[PATCHv2 5/6] gdb: add inferior-specific breakpoints and watchpoints

[Andrew Burgess <aburgess@redhat.com>]

This commit extends the breakpoint mechanism to allow for inferior
specific breakpoints (and watchpoints).

As GDB gains better support for multiple connections, and so for
running multiple (possibly unrelated) inferiors, then it is not hard
to imagine that a user might wish to create breakpoints that apply to
any thread in a single inferior.  To achieve this currently, the user
would need to create a condition possibly making use of the $_inferior
convenience variable, which, though functional, isn't the most user
friendly.

This commit adds a new 'inferior' keyword that allows for the creation
of inferior specific breakpoints.

Like thread specific breakpoints, the inferior specific breakpoints
are automatically deleted once the inferior in question exits.
---
 gdb/NEWS                                      |   7 +
 gdb/breakpoint.c                              | 171 +++++++++++++---
 gdb/breakpoint.h                              |  10 +-
 gdb/doc/gdb.texinfo                           |  74 ++++++-
 gdb/doc/python.texi                           |  24 ++-
 gdb/dummy-frame.c                             |   1 +
 gdb/elfread.c                                 |   5 +-
 gdb/guile/scm-breakpoint.c                    |   5 +
 gdb/inferior.h                                |  11 ++
 gdb/infrun.c                                  |   2 +
 gdb/linespec.c                                |   4 +-
 gdb/python/py-breakpoint.c                    |  77 ++++++++
 gdb/testsuite/gdb.linespec/cpcompletion.exp   |   4 +-
 gdb/testsuite/gdb.linespec/explicit.exp       |   1 +
 .../gdb.multi/inferior-specific-bp-1.c        |  52 +++++
 .../gdb.multi/inferior-specific-bp-2.c        |  52 +++++
 .../gdb.multi/inferior-specific-bp.exp        | 182 ++++++++++++++++++
 gdb/testsuite/gdb.python/py-breakpoint.exp    |  43 +++++
 gdb/testsuite/lib/completion-support.exp      |   2 +-
 19 files changed, 680 insertions(+), 47 deletions(-)
 create mode 100644 gdb/testsuite/gdb.multi/inferior-specific-bp-1.c
 create mode 100644 gdb/testsuite/gdb.multi/inferior-specific-bp-2.c
 create mode 100644 gdb/testsuite/gdb.multi/inferior-specific-bp.exp

diff --git a/gdb/NEWS b/gdb/NEWS
index fb49f62f7e6..cde9a835b2e 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -18,6 +18,13 @@
   instance of the keyword.  The 'thread' keyword already gave an error
   when used multiple times with the watch command, this remains unchanged.
 
+* Breakpoints can now be inferior-specific.  This is similar to the
+  existing thread-specific breakpoint support.  Breakpoint conditions
+  can include the 'inferior' keyword followed by an inferior id (as
+  displayed in the 'info inferiors' output).  It is invalid to use
+  both the 'inferior' and 'thread' keywords when creating a
+  breakpoint.
+
 * New commands
 
 maintenance print record-instruction [ N ]
diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
index 1400fd49642..a7c7c27017b 100644
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -96,7 +96,7 @@ static void create_breakpoints_sal (struct gdbarch *,
 				    gdb::unique_xmalloc_ptr<char>,
 				    gdb::unique_xmalloc_ptr<char>,
 				    enum bptype,
-				    enum bpdisp, int, int,
+				    enum bpdisp, int, int, int,
 				    int,
 				    int, int, int, unsigned);
 
@@ -1462,11 +1462,28 @@ breakpoint_set_thread (struct breakpoint *b, int thread)
 {
   int old_thread = b->thread;
 
+  gdb_assert (thread == -1 || b->inferior == -1);
+
   b->thread = thread;
   if (old_thread != thread)
     gdb::observers::breakpoint_modified.notify (b);
 }
 
+/* Set the inferior for breakpoint B to INFERIOR.  If INFERIOR is -1, make
+   the breakpoint work for any inferior.  */
+
+void
+breakpoint_set_inferior (struct breakpoint *b, int inferior)
+{
+  int old_inferior = b->inferior;
+
+  gdb_assert (inferior == -1 || b->thread == -1);
+
+  b->inferior = inferior;
+  if (old_inferior != inferior)
+    gdb::observers::breakpoint_modified.notify (b);
+}
+
 /* Set the task for this breakpoint.  If TASK is 0, make the
    breakpoint work for any task.  */
 
@@ -3152,6 +3169,12 @@ insert_breakpoint_locations (void)
 	  && !valid_global_thread_id (bl->owner->thread))
 	continue;
 
+      /* Or inferior specific breakpoints if the inferior no longer
+	 exists.  */
+      if (bl->owner->inferior != -1
+	  && !valid_global_inferior_id (bl->owner->inferior))
+	continue;
+
       switch_to_program_space_and_thread (bl->pspace);
 
       /* For targets that support global breakpoints, there's no need
@@ -3256,6 +3279,31 @@ Thread-specific breakpoint %d deleted - thread %s no longer in the thread list.\
     }
 }
 
