Commit 
00431a78b28f ("Use thread_info and inferior pointers more
throughout") missed updating some callers, like e.g.,:
 gdb/remote-sim.c: In member function 'virtual void gdbsim_target::mourn_inferior()':
 gdb/remote-sim.c:1198:50: error: cannot convert 'ptid_t' to 'thread_info*' for argument '1' to 'void delete_thread_silent(thread_info*)'
   delete_thread_silent (sim_data->remote_sim_ptid);
 gdb/mygit/src/gdb/procfs.c: In member function ‘virtual void procfs_target::detach(inferior*, int)’:
 gdb/mygit/src/gdb/procfs.c:1931:23: error: invalid conversion from ‘int’ to ‘inferior*’ [-fpermissive]
    detach_inferior (pid);
			 ^
 In file included from gdb/mygit/src/gdb/procfs.c:24:0:
 gdb/mygit/src/gdb/inferior.h:476:13: note:   initializing argument 1 of ‘void detach_inferior(inferior*)’
 etc.
This fixes it.
The delete_thread_silent calls in both go32-nat.c and remote-sim.c are
unnecessary because generic_mourn_inferior calls exit_inferior, which
deletes the inferior's threads.
gdb/ChangeLog:
2018-06-25  Pedro Alves  <palves@redhat.com>
	* windows-nat.c (windows_delete_thread): Use find_thread_ptid and
	pass thread_info pointer to delete_thread.
	(windows_nat_target::detach): Pass inferior pointer to
	detach_inferior.
	* aix-thread.c (sync_threadlists): Pass thread_info pointer to
	delete_thread.
	* bsd-kvm.c (bsd_kvm_target::close): Use discard_all_inferiors.
	* darwin-nat.c (darwin_check_new_threads): Use find_thread_ptid
	and pass a thread_info pointer to delete_thread.
	* fbsd-nat.c (fbsd_nat_target::wait): Use find_thread_ptid and
	pass thread_info pointer to delete_thread.
	* go32-nat.c (go32_nat_target::mourn_inferior): Remove
	delete_thread_silent call.
	* procfs.c (procfs_target::detach): Pass inferior pointer to
	detach_inferior.
	(procfs_target::wait): Pass thread_info pointer to delete_thread.
	* remote-sim.c (gdbsim_target::mourn_inferior): Remove
	delete_thread_silent call.
	* windows-nat.c (windows_delete_thread): Use find_thread_ptid and
	pass thread_info pointer to delete_thread.
	(windows_nat_target::detach): Pass inferior pointer to
	delete_inferior.
 
+2018-06-25  Pedro Alves  <palves@redhat.com>
+
+       * windows-nat.c (windows_delete_thread): Use find_thread_ptid and
+       pass thread_info pointer to delete_thread.
+       (windows_nat_target::detach): Pass inferior pointer to
+       detach_inferior.
+       * aix-thread.c (sync_threadlists): Pass thread_info pointer to
+       delete_thread.
+       * bsd-kvm.c (bsd_kvm_target::close): Use discard_all_inferiors.
+       * darwin-nat.c (darwin_check_new_threads): Use find_thread_ptid
+       and pass a thread_info pointer to delete_thread.
+       * fbsd-nat.c (fbsd_nat_target::wait): Use find_thread_ptid and
+       pass thread_info pointer to delete_thread.
+       * go32-nat.c (go32_nat_target::mourn_inferior): Remove
+       delete_thread_silent call.
+       * procfs.c (procfs_target::detach): Pass inferior pointer to
+       detach_inferior.
+       (procfs_target::wait): Pass thread_info pointer to delete_thread.
+       * remote-sim.c (gdbsim_target::mourn_inferior): Remove
+       delete_thread_silent call.
+       * windows-nat.c (windows_delete_thread): Use find_thread_ptid and
+       pass thread_info pointer to delete_thread.
+       (windows_nat_target::detach): Pass inferior pointer to
+       delete_inferior.
+
 2018-06-22  Alan Hayward  <alan.hayward@arm.com>
 
        * regcache.c (readable_regcache::read_part): Fix asserts.
 
     {
       if (pi == pcount)
        {
-         delete_thread (gbuf[gi]->ptid);
+         delete_thread (gbuf[gi]);
          gi++;
        }
       else if (gi == gcount)
            }
          else if (cmp_result > 0)
            {
-             delete_thread (gptid);
+             delete_thread (gbuf[gi]);
              gi++;
            }
          else
 
     }
 
   inferior_ptid = null_ptid;
-  delete_thread_silent (bsd_kvm_ptid);
+  discard_all_inferiors ();
 }
 
 static LONGEST
 
       if (old_ix < old_nbr && (new_ix == new_nbr || new_id > old_id))
        {
          /* A thread was removed.  */
-         delete_thread (ptid_build (inf->pid, 0, old_id));
+         struct thread_info *thr
+           = find_thread_ptid (ptid_build (inf->pid, 0, old_id));
+         delete_thread (thr);
          kret = mach_port_deallocate (gdb_task, old_id);
          MACH_CHECK_ERROR (kret);
          old_ix++;
 
                 threads might be skipped during post_attach that
                 have not yet reported their PL_FLAG_EXITED event.
                 Ignore EXITED events for an unknown LWP.  */
-             if (in_thread_list (wptid))
+             thread_info *thr = find_thread_ptid (wptid);
+             if (thr != nullptr)
                {
                  if (debug_fbsd_lwp)
                    fprintf_unfiltered (gdb_stdlog,
                  if (print_thread_events)
                    printf_unfiltered (_("[%s exited]\n"), target_pid_to_str
                                       (wptid));
-                 delete_thread (wptid);
+                 delete_thread (thr);
                }
              if (ptrace (PT_CONTINUE, pid, (caddr_t) 1, 0) == -1)
                perror_with_name (("ptrace"));
 
 
   ptid = inferior_ptid;
   inferior_ptid = null_ptid;
-  delete_thread_silent (ptid);
   prog_has_started = 0;
 
   generic_mourn_inferior ();
 
   do_detach ();
 
   inferior_ptid = null_ptid;
-  detach_inferior (pid);
+  detach_inferior (inf);
   maybe_unpush_target ();
 }
 
                    if (print_thread_events)
                      printf_unfiltered (_("[%s exited]\n"),
                                         target_pid_to_str (retval));
-                   delete_thread (retval);
+                   delete_thread (find_thread_ptid (retval));
                    status->kind = TARGET_WAITKIND_SPURIOUS;
                    return retval;
                  }
                    if (print_thread_events)
                      printf_unfiltered (_("[%s exited]\n"),
                                         target_pid_to_str (retval));
-                   delete_thread (retval);
+                   delete_thread (find_thread_ptid (retval));
                    status->kind = TARGET_WAITKIND_SPURIOUS;
                    return retval;
                  }
 
 
   remove_breakpoints ();
   generic_mourn_inferior ();
-  delete_thread_silent (sim_data->remote_sim_ptid);
 }
 
 /* Pass the command argument through to the simulator verbatim.  The
 
   else if (print_thread_events && id != main_thread_id)
     printf_unfiltered (_("[%s exited with code %u]\n"),
                       target_pid_to_str (ptid), (unsigned) exit_code);
-  delete_thread (ptid);
+  delete_thread (find_thread_ptid (ptid));
 
   for (th = &thread_head;
        th->next != NULL && th->next->id != id;
 
   x86_cleanup_dregs ();
   inferior_ptid = null_ptid;
-  detach_inferior (current_event.dwProcessId);
+  detach_inferior (inf);
 
   maybe_unpush_target ();
 }