[Bug backtrace/15032] GNU/Linux backtrace fails to use eh_frameinformation when built with --enable-64-bit-bfd

["jkain at nvidia dot com" <sourceware-bugzilla at sourceware dot org>]

http://sourceware.org/bugzilla/show_bug.cgi?id=15032

--- Comment #4 from Joseph Kain <jkain at nvidia dot com> 2013-01-18 21:25:41 UTC ---
I stepped through read_encoded_value again looking for any relocation.  Note
the values have changed due to changes to the inferior.

When base is computed in the DW_EH_PE_pcrel case:

* bfd_get_section_vma => 0xbfd80.  This matches the value of the VMA of the
.eh_frame section as reported by objdump -x.

* (buf - unit->dwarf_frame_buffer) => 0x20.  I think this seems reasonable for
the first FDE.

* base = 0xbfda0.


When the final value is computed in the DW_EH_PE_udata4 case:

* bfd_get_32() => 0xfff7bbe0.  bfd_read_32() reads from offset 0xbfda0 from the
unit.  I confirmed that buf points to offset 0xbfda0 in the correct .so via
/proc/<pid>/maps.  I also confirmed with a hex editor that the value 0xfff7bbe0
appears at offset 0xbfda0 in the .so's image on disk.  I don't think there was
any relocation done.

* base + bfd_get_32 (...) => 0x10003b980.

So I don't think there was any relocation done.  I also don't see any
relocation entries in the .so for the offset 0xbfda0?  Should there be one?

-- 
Configure bugmail: http://sourceware.org/bugzilla/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are on the CC list for the bug.