+/* Called when inferior INF has exited.  Remove per-inferior breakpoints.  */
+
+static void
+remove_inferior_breakpoints (struct inferior *inf)
+{
+  for (breakpoint *b : all_breakpoints_safe ())
+    {
+      if (b->inferior == inf->num && user_breakpoint_p (b))
+	{
+	  /* Tell the user the breakpoint has been deleted.  But only for
+	     breakpoints that would not normally have been deleted at the
+	     next stop anyway.  */
+	  if (b->disposition != disp_del
+	      && b->disposition != disp_del_at_next_stop)
+	    gdb_printf (_("\
+Inferior-specific breakpoint %d deleted - inferior %d has exited.\n"),
+			b->number, inf->num);
+
+	  /* Hide it from the user and mark it for deletion.  */
+	  b->number = 0;
+	  b->disposition = disp_del_at_next_stop;
+       }
+    }
+}
+
 /* See breakpoint.h.  */
 
 void
@@ -5465,6 +5513,7 @@ bpstat_check_breakpoint_conditions (bpstat *bs, thread_info *thread)
      evaluating the condition if this isn't the specified
      thread/task.  */
   if ((b->thread != -1 && b->thread != thread->global_num)
+      || (b->inferior != -1 && b->inferior != thread->inf->num)
       || (b->task != 0 && b->task != ada_get_task_number (thread)))
     {
       infrun_debug_printf ("incorrect thread or task, not stopping");
@@ -6481,6 +6530,8 @@ print_one_breakpoint_location (struct breakpoint *b,
 	uiout->field_signed ("thread", b->thread);
       else if (b->task != 0)
 	uiout->field_signed ("task", b->task);
+      else if (b->inferior != -1)
+	uiout->field_signed ("inferior", b->inferior);
     }
 
   uiout->text ("\n");
@@ -6543,6 +6594,13 @@ print_one_breakpoint_location (struct breakpoint *b,
       uiout->text ("\n");
     }
 
+  if (!part_of_multiple && b->inferior != -1)
+    {
+      uiout->text ("\tstop only in inferior ");
+      uiout->field_signed ("inferior", b->inferior);
+      uiout->text ("\n");
+    }
+
   if (!part_of_multiple)
     {
       if (b->hit_count)
@@ -7516,7 +7574,10 @@ delete_longjmp_breakpoint (int thread)
     if (b->type == bp_longjmp || b->type == bp_exception)
       {
 	if (b->thread == thread)
-	  delete_breakpoint (b);
+	  {
+	    gdb_assert (b->inferior == -1);
+	    delete_breakpoint (b);
+	  }
       }
 }
 
@@ -7527,7 +7588,10 @@ delete_longjmp_breakpoint_at_next_stop (int thread)
     if (b->type == bp_longjmp || b->type == bp_exception)
       {
 	if (b->thread == thread)
-	  b->disposition = disp_del_at_next_stop;
+	  {
+	    gdb_assert (b->inferior == -1);
+	    b->disposition = disp_del_at_next_stop;
+	  }
       }
 }
 
@@ -7580,6 +7644,7 @@ check_longjmp_breakpoint_for_call_dummy (struct thread_info *tp)
   ALL_BREAKPOINTS_SAFE (b, b_tmp)
     if (b->type == bp_longjmp_call_dummy && b->thread == tp->global_num)
       {
+	gdb_assert (b->inferior == -1);
 	struct breakpoint *dummy_b = b->related_breakpoint;
 
 	/* Find the bp_call_dummy breakpoint in the list of breakpoints
@@ -8412,7 +8477,8 @@ code_breakpoint::code_breakpoint (struct gdbarch *gdbarch_,
 				  gdb::unique_xmalloc_ptr<char> cond_string_,
 				  gdb::unique_xmalloc_ptr<char> extra_string_,
 				  enum bpdisp disposition_,
-				  int thread_, int task_, int ignore_count_,
+				  int thread_, int task_, int inferior_,
+				  int ignore_count_,
 				  int from_tty,
 				  int enabled_, unsigned flags,
 				  int display_canonical_)
@@ -8438,6 +8504,11 @@ code_breakpoint::code_breakpoint (struct gdbarch *gdbarch_,
 
   thread = thread_;
   task = task_;
+  inferior = inferior_;
+
+  /* A breakpoint can be thread specific, or inferior specific, but not
+     both.  This should be checked when the breakpoint condition is parsed.  */
+  gdb_assert (thread == -1 || inferior == -1);
 
   cond_string = std::move (cond_string_);
   extra_string = std::move (extra_string_);
@@ -8539,7 +8610,7 @@ create_breakpoint_sal (struct gdbarch *gdbarch,
 		       gdb::unique_xmalloc_ptr<char> cond_string,
 		       gdb::unique_xmalloc_ptr<char> extra_string,
 		       enum bptype type, enum bpdisp disposition,
-		       int thread, int task, int ignore_count,
+		       int thread, int task, int inferior, int ignore_count,
 		       int from_tty,
 		       int enabled, int internal, unsigned flags,
 		       int display_canonical)
@@ -8553,7 +8624,7 @@ create_breakpoint_sal (struct gdbarch *gdbarch,
 				std::move (cond_string),
 				std::move (extra_string),
 				disposition,
-				thread, task, ignore_count,
+				thread, task, inferior, ignore_count,
 				from_tty,
 				enabled, flags,
 				display_canonical);
@@ -8582,7 +8653,8 @@ create_breakpoints_sal (struct gdbarch *gdbarch,
 			gdb::unique_xmalloc_ptr<char> cond_string,
 			gdb::unique_xmalloc_ptr<char> extra_string,
 			enum bptype type, enum bpdisp disposition,
-			int thread, int task, int ignore_count,
+			int thread, int task, int inferior,
+			int ignore_count,
 			int from_tty,
 			int enabled, int internal, unsigned flags)
 {
@@ -8606,7 +8678,7 @@ create_breakpoints_sal (struct gdbarch *gdbarch,
 			     std::move (cond_string),
 			     std::move (extra_string),
 			     type, disposition,
-			     thread, task, ignore_count,
+			     thread, task, inferior, ignore_count,
 			     from_tty, enabled, internal, flags,
 			     canonical->special_display);
     }
@@ -8736,21 +8808,26 @@ check_fast_tracepoint_sals (struct gdbarch *gdbarch,
     }
 }
 
