[RFC] i386 PLT stub unwinder

[Tom Tromey]

>>>>> "Jan" == Jan Kratochvil <jan.kratochvil@redhat.com> writes:

Jan> On Mon, 13 Jun 2011 17:55:56 +0200, Mark Kettenis wrote:
>> Jan's mail about DWARF CFI for PLT stubs prompted me to write an
>> undinder for the PLT stubs as defined by the i386 ABI.  With this
>> change I can step through the PLT stubs and always have a proper
>> backtrace.

Jan> I do not think GDB is the right place to fix it, it should be fixed
Jan> by proper .eh_Frame as this problem affects all the tools trying to
Jan> unwind such as also oprofile, systemtap etc.

I agree, but I think also doing it in GDB is harmless, at least provided
that the new unwinder is only applied when the PLT stubs are missing the
needed info.  That way, when ld is fixed, GDB will automatically start
doing the right thing.

Tom