Patchwork [1/3] Remove args from target detach

login
register
mail settings
Submitter Simon Marchi
Date Dec. 31, 2017, 5:50 a.m.
Message ID <1514699454-18587-1-git-send-email-simon.marchi@ericsson.com>
Download mbox | patch
Permalink /patch/25158/
State New
Headers show

Comments

Simon Marchi - Dec. 31, 2017, 5:50 a.m.
I was looking into adding a parameter to target_detach, and was
wondering what the args parameter was.  It seems like in the distant
past, it was possible to specify a signal number when detaching.  That
signal was injected in the process before it was detached.  There is an
example of code handling this in linux_nat_detach.  With today's GDB, I
can't get this to work.  Doing "detach 15" (15 == SIGTERM) doesn't work,
because detach is a prefix command and doesn't recognize the sub-command
15.  Doing "detach inferiors 15" doesn't work because it expects a list
of inferior id to detach.  Therefore, I don't think there's a way of
invoking detach_command with a non-NULL args.  I also didn't find any
documentation related to this feature.

I assume that this feature stopped working when detach was made a prefix
command, which is in f73adfeb8bae36885e6ea248d12223ab0d5eb9cb (sorry,
there's no commit title) from 2006.  Given that this feature was broken
for such a long time and we haven't heard anything (AFAIK, I did not
find any related bug), I think it's safe to remove it, as well as the
args parameter to target_detach.  If someone wants to re-introduce it, I
would suggest rethinking the user interface, and in particular would
suggest using signal name instead of numbers.

I tried to fix all the impacted code, but I might have forgotten some
spots.  It shouldn't be hard to fix if that's the case.  I also couldn't
build-test everything I changed, especially the nto and solaris stuff.

gdb/ChangeLog:

	* target.h (struct target_ops) <to_detach>: Remove args
	parameter.
	(target_detach): Likewise.
	* target.c (dispose_inferior): Adjust.
	(target_detach): Remove args parameter, adjust.
	* aix-thread.c (aix_thread_detach): Adjust.
	* corefile.c (core_file_command): Adjust.
	* corelow.c (core_detach): Adjust.
	* darwin-nat.c (darwin_detach): Adjust.
	* gnu-nat.c (gnu_detach): Adjust.
	* inf-ptrace.c (inf_ptrace_detach): Adjust.
	* infcmd.c (detach_command): Adjust
	* infrun.c (follow_fork_inferior): Adjust.
	(handle_vfork_child_exec_or_exit): Adjust.
	* linux-fork.c (linux_fork_detach): Remove args parameter.
	* linux-fork.h (linux_fork_detach): Likewise.
	* linux-nat.c (linux_nat_detach): Likewise, and adjust.
	* linux-thread-db.c (thread_db_detach): Likewise.
	* nto-procfs.c (procfs_detach): Likewise.
	* procfs.c (procfs_detach): Likewise.
	* record.c (record_detach): Likewise.
	* record.h (record_detach): Likewise.
	* remote-sim.c (gdbsim_detach): Likewise.
	* remote.c (remote_detach_1): Likewise.
	(remote_detach): Likewise.
	(extended_remote_detach): Likewise.
	* sol-thread.c (sol_thread_detach): Likewise.
	* target-delegates.c: Re-generate.
	* top.c (struct qt_args) <args>: Remove field.
	(kill_or_detach): Don't pass args.
	(quit_force): Don't set args.
	* windows-nat.c (windows_detach): Remove args parameter.
---
 gdb/aix-thread.c       |  4 ++--
 gdb/corefile.c         |  2 +-
 gdb/corelow.c          |  4 +---
 gdb/darwin-nat.c       |  2 +-
 gdb/gnu-nat.c          |  2 +-
 gdb/inf-ptrace.c       | 10 +++-------
 gdb/infcmd.c           |  2 +-
 gdb/infrun.c           |  4 ++--
 gdb/linux-fork.c       |  2 +-
 gdb/linux-fork.h       |  2 +-
 gdb/linux-nat.c        | 15 ++++-----------
 gdb/linux-thread-db.c  |  4 ++--
 gdb/nto-procfs.c       |  8 ++------
 gdb/procfs.c           |  8 ++------
 gdb/record.c           |  4 ++--
 gdb/record.h           |  2 +-
 gdb/remote-sim.c       | 12 +++++-------
 gdb/remote.c           | 13 +++++--------
 gdb/sol-thread.c       |  4 ++--
 gdb/target-delegates.c | 14 ++++++--------
 gdb/target.c           |  8 ++++----
 gdb/target.h           |  9 ++++-----
 gdb/top.c              |  4 +---
 gdb/windows-nat.c      |  2 +-
 24 files changed, 55 insertions(+), 86 deletions(-)
Pedro Alves - Jan. 18, 2018, 3:57 p.m.
On 12/31/2017 05:50 AM, Simon Marchi wrote:
> I was looking into adding a parameter to target_detach, and was
> wondering what the args parameter was.  It seems like in the distant
> past, it was possible to specify a signal number when detaching.  That
> signal was injected in the process before it was detached.  There is an
> example of code handling this in linux_nat_detach.  With today's GDB, I
> can't get this to work.  Doing "detach 15" (15 == SIGTERM) doesn't work,
> because detach is a prefix command and doesn't recognize the sub-command
> 15.  Doing "detach inferiors 15" doesn't work because it expects a list
> of inferior id to detach.  Therefore, I don't think there's a way of
> invoking detach_command with a non-NULL args.  I also didn't find any
> documentation related to this feature.
> 
> I assume that this feature stopped working when detach was made a prefix
> command, which is in f73adfeb8bae36885e6ea248d12223ab0d5eb9cb (sorry,
> there's no commit title) from 2006.  Given that this feature was broken
> for such a long time and we haven't heard anything (AFAIK, I did not
> find any related bug), I think it's safe to remove it, as well as the
> args parameter to target_detach.  If someone wants to re-introduce it, I
> would suggest rethinking the user interface, and in particular would
> suggest using signal name instead of numbers.
> 
> I tried to fix all the impacted code, but I might have forgotten some
> spots.  It shouldn't be hard to fix if that's the case.  I also couldn't
> build-test everything I changed, especially the nto and solaris stuff.
> 