-/* Given TOK, a string specification of condition and thread, as
-   accepted by the 'break' command, extract the condition
-   string and thread number and set *COND_STRING and *THREAD.
-   PC identifies the context at which the condition should be parsed.
-   If no condition is found, *COND_STRING is set to NULL.
-   If no thread is found, *THREAD is set to -1.  */
+/* Given TOK, a string specification of condition and thread, as accepted
+   by the 'break' command, extract the condition string into *COND_STRING.
+   If no condition string is found then *COND_STRING is set to nullptr.
+
+   If the breakpoint specification has an associated thread, task, or
+   inferior, these are extracted into *THREAD, *TASK, and *INFERIOR
+   respectively, otherwise these arguments are set to -1 (for THREAD and
+   INFERIOR) or 0 (for TASK).
+
+   PC identifies the context at which the condition should be parsed.  */
 
 static void
 find_condition_and_thread (const char *tok, CORE_ADDR pc,
 			   gdb::unique_xmalloc_ptr<char> *cond_string,
-			   int *thread, int *task,
+			   int *thread, int *inferior, int *task,
 			   gdb::unique_xmalloc_ptr<char> *rest)
 {
   cond_string->reset ();
   *thread = -1;
+  *inferior = -1;
   *task = 0;
   rest->reset ();
   bool force = false;
@@ -8767,7 +8844,7 @@ find_condition_and_thread (const char *tok, CORE_ADDR pc,
       if ((*tok == '"' || *tok == ',') && rest)
 	{
 	  rest->reset (savestring (tok, strlen (tok)));
-	  return;
+	  break;
 	}
 
       end_tok = skip_to_space (tok);
@@ -8811,6 +8888,18 @@ find_condition_and_thread (const char *tok, CORE_ADDR pc,
 	  *thread = thr->global_num;
 	  tok = tmptok;
 	}
+      else if (toklen >= 1 && strncmp (tok, "inferior", toklen) == 0)
+	{
+	  char *tmptok;
+
+	  tok = end_tok + 1;
+	  *inferior = strtol (tok, &tmptok, 0);
+	  if (tok == tmptok)
+	    error (_("Junk after inferior keyword."));
+	  if (!valid_global_inferior_id (*inferior))
+	    error (_("Unknown inferior number %d."), *inferior);
+	  tok = tmptok;
+	}
       else if (toklen >= 1 && strncmp (tok, "task", toklen) == 0)
 	{
 	  char *tmptok;
@@ -8829,11 +8918,15 @@ find_condition_and_thread (const char *tok, CORE_ADDR pc,
       else if (rest)
 	{
 	  rest->reset (savestring (tok, strlen (tok)));
-	  return;
+	  break;
 	}
       else
 	error (_("Junk at end of arguments."));
     }
+
+  if (*thread != -1 && *inferior != -1)
+    error (_("Cannot have both 'thread' and 'inferior' conditions on "
+	     "a breakpoint"));
 }
 
 /* Call 'find_condition_and_thread' for each sal in SALS until a parse
@@ -8845,7 +8938,7 @@ static void
 find_condition_and_thread_for_sals (const std::vector<symtab_and_line> &sals,
 				    const char *input,
 				    gdb::unique_xmalloc_ptr<char> *cond_string,
-				    int *thread, int *task,
+				    int *thread, int *inferior, int *task,
 				    gdb::unique_xmalloc_ptr<char> *rest)
 {
   int num_failures = 0;
@@ -8853,6 +8946,7 @@ find_condition_and_thread_for_sals (const std::vector<symtab_and_line> &sals,
     {
       gdb::unique_xmalloc_ptr<char> cond;
       int thread_id = 0;
+      int inferior_id = 0;
       int task_id = 0;
       gdb::unique_xmalloc_ptr<char> remaining;
 
@@ -8865,9 +8959,10 @@ find_condition_and_thread_for_sals (const std::vector<symtab_and_line> &sals,
       try
 	{
 	  find_condition_and_thread (input, sal.pc, &cond, &thread_id,
-				     &task_id, &remaining);
+				     &inferior_id, &task_id, &remaining);
 	  *cond_string = std::move (cond);
 	  *thread = thread_id;
+	  *inferior = inferior_id;
 	  *task = task_id;
 	  *rest = std::move (remaining);
 	  break;
@@ -8969,6 +9064,7 @@ create_breakpoint (struct gdbarch *gdbarch,
   struct linespec_result canonical;
   bool pending = false;
   int task = 0;
+  int inferior = -1;
   int prev_bkpt_count = breakpoint_count;
 
   gdb_assert (ops != NULL);
@@ -9046,7 +9142,8 @@ create_breakpoint (struct gdbarch *gdbarch,
 	  const linespec_sals &lsal = canonical.lsals[0];
 
 	  find_condition_and_thread_for_sals (lsal.sals, extra_string,
-					      &cond, &thread, &task, &rest);
+					      &cond, &thread, &inferior,
+					      &task, &rest);
 	  cond_string_copy = std::move (cond);
 	  extra_string_copy = std::move (rest);
 	}
@@ -9096,7 +9193,7 @@ create_breakpoint (struct gdbarch *gdbarch,
 				   std::move (extra_string_copy),
 				   type_wanted,
 				   tempflag ? disp_del : disp_donttouch,
-				   thread, task, ignore_count,
+				   thread, task, inferior, ignore_count,
 				   from_tty, enabled, internal, flags);
     }
   else
@@ -10036,6 +10133,7 @@ watch_command_1 (const char *arg, int accessflag, int from_tty,
   const char *cond_end = NULL;
   enum bptype bp_type;
   int thread = -1;
+  int inferior = -1;
   /* Flag to indicate whether we are going to use masks for
      the hardware watchpoint.  */
   bool use_mask = false;
@@ -10076,6 +10174,10 @@ watch_command_1 (const char *arg, int accessflag, int from_tty,
 	  tok++;
 	  toklen = end_tok - tok + 1;
 
