Re: [RFA 3/6] Remove cleanup from ppc-linux-nat.c

[Simon Marchi <simon.marchi@ericsson.com>]

On 2017-10-15 11:04 PM, Tom Tromey wrote:
> This removes a cleanup from ppc-linux-nat.c, by using
> unique_xmalloc_ptr.  It also slightly simplifies the code by using
> XDUP rather than XNEW and memcpy.
> 
> ChangeLog
> 2017-10-15  Tom Tromey  <tom@tromey.com>
> 
> 	* ppc-linux-nat.c (hwdebug_insert_point): Use
> 	gdb::unique_xmalloc_ptr, XDUP.
> ---
>  gdb/ChangeLog       |  5 +++++
>  gdb/ppc-linux-nat.c | 11 +++--------
>  2 files changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/gdb/ppc-linux-nat.c b/gdb/ppc-linux-nat.c
> index 45c8903ef6..7c8ab6c67b 100644
> --- a/gdb/ppc-linux-nat.c
> +++ b/gdb/ppc-linux-nat.c
> @@ -1541,16 +1541,13 @@ hwdebug_insert_point (struct ppc_hw_breakpoint *b, int tid)
>  {
>    int i;
>    long slot;
> -  struct ppc_hw_breakpoint *p = XNEW (struct ppc_hw_breakpoint);
> +  gdb::unique_xmalloc_ptr<ppc_hw_breakpoint> p (XDUP (ppc_hw_breakpoint, b));
>    struct hw_break_tuple *hw_breaks;
> -  struct cleanup *c = make_cleanup (xfree, p);
>    struct thread_points *t;
>    struct hw_break_tuple *tuple;
>  
> -  memcpy (p, b, sizeof (struct ppc_hw_breakpoint));
> -
>    errno = 0;
> -  slot = ptrace (PPC_PTRACE_SETHWDEBUG, tid, 0, p);
> +  slot = ptrace (PPC_PTRACE_SETHWDEBUG, tid, 0, p.get ());
>    if (slot < 0)
>      perror_with_name (_("Unexpected error setting breakpoint or watchpoint"));
>  
> @@ -1564,13 +1561,11 @@ hwdebug_insert_point (struct ppc_hw_breakpoint *b, int tid)
>      if (hw_breaks[i].hw_break == NULL)
>        {
>  	hw_breaks[i].slot = slot;
> -	hw_breaks[i].hw_break = p;
> +	hw_breaks[i].hw_break = p.release ();
>  	break;
>        }
>  
>    gdb_assert (i != max_slots_number);
> -
> -  discard_cleanups (c);
>  }
>  
>  /* This function is a generic wrapper that is responsible for removing a
> 

I was going to say, it would make more sense to use the copy constructor:

  std::unique_ptr<ppc_hw_breakpoint> p (new ppc_hw_breakpoint (*b));

but it would require other changes, and it's probably out of scope for your
current goal, so LGTM.

Simon