Eh.  I knew about "detach SIG", from touching the detach-related
code many times before.  Had no idea that it was broken.

I think the main use cases are/were:

 - To be able to detach without passing the just-intercepted signal
   to the program.  I.e., "detach 0" was to "detach", like "signal 0"
   is to "continue".

 - To be able to attach to a program (maybe job-stopped), debug it
   a bit, and then detach it, leaving it job-stopped.  I.e., queue
   a SIGSTOP when you detach, with "detach SIGTOP".

I think you can do the former today with either:
  "handle SIGFOO nopass" + "detach"
  "queue-signal 0" + "detach"

and the latter with either:
  "queue-signal SIGSTOP" + "detach"
  "shell kill -SIGSTOP $PID" + "detach"

The "shell kill" variant is a bit more cumbersome, of
course, and only works with native debugging.

We're probably missing testcases for the above scenarios.
IWBN to add them, of course.

The patch looks fine to me.  One nit:

>  static void
> -procfs_detach (struct target_ops *ops, const char *args, int from_tty)
> +procfs_detach (struct target_ops *ops, int from_tty)
>  {
> -  int sig = 0;
>    int pid = ptid_get_pid (inferior_ptid);
>  
> -  if (args)
> -    sig = atoi (args);
> -
>    if (from_tty)
>      {
>        const char *exec_file;
> @@ -1945,7 +1941,7 @@ procfs_detach (struct target_ops *ops, const char *args, int from_tty)
>        gdb_flush (gdb_stdout);
>      }
>  
> -  do_detach (sig);
> +  do_detach (0);

I think the 'signo' parameter of do_detach is now always
0, so it could be removed.  I understand that you might
want to avoid breaking the port (too much), but it looks
very easy to remove.

>  
>    inferior_ptid = null_ptid;
>    detach_inferior (pid);

Thanks,
Pedro Alves

Patch

diff --git a/gdb/aix-thread.c b/gdb/aix-thread.c
index 1a1d769..adb3a83 100644
--- a/gdb/aix-thread.c
+++ b/gdb/aix-thread.c
@@ -981,12 +981,12 @@  aix_thread_inferior_created (struct target_ops *ops, int from_tty)
 /* Detach from the process attached to by aix_thread_attach().  */
 
 static void
-aix_thread_detach (struct target_ops *ops, const char *args, int from_tty)
+aix_thread_detach (struct target_ops *ops, int from_tty)
 {
   struct target_ops *beneath = find_target_beneath (ops);
 
   pd_disable ();
-  beneath->to_detach (beneath, args, from_tty);
+  beneath->to_detach (beneath, from_tty);
 }
 