+	  if (thread != -1 && inferior != -1)
+	    error (_("Cannot have both 'thread' and 'inferior' conditions "
+		     "on a watchpoint"));
+
 	  if (toklen == 6 && startswith (tok, "thread"))
 	    {
 	      struct thread_info *thr;
@@ -10089,10 +10191,8 @@ watch_command_1 (const char *arg, int accessflag, int from_tty,
 
 	      /* Extract the thread ID from the next token.  */
 	      thr = parse_thread_id (value_start, &endp);
-
-	      /* Check if the user provided a valid thread ID.  */
-	      if (*endp != ' ' && *endp != '\t' && *endp != '\0')
-		invalid_thread_id_error (value_start);
+	      if (value_start == endp)
+		error (_("Junk after thread keyword."));
 
 	      thread = thr->global_num;
 	    }
@@ -10109,6 +10209,16 @@ watch_command_1 (const char *arg, int accessflag, int from_tty,
 	      if (!valid_task_id (task))
 		error (_("Unknown task %d."), task);
 	    }
+	  else if (toklen == 8 && startswith (tok, "inferior"))
+	    {
+	      char *tmp;
+
+	      inferior = strtol (value_start, &tmp, 0);
+	      if (tmp == value_start)
+		error (_("Junk after inferior keyword."));
+	      if (!valid_global_inferior_id (inferior))
+		error (_("Unknown inferior number %d."), inferior);
+	    }
 	  else if (toklen == 4 && startswith (tok, "mask"))
 	    {
 	      /* We've found a "mask" token, which means the user wants to
@@ -10279,6 +10389,7 @@ watch_command_1 (const char *arg, int accessflag, int from_tty,
     w.reset (new watchpoint (nullptr, bp_type));
 
   w->thread = thread;
+  w->inferior = inferior;
   w->task = task;
   w->disposition = disp_donttouch;
   w->pspace = current_program_space;
@@ -12189,7 +12300,8 @@ strace_marker_create_breakpoints_sal (struct gdbarch *gdbarch,
 				      enum bptype type_wanted,
 				      enum bpdisp disposition,
 				      int thread,
-				      int task, int ignore_count,
+				      int task, int inferior,
+				      int ignore_count,
 				      int from_tty, int enabled,
 				      int internal, unsigned flags)
 {
@@ -12215,7 +12327,7 @@ strace_marker_create_breakpoints_sal (struct gdbarch *gdbarch,
 			 std::move (cond_string),
 			 std::move (extra_string),
 			 disposition,
-			 thread, task, ignore_count,
+			 thread, task, inferior, ignore_count,
 			 from_tty, enabled, flags,
 			 canonical->special_display));
 
@@ -12848,10 +12960,11 @@ code_breakpoint::location_spec_to_sals (location_spec *locspec,
       if (condition_not_parsed && extra_string != NULL)
 	{
 	  gdb::unique_xmalloc_ptr<char> local_cond, local_extra;
-	  int local_thread, local_task;
+	  int local_thread, local_task, local_inferior;
 
 	  find_condition_and_thread_for_sals (sals, extra_string.get (),
 					      &local_cond, &local_thread,
+					      &local_inferior,
 					      &local_task, &local_extra);
 	  gdb_assert (cond_string == nullptr);
 	  if (local_cond != nullptr)
@@ -14937,4 +15050,6 @@ This is useful for formatted output in user-defined commands."));
 					   "breakpoint");
   gdb::observers::thread_exit.attach (remove_threaded_breakpoints,
 				      "breakpoint");
+  gdb::observers::inferior_exit.attach (remove_inferior_breakpoints,
+					"breakpoint");
 }
diff --git a/gdb/breakpoint.h b/gdb/breakpoint.h
index 399bd037977..0ec7c4fe8e1 100644
--- a/gdb/breakpoint.h
+++ b/gdb/breakpoint.h
@@ -584,7 +584,7 @@ struct breakpoint_ops
 				  struct linespec_result *,
 				  gdb::unique_xmalloc_ptr<char>,
 				  gdb::unique_xmalloc_ptr<char>,
-				  enum bptype, enum bpdisp, int, int,
+				  enum bptype, enum bpdisp, int, int, int,
 				  int, int, int, int, unsigned);
 };
 
@@ -802,6 +802,10 @@ struct breakpoint
      care.  */
   int thread = -1;
 
+  /* Inferior number for inferior-specific breakpoint, or -1 if this
+     breakpoint is for all inferiors.  */
+  int inferior = -1;
+
   /* Ada task number for task-specific breakpoint, or 0 if don't
      care.  */
   int task = 0;
@@ -857,7 +861,7 @@ struct code_breakpoint : public breakpoint
 		   gdb::unique_xmalloc_ptr<char> cond_string,
 		   gdb::unique_xmalloc_ptr<char> extra_string,
 		   enum bpdisp disposition,
-		   int thread, int task, int ignore_count,
+		   int thread, int task, int inferior, int ignore_count,
 		   int from_tty,
 		   int enabled, unsigned flags,
 		   int display_canonical);
@@ -1673,6 +1677,8 @@ extern void breakpoint_set_silent (struct breakpoint *b, int silent);
 
 extern void breakpoint_set_thread (struct breakpoint *b, int thread);
 
