cleanup fixes for inf-ptrace.c

This is one of the stylistic patches.  The code here in inf-ptrace.c
is not incorrect, but it is in a style that the cleanup checker cannot
handle.  This patch changes it to a simpler style, following the usual
method of introducing an unconditional "outer" cleanup.

	* inf-ptrace.c (inf_ptrace_create_inferior): Unconditionally
	call discard_cleanups.
	(inf_ptrace_attach): Likewise.

1 files changed, 6 insertions, 8 deletions

diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c
index 27bbf4d..046e0ce 100644
--- a/gdb/inf-ptrace.c
+++ b/gdb/inf-ptrace.c
@@ -122,20 +122,19 @@ inf_ptrace_create_inferior (struct target_ops *ops,
   /* Do not change either targets above or the same target if already present.
      The reason is the target stack is shared across multiple inferiors.  */
   int ops_already_pushed = target_is_pushed (ops);
-  struct cleanup *back_to = NULL;
+  struct cleanup *back_to = make_cleanup (null_cleanup, NULL);
 
   if (! ops_already_pushed)
     {
       /* Clear possible core file with its process_stratum.  */
       push_target (ops);
-      back_to = make_cleanup_unpush_target (ops);
+      make_cleanup_unpush_target (ops);
     }
 
   pid = fork_inferior (exec_file, allargs, env, inf_ptrace_me, NULL,
 		       NULL, NULL, NULL);
 
-  if (! ops_already_pushed)
-    discard_cleanups (back_to);
+  discard_cleanups (back_to);
 
   /* START_INFERIOR_TRAPS_EXPECTED is defined in inferior.h, and will
      be 1 or 2 depending on whether we're starting without or with a
@@ -196,7 +195,7 @@ inf_ptrace_attach (struct target_ops *ops, char *args, int from_tty)
   /* Do not change either targets above or the same target if already present.
      The reason is the target stack is shared across multiple inferiors.  */
   int ops_already_pushed = target_is_pushed (ops);
-  struct cleanup *back_to = NULL;
+  struct cleanup *back_to = make_cleanup (null_cleanup, NULL);
 
   pid = parse_pid_to_attach (args);
 
@@ -208,7 +207,7 @@ inf_ptrace_attach (struct target_ops *ops, char *args, int from_tty)
       /* target_pid_to_str already uses the target.  Also clear possible core
 	 file with its process_stratum.  */
       push_target (ops);
-      back_to = make_cleanup_unpush_target (ops);
+      make_cleanup_unpush_target (ops);
     }
 
   if (from_tty)
@@ -243,8 +242,7 @@ inf_ptrace_attach (struct target_ops *ops, char *args, int from_tty)
      target, it should decorate the ptid later with more info.  */
   add_thread_silent (inferior_ptid);
 
-  if (! ops_already_pushed)
-    discard_cleanups (back_to);
+  discard_cleanups (back_to);
 }
 
 #ifdef PT_GET_PROCESS_STATE