 /* Tell the inferior process to continue running thread PID if != -1
diff --git a/gdb/corefile.c b/gdb/corefile.c
index 686603a..434c64a 100644
--- a/gdb/corefile.c
+++ b/gdb/corefile.c
@@ -68,7 +68,7 @@  core_file_command (const char *filename, int from_tty)
   gdb_assert (core_target != NULL);
 
   if (!filename)
-    (core_target->to_detach) (core_target, filename, from_tty);
+    (core_target->to_detach) (core_target, from_tty);
   else
     (core_target->to_open) (filename, from_tty);
 }
diff --git a/gdb/corelow.c b/gdb/corelow.c
index 4214896..2894c96 100644
--- a/gdb/corelow.c
+++ b/gdb/corelow.c
@@ -464,10 +464,8 @@  core_open (const char *arg, int from_tty)
 }
 
 static void
-core_detach (struct target_ops *ops, const char *args, int from_tty)
+core_detach (struct target_ops *ops, int from_tty)
 {
-  if (args)
-    error (_("Too many arguments"));
   unpush_target (ops);
   reinit_frame_cache ();
   if (from_tty)
diff --git a/gdb/darwin-nat.c b/gdb/darwin-nat.c
index 5e708c6..1b64536 100644
--- a/gdb/darwin-nat.c
+++ b/gdb/darwin-nat.c
@@ -1938,7 +1938,7 @@  darwin_attach (struct target_ops *ops, const char *args, int from_tty)
    previously attached.  It *might* work if the program was
    started via fork.  */
 static void
-darwin_detach (struct target_ops *ops, const char *args, int from_tty)
+darwin_detach (struct target_ops *ops, int from_tty)
 {
   pid_t pid = ptid_get_pid (inferior_ptid);
   struct inferior *inf = current_inferior ();
diff --git a/gdb/gnu-nat.c b/gdb/gnu-nat.c
index 0d500ea..caa8c3d 100644
--- a/gdb/gnu-nat.c
+++ b/gdb/gnu-nat.c
@@ -2253,7 +2253,7 @@  gnu_attach (struct target_ops *ops, const char *args, int from_tty)
    previously attached.  It *might* work if the program was
    started via fork.  */
 static void
-gnu_detach (struct target_ops *ops, const char *args, int from_tty)
+gnu_detach (struct target_ops *ops, int from_tty)
 {
   int pid;
 
diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c
index e127741..8633108 100644
--- a/gdb/inf-ptrace.c
+++ b/gdb/inf-ptrace.c
@@ -241,18 +241,14 @@  inf_ptrace_post_attach (struct target_ops *self, int pid)
 
 #endif
 
-/* Detach from the inferior, optionally passing it the signal
-   specified by ARGS.  If FROM_TTY is non-zero, be chatty about it.  */
+/* Detach from the inferior.  If FROM_TTY is non-zero, be chatty about it.  */
 
 static void
-inf_ptrace_detach (struct target_ops *ops, const char *args, int from_tty)
+inf_ptrace_detach (struct target_ops *ops, int from_tty)
 {
   pid_t pid = ptid_get_pid (inferior_ptid);
-  int sig = 0;
 
   target_announce_detach (from_tty);
-  if (args)
-    sig = atoi (args);
 
 #ifdef PT_DETACH
   /* We'd better not have left any breakpoints in the program or it'll
@@ -260,7 +256,7 @@  inf_ptrace_detach (struct target_ops *ops, const char *args, int from_tty)
      previously attached to the inferior.  It *might* work if we
      started the process ourselves.  */
   errno = 0;
-  ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, sig);
+  ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, 0);
   if (errno != 0)
     perror_with_name (("ptrace"));
 #else
diff --git a/gdb/infcmd.c b/gdb/infcmd.c
index 1b63f9b..3aa2ced 100644
--- a/gdb/infcmd.c
+++ b/gdb/infcmd.c
@@ -2976,7 +2976,7 @@  detach_command (const char *args, int from_tty)
 
   disconnect_tracing ();
 
-  target_detach (args, from_tty);
+  target_detach (from_tty);
 