+extern void breakpoint_set_inferior (struct breakpoint *b, int inferior);
+
 extern void breakpoint_set_task (struct breakpoint *b, int task);
 
 /* Clear the "inserted" flag in all breakpoints.  */
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 9c0018ea5c1..6f07193af77 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -3504,6 +3504,58 @@
 space as a result of inferior 1 having executed a @code{vfork} call.
 @end table
 
+@menu
+* Inferior-Specific Breakpoints::	Controlling breakpoints
+@end menu
+
+@node Inferior-Specific Breakpoints
+@subsection Inferior-Specific Breakpoints
+
+When debugging multiple inferiors, you can choose whether to set
+breakpoints for all inferiors, or for a particular inferior.
+
+@table @code
+@cindex breakpoints and inferiors
+@cindex inferior-specific breakpoints
+@kindex break @dots{} inferior @var{inferior-id}
+@item break @var{locspec} inferior @var{inferior-id}
+@itemx break @var{locspec} inferior @var{inferior-id} if @dots{}
+@var{locspec} specifies a code location or locations in your program.
+@xref{Location Specifications}, for details.
+
+Use the qualifier @samp{inferior @var{inferior-id}} with a breakpoint
+command to specify that you only want @value{GDBN} to stop when a
+particular inferior reaches this breakpoint.  The @var{inferior-id}
+specifier is one of the inferior identifiers assigned by @value{GDBN},
+shown in the first column of the @samp{info inferiors} output.
+
+If you do not specify @samp{inferior @var{inferior-id}} when you set a
+breakpoint, the breakpoint applies to @emph{all} inferiors of your
+program.
+
+You can use the @code{inferior} qualifier on conditional breakpoints as
+well; in this case, place @samp{inferior @var{inferior-id}} before or
+after the breakpoint condition, like this:
+
+@smallexample
+(@value{GDBP}) break frik.c:13 inferior 2 if bartab > lim
+@end smallexample
+@end table
+
+Inferior-specific breakpoints are automatically deleted when
+@value{GDBN} detects that the corresponding inferior has exited.  For
+example:
+
+@smallexample
+(@value{GDBP}) c
+Inferior-specific breakpoint 3 deleted - inferior 2 has exited.
+@end smallexample
+
+A breakpoint can't be both inferior-specific and thread-specific
+(@pxref{Thread-Specific Breakpoints}); using both the @code{inferior}
+and @code{thread} keywords when creating a breakpoint will give an
+error.
+
 @node Threads
 @section Debugging Programs with Multiple Threads
 
@@ -4466,8 +4518,9 @@
 situation.
 
 It is also possible to insert a breakpoint that will stop the program
-only if a specific thread (@pxref{Thread-Specific Breakpoints})
-or a specific task (@pxref{Ada Tasks}) hits that breakpoint.
+only if a specific thread (@pxref{Thread-Specific Breakpoints}),
+specific inferior (@pxref{Inferior-Specific Breakpoints}), or a
+specific task (@pxref{Ada Tasks}) hits that breakpoint.
 
 @item break
 When called without any arguments, @code{break} sets a breakpoint at
@@ -4983,7 +5036,7 @@
 
 @table @code
 @kindex watch
-@item watch @r{[}-l@r{|}-location@r{]} @var{expr} @r{[}thread @var{thread-id}@r{]} @r{[}mask @var{maskvalue}@r{]} @r{[}task @var{task-id}@r{]}
+@item watch @r{[}-l@r{|}-location@r{]} @var{expr} @r{[}thread @var{thread-id}@r{]} @r{[}inferior @var{inferior-id}@r{]} @r{[}mask @var{maskvalue}@r{]} @r{[}task @var{task-id}@r{]}
 Set a watchpoint for an expression.  @value{GDBN} will break when the
 expression @var{expr} is written into by the program and its value
 changes.  The simplest (and the most popular) use of this command is
@@ -5000,8 +5053,10 @@
 that watchpoints restricted to a single thread in this way only work
 with Hardware Watchpoints.
 
-Similarly, if the @code{task} argument is given, then the watchpoint
-will be specific to the indicated Ada task (@pxref{Ada Tasks}).
+Similarly, if the @code{inferior} argument is given, then the
+watchpoint will trigger only for the specific inferior, or if the
+@code{task} argument is given, then the watchpoint will be specific to
+the indicated Ada task (@pxref{Ada Tasks}).
 
 Ordinarily a watchpoint respects the scope of variables in @var{expr}
 (see below).  The @code{-location} argument tells @value{GDBN} to
@@ -5030,12 +5085,12 @@
 @end smallexample
 
 @kindex rwatch
-@item rwatch @r{[}-l@r{|}-location@r{]} @var{expr} @r{[}thread @var{thread-id}@r{]} @r{[}mask @var{maskvalue}@r{]}
+@item rwatch @r{[}-l@r{|}-location@r{]} @var{expr} @r{[}thread @var{thread-id}@r{]} @r{[}inferior @var{inferior-id}@r{]} @r{[}mask @var{maskvalue}@r{]}
 Set a watchpoint that will break when the value of @var{expr} is read
 by the program.
 
 @kindex awatch
-@item awatch @r{[}-l@r{|}-location@r{]} @var{expr} @r{[}thread @var{thread-id}@r{]} @r{[}mask @var{maskvalue}@r{]}
+@item awatch @r{[}-l@r{|}-location@r{]} @var{expr} @r{[}thread @var{thread-id}@r{]} @r{[}inferior @var{inferior-id}@r{]} @r{[}mask @var{maskvalue}@r{]}
 Set a watchpoint that will break when @var{expr} is either read from
 or written into by the program.
 
