port-sparc/57337: gdb completely broken on sparc

[uwe%stderr.spb.ru@localhost]

>Number:         57337
>Category:       port-sparc
>Synopsis:       gdb completely broken on sparc
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    port-sparc-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Apr 09 14:05:00 +0000 2023
>Originator:     Valery Ushakov
>Release:        NetBSD 10
>Organization:
>Environment:
NetBSD krups 10.99.2 NetBSD 10.99.2 (KRUPS) #0: Wed Dec 28 02:08:31 MSK 2022  uwe@majava:/home/uwe/work/netbsd/cvs/src/sys/arch/sparc/compile/KRUPS sparc
>Description:
Gdb seems to be completely broken in current.  Unable to get
debuggee registers.

>How-To-Repeat:
$ gdb -q ./hello
Reading symbols from ./hello...
(gdb) b main
Breakpoint 1 at 0x10748: file hello.c, line 6.
(gdb) r
Starting program: /root/hello 

Breakpoint 1, main (
    argc=<error reading variable: Cannot access memory at address 0xf50b1044>, 
    argv=<error reading variable: Cannot access memory at address 0xf50b1048>)
    at hello.c:6
6               printf("%d\n", argc);
(gdb) l
1       #include <stdio.h>
2       
3       int
4       main(int argc, char **argv)
5       {
6               printf("%d\n", argc);
7               return 0;
8       }
(gdb) i r
...
l0             0x65e5e8            6677992
l1             0x65e5e8            6677992
l2             0x65e5e8            6677992
l3             0x65e5e8            6677992
l4             0x65e5e8            6677992
l5             0x65e5e8            6677992
l6             0x65e5e8            6677992
l7             0x65e5e8            6677992
i0             0x65e5e8            6677992
i1             0x65e5e8            6677992
i2             0x65e5e8            6677992
i3             0x65e5e8            6677992
i4             0x65e5e8            6677992
i5             0x65e5e8            6677992
fp             0x65e5e8            0x65e5e8
i7             0x65e5e8            6677992
...

>Fix: