Remove save_inferior_ptid

This removes save_inferior_ptid, a cleanup function, in favor of
scoped_restore.

This also fixes a possible (it seems unlikely that it could happen in
practice) memory leak -- save_inferior_ptid should have used
make_cleanup_dtor, because it allocated memory.

I tested this on the buildbot.  However, there are two caveats to
this.  First, sometimes it seems I misread the results.  Second, I
think this patch touches some platforms that can't be tested by the
buildbot.  So, extra care seems warranted.

ChangeLog
2017-08-18  Tom Tromey  <tom@tromey.com>
	    Pedro Alves  <palves@redhat.com>

	* spu-multiarch.c (parse_spufs_run): Use scoped_restore.
	* sol-thread.c (sol_thread_resume, sol_thread_wait)
	(sol_thread_xfer_partial, rw_common): Use scoped_restore.
	* procfs.c (procfs_do_thread_registers): Use scoped_restore.
	* proc-service.c (ps_xfer_memory): Use scoped_restore.
	* linux-tdep.c (linux_corefile_thread): Remove a cleanup.
	(linux_get_siginfo_data): Add "thread" argument.  Use
	scoped_restore.
	* linux-nat.c (linux_child_follow_fork)
	(check_stopped_by_watchpoint): Use scoped_restore.
	* infrun.c (displaced_step_prepare_throw, write_memory_ptid)
	(THREAD_STOPPED_BY, handle_signal_stop): Use scoped_restore.
	(restore_inferior_ptid, save_inferior_ptid): Remove.
	* btrace.c (btrace_fetch): Use scoped_restore.
	* bsd-uthread.c (bsd_uthread_fetch_registers)
	(bsd_uthread_store_registers): Use scoped_restore.
	* breakpoint.c (reattach_breakpoints, detach_breakpoints): Use
	scoped_restore.
	* aix-thread.c (aix_thread_resume, aix_thread_wait)
	(aix_thread_xfer_partial): Use scoped_restore.
	* inferior.h (save_inferior_ptid): Remove.

13 files changed, 78 insertions, 133 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 5929091..7ad3f4c 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,28 @@
+2017-08-18  Tom Tromey  <tom@tromey.com>
+	    Pedro Alves  <palves@redhat.com>
+
+	* spu-multiarch.c (parse_spufs_run): Use scoped_restore.
+	* sol-thread.c (sol_thread_resume, sol_thread_wait)
+	(sol_thread_xfer_partial, rw_common): Use scoped_restore.
+	* procfs.c (procfs_do_thread_registers): Use scoped_restore.
+	* proc-service.c (ps_xfer_memory): Use scoped_restore.
+	* linux-tdep.c (linux_corefile_thread): Remove a cleanup.
+	(linux_get_siginfo_data): Add "thread" argument.  Use
+	scoped_restore.
+	* linux-nat.c (linux_child_follow_fork)
+	(check_stopped_by_watchpoint): Use scoped_restore.
+	* infrun.c (displaced_step_prepare_throw, write_memory_ptid)
+	(THREAD_STOPPED_BY, handle_signal_stop): Use scoped_restore.
+	(restore_inferior_ptid, save_inferior_ptid): Remove.
+	* btrace.c (btrace_fetch): Use scoped_restore.
+	* bsd-uthread.c (bsd_uthread_fetch_registers)
+	(bsd_uthread_store_registers): Use scoped_restore.
+	* breakpoint.c (reattach_breakpoints, detach_breakpoints): Use
+	scoped_restore.
+	* aix-thread.c (aix_thread_resume, aix_thread_wait)
+	(aix_thread_xfer_partial): Use scoped_restore.
+	* inferior.h (save_inferior_ptid): Remove.
+
 2017-08-18  Yao Qi  <yao.qi@linaro.org>
 
