Comment 10 for bug 1248289

Revision history for this message
mbel (mbel) wrote :

looks like this issue is rather tricky. adding libunwind to build dependecies actually gives nothing, there is still no dwarf support. Digging deeper I found that following test, which detects libunwind support for perf is not passed:

"gcc -o test-libunwind test-libunwind.c -lunwind -lunwind-x86 -lelf" fails with
/usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_stream_buffer_decode'
/usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_index_uncompressed_size'
/usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_index_end'
/usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_index_buffer_decode'
/usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_stream_footer_decode'
/usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_index_size'
collect2: error: ld returned 1 exit status

adding -llzma to the test above doesn't solve the problem. During further investigation I found that there are problem with libunwind8-dev - its libraries lacks dependant libs. I filed bug on libunwind and proposed solution for x86 platform. Link to the bug is https://bugs.launchpad.net/ubuntu/+source/libunwind/+bug/1336912