* inferior.h (target_executing): Delete.
* gdbthread.h (struct thread_info): Add executing_ field.
(set_executing, is_executing): New.
* thread.c (main_thread_executing): New.
(init_thread_list): Clear it and also main_thread_running.
(is_running): Return false if target has no execution.
(any_running, is_executing, set_executing): New.
* top.c: Include "gdbthread.h".
(target_executing): Delete.
(execute_command): Replace target_executing check by any_running.
* event-top.c: Include "gdbthread.h".
(display_gdb_prompt, command_handler): Replace target_executing by
is_running.
* inf-loop.c: Include "gdbthread.h". Don't mark as not executing
here. Replace target_executing by is_running.
* infrun.c (handle_inferior_event): Mark all threads as
not-executing.
* linux-nat.c (linux_nat_resume): Don't mark thread as executing
here.
* stack.c (get_selected_block): Return null if inferior is
executing.
* target.c (target_resume): Mark resumed ptid as executing.
* breakpoint.c (until_break_command): Replace target_executing
check by is_executing.
* remote.c (remote_async_resume): Don't mark inferior as executing
here.
* mi/mi-interp.c (mi_cmd_interpreter_exec): Replace target_executing
by any_running.
* mi/mi-main.c (mi_cmd_exec_interrupt, mi_cmd_execute)
(mi_execute_async_cli_command): Replace target_executing by
is_running.
* frame.c (get_current_frame): Error out if the current thread is
executing.
(has_stack_frames): New.
(get_selected_frame, deprecated_safe_get_selected_frame): Check
has_stack_frames.
* Makefile.in (event-top.o, frame.o, inf-loop.o, top.o): Depend on
$(gdbthread_h).