@@ -7318,6 +7373,11 @@
 explictly asks for the thread list with the @code{info threads}
 command.
 
+A breakpoint can't be both thread-specific and inferior-specific
+(@pxref{Inferior-Specific Breakpoints}) using both the @code{thread}
+and @code{inferior} keywords when creating a breakpoint will give an
+error.
+
 @node Interrupted System Calls
 @subsection Interrupted System Calls 
 
diff --git a/gdb/doc/python.texi b/gdb/doc/python.texi
index 7208af3ee7d..5420324ce2c 100644
--- a/gdb/doc/python.texi
+++ b/gdb/doc/python.texi
@@ -3281,7 +3281,10 @@
 A @code{gdb.Inferior} object has the following attributes:
 
 @defvar Inferior.num
-ID of inferior, as assigned by GDB.
+ID of inferior, as assigned by @value{GDBN}.  You can use this to make
+Python breakpoints inferior-specific, for example
+(@pxref{python_breakpoint_inferior,,The Breakpoint.inferior
+attribute}).
 @end defvar
 
 @anchor{gdbpy_inferior_connection}
@@ -6077,9 +6080,22 @@
 
 @anchor{python_breakpoint_thread}
 @defvar Breakpoint.thread
-If the breakpoint is thread-specific, this attribute holds the
-thread's global id.  If the breakpoint is not thread-specific, this
-attribute is @code{None}.  This attribute is writable.
+If the breakpoint is thread-specific (@pxref{Thread-Specific
+Breakpoints}), this attribute holds the thread's global id.  If the
+breakpoint is not thread-specific, this attribute is @code{None}.
+This attribute is writable.
+
+Only one of @code{Breakpoint.thread} or @code{Breakpoint.inferior} can
+be set to a valid id at any time, that is, a breakpoint can be thread
+specific, or inferior specific, but not both.
+@end defvar
+
+@anchor{python_breakpoint_inferior}
+@defvar Breakpoint.inferior
+If the breakpoint is inferior-specific (@pxref{Inferior-Specific
+Breakpoints}), this attribute holds the inferior's id.  If the
+breakpoint is not inferior-specific, this attribute is @code{None}.
+This attribute is writable.
 @end defvar
 
 @defvar Breakpoint.task
diff --git a/gdb/dummy-frame.c b/gdb/dummy-frame.c
index 784ac103eec..ad861d8d87f 100644
--- a/gdb/dummy-frame.c
+++ b/gdb/dummy-frame.c
@@ -132,6 +132,7 @@ pop_dummy_frame_bpt (struct breakpoint *b, struct dummy_frame *dummy)
   if (b->thread == dummy->id.thread->global_num
       && b->disposition == disp_del && b->frame_id == dummy->id.id)
     {
+      gdb_assert (b->inferior == -1);
       while (b->related_breakpoint != b)
 	delete_breakpoint (b->related_breakpoint);
 
diff --git a/gdb/elfread.c b/gdb/elfread.c
index ccee37406c8..cc1b339da75 100644
--- a/gdb/elfread.c
+++ b/gdb/elfread.c
@@ -968,7 +968,10 @@ elf_gnu_ifunc_resolver_stop (code_breakpoint *b)
       if (b_return->thread == thread_id
 	  && b_return->loc->requested_address == prev_pc
 	  && b_return->frame_id == prev_frame_id)
-	break;
+	{
+	  gdb_assert (b_return->inferior == -1);
+	  break;
+	}
     }
 
   if (b_return == b)
diff --git a/gdb/guile/scm-breakpoint.c b/gdb/guile/scm-breakpoint.c
index a7e043d847b..4c6fff070cf 100644
--- a/gdb/guile/scm-breakpoint.c
+++ b/gdb/guile/scm-breakpoint.c
@@ -779,6 +779,11 @@ gdbscm_set_breakpoint_thread_x (SCM self, SCM newvalue)
   else
     SCM_ASSERT_TYPE (0, newvalue, SCM_ARG2, FUNC_NAME, _("integer or #f"));
 
+  if (bp_smob->bp->inferior != -1)
+    scm_misc_error (FUNC_NAME,
+		    _("Cannot have both thread and inferior conditions "
+		      "on a breakpoint"), SCM_EOL);
+
   breakpoint_set_thread (bp_smob->bp, id);
 
   return SCM_UNSPECIFIED;
diff --git a/gdb/inferior.h b/gdb/inferior.h
index 4d001b0ad50..e728a3481ad 100644
--- a/gdb/inferior.h
+++ b/gdb/inferior.h
@@ -787,4 +787,15 @@ extern void print_selected_inferior (struct ui_out *uiout);
 extern void switch_to_inferior_and_push_target
   (inferior *new_inf, bool no_connection, inferior *org_inf);
 
+/* Return true if ID is a valid global inferior number.  */
+
+inline bool
+valid_global_inferior_id (int id)
+{
+  for (inferior *inf : all_inferiors ())
+    if (inf->num == id)
+      return true;
+  return false;
+}
+
 #endif /* !defined (INFERIOR_H) */
diff --git a/gdb/infrun.c b/gdb/infrun.c
index edfb5ab0a91..6cfb097c03a 100644
--- a/gdb/infrun.c
+++ b/gdb/infrun.c
@@ -8004,6 +8004,7 @@ insert_exception_resume_breakpoint (struct thread_info *tp,
 	  frame = nullptr;
 
 	  bp->thread = tp->global_num;
+	  bp->inferior = -1;
 	  inferior_thread ()->control.exception_resume_breakpoint = bp;
 	}
     }
@@ -8037,6 +8038,7 @@ insert_exception_resume_from_probe (struct thread_info *tp,
   bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
 				       handler, bp_exception_resume).release ();
   bp->thread = tp->global_num;
+  bp->inferior = -1;
   inferior_thread ()->control.exception_resume_breakpoint = bp;
 }
 
diff --git a/gdb/linespec.c b/gdb/linespec.c
index d3def7ae070..93cc68f28e8 100644
--- a/gdb/linespec.c
+++ b/gdb/linespec.c
@@ -254,9 +254,9 @@ enum linespec_token_type
 