 	PR tdep/21818
diff --git a/gdb/aix-thread.c b/gdb/aix-thread.c
index ced6203..f3434a6 100644
--- a/gdb/aix-thread.c
+++ b/gdb/aix-thread.c
@@ -985,12 +985,11 @@ aix_thread_resume (struct target_ops *ops,
 
   if (!PD_TID (ptid))
     {
-      struct cleanup *cleanup = save_inferior_ptid ();
+      scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
       struct target_ops *beneath = find_target_beneath (ops);
       
       inferior_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
       beneath->to_resume (beneath, ptid, step, sig);
-      do_cleanups (cleanup);
     }
   else
     {
@@ -1022,14 +1021,16 @@ static ptid_t
 aix_thread_wait (struct target_ops *ops,
 		 ptid_t ptid, struct target_waitstatus *status, int options)
 {
-  struct cleanup *cleanup = save_inferior_ptid ();
   struct target_ops *beneath = find_target_beneath (ops);
 
-  pid_to_prc (&ptid);
+  {
+    scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
 
-  inferior_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
-  ptid = beneath->to_wait (beneath, ptid, status, options);
-  do_cleanups (cleanup);
+    pid_to_prc (&ptid);
+
+    inferior_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
+    ptid = beneath->to_wait (beneath, ptid, status, options);
+  }
 
   if (ptid_get_pid (ptid) == -1)
     return pid_to_ptid (-1);
@@ -1684,16 +1685,12 @@ aix_thread_xfer_partial (struct target_ops *ops, enum target_object object,
 			 const gdb_byte *writebuf,
 			 ULONGEST offset, ULONGEST len, ULONGEST *xfered_len)
 {
-  struct cleanup *old_chain = save_inferior_ptid ();
-  enum target_xfer_status xfer;
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
   struct target_ops *beneath = find_target_beneath (ops);
 
   inferior_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
-  xfer = beneath->to_xfer_partial (beneath, object, annex, readbuf,
+  return beneath->to_xfer_partial (beneath, object, annex, readbuf,
 				   writebuf, offset, len, xfered_len);
-
-  do_cleanups (old_chain);
-  return xfer;
 }
 
 /* Clean up after the inferior exits.  */
diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
index 3dc9112..bc681cf 100644
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -3302,7 +3302,6 @@ remove_breakpoints_pid (int pid)
 int
 reattach_breakpoints (int pid)
 {
-  struct cleanup *old_chain;
   struct bp_location *bl, **blp_tmp;
   int val;
   int dummy1 = 0, dummy2 = 0, dummy3 = 0;
@@ -3314,8 +3313,8 @@ reattach_breakpoints (int pid)
     return 1;
 
   inf = find_inferior_pid (pid);
-  old_chain = save_inferior_ptid ();
 
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
   inferior_ptid = tp->ptid;
 
   string_file tmp_error_stream;
@@ -3330,13 +3329,9 @@ reattach_breakpoints (int pid)
 	bl->inserted = 0;
 	val = insert_bp_location (bl, &tmp_error_stream, &dummy1, &dummy2, &dummy3);
 	if (val != 0)
-	  {
-	    do_cleanups (old_chain);
-	    return val;
-	  }
+	  return val;
       }
   }
-  do_cleanups (old_chain);
   return 0;
 }
 
@@ -3913,7 +3908,7 @@ detach_breakpoints (ptid_t ptid)
 {
   struct bp_location *bl, **blp_tmp;
   int val = 0;
-  struct cleanup *old_chain = save_inferior_ptid ();
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
   struct inferior *inf = current_inferior ();
 
   if (ptid_get_pid (ptid) == ptid_get_pid (inferior_ptid))
@@ -3939,7 +3934,6 @@ detach_breakpoints (ptid_t ptid)
       val |= remove_breakpoint_1 (bl, DETACH_BREAKPOINT);
   }
 
-  do_cleanups (old_chain);
   return val;
 }
 
diff --git a/gdb/bsd-uthread.c b/gdb/bsd-uthread.c
index 9769d20..9249700 100644
--- a/gdb/bsd-uthread.c
+++ b/gdb/bsd-uthread.c
@@ -294,7 +294,7 @@ bsd_uthread_fetch_registers (struct target_ops *ops,
   CORE_ADDR addr = ptid_get_tid (ptid);
   struct target_ops *beneath = find_target_beneath (ops);
   CORE_ADDR active_addr;
-  struct cleanup *cleanup = save_inferior_ptid ();
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
 
