The problem is that when the library was built the CRC of the debug symbols file gets planted in the main library file. OProfile very sensibly checks that the CRC of the debug file matches that stored in the actual library and ignores it if it doesn't.
GDB may well work and having hacked oprofile to ignore the embedded CRC in library it *seems* to give correct results. Of course it's hard to be sure because the -dbg symbols look as though they were created at a different time to the actual library. If I look at the opreport -V bfd output on the same library on my Gentoo system (where I know the striped symbol-file was created at the same time as the library) I can see the CRC's match and everything is fine. Picking a random example (libc) I see the following when running "opreport -V bfd": looking for debugging file libc-2.7.so with crc32 = 9587b62d separate_debug_file_exists: /lib/.debug/libc-2.7.so give img_path/lib/.debug/libc-2.7.so separate_debug_file_exists: /usr/lib/debug/lib/libc-2.7.so give img_path/usr/lib/debug/lib/libc-2.7.so found /usr/lib/debug/lib/libc-2.7.so with crc32 = 9587b62d now loading: /usr/lib/debug/lib/libc-2.7.so And you can see the CRC of the debug libc matches so we can be confident of the results offered by oprofile (and gdb for that matter). As I stated in the original report this may be an artifact of the build process that creates packages however I don't really have an understanding of the Ubuntu build farm. Perhaps there is someone on the infrastructure team that could give some input. The versions of libcairo2 involved are: 11:05 r...@vnms/x86_64 [vnms] >dpkg --status libcairo2 libcairo2-dbg Package: libcairo2 Status: deinstall ok installed Priority: optional Section: libs Installed-Size: 828 Maintainer: Ubuntu Core Developers <ubuntu-devel-disc...@lists.ubuntu.com> Architecture: amd64 Source: cairo Version: 1.6.0-0ubuntu2 Replaces: libcairo0.5.1, libcairo0.6.0, libcairo0.9.0, libcairo1 Provides: libcairo Depends: libc6 (>= 2.4), libfontconfig1 (>= 2.4.0), libfreetype6 (>= 2.3.5), libgcc1 (>= 1:4.1.1-21), libpixman-1-0 (>= 0.10.0), libpng12-0 (>= 1.2.13-4), libstdc++6, libx11-6, libxrender1, zlib1g (>= 1:1.2.3.3.dfsg-1) Conflicts: libcairo1 Description: The Cairo 2D vector graphics library Cairo is a multi-platform library providing anti-aliased vector-based rendering for multiple target backends. Paths consist of line segments and cubic splines and can be rendered at any width with various join and cap styles. All colors may be specified with optional translucence (opacity/alpha) and combined using the extended Porter/Duff compositing algebra as found in the X Render Extension. . Cairo exports a stateful rendering API similar in spirit to the path construction, text, and painting operators of PostScript, (with the significant addition of translucence in the imaging model). When complete, the API is intended to support the complete imaging model of PDF 1.4. . This package contains the shared libraries. Homepage: http://cairographics.org/ Original-Maintainer: Dave Beckett <daj...@debian.org> Package: libcairo2-dbg Status: install ok installed Priority: extra Section: libdevel Installed-Size: 1648 Maintainer: Ubuntu Core Developers <ubuntu-devel-disc...@lists.ubuntu.com> Architecture: amd64 Source: cairo Version: 1.6.0-0ubuntu2 Depends: libcairo2 (= 1.6.0-0ubuntu2) Description: The Cairo 2D vector graphics library (debugging symbols) Debugging symbols for the Cairo 2D vector graphics library. This is needed to debug programs linked against libcairo2. Homepage: http://cairographics.org/ Original-Maintainer: Dave Beckett <daj...@debian.org> Hey the worst case scenario is that some Black Hat attacker has built their own version of libcairo, somehow subverted the signing keys and penetrated the Ubuntu servers and uploaded a compromised library but never bother with the -dbg .deb package. It's fairly unlikely but its the only explanation for mismatched CRC's I can think of at the moment. -- libcairo2-dbg CRC doesn't match symbol (I suspect this is more widespread) https://bugs.launchpad.net/bugs/415424 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
