[v2,3/5] Use gdb::unique_xmalloc_ptr<> instead of a deleter that invokes free().

Since xfree() always wraps free(), it is safe to use the xfree deleter
for buffers allocated by library routines such as kinfo_getvmmap() that
must be released via free().

gdb/ChangeLog:

	* fbsd-nat.c (struct free_deleter): Remove.
	(fbsd_find_memory_regions): Use gdb::unique_xmalloc_ptr<>.
---
 gdb/ChangeLog  |  5 +++++
 gdb/fbsd-nat.c | 10 +---------
 2 files changed, 6 insertions(+), 9 deletions(-)

On 2018-01-03 08:49 PM, John Baldwin wrote:
> Since xfree() always wraps free(), it is safe to use the xfree deleter
> for buffers allocated by library routines such as kinfo_getvmmap() that
> must be released via free().
> 
> gdb/ChangeLog:
> 
> 	* fbsd-nat.c (struct free_deleter): Remove.
> 	(fbsd_find_memory_regions): Use gdb::unique_xmalloc_ptr<>.
> ---
>  gdb/ChangeLog  |  5 +++++
>  gdb/fbsd-nat.c | 10 +---------
>  2 files changed, 6 insertions(+), 9 deletions(-)
> 
> diff --git a/gdb/ChangeLog b/gdb/ChangeLog
> index 804dd4f402..cdce396e9c 100644
> --- a/gdb/ChangeLog
> +++ b/gdb/ChangeLog
> @@ -1,3 +1,8 @@
> +2018-01-03  John Baldwin  <jhb@FreeBSD.org>
> +
> +	* fbsd-nat.c (struct free_deleter): Remove.
> +	(fbsd_find_memory_regions): Use gdb::unique_xmalloc_ptr<>.
> +
>  2018-01-03  John Baldwin  <jhb@FreeBSD.org>
>  
>  	* fbsd-nat.c (fbsd_pid_to_exec_file) [KERN_PROC_PATHNAME]: Return
> diff --git a/gdb/fbsd-nat.c b/gdb/fbsd-nat.c
> index 7b1d1bf148..00e5cfb55c 100644
> --- a/gdb/fbsd-nat.c
> +++ b/gdb/fbsd-nat.c
> @@ -78,14 +78,6 @@ fbsd_pid_to_exec_file (struct target_ops *self, int pid)
>  }
>  
>  #ifdef HAVE_KINFO_GETVMMAP
> -/* Deleter for std::unique_ptr that invokes free.  */
> -
> -template <typename T>
> -struct free_deleter
> -{
> -  void operator() (T *ptr) const { free (ptr); }
> -};
> -
>  /* Iterate over all the memory regions in the current inferior,
>     calling FUNC for each memory region.  OBFD is passed as the last
>     argument to FUNC.  */
> @@ -99,7 +91,7 @@ fbsd_find_memory_regions (struct target_ops *self,
>    uint64_t size;
>    int i, nitems;
>  
> -  std::unique_ptr<struct kinfo_vmentry, free_deleter<struct kinfo_vmentry>>
> +  gdb::unique_xmalloc_ptr<struct kinfo_vmentry>
>      vmentl (kinfo_getvmmap (pid, &nitems));
>    if (vmentl == NULL)
>      perror_with_name (_("Couldn't fetch VM map entries."));
> 

LGTM, unless there's something I really havn't understood about xfree.

Simon