   /* We are doing operations (e.g. reading memory) that rely on
      inferior_ptid.  */
@@ -315,8 +315,6 @@ bsd_uthread_fetch_registers (struct target_ops *ops,
       uthread_ops->supply_uthread (regcache, regnum,
 				   addr + bsd_uthread_thread_ctx_offset);
     }
-
-  do_cleanups (cleanup);
 }
 
 static void
@@ -330,7 +328,7 @@ bsd_uthread_store_registers (struct target_ops *ops,
   ptid_t ptid = regcache_get_ptid (regcache);
   CORE_ADDR addr = ptid_get_tid (ptid);
   CORE_ADDR active_addr;
-  struct cleanup *cleanup = save_inferior_ptid ();
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
 
   /* We are doing operations (e.g. reading memory) that rely on
      inferior_ptid.  */
@@ -349,8 +347,6 @@ bsd_uthread_store_registers (struct target_ops *ops,
          request to the layer beneath.  */
       beneath->to_store_registers (beneath, regcache, regnum);
     }
-
-  do_cleanups (cleanup);
 }
 
 static ptid_t
diff --git a/gdb/btrace.c b/gdb/btrace.c
index 10224c5..2a83e1b 100644
--- a/gdb/btrace.c
+++ b/gdb/btrace.c
@@ -1908,14 +1908,14 @@ btrace_fetch (struct thread_info *tp)
   /* With CLI usage, TP->PTID always equals INFERIOR_PTID here.  Now that we
      can store a gdb.Record object in Python referring to a different thread
      than the current one, temporarily set INFERIOR_PTID.  */
-  cleanup = save_inferior_ptid ();
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
   inferior_ptid = tp->ptid;
 
   /* We should not be called on running or exited threads.  */
   gdb_assert (can_access_registers_ptid (tp->ptid));
 
   btrace_data_init (&btrace);
-  make_cleanup_btrace_data (&btrace);
+  cleanup = make_cleanup_btrace_data (&btrace);
 
   /* Let's first try to extend the trace we already have.  */
   if (!btinfo->functions.empty ())
diff --git a/gdb/inferior.h b/gdb/inferior.h
index 8ada4f8..c2b5db4 100644
--- a/gdb/inferior.h
+++ b/gdb/inferior.h
@@ -73,11 +73,6 @@ extern void discard_infcall_control_state (struct infcall_control_state *);
 extern struct regcache *
   get_infcall_suspend_state_regcache (struct infcall_suspend_state *);
 
-/* Save value of inferior_ptid so that it may be restored by
-   a later call to do_cleanups().  Returns the struct cleanup
-   pointer needed for later doing the cleanup.  */
-extern struct cleanup * save_inferior_ptid (void);
-
 extern void set_sigint_trap (void);
 
 extern void clear_sigint_trap (void);
diff --git a/gdb/infrun.c b/gdb/infrun.c
index d6723fd..541fc09 100644
--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -1756,7 +1756,7 @@ displaced_step_dump_bytes (struct ui_file *file,
 static int
 displaced_step_prepare_throw (ptid_t ptid)
 {
-  struct cleanup *old_cleanups, *ignore_cleanups;
+  struct cleanup *ignore_cleanups;
   struct thread_info *tp = find_thread_ptid (ptid);
   struct regcache *regcache = get_thread_regcache (ptid);
   struct gdbarch *gdbarch = get_regcache_arch (regcache);
@@ -1808,7 +1808,7 @@ displaced_step_prepare_throw (ptid_t ptid)
 
   displaced_step_clear (displaced);
 
-  old_cleanups = save_inferior_ptid ();
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
   inferior_ptid = ptid;
 
   original = regcache_read_pc (regcache);
@@ -1834,7 +1834,6 @@ displaced_step_prepare_throw (ptid_t ptid)
 			      "Stepping over breakpoint in-line instead.\n");
 	}
 
