launchpad-users team mailing list archive

[Andrew Kelley <superjoe30@xxxxxxxxx>]

On Tue, Nov 19, 2013 at 7:34 PM, Frank Trampe <frank.trampe@xxxxxxxxx>wrote:

> As you're running it, gcc is trying to link statically (against
> libgroove.a), so the contents of libgroove.so don't mean much. Are you
> trying to link dynamically?
>

Yes I am trying to link dynamically. I'm confused - I thought using -l was
dynamic linking and specifying -static and supplying .a files does static
linking. Furthermore, when I link the exact same test.c file with the same
gcc args against a libgroove installation that was built from source rather
than from the PPA, it successfully links and runs. What could explain this
behavior?


>
> Running nm -g on your static library shows that it includes undefined
> static symbols for the functions that you list. If you link against those
> libraries (libav and libsdl) when building test.c, this ought to work.
>
>
>
> On Tue, Nov 19, 2013 at 11:21 AM, Andrew Kelley <superjoe30@xxxxxxxxx>wrote:
>
>> Hello -
>>
>> I just added a library to my ppa:
>> https://launchpad.net/~andrewrk/+archive/libgroove
>> so far so good, it installs on my system. But when I compile a program
>> against it, I get linker errors - undefined symbols from libraries that my
>> library depends on. This does not happen when I manually build from source.
>>
>> Any suggestions?
>>
>> Here are some more details.
>>
>> The problem:
>>
>> andy@andy-bx:~/tmp$ c99 -o test test.c -lgroove
>> /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../lib/libgroove.a(file.c.o): In function `cleanup_save':
>>
>> (.text+0x29): undefined reference to `av_free_packet'
>> /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../lib/libgroove.a(file.c.o): In function `cleanup_save':
>>
>> (.text+0x39): undefined reference to `avio_closep'
>> /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../lib/libgroove.a(file.c.o): In function `cleanup_save':
>>
>> (.text+0x54): undefined reference to `avformat_free_context'
>> /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../lib/libgroove.a(file.c.o): In function `cleanup_save':
>>
>> (.text+0xa1): undefined reference to `av_log'
>> /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../lib/libgroove.a(file.c.o): In function `groove_file_close':
>>
>> (.text+0xe6): undefined reference to `av_free_packet'
>> /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../lib/libgroove.a(file.c.o): In function `groove_file_close':
>>
>> (.text+0x105): undefined reference to `avcodec_close'
>> /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../lib/libgroove.a(file.c.o): In function `groove_file_close':
>>
>> (.text+0x12b): undefined reference to `avformat_close_input'
>> /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../lib/libgroove.a(file.c.o): In function `groove_file_close':
>>
>> (.text+0x139): undefined reference to `SDL_DestroyMutex'
>> /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../lib/libgroove.a(file.c.o): In function `groove_file_open':
>>