 /* List of keywords.  This is NULL-terminated so that it can be used
    as enum completer.  */
-const char * const linespec_keywords[] = { "if", "thread", "task", "-force-condition", NULL };
+const char * const linespec_keywords[] = { "if", "thread", "task", "inferior", "-force-condition", NULL };
 #define IF_KEYWORD_INDEX 0
-#define FORCE_KEYWORD_INDEX 3
+#define FORCE_KEYWORD_INDEX 4
 
 /* A token of the linespec lexer  */
 
diff --git a/gdb/python/py-breakpoint.c b/gdb/python/py-breakpoint.c
index 1b10ccd5415..fc99bbf162c 100644
--- a/gdb/python/py-breakpoint.c
+++ b/gdb/python/py-breakpoint.c
@@ -280,11 +280,69 @@ bppy_set_thread (PyObject *self, PyObject *newvalue, void *closure)
       return -1;
     }
 
+  if (self_bp->bp->inferior != -1 && id != -1)
+    {
+      PyErr_SetString (PyExc_RuntimeError,
+		       _("Cannot have both thread and inferior conditions "
+			 "on a breakpoint"));
+      return -1;
+    }
+
   breakpoint_set_thread (self_bp->bp, id);
 
   return 0;
 }
 
+/* Python function to set the inferior of a breakpoint.  */
+
+static int
+bppy_set_inferior (PyObject *self, PyObject *newvalue, void *closure)
+{
+  gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
+  long id;
+
+  BPPY_SET_REQUIRE_VALID (self_bp);
+
+  if (newvalue == NULL)
+    {
+      PyErr_SetString (PyExc_TypeError,
+		       _("Cannot delete `inferior' attribute."));
+      return -1;
+    }
+  else if (PyLong_Check (newvalue))
+    {
+      if (!gdb_py_int_as_long (newvalue, &id))
+	return -1;
+
+      if (!valid_global_inferior_id (id))
+	{
+	  PyErr_SetString (PyExc_RuntimeError,
+			   _("Invalid inferior ID."));
+	  return -1;
+	}
+    }
+  else if (newvalue == Py_None)
+    id = -1;
+  else
+    {
+      PyErr_SetString (PyExc_TypeError,
+		       _("The value of `inferior' must be an integer or None."));
+      return -1;
+    }
+
+  if (self_bp->bp->thread != -1 && id != -1)
+    {
+      PyErr_SetString (PyExc_RuntimeError,
+		       _("Cannot have both thread and inferior conditions "
+			 "on a breakpoint"));
+      return -1;
+    }
+
+  breakpoint_set_inferior (self_bp->bp, id);
+
+  return 0;
+}
+
 /* Python function to set the (Ada) task of a breakpoint.  */
 static int
 bppy_set_task (PyObject *self, PyObject *newvalue, void *closure)
@@ -689,6 +747,20 @@ bppy_get_thread (PyObject *self, void *closure)
   return gdb_py_object_from_longest (self_bp->bp->thread).release ();
 }
 
+/* Python function to get the breakpoint's inferior ID.  */
+static PyObject *
+bppy_get_inferior (PyObject *self, void *closure)
+{
+  gdbpy_breakpoint_object *self_bp = (gdbpy_breakpoint_object *) self;
+
+  BPPY_REQUIRE_VALID (self_bp);
+
+  if (self_bp->bp->inferior == -1)
+    Py_RETURN_NONE;
+
+  return gdb_py_object_from_longest (self_bp->bp->inferior).release ();
+}
+
 /* Python function to get the breakpoint's task ID (in Ada).  */
 static PyObject *
 bppy_get_task (PyObject *self, void *closure)
@@ -1333,6 +1405,11 @@ static gdb_PyGetSetDef breakpoint_object_getset[] = {
 If the value is a thread ID (integer), then this is a thread-specific breakpoint.\n\
 If the value is None, then this breakpoint is not thread-specific.\n\
 No other type of value can be used.", NULL },
+  { "inferior", bppy_get_inferior, bppy_set_inferior,
+    "Inferior ID for the breakpoint.\n\
+If the value is an inferior ID (integer), then this is an inferior-specific\n\
+breakpoint.  If the value is None, then this breakpoint is not\n\
+inferior-specific.  No other type of value can be used.", NULL },
   { "task", bppy_get_task, bppy_set_task,
     "Thread ID for the breakpoint.\n\
 If the value is a task ID (integer), then this is an Ada task-specific breakpoint.\n\
diff --git a/gdb/testsuite/gdb.linespec/cpcompletion.exp b/gdb/testsuite/gdb.linespec/cpcompletion.exp
index fbe19b49d43..f005707b9da 100644
--- a/gdb/testsuite/gdb.linespec/cpcompletion.exp
+++ b/gdb/testsuite/gdb.linespec/cpcompletion.exp
@@ -1259,8 +1259,8 @@ proc_with_prefix function-labels {} {
 }
 
 # Test that completion after a function name offers keyword
-# (if/task/thread/-force-condition) matches in linespec mode, and also
-# the explicit location options in explicit locations mode.
+# (if/inferior/task/thread/-force-condition) matches in linespec mode,
+# and also the explicit location options in explicit locations mode.
 