-      do_cleanups (old_cleanups);
       return -1;
     }
 
@@ -1864,7 +1863,7 @@ displaced_step_prepare_throw (ptid_t ptid)
       /* The architecture doesn't know how or want to displaced step
 	 this instruction or instruction sequence.  Fallback to
 	 stepping over the breakpoint in-line.  */
-      do_cleanups (old_cleanups);
+      do_cleanups (ignore_cleanups);
       return -1;
     }
 
@@ -1883,8 +1882,6 @@ displaced_step_prepare_throw (ptid_t ptid)
 
   discard_cleanups (ignore_cleanups);
 
-  do_cleanups (old_cleanups);
-
   if (debug_displaced)
     fprintf_unfiltered (gdb_stdlog, "displaced: displaced pc to %s\n",
 			paddress (gdbarch, copy));
@@ -1941,11 +1938,10 @@ static void
 write_memory_ptid (ptid_t ptid, CORE_ADDR memaddr,
 		   const gdb_byte *myaddr, int len)
 {
-  struct cleanup *ptid_cleanup = save_inferior_ptid ();
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
 
   inferior_ptid = ptid;
   write_memory (memaddr, myaddr, len);
-  do_cleanups (ptid_cleanup);
 }
 
 /* Restore the contents of the copy area for thread PTID.  */
@@ -4366,17 +4362,10 @@ wait_one (struct target_waitstatus *ws)
 static int					\
 thread_stopped_by_ ## REASON (ptid_t ptid)	\
 {						\
-  struct cleanup *old_chain;			\
-  int res;					\
-						\
-  old_chain = save_inferior_ptid ();		\
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid); \
   inferior_ptid = ptid;				\
 						\
-  res = target_stopped_by_ ## REASON ();	\
-						\
-  do_cleanups (old_chain);			\
-						\
-  return res;					\
+  return target_stopped_by_ ## REASON ();	\
 }
 
 /* Generate thread_stopped_by_watchpoint.  */
@@ -5706,7 +5695,7 @@ handle_signal_stop (struct execution_control_state *ecs)
     {
       struct regcache *regcache = get_thread_regcache (ecs->ptid);
       struct gdbarch *gdbarch = get_regcache_arch (regcache);
-      struct cleanup *old_chain = save_inferior_ptid ();
+      scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
 
       inferior_ptid = ecs->ptid;
 
@@ -5726,8 +5715,6 @@ handle_signal_stop (struct execution_control_state *ecs)
             fprintf_unfiltered (gdb_stdlog,
                                 "infrun: (no data address available)\n");
 	}
-
-      do_cleanups (old_chain);
     }
 
   /* This is originated from start_remote(), start_inferior() and
@@ -9116,32 +9103,6 @@ discard_infcall_control_state (struct infcall_control_state *inf_status)
   xfree (inf_status);
 }
 
-/* restore_inferior_ptid() will be used by the cleanup machinery
-   to restore the inferior_ptid value saved in a call to
-   save_inferior_ptid().  */
-
-static void
-restore_inferior_ptid (void *arg)
-{
-  ptid_t *saved_ptid_ptr = (ptid_t *) arg;
-
-  inferior_ptid = *saved_ptid_ptr;
-  xfree (arg);
-}
-
-/* Save the value of inferior_ptid so that it may be restored by a
-   later call to do_cleanups().  Returns the struct cleanup pointer
-   needed for later doing the cleanup.  */
-
-struct cleanup *
-save_inferior_ptid (void)
-{
-  ptid_t *saved_ptid_ptr = XNEW (ptid_t);
-
-  *saved_ptid_ptr = inferior_ptid;
-  return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
-}
-
 /* See infrun.h.  */
 
 void
diff --git a/gdb/linux-nat.c b/gdb/linux-nat.c
index b9c7d1f..4124318 100644
--- a/gdb/linux-nat.c
+++ b/gdb/linux-nat.c
@@ -477,7 +477,6 @@ linux_child_follow_fork (struct target_ops *ops, int follow_child,
     {
       struct lwp_info *child_lp = NULL;
       int status = W_STOPCODE (0);
-      struct cleanup *old_chain;
       int has_vforked;
       ptid_t parent_ptid, child_ptid;
       int parent_pid, child_pid;
@@ -490,16 +489,15 @@ linux_child_follow_fork (struct target_ops *ops, int follow_child,
       child_pid = ptid_get_lwp (child_ptid);
 
