Re: GDB single-step fails on alpha (Re: CVS commit: src/share/mk)

[Rin Okuyama <rokuyama%rk.phys.keio.ac.jp@localhost>]

On 2016/10/29 4:59, Martin Husemann wrote:
> I am not sure what I am doing wrong but with my build (including your patch)
> I get:
>
> [/tmp] martin@gemini > gdb pwd
> GNU gdb (GDB) 7.12
> Copyright (C) 2016 Free Software Foundation, Inc.
> ..
> For help, type "help".
> Type "apropos word" to search for commands related to "word"...
> Reading symbols from pwd...Reading symbols from /usr/libdata/debug//bin/pwd.debug...done.
> done.
> (gdb) break main
> Breakpoint 1 at 0x1060: file /ssd/src/bin/pwd/pwd.c, line 71.
> (gdb) run
> Starting program: /bin/pwd
> /tmp
> [Inferior 1 (process 34) exited normally]
>
>
> Does that work for you?

I understand the situation. That does not work also for me, regardless
of whether the patch is applied or not. It seems a bug related to
separate debugging symbols. Actually, the patched version of GDB works
for binaries with debugging symbols:

  % cc -g -O0 hello.c -o hello
  % gdb ./hello
  GNU gdb (GDB) 7.12
  ...
  Reading symbols from ./hello...done.
  (gdb) b main
  Breakpoint 1 at 0x120000968: file hello.c, line 7.
  (gdb) r
  Starting program: /home/rin/hello

  Breakpoint 1, main () at hello.c:7
  7               printf("Hello, World!\n");
  (gdb) s
  Hello, World!
  8               return 0;
  (gdb) s
  9       }
  (gdb) s
  0x00000001200008b8 in ___start ()
  (gdb) s
  Single stepping until exit from function ___start,
  which has no line number information.
  [Inferior 1 (process 575) exited normally]
  (gdb) q

However, on other platforms, it steps into printf() if separate debugging
symbols of libc are provided. But it does not on alpha. I will examine it
further...

Thanks,
Rin