>> (.text+0x16f): undefined reference to `av_mallocz'
>> /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../lib/libgroove.a(file.c.o): In function `groove_file_open':
>>
>> (.text+0x18f): undefined reference to `SDL_CreateMutex'
>> /usr/lib/gcc/x86_64-linux-gnu/4.8/../../../../lib/libgroove.a(file.c.o): In function `groove_file_open':
>>
>> (.text+0x1a1): undefined reference to `avformat_alloc_context'
>> ...(snip)...
>>
>>
>> libav is a static dependency of libgroove, and SDL2 is a dynamic dependency.
>> test.c uses only libgroove, it does not depend on libav or SDL2.
>>
>>
>> andy@andy-bx:~$ ldd /usr/lib/libgroove.so.2.0.2
>> 	linux-vdso.so.1 =>  (0x00007fff499c9000)
>> 	libbz2.so.1.0 => /lib/x86_64-linux-gnu/libbz2.so.1.0 (0x00007fc04ecde000)
>>
>> 	libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007fc04eac5000)
>> 	libmp3lame.so.0 => /usr/lib/x86_64-linux-gnu/libmp3lame.so.0 (0x00007fc04e837000)
>>
>> 	libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007fc04e61a000)
>> 	libSDL2-2.0.so.0 => /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0 (0x00007fc04e346000)
>>
>> 	libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fc04df7d000)
>> 	libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007fc04dc79000)
>>
>>
>> 	/lib64/ld-linux-x86-64.so.2 (0x00007fc04ff2a000)
>> 	libasound.so.2 => /usr/lib/x86_64-linux-gnu/libasound.so.2 (0x00007fc04d989000)
>> 	libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007fc04d784000)
>>
>>
>>
>> 	libpulse-simple.so.0 => /usr/lib/x86_64-linux-gnu/libpulse-simple.so.0 (0x00007fc04d580000)
>> 	libpulse.so.0 => /usr/lib/x86_64-linux-gnu/libpulse.so.0 (0x00007fc04d337000)
>>
>> 	libX11.so.6 => /usr/lib/x86_64-linux-gnu/libX11.so.6 (0x00007fc04d001000)
>> 	libXext.so.6 => /usr/lib/x86_64-linux-gnu/libXext.so.6 (0x00007fc04cdef000)
>>
>> 	libXcursor.so.1 => /usr/lib/x86_64-linux-gnu/libXcursor.so.1 (0x00007fc04cbe5000)
>> 	libXinerama.so.1 => /usr/lib/x86_64-linux-gnu/libXinerama.so.1 (0x00007fc04c9e1000)
>>
>> 	libXi.so.6 => /usr/lib/x86_64-linux-gnu/libXi.so.6 (0x00007fc04c7d1000)
>> 	libXrandr.so.2 => /usr/lib/x86_64-linux-gnu/libXrandr.so.2 (0x00007fc04c5c7000)
>>
>> 	libXss.so.1 => /usr/lib/x86_64-linux-gnu/libXss.so.1 (0x00007fc04c3c2000)
>> 	libXxf86vm.so.1 => /usr/lib/x86_64-linux-gnu/libXxf86vm.so.1 (0x00007fc04c1bc000)
>>
>> 	librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007fc04bfb4000)
>> 	libpulsecommon-4.0.so => /usr/lib/x86_64-linux-gnu/pulseaudio/libpulsecommon-4.0.so (0x00007fc04bd4c000)
>>
>>
>>
>> 	libjson-c.so.2 => /lib/x86_64-linux-gnu/libjson-c.so.2 (0x00007fc04bb42000)
>> 	libdbus-1.so.3 => /lib/x86_64-linux-gnu/libdbus-1.so.3 (0x00007fc04b8fc000)
>>
>> 	libxcb.so.1 => /usr/lib/x86_64-linux-gnu/libxcb.so.1 (0x00007fc04b6de000)
>> 	libXrender.so.1 => /usr/lib/x86_64-linux-gnu/libXrender.so.1 (0x00007fc04b4d4000)
>>
>> 	libXfixes.so.3 => /usr/lib/x86_64-linux-gnu/libXfixes.so.3 (0x00007fc04b2cd000)
>> 	libwrap.so.0 => /lib/x86_64-linux-gnu/libwrap.so.0 (0x00007fc04b0c3000)
>>
>> 	libsndfile.so.1 => /usr/lib/x86_64-linux-gnu/libsndfile.so.1 (0x00007fc04ae5a000)