       /* We're already attached to the parent, by default.  */
-      old_chain = save_inferior_ptid ();
-      inferior_ptid = child_ptid;
-      child_lp = add_lwp (inferior_ptid);
+      child_lp = add_lwp (child_ptid);
       child_lp->stopped = 1;
       child_lp->last_resume_kind = resume_stop;
 
       /* Detach new forked process?  */
       if (detach_fork)
 	{
-	  make_cleanup (delete_lwp_cleanup, child_lp);
+	  struct cleanup *old_chain = make_cleanup (delete_lwp_cleanup,
+						    child_lp);
 
 	  if (linux_nat_prepare_to_resume != NULL)
 	    linux_nat_prepare_to_resume (child_lp);
@@ -513,7 +511,7 @@ linux_child_follow_fork (struct target_ops *ops, int follow_child,
 	     once before detaching to clear the flags.  */
 
 	  if (!gdbarch_software_single_step_p (target_thread_architecture
-						   (child_lp->ptid)))
+					       (child_lp->ptid)))
 	    {
 	      linux_disable_event_reporting (child_pid);
 	      if (ptrace (PTRACE_SINGLESTEP, child_pid, 0, 0) < 0)
@@ -533,17 +531,18 @@ linux_child_follow_fork (struct target_ops *ops, int follow_child,
 	      ptrace (PTRACE_DETACH, child_pid, 0, signo);
 	    }
 
-	  /* Resets value of inferior_ptid to parent ptid.  */
 	  do_cleanups (old_chain);
 	}
       else
 	{
+	  scoped_restore save_inferior_ptid
+	    = make_scoped_restore (&inferior_ptid);
+	  inferior_ptid = child_ptid;
+
 	  /* Let the thread_db layer learn about this new process.  */
 	  check_for_thread_db ();
 	}
 
-      do_cleanups (old_chain);
-
       if (has_vforked)
 	{
 	  struct lwp_info *parent_lp;
@@ -2458,12 +2457,10 @@ maybe_clear_ignore_sigint (struct lwp_info *lp)
 static int
 check_stopped_by_watchpoint (struct lwp_info *lp)
 {
-  struct cleanup *old_chain;
-
   if (linux_ops->to_stopped_by_watchpoint == NULL)
     return 0;
 
-  old_chain = save_inferior_ptid ();
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
   inferior_ptid = lp->ptid;
 
   if (linux_ops->to_stopped_by_watchpoint (linux_ops))
@@ -2478,8 +2475,6 @@ check_stopped_by_watchpoint (struct lwp_info *lp)
 	lp->stopped_data_address_p = 0;
     }
 
-  do_cleanups (old_chain);
-
   return lp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
 }
 
diff --git a/gdb/linux-tdep.c b/gdb/linux-tdep.c
index 5c7f8a0..f5389a0 100644
--- a/gdb/linux-tdep.c
+++ b/gdb/linux-tdep.c
@@ -1649,14 +1649,15 @@ linux_collect_thread_registers (const struct regcache *regcache,
   return data.note_data;
 }
 
