceware.org/binutils/docs-2.37/ld/Options.html
Im developing an android app thats loading two shared libraries. One is external, its called libpcan.so . Usually its build to libpcan.so.0.6, this somehow cant be used by my android, i so changed the gcc flags compiling it from:
arm-linux-androideabi-gcc src/libpcan.c -fPIC -shared -O2 -Wall -Wl,-soname,-libpcan.so.0 -lc -I. -I../driver -DNO_RT -o -libpcan.so.0.6
ln -sf libpcan.so.0.6 libpcan.so
to
arm-linux-androideabi-gcc src/libpcan.c -fPIC -shared -O2 -Wall -lc -I. -I../driver -DNO_RT -o -libpcan.so
This .so has the same size as the so.0.6 so i assume it worked fine.
My own c-code is getting compiled with
arm-linux-androideabi -shared src/receivetest.c src/common.c -I. -I../lib -I../driver -L../lib -L/lib -L/usr/lib -L/usr/local/lib -o libreceivetest.so
I load both of these files, so the libpcan.so and the libreceivetest.so to my app
static {
System.loadLibrary("pcan");
System.loadLibrary("receivetest");
}
When I'm trying to launch that app i get the error message:
07-14 11:12:43.812: E/AndroidRuntime(753): java.lang.ExceptionInInitializerError
07-14 11:12:43.812: E/AndroidRuntime(753): Caused by: java.lang.UnsatisfiedLinkError: Cannot load library: reloc_library[1306]: 36 cannot locate 'CAN_Open'...
My receivetest is using that function, but since it declared in the libpcan.so and im also loading that library, i don't know where that error could come from.
I'd just guess its an error in my clags, since I'm new to building .so files via using gcc in the shell i don't really understand all the flags im using.
It's quite long since i solved this. But I haven't ever marked this question as solved.
Thanks to jww for reminding me.
As I've said in the comment to my question, the link to the function CAN_Open was missing due to a missing parameter at compiling the .so-file. The function CAN_Open is a part of the libpcan.so and by skipping the link to that file the CAN_Open function just never made it into the receivetest.so .
I've been trying to find the proper .a's and related flags for statically linking an app or SO under Linux. I know -static exists, but I can't use it as there's one specific SO I must link to.
To put it another way, I'm looking for the appropriate flags to statically link everything, except for a specific SO.
Thanks.
At my workplace we use -Bstatic and -Bdynamic but they are options to the linker ld. You can specify them with gcc using the -Wl option.
g++ -o app -Wl,-Bstatic -llib1 -llib2 -llib3 -Wl,-Bdynamic -llib4 app.o
Above shows command line for linking with lib1, lib2, and lib3 as static libraries and lib4 as a shared object library.
I'm currently trying to compile a dynamically linked library (for a plugin system) using Windows and MinGW.
I compile each objects using this command line :
mingw-g++ -fPIC test.cpp
And the library using this line:
mingw-g++ -rdynamic -shared -Wl,-soname,test.so.1 -o test.so test.o
It doesn't work at all (using GCC with Linux, a similar line works though) : fPIC and rdynamic are ignored for some reason.
And while trying to make the library, it fails because the compiler try to link it with objects that are supposed to be resolved as I dynamically link it with the main binary.
So how do you compile this using MinGW?
Thanks :) !
-fPIC and -rdynamic are ignored because they are unused for Windows.
Also, .so is not the correct output extension for libraries on Windows.
To make a shared library for/on windows with GCC:
mingw-g++ -c file.cpp -o file.o
mingw-g++ -shared -Wl,--out-implib,libfile.a -o file.dll file.o
No more, no less.
And, documentation is always lovely to have: http://www.mingw.org/wiki/sampleDLL