Linux dump_syms should look for debug files using the GDB "debug link" method

[GoogleCodeExporter]

Even without specifying the paths to search for the debug file, for a given 
/path/to/file with file.debug in the .gnu_debuglink section, gdb will search:
- /path/to/file.debug
- /path/to/.debug/file.debug
- /usr/lib/debug/path/to/file.debug

dump_syms should do the same.

Note the debug link could be "file", so we should avoid searching /path/to/file 
again.

Original issue reported on code.google.com by [email protected] on 10 Feb 2015 at 2:47

[GoogleCodeExporter]

It might be nicer to support finding debug files with build-id.
(https://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html)

For example, libdbus on Ubuntu uses build-id to provide debug files.
(http://packages.ubuntu.com/trusty/amd64/dbus-1-dbg/filelist)

Original comment by [email protected] on 10 Feb 2015 at 4:50

[GoogleCodeExporter]

Sure, we can do both.

Original comment by [email protected] on 10 Feb 2015 at 5:52

[GoogleCodeExporter]

I have a patch to do the "debug link" method: 
https://breakpad.appspot.com/7784002/ but I want to look into test coverage 
first so I don't accidentally break something while shuffling code around.

Original comment by [email protected] on 11 Feb 2015 at 12:49

• Added labels: OpSys-Linux
• Removed labels: OpSys-OSX