Comment 0 for bug 1901966

I believe I'm having the problem described in #1846557 and #1848200. Those bugs were reported fixed in 8.1.1 but I'm observing them in 9.2 so I suspect a regression (in fact, if I read the notes correctly, the earlier reports were from another regression!).

I create a new EC2 server on AWS with Ubuntu Server 20.04 LTS (64-bit Arm) then perform the following installs (not sure what is needed or if something is missing):

```
sudo dpkg --add-architecture armhf
sudo apt update
sudo apt upgrade -y
sudo apt install -y build-essential vim binutils-arm-linux-gnueabi \
  gdb libc6:armhf libstdc++6:armhf
```

Then I create hello.s:

```
        .text
        .global _start
_start:
        MOV R7, #4
        MOV R0, #1
        LDR R1, =hello
        LDR R2, =hello_size
        SWI 0
        MOV R7, #1
        SWI 0

        .data
hello: .asciz "Hello world!\n"
        .equ hello_size, (.-hello)
```

Then I assemble, link, and run, all with success. Finally, I try to debug:

```
$ arm-linux-gnueabi-as -ggdb -mcpu=cortex-a57 -o out.o $@
$ arm-linux-gnueabi-ld out.o -dynamic-linker=/usr/lib/ld-linux-armhf.so.3 -o out
$ rm out.o
$ ./out
Hello world!
$ gdb out
GNU gdb (Ubuntu 9.2-0ubuntu1~20.04) 9.2
...
Reading symbols from out...
(gdb) b _start
Breakpoint 1 at 0x10074: file hello.s, line 4.
(gdb) run
Starting program: /home/ubuntu/280/out
```

At this point everything hangs until I press ^C:

```
^C
Program received signal SIGINT, Interrupt.
0x0000aaaaba072284 in ?? ()
(gdb) bt
#0 0x0000aaaaba072284 in ?? ()
#1 0x0000000000007232 in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)
(gdb) l
1 .text
2 .global _start
3 _start:
4 MOV R7, #4
5 MOV R0, #1
6 LDR R1, =hello
7 LDR R2, =hello_size
8 SWI 0
9 MOV R7, #1
10 SWI 0
(gdb) q
A debugging session is active.

 Inferior 1 [process 29234] will be killed.

Quit anyway? (y or n) y
$
```

It appears that gdb generally works and recognizes the executable, but breakpoints don't work. I'm new at Arm and don't have a lot of experience with assembly (at least not since the early 1970s), so it could easily be my problem but it seems suspiciously like an earlier problem and I think what I've done should work.