I know this question has been asked a few times, but none of the solutions have worked for me. I have a statically linked library that I would like to use with a JNI layer with versions pre Java 8. Based on my reading of "how to link static library into dynamic library in gcc", it seems possible. Here is my command line:
/usr/bin/g++ -shared -std=c++0x -D__extern_always_inline=inline -Wall -pedantic -O3 -fomit-frame-pointer -fno-strict-aliasing -D_FILE_OFFSET_BITS=64 -DNDEBUG -fPIC -Wl,--whole-archive target/vw_jni.a -o target/vw_jni.lib
This is based on writing a JNI layer to the Vowpal Wabbit library.
At this point in the build process I have statically created a file called target/vw_jni.a through static linking
target/vw_jni.a: In function `_fini':
(.fini+0x0): multiple definition of `_fini'
/usr/lib/gcc/x86_64-linux-gnu/4.9/../../../x86_64-linux-gnu/crti.o:(.fini+0x0): first defined here
target/vw_jni.a: In function `data_start':
(.data+0x8): multiple definition of `__dso_handle'
/usr/lib/gcc/x86_64-linux-gnu/4.9/crtbeginS.o:(.data.rel.local+0x0): first defined here
target/vw_jni.a: In function `_init':
(.init+0x0): multiple definition of `_init'
/usr/lib/gcc/x86_64-linux-gnu/4.9/../../../x86_64-linux-gnu/crti.o:(.init+0x0): first defined here
/usr/lib/x86_64-linux-gnu/libc_nonshared.a(elf-init.oS): In function `__libc_csu_init':
(.text+0x0): multiple definition of `__libc_csu_init'
target/vw_jni.a:(.text+0x1cea20): first defined here
/usr/lib/x86_64-linux-gnu/libc_nonshared.a(elf-init.oS): In function `__libc_csu_fini':
(.text+0x70): multiple definition of `__libc_csu_fini'
target/vw_jni.a:(.text+0x1ceab0): first defined here
/usr/lib/gcc/x86_64-linux-gnu/4.9/crtendS.o:(.tm_clone_table+0x0): multiple definition of `__TMC_END__'
target/vw_jni.a:(.data+0x2630): first defined here
/usr/bin/ld: target/vw_jni.a: .preinit_array section is not allowed in DSO
/usr/bin/ld: failed to set dynamic section sizes: Nonrepresentable section on output
collect2: error: ld returned 1 exit status
I'm not sure what this means and when I search around for it find results such as "C program no longer compiles in Ubuntu" that seem to suggest that I forgot a -o flag, but I know I have not.
- Is what I'm trying to do possible?
- What am I doing wrong?
I'm doing this on a Docker instance obtained through docker pull ubuntu:14.04
UPDATE:
I'm able to get rid of a few of the errors with the following command line
/usr/bin/g++ -shared -std=c++0x -D__extern_always_inline=inline -Wall -pedantic -O3 -fomit-frame-pointer -fno-strict-aliasing -D_FILE_OFFSET_BITS=64 -DNDEBUG -fPIC -nostdlib -Wl,--whole-archive target/vw_jni.a -o target/vw_jni.lib
This generates the following output
/usr/bin/ld: warning: Cannot create .note.gnu.build-id section, --build-id ignored.
/usr/bin/ld: target/vw_jni.a: .preinit_array section is not allowed in DSO
/usr/bin/ld: failed to set dynamic section sizes: Nonrepresentable section on output
collect2: error: ld returned 1 exit status
The reason I think this works is that by excluding the standard lib I don't have the redefinitions. I'm not sure where to go from here though.