-/* Fetch the siginfo data for the current thread, if it exists.  If
+/* Fetch the siginfo data for the specified thread, if it exists.  If
    there is no data, or we could not read it, return NULL.  Otherwise,
    return a newly malloc'd buffer holding the data and fill in *SIZE
    with the size of the data.  The caller is responsible for freeing
    the data.  */
 
 static gdb_byte *
-linux_get_siginfo_data (struct gdbarch *gdbarch, LONGEST *size)
+linux_get_siginfo_data (thread_info *thread, struct gdbarch *gdbarch,
+			LONGEST *size)
 {
   struct type *siginfo_type;
   gdb_byte *buf;
@@ -1666,6 +1667,9 @@ linux_get_siginfo_data (struct gdbarch *gdbarch, LONGEST *size)
   if (!gdbarch_get_siginfo_type_p (gdbarch))
     return NULL;
   
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
+  inferior_ptid = thread->ptid;
+
   siginfo_type = gdbarch_get_siginfo_type (gdbarch);
 
   buf = (gdb_byte *) xmalloc (TYPE_LENGTH (siginfo_type));
@@ -1710,11 +1714,8 @@ linux_corefile_thread (struct thread_info *info,
 
   regcache = get_thread_arch_regcache (info->ptid, args->gdbarch);
 
-  old_chain = save_inferior_ptid ();
-  inferior_ptid = info->ptid;
   target_fetch_registers (regcache, -1);
-  siginfo_data = linux_get_siginfo_data (args->gdbarch, &siginfo_size);
-  do_cleanups (old_chain);
+  siginfo_data = linux_get_siginfo_data (info, args->gdbarch, &siginfo_size);
 
   old_chain = make_cleanup (xfree, siginfo_data);
 
diff --git a/gdb/proc-service.c b/gdb/proc-service.c
index 5e5eee0..1e5433c 100644
--- a/gdb/proc-service.c
+++ b/gdb/proc-service.c
@@ -87,7 +87,7 @@ static ps_err_e
 ps_xfer_memory (const struct ps_prochandle *ph, psaddr_t addr,
 		gdb_byte *buf, size_t len, int write)
 {
-  struct cleanup *old_chain = save_inferior_ptid ();
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
   int ret;
   CORE_ADDR core_addr = ps_addr_to_core_addr (addr);
 
@@ -98,8 +98,6 @@ ps_xfer_memory (const struct ps_prochandle *ph, psaddr_t addr,
   else
     ret = target_read_memory (core_addr, buf, len);
 
-  do_cleanups (old_chain);
-
   return (ret == 0 ? PS_OK : PS_ERR);
 }
 
diff --git a/gdb/procfs.c b/gdb/procfs.c
index 4b965ea..504d74c 100644
--- a/gdb/procfs.c
+++ b/gdb/procfs.c
@@ -5316,7 +5316,6 @@ procfs_do_thread_registers (bfd *obfd, ptid_t ptid,
   gdb_gregset_t gregs;
   gdb_fpregset_t fpregs;
   unsigned long merged_pid;
-  struct cleanup *old_chain;
 
   merged_pid = ptid_get_lwp (ptid) << 16 | ptid_get_pid (ptid);
 
@@ -5325,7 +5324,7 @@ procfs_do_thread_registers (bfd *obfd, ptid_t ptid,
      once it is implemented in this platform:
      gdbarch_iterate_over_regset_sections().  */
 
-  old_chain = save_inferior_ptid ();
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
   inferior_ptid = ptid;
   target_fetch_registers (regcache, -1);
 
@@ -5352,8 +5351,6 @@ procfs_do_thread_registers (bfd *obfd, ptid_t ptid,
 					      &fpregs,
 					      sizeof (fpregs));
 
-  do_cleanups (old_chain);
-
   return note_data;
 }
 
diff --git a/gdb/sol-thread.c b/gdb/sol-thread.c
index 02515b2..c4d4b02 100644
--- a/gdb/sol-thread.c
+++ b/gdb/sol-thread.c
@@ -367,10 +367,9 @@ static void
 sol_thread_resume (struct target_ops *ops,
 		   ptid_t ptid, int step, enum gdb_signal signo)
 {
-  struct cleanup *old_chain;
   struct target_ops *beneath = find_target_beneath (ops);
 
