>    The segment registers have the same problem, is the attached ok? 6.1? 
>    With it applied I get test results that approach i386.
> 
>    2004-02-29  Andrew Cagney  <cagney@redhat.com>
> 
> 	   * amd64-nat.c (amd64_collect_native_gregset): Zero-extend the
> 	   32-bit segment registers.
> 
> OK.  Feel free to add the segment registers to enum i386_regnum and
> use <= I386_GS_REGNUM instead of < I386_ST0_REGNUM though.

Attatched is what I've committed (mainline and, in two ticks, 6.1).

A GDB, with that PC==0 hack to work around the GLIBC problems applied, 
gets these unexpected failures:

FAIL: gdb.base/gcore.exp: where in corefile (pattern 1)
FAIL: gdb.base/gcore.exp: corefile restored general registers
FAIL: gdb.base/gcore.exp: corefile restored all registers
FAIL: gdb.base/gcore.exp: capture_command_output failed on print 
array_func::local_array.
FAIL: gdb.base/gcore.exp: corefile restored stack array
FAIL: gdb.base/gcore.exp: corefile restored backtrace
FAIL: gdb.base/interrupt.exp: echo data (timeout)
FAIL: gdb.base/signals.exp: continue to func1 (probably kernel bug)
FAIL: gdb.base/signals.exp: continue to handler (the program exited)
FAIL: gdb.threads/gcore-thread.exp: corefile contains at least two threads
FAIL: gdb.threads/gcore-thread.exp: a corefile thread is executing thread2
FAIL: gdb.threads/gcore-thread.exp: thread2 is current thread in corefile
                 === gdb Summary ===

# of expected passes            9860
# of unexpected failures        12
# of unexpected successes       1
# of expected failures          47
# of unknown successes          12
# of known failures             33
# of untested testcases         3
# of unsupported tests          1

not bad, eh :-)

Andrew