Introduce new_bfd_ref

This introduces a helper function, new_bfd_ref, that calls gdb_bfd_ref
and returns a gdb_bfd_ref_ptr.  Then it updates several places to use
this.

ChangeLog
2017-10-20  Tom Tromey  <tom@tromey.com>

	* exec.c (exec_file_attach): Use new_bfd_ref.
	* symfile-mem.c (symbol_file_add_from_memory): Use new_bfd_ref.
	* gdb_bfd.c (gdb_bfd_open, gdb_bfd_fopen, gdb_bfd_openr)
	(gdb_bfd_openw, gdb_bfd_openr_iovec, gdb_bfd_fdopenr): Use
	new_bfd_ref.
	* gdb_bfd.h (new_bfd_ref): New function.

1 files changed, 1 insertions, 2 deletions

diff --git a/gdb/exec.c b/gdb/exec.c
index 2fa543b..326cfff 100644
--- a/gdb/exec.c
+++ b/gdb/exec.c
@@ -248,8 +248,7 @@ exec_file_attach (const char *filename, int from_tty)
   /* First, acquire a reference to the current exec_bfd.  We release
      this at the end of the function; but acquiring it now lets the
      BFD cache return it if this call refers to the same file.  */
-  gdb_bfd_ref (exec_bfd);
-  gdb_bfd_ref_ptr exec_bfd_holder (exec_bfd);
+  gdb_bfd_ref_ptr exec_bfd_holder = new_bfd_ref (exec_bfd);
 
   /* Remove any previous exec file.  */
   exec_close ();