   /* The current inferior process was just detached successfully.  Get
      rid of breakpoints that no longer make sense.  Note we don't do
diff --git a/gdb/infrun.c b/gdb/infrun.c
index d7df3c7..c4d168c 100644
--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -606,7 +606,7 @@  holding the child stopped.  Try \"set detach-on-fork\" or \
 				target_pid_to_str (process_ptid));
 	    }
 
-	  target_detach (NULL, 0);
+	  target_detach (0);
 	}
 
       /* Note that the detach above makes PARENT_INF dangling.  */
@@ -976,7 +976,7 @@  handle_vfork_child_exec_or_exit (int exec)
 		}
 	    }
 
-	  target_detach (NULL, 0);
+	  target_detach (0);
 
 	  /* Put it back.  */
 	  inf->pspace = pspace;
diff --git a/gdb/linux-fork.c b/gdb/linux-fork.c
index f55f743..d05cec9 100644
--- a/gdb/linux-fork.c
+++ b/gdb/linux-fork.c
@@ -407,7 +407,7 @@  linux_fork_mourn_inferior (void)
    the first available.  */
 
 void
-linux_fork_detach (const char *args, int from_tty)
+linux_fork_detach (int from_tty)
 {
   /* OK, inferior_ptid is the one we are detaching from.  We need to
      delete it from the fork_list, and switch to the next available
diff --git a/gdb/linux-fork.h b/gdb/linux-fork.h
index 6211482..8af822a 100644
--- a/gdb/linux-fork.h
+++ b/gdb/linux-fork.h
@@ -22,6 +22,6 @@  extern struct fork_info *add_fork (pid_t);
 extern struct fork_info *find_fork_pid (pid_t);
 extern void linux_fork_killall (void);
 extern void linux_fork_mourn_inferior (void);
-extern void linux_fork_detach (const char *, int);
+extern void linux_fork_detach (int);
 extern int forks_exist_p (void);
 extern int linux_fork_checkpointing_p (int);
diff --git a/gdb/linux-nat.c b/gdb/linux-nat.c
index b8f3108..3290ed5 100644
--- a/gdb/linux-nat.c
+++ b/gdb/linux-nat.c
@@ -1507,7 +1507,7 @@  detach_callback (struct lwp_info *lp, void *data)
 }
 
 static void
-linux_nat_detach (struct target_ops *ops, const char *args, int from_tty)
+linux_nat_detach (struct target_ops *ops, int from_tty)
 {
   int pid;
   struct lwp_info *main_lwp;
@@ -1537,21 +1537,14 @@  linux_nat_detach (struct target_ops *ops, const char *args, int from_tty)
 	 from, but there are other viable forks to debug.  Detach from
 	 the current fork, and context-switch to the first
 	 available.  */
-      linux_fork_detach (args, from_tty);
+      linux_fork_detach (from_tty);
     }
   else
     {
-      int signo;
-
       target_announce_detach (from_tty);
 
-      /* Pass on any pending signal for the last LWP, unless the user
-	 requested detaching with a different signal (most likely 0,
-	 meaning, discard the signal).  */
-      if (args != NULL)
-	signo = atoi (args);
-      else
-	signo = get_detach_signal (main_lwp);
+      /* Pass on any pending signal for the last LWP.  */
+      int signo = get_detach_signal (main_lwp);
 
       detach_one_lwp (main_lwp, &signo);
 
diff --git a/gdb/linux-thread-db.c b/gdb/linux-thread-db.c
index 7fe6e2d..ed41640 100644
--- a/gdb/linux-thread-db.c
+++ b/gdb/linux-thread-db.c
@@ -1090,13 +1090,13 @@  record_thread (struct thread_db_info *info,
 }
 
 static void
-thread_db_detach (struct target_ops *ops, const char *args, int from_tty)
+thread_db_detach (struct target_ops *ops, int from_tty)
 {
   struct target_ops *target_beneath = find_target_beneath (ops);
 
   delete_thread_db_info (ptid_get_pid (inferior_ptid));
 
-  target_beneath->to_detach (target_beneath, args, from_tty);
+  target_beneath->to_detach (target_beneath, from_tty);
 