>> 	libasyncns.so.0 => /usr/lib/x86_64-linux-gnu/libasyncns.so.0 (0x00007fc04ac54000)
>>
>> 	libXau.so.6 => /usr/lib/x86_64-linux-gnu/libXau.so.6 (0x00007fc04aa50000)
>> 	libXdmcp.so.6 => /usr/lib/x86_64-linux-gnu/libXdmcp.so.6 (0x00007fc04a849000)
>>
>> 	libnsl.so.1 => /lib/x86_64-linux-gnu/libnsl.so.1 (0x00007fc04a62f000)
>> 	libFLAC.so.8 => /usr/lib/x86_64-linux-gnu/libFLAC.so.8 (0x00007fc04a3fe000)
>>
>> 	libvorbisenc.so.2 => /usr/lib/x86_64-linux-gnu/libvorbisenc.so.2 (0x00007fc049f2e000)
>> 	libvorbis.so.0 => /usr/lib/x86_64-linux-gnu/libvorbis.so.0 (0x00007fc049d01000)
>>
>> 	libogg.so.0 => /usr/lib/x86_64-linux-gnu/libogg.so.0 (0x00007fc049af8000)
>> 	libresolv.so.2 => /lib/x86_64-linux-gnu/libresolv.so.2 (0x00007fc0498dd000)
>>
>>
>> # libav is not on this list because libgroove depends statically upon it
>>
>>
>>
>> here's the difference in linker steps for libgroove.so between the working manual build and the not-working PPA build:
>>
>> # ppa link step (broken):
>>
>> /usr/bin/cc  -fPIC -g -O2 -fstack-protector --param=ssp-buffer-size=4 -Wformat -Werror=format-security -D_FORTIFY_SOURCE=2  -O2 -g -DNDEBUG -Wl,-Bsymbolic  -Wl,-z,relro -shared -Wl,-soname,libgroove.so.2 -o libgroove.so.2.0.2 CMakeFiles/groove.dir/src/queue.c.o CMakeFiles/groove.dir/src/loudness_detector.c.o CMakeFiles/groove.dir/src/buffer.c.o CMakeFiles/groove.dir/src/encoder.c.o CMakeFiles/groove.dir/src/file.c.o CMakeFiles/groove.dir/src/playlist.c.o CMakeFiles/groove.dir/src/global.c.o CMakeFiles/groove.dir/src/player.c.o deps/libav/install/lib/libavfilter.a deps/libav/install/lib/libavformat.a deps/libav/install/lib/libavcodec.a deps/libav/install/lib/libavresample.a deps/libav/install/lib/libswscale.a deps/libav/install/lib/libavutil.a -lbz2 -lz -lmp3lame -lpthread -Wl,-Bstatic -lSDL2main -Wl,-Bdynamic -lSDL2 -lpthread -Wl,-Bstatic -lebur128 -lSDL2main -Wl,-Bdynamic -lSDL2 -Wl,-Bstatic -lebur128 -Wl,-Bdynamic
>>
>>
>>
>>
>> # see full build log: https://launchpadlibrarian.net/156927161/buildlog_ubuntu-saucy-amd64.libgroove_2.0.2-2_UPLOADING.txt.gz
>>
>>
>>
>>
>>
>> # build manually from source link step (works):
>>
>>
>> /usr/bin/cc  -fPIC  -Wl,-Bsymbolic   -shared -Wl,-soname,libgroove.so.2 -o libgroove.so.2.0.0 CMakeFiles/groove.dir/src/global.c.o CMakeFiles/groove.dir/src/loudness_detector.c.o CMakeFiles/groove.dir/src/playlist.c.o CMakeFiles/groove.dir/src/buffer.c.o CMakeFiles/groove.dir/src/encoder.c.o CMakeFiles/groove.dir/src/queue.c.o CMakeFiles/groove.dir/src/file.c.o CMakeFiles/groove.dir/src/player.c.o deps/libav/install/lib/libavfilter.a deps/libav/install/lib/libavformat.a deps/libav/install/lib/libavcodec.a deps/libav/install/lib/libavresample.a deps/libav/install/lib/libswscale.a deps/libav/install/lib/libavutil.a -lbz2 -lz -lmp3lame -lpthread -Wl,-Bstatic -lSDL2main -Wl,-Bdynamic -lSDL2 -lpthread deps/ebur128/libebur128.a -Wl,-Bstatic -lSDL2main -Wl,-Bdynamic -lSDL2
>>
>>
>>
>>
>> _______________________________________________
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>>
>