So the issue is: if there is a .gnu_debugaltlink GDB will try to load that file and throw an error if it can't. That path is absolute and GDB does _not_ look for that path/file anywhere else, not even inside 'debug-file-directory'.
GDB seems to only look at section .gnu_debugaltlink in debug/.build- id/nn/nnnnnn.debug, it does not seem to use that section from the binary at all. Due to that, another workaround is to modify that section to point to the 'right' place: 1) use objcopy to dump .gnu_debugaltlink from debug/.build-id/nn/nnnnnn.debug into a file 2) use sed to modify the path in the dump file 3) use objcopy to update .gnu_debugaltlink section in debug/.build-id/nn/nnnnnn.debug As in: $ objcopy --dump-section .gnu_debugaltlink=altlink /tmp/dbgsym/usr/lib/debug/.build-id/76/e9f820204912084fd156c593b2c92f1a4b51f1.debug $ sed -i 's:^:/tmp/dbgsym:' altlink $ objcopy --update-section .gnu_debugaltlink=altlink /tmp/dbgsym/usr/lib/debug/.build-id/76/e9f820204912084fd156c593b2c92f1a4b51f1.debug -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to apport in Ubuntu. https://bugs.launchpad.net/bugs/1818918 Title: gdb doesn't search in debug-file-directory for .gnu_debugaltlink Status in Apport: Fix Released Status in apport package in Ubuntu: New Status in gdb package in Ubuntu: Confirmed Bug description: As far as I can tell gdb version 8.2.90 isn't searching the debug- file-directory, which I set, for the '.gnu_debugaltlink' which is in the debug symbols. Here's the error I'm seeing: Type "apropos word" to search for commands related to "word". Reading symbols from /srv/vms/apport-sandbox-dir/Ubuntu 19.04/amd64/report-sandbox//usr/bin/gnome-calculator... Reading symbols from /srv/vms/apport-sandbox-dir/Ubuntu 19.04/amd64/report-sandbox/usr/lib/debug/.build-id/95/59c4c5ee30eb66d47bb9bd64784a69c9a6de6b.debug... could not find '.gnu_debugaltlink' file for /srv/vms/apport-sandbox-dir/Ubuntu 19.04/amd64/report-sandbox/usr/lib/debug/.build-id/95/59c4c5ee30eb66d47bb9bd64784a69c9a6de6b.debug (No debugging symbols found in /srv/vms/apport-sandbox-dir/Ubuntu 19.04/amd64/report-sandbox/usr/lib/debug/.build-id/95/59c4c5ee30eb66d47bb9bd64784a69c9a6de6b.debug) Here's part of an strace of what's going on behind the scenes: lstat("/srv/vms/apport-sandbox-dir/Ubuntu 19.04/amd64/report-sandbox/usr/lib/debug/.build-id/95/59c4c5ee30eb66d47bb9bd64784a69c9a6de6b.debug", {st_mode=S_IFREG|0644, st_size=839744, ...}) = 0 openat(AT_FDCWD, "/usr/lib/debug/.dwz/x86_64-linux-gnu/gnome-calculator.debug", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) This is the only time "/usr/lib/debug" is searched, generally "/srv/vms/apport-sandbox-dir/Ubuntu 19.04/amd64/report- sandbox/usr/lib/debug/" is used. I'll attach the full strace though. For completeness here's the gdb command I'm using: Calling gdb command: '/srv/vms/apport-sandbox-dir/Ubuntu 19.04/amd64 /report-sandbox/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2' '/srv/vms /apport-sandbox-dir/Ubuntu 19.04/amd64/report-sandbox/usr/bin/gdb' --ex 'set debug-file-directory /srv/vms/apport-sandbox-dir/Ubuntu 19.04/amd64/report-sandbox/usr/lib/debug' --ex 'set solib-absolute- prefix /srv/vms/apport-sandbox-dir/Ubuntu 19.04/amd64/report-sandbox' --ex 'add-auto-load-safe-path /srv/vms/apport-sandbox-dir/Ubuntu 19.04/amd64/report-sandbox' --ex 'set solib-search-path /srv/vms /apport-sandbox-dir/Ubuntu 19.04/amd64/report-sandbox/lib/x86_64 -linux-gnu' --ex 'set data-directory /srv/vms/apport-sandbox- dir/Ubuntu 19.04/amd64/report-sandbox/usr/share/gdb' --ex 'file "/srv/vms/apport-sandbox-dir/Ubuntu 19.04/amd64/report- sandbox//usr/bin/gnome-calculator"' --ex 'core-file /tmp/apport_core_1b6dn6np' To manage notifications about this bug go to: https://bugs.launchpad.net/apport/+bug/1818918/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