   /* NOTE: From this point on, inferior_ptid is null_ptid.  */
 
diff --git a/gdb/nto-procfs.c b/gdb/nto-procfs.c
index 04f2213..5094eb4 100644
--- a/gdb/nto-procfs.c
+++ b/gdb/nto-procfs.c
@@ -943,18 +943,14 @@  procfs_xfer_partial (struct target_ops *ops, enum target_object object,
    on signals, etc.  We'd better not have left any breakpoints
    in the program or it'll die when it hits one.  */
 static void
-procfs_detach (struct target_ops *ops, const char *args, int from_tty)
+procfs_detach (struct target_ops *ops, int from_tty)
 {
-  int siggnal = 0;
   int pid;
 
   target_announce_detach ();
 
-  if (args)
-    siggnal = atoi (args);
-
   if (siggnal)
-    SignalKill (nto_node (), ptid_get_pid (inferior_ptid), 0, siggnal, 0, 0);
+    SignalKill (nto_node (), ptid_get_pid (inferior_ptid), 0, 0, 0, 0);
 
   close (ctl_fd);
   ctl_fd = -1;
diff --git a/gdb/procfs.c b/gdb/procfs.c
index 888dc69..f6f9ab0 100644
--- a/gdb/procfs.c
+++ b/gdb/procfs.c
@@ -1924,14 +1924,10 @@  procfs_attach (struct target_ops *ops, const char *args, int from_tty)
 }
 
 static void
-procfs_detach (struct target_ops *ops, const char *args, int from_tty)
+procfs_detach (struct target_ops *ops, int from_tty)
 {
-  int sig = 0;
   int pid = ptid_get_pid (inferior_ptid);
 
-  if (args)
-    sig = atoi (args);
-
   if (from_tty)
     {
       const char *exec_file;
@@ -1945,7 +1941,7 @@  procfs_detach (struct target_ops *ops, const char *args, int from_tty)
       gdb_flush (gdb_stdout);
     }
 
-  do_detach (sig);
+  do_detach (0);
 
   inferior_ptid = null_ptid;
   detach_inferior (pid);
diff --git a/gdb/record.c b/gdb/record.c
index 5b554d4..6e1af91 100644
--- a/gdb/record.c
+++ b/gdb/record.c
@@ -187,7 +187,7 @@  record_disconnect (struct target_ops *t, const char *args, int from_tty)
 /* See record.h.  */
 
 void
-record_detach (struct target_ops *t, const char *args, int from_tty)
+record_detach (struct target_ops *t, int from_tty)
 {
   gdb_assert (t->to_stratum == record_stratum);
 
@@ -196,7 +196,7 @@  record_detach (struct target_ops *t, const char *args, int from_tty)
   record_stop (t);
   record_unpush (t);
 
-  target_detach (args, from_tty);
+  target_detach (from_tty);
 }
 
 /* See record.h.  */
diff --git a/gdb/record.h b/gdb/record.h
index 3fc17e4..bee1142 100644
--- a/gdb/record.h
+++ b/gdb/record.h
@@ -88,7 +88,7 @@  extern void record_goto (const char *arg);
 extern void record_disconnect (struct target_ops *, const char *, int);
 
 /* The default "to_detach" target method for record targets.  */
-extern void record_detach (struct target_ops *, const char *, int);
+extern void record_detach (struct target_ops *, int);
 
 /* The default "to_mourn_inferior" target method for record targets.  */
 extern void record_mourn_inferior (struct target_ops *);
diff --git a/gdb/remote-sim.c b/gdb/remote-sim.c
index a684d32..8eaadcb 100644
--- a/gdb/remote-sim.c
+++ b/gdb/remote-sim.c
@@ -77,8 +77,7 @@  static void gdbsim_open (const char *args, int from_tty);
 
 static void gdbsim_close (struct target_ops *self);
 
-static void gdbsim_detach (struct target_ops *ops, const char *args,
-			   int from_tty);
+static void gdbsim_detach (struct target_ops *ops, int from_tty);
 
 static void gdbsim_prepare_to_store (struct target_ops *self,
 				     struct regcache *regcache);
@@ -815,17 +814,16 @@  gdbsim_close (struct target_ops *self)
 /* Takes a program previously attached to and detaches it.
    The program may resume execution (some targets do, some don't) and will
    no longer stop on signals, etc.  We better not have left any breakpoints
-   in the program or it'll die when it hits one.  ARGS is arguments
-   typed by the user (e.g. a signal to send the process).  FROM_TTY
-   says whether to be verbose or not.  */
+   in the program or it'll die when it hits one.  FROM_TTY says whether to be
+   verbose or not.  */
 /* Terminate the open connection to the remote debugger.
    Use this when you want to detach and do something else with your gdb.  */
 