-  old_chain = save_inferior_ptid ();
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
 
   inferior_ptid = thread_to_lwp (inferior_ptid, ptid_get_pid (main_ph.ptid));
   if (ptid_get_pid (inferior_ptid) == -1)
@@ -389,8 +388,6 @@ sol_thread_resume (struct target_ops *ops,
     }
 
   beneath->to_resume (beneath, ptid, step, signo);
-
-  do_cleanups (old_chain);
 }
 
 /* Wait for any threads to stop.  We may have to convert PTID from a
@@ -403,10 +400,9 @@ sol_thread_wait (struct target_ops *ops,
   ptid_t rtnval;
   ptid_t save_ptid;
   struct target_ops *beneath = find_target_beneath (ops);
-  struct cleanup *old_chain;
 
   save_ptid = inferior_ptid;
-  old_chain = save_inferior_ptid ();
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
 
   inferior_ptid = thread_to_lwp (inferior_ptid, ptid_get_pid (main_ph.ptid));
   if (ptid_get_pid (inferior_ptid) == -1)
@@ -445,8 +441,6 @@ sol_thread_wait (struct target_ops *ops,
      package being initialized, since that can only happen after we've
      found the shared libs.  */
 
-  do_cleanups (old_chain);
-
   return rtnval;
 }
 
@@ -569,11 +563,9 @@ sol_thread_xfer_partial (struct target_ops *ops, enum target_object object,
 			  const gdb_byte *writebuf,
 			 ULONGEST offset, ULONGEST len, ULONGEST *xfered_len)
 {
-  enum target_xfer_status retval;
-  struct cleanup *old_chain;
   struct target_ops *beneath = find_target_beneath (ops);
 
-  old_chain = save_inferior_ptid ();
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
 
   if (ptid_tid_p (inferior_ptid) || !target_thread_alive (inferior_ptid))
     {
@@ -585,12 +577,8 @@ sol_thread_xfer_partial (struct target_ops *ops, enum target_object object,
       inferior_ptid = procfs_first_available ();
     }
 
-  retval = beneath->to_xfer_partial (beneath, object, annex, readbuf,
-				     writebuf, offset, len, xfered_len);
-
-  do_cleanups (old_chain);
-
-  return retval;
+  return beneath->to_xfer_partial (beneath, object, annex, readbuf,
+				   writebuf, offset, len, xfered_len);
 }
 
 static void
@@ -800,9 +788,8 @@ rw_common (int dowrite, const struct ps_prochandle *ph, gdb_ps_addr_t addr,
 	   gdb_byte *buf, int size)
 {
   int ret;
-  struct cleanup *old_chain;
 
-  old_chain = save_inferior_ptid ();
+  scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
 
   if (ptid_tid_p (inferior_ptid) || !target_thread_alive (inferior_ptid))
     {
@@ -826,8 +813,6 @@ rw_common (int dowrite, const struct ps_prochandle *ph, gdb_ps_addr_t addr,
   else
     ret = target_read_memory (addr, (gdb_byte *) buf, size);
 
-  do_cleanups (old_chain);
-
   return (ret == 0 ? PS_OK : PS_ERR);
 }
 
diff --git a/gdb/spu-multiarch.c b/gdb/spu-multiarch.c
index 3da502c..7682ca2 100644
--- a/gdb/spu-multiarch.c
+++ b/gdb/spu-multiarch.c
@@ -76,10 +76,11 @@ parse_spufs_run (ptid_t ptid, int *fd, CORE_ADDR *addr)
   tdep = gdbarch_tdep (target_gdbarch ());
 
   /* Fetch instruction preceding current NIP.  */
-  old_chain = save_inferior_ptid ();
-  inferior_ptid = ptid;
-  regval = target_read_memory (regcache_read_pc (regcache) - 4, buf, 4);
-  do_cleanups (old_chain);
+  {
+    scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid);
+    inferior_ptid = ptid;
+    regval = target_read_memory (regcache_read_pc (regcache) - 4, buf, 4);
+  }
   if (regval != 0)
     return 0;
   /* It should be a "sc" instruction.  */