 static void
-gdbsim_detach (struct target_ops *ops, const char *args, int from_tty)
+gdbsim_detach (struct target_ops *ops, int from_tty)
 {
   if (remote_debug)
-    fprintf_unfiltered (gdb_stdlog, "gdbsim_detach: args \"%s\"\n", args);
+    fprintf_unfiltered (gdb_stdlog, "gdbsim_detach\n");
 
   unpush_target (ops);		/* calls gdbsim_close to do the real work */
   if (from_tty)
diff --git a/gdb/remote.c b/gdb/remote.c
index 852fdef..3fcd279 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -5125,16 +5125,13 @@  remote_detach_pid (int pid)
    one.  */
 
 static void
-remote_detach_1 (const char *args, int from_tty)
+remote_detach_1 (int from_tty)
 {
   int pid = ptid_get_pid (inferior_ptid);
   struct remote_state *rs = get_remote_state ();
   struct thread_info *tp = find_thread_ptid (inferior_ptid);
   int is_fork_parent;
 
-  if (args)
-    error (_("Argument given to \"detach\" when remotely debugging."));
-
   if (!target_has_execution)
     error (_("No process to detach from."));
 
@@ -5164,15 +5161,15 @@  remote_detach_1 (const char *args, int from_tty)
 }
 
 static void
-remote_detach (struct target_ops *ops, const char *args, int from_tty)
+remote_detach (struct target_ops *ops, int from_tty)
 {
-  remote_detach_1 (args, from_tty);
+  remote_detach_1 (from_tty);
 }
 
 static void
-extended_remote_detach (struct target_ops *ops, const char *args, int from_tty)
+extended_remote_detach (struct target_ops *ops, int from_tty)
 {
-  remote_detach_1 (args, from_tty);
+  remote_detach_1 (from_tty);
 }
 
 /* Target follow-fork function for remote targets.  On entry, and
diff --git a/gdb/sol-thread.c b/gdb/sol-thread.c
index 5f07a3c..4765ff3 100644
--- a/gdb/sol-thread.c
+++ b/gdb/sol-thread.c
@@ -348,14 +348,14 @@  lwp_to_thread (ptid_t lwp)
    program was started via the normal ptrace (PTRACE_TRACEME).  */
 
 static void
-sol_thread_detach (struct target_ops *ops, const char *args, int from_tty)
+sol_thread_detach (struct target_ops *ops, int from_tty)
 {
   struct target_ops *beneath = find_target_beneath (ops);
 
   sol_thread_active = 0;
   inferior_ptid = pid_to_ptid (ptid_get_pid (main_ph.ptid));
   unpush_target (ops);
-  beneath->to_detach (beneath, args, from_tty);
+  beneath->to_detach (beneath, from_tty);
 }
 
 /* Resume execution of process PTID.  If STEP is nozero, then just
diff --git a/gdb/target-delegates.c b/gdb/target-delegates.c
index aaf11d8..6bb7d7f 100644
--- a/gdb/target-delegates.c
+++ b/gdb/target-delegates.c
@@ -28,28 +28,26 @@  debug_post_attach (struct target_ops *self, int arg1)
 }
 
 static void
-delegate_detach (struct target_ops *self, const char *arg1, int arg2)
+delegate_detach (struct target_ops *self, int arg1)
 {
   self = self->beneath;
-  self->to_detach (self, arg1, arg2);
+  self->to_detach (self, arg1);
 }
 
 static void
-tdefault_detach (struct target_ops *self, const char *arg1, int arg2)
+tdefault_detach (struct target_ops *self, int arg1)
 {
 }
 
 static void
-debug_detach (struct target_ops *self, const char *arg1, int arg2)
+debug_detach (struct target_ops *self, int arg1)
 {
   fprintf_unfiltered (gdb_stdlog, "-> %s->to_detach (...)\n", debug_target.to_shortname);
-  debug_target.to_detach (&debug_target, arg1, arg2);
+  debug_target.to_detach (&debug_target, arg1);
   fprintf_unfiltered (gdb_stdlog, "<- %s->to_detach (", debug_target.to_shortname);
   target_debug_print_struct_target_ops_p (&debug_target);
   fputs_unfiltered (", ", gdb_stdlog);
-  target_debug_print_const_char_p (arg1);
-  fputs_unfiltered (", ", gdb_stdlog);
-  target_debug_print_int (arg2);
+  target_debug_print_int (arg1);
   fputs_unfiltered (")\n", gdb_stdlog);
 }
 
diff --git a/gdb/target.c b/gdb/target.c
index 767a2ad..728cab8 100644
--- a/gdb/target.c
+++ b/gdb/target.c
@@ -2108,7 +2108,7 @@  dispose_inferior (struct inferior *inf, void *args)
       if (target_has_execution)
 	target_kill ();
       else
-	target_detach (NULL, 0);
+	target_detach (0);
     }
 
   return 0;
@@ -2141,10 +2141,10 @@  target_preopen (int from_tty)
   target_pre_inferior (from_tty);
 }
 
-/* Detach a target after doing deferred register stores.  */
+/* See target.h.  */
 
 void
-target_detach (const char *args, int from_tty)
+target_detach (int from_tty)
 {
   if (gdbarch_has_global_breakpoints (target_gdbarch ()))
     /* Don't remove global breakpoints here.  They're removed on
@@ -2157,7 +2157,7 @@  target_detach (const char *args, int from_tty)
 
   prepare_for_detach ();
 
-  current_target.to_detach (&current_target, args, from_tty);
+  current_target.to_detach (&current_target, from_tty);
 }
 
 void
diff --git a/gdb/target.h b/gdb/target.h
index f3774a2..efd0311 100644
--- a/gdb/target.h
+++ b/gdb/target.h
@@ -440,7 +440,7 @@  struct target_ops
     void (*to_attach) (struct target_ops *ops, const char *, int);
     void (*to_post_attach) (struct target_ops *, int)
       TARGET_DEFAULT_IGNORE ();
-    void (*to_detach) (struct target_ops *ops, const char *, int)
+    void (*to_detach) (struct target_ops *ops, int)
       TARGET_DEFAULT_IGNORE ();
     void (*to_disconnect) (struct target_ops *, const char *, int)
       TARGET_DEFAULT_NORETURN (tcomplain ());
@@ -1323,11 +1323,10 @@  extern void target_announce_detach (int from_tty);
 /* Takes a program previously attached to and detaches it.
    The program may resume execution (some targets do, some don't) and will
    no longer stop on signals, etc.  We better not have left any breakpoints
-   in the program or it'll die when it hits one.  ARGS is arguments
-   typed by the user (e.g. a signal to send the process).  FROM_TTY
-   says whether to be verbose or not.  */
+   in the program or it'll die when it hits one.  FROM_TTY says whether to be
+   verbose or not.  */
 
-extern void target_detach (const char *, int);
+extern void target_detach (int from_tty);
 
 /* Disconnect from the current target without resuming it (leaving it
    waiting for a debugger).  */
diff --git a/gdb/top.c b/gdb/top.c
index 3fb113c..61055cf 100644
--- a/gdb/top.c
+++ b/gdb/top.c
@@ -1461,7 +1461,6 @@  set_prompt (const char *s)
 
 struct qt_args
 {
-  char *args;
   int from_tty;
 };
 
@@ -1486,7 +1485,7 @@  kill_or_detach (struct inferior *inf, void *args)
       if (target_has_execution)
 	{
 	  if (inf->attach_flag)
-	    target_detach (qt->args, qt->from_tty);
+	    target_detach (qt->from_tty);
 	  else
 	    target_kill ();
 	}
@@ -1577,7 +1576,6 @@  quit_force (int *exit_arg, int from_tty)
   else if (return_child_result)
     exit_code = return_child_result_value;
 
-  qt.args = NULL;
   qt.from_tty = from_tty;
 
   /* We want to handle any quit errors and exit regardless.  */
diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c
index dc6dbdd..6a6cd08 100644
--- a/gdb/windows-nat.c
+++ b/gdb/windows-nat.c
@@ -1931,7 +1931,7 @@  windows_attach (struct target_ops *ops, const char *args, int from_tty)
 }
 
 static void
-windows_detach (struct target_ops *ops, const char *args, int from_tty)
+windows_detach (struct target_ops *ops, int from_tty)
 {
   int detached = 1;