 proc_with_prefix keywords-after-function {} {
     set explicit_list \
diff --git a/gdb/testsuite/gdb.linespec/explicit.exp b/gdb/testsuite/gdb.linespec/explicit.exp
index 637470e6763..3845bab8bc6 100644
--- a/gdb/testsuite/gdb.linespec/explicit.exp
+++ b/gdb/testsuite/gdb.linespec/explicit.exp
@@ -412,6 +412,7 @@ namespace eval $testfile {
 	    "-qualified"
 	    "-source"
 	    "if"
+	    "inferior"
 	    "task"
 	    "thread"
 	}
diff --git a/gdb/testsuite/gdb.multi/inferior-specific-bp-1.c b/gdb/testsuite/gdb.multi/inferior-specific-bp-1.c
new file mode 100644
index 00000000000..26cb01911d2
--- /dev/null
+++ b/gdb/testsuite/gdb.multi/inferior-specific-bp-1.c
@@ -0,0 +1,52 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2022 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+volatile int global_var = 0;
+
+static void
+stop_breakpt (void)
+{
+  /* Nothing.  */
+}
+
+static inline void __attribute__((__always_inline__))
+foo (void)
+{
+  int i;
+
+  for (i = 0; i < 10; ++i)
+    global_var = 0;
+}
+
+static void
+bar (void)
+{
+  global_var = 0;
+
+  foo ();
+}
+
+
+int
+main (void)
+{
+  global_var = 0;
+  foo ();
+  bar ();
+  stop_breakpt ();
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.multi/inferior-specific-bp-2.c b/gdb/testsuite/gdb.multi/inferior-specific-bp-2.c
new file mode 100644
index 00000000000..3ddb1a17446
--- /dev/null
+++ b/gdb/testsuite/gdb.multi/inferior-specific-bp-2.c
@@ -0,0 +1,52 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2022 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+static int bar (void);
+static int baz (void);
+static int foo (void);
+
+static void
+stop_breakpt (void)
+{
+  /* Nothing.  */
+}
+
+int
+main (void)
+{
+  int ret = baz ();
+  stop_breakpt ();
+  return ret;
+}
+
+static int
+bar (void)
+{
+  return baz ();
+}
+
+static int
+foo (void)
+{
+  return 0;
+}
+
+static int
+baz (void)
+{
+  return foo ();
+}
diff --git a/gdb/testsuite/gdb.multi/inferior-specific-bp.exp b/gdb/testsuite/gdb.multi/inferior-specific-bp.exp
new file mode 100644
index 00000000000..4e80adf76ae
--- /dev/null
+++ b/gdb/testsuite/gdb.multi/inferior-specific-bp.exp
@@ -0,0 +1,182 @@
+# Copyright 2022 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Test inferior-specific breakpoints.
+
+standard_testfile -1.c -2.c
+
+if {[use_gdb_stub]} {
+    return
+}
+
+set srcfile1 ${srcfile}
+set binfile1 ${binfile}-1
+set binfile2 ${binfile}-2
+
+if {[build_executable ${testfile}.exp ${binfile1} "${srcfile1}"] != 0} {
+    return -1
+}
+
+if {[build_executable ${testfile}.exp ${binfile2} "${srcfile2}"] != 0} {
+    return -1
+}
+
+# Start the first inferior.
+clean_restart ${binfile1}
+if {![runto_main]} {
+    return
+}
+
+# Add a second inferior, and start this one too.
+gdb_test "add-inferior" "Added inferior 2.*" "add empty inferior 2"
+gdb_test "inferior 2" "Switching to inferior 2.*" "switch to inferior 2"
+gdb_load $binfile2
+if {![runto_main]} {
+    return
+}
+
+# Try to create a breakpoint using both the 'inferior' and 'thread' keywords,
+# this should fail.  Try with the keywords in both orders just in case the
+# parser has a bug.
+gdb_test "break foo thread 1.1 inferior 1" \
+    "Cannot have both 'thread' and 'inferior' conditions on a breakpoint"
+gdb_test "break foo inferior 1 thread 1.1" \
+    "Cannot have both 'thread' and 'inferior' conditions on a breakpoint"
+
+# While we're here, check that we can't create a watchpoint with both thread
+# and inferior keywords.  As above, test with keywords in both orders.
+foreach type {watch rwatch awatch} {
+    gdb_test "$type global_var thread 1.1 inferior 1" \
+	"Cannot have both 'thread' and 'inferior' conditions on a watchpoint"
+    gdb_test "$type global_var inferior 1 thread 1.1" \
+	"Cannot have both 'thread' and 'inferior' conditions on a watchpoint"
+}
+
+# Clear out any other breakpoints.
+delete_breakpoints
+
+# Create an inferior-specific breakpoint.  Use gdb_test instead of
+# gdb_breakpoint here as we want to check the breakpoint was placed in
+# multiple locations.
+gdb_test "break foo inferior 1" \
+    "Breakpoint $decimal at $hex: foo\\. \\(3 locations\\)"
+
+set saw_header false
+set location_count 0
+set saw_inf_cond false
+gdb_test_multiple "info breakpoints" "" {
+    -re "\r\nNum\\s+\[^\r\n\]+\r\n" {
+	exp_continue
+    }
+
+    -re "^$decimal\\s+breakpoint\\s+keep\\s+y\\s+<MULTIPLE>\\s*\r\n" {
+	set saw_header true
+	exp_continue
+    }
+
+    -re "^\\s+stop only in inferior 1\r\n" {
+	set saw_inf_cond true
+	exp_continue
+    }
+
+    -re "^$decimal\\.\[123\]\\s+y\\s+ $hex in foo at \[^\r\n\]+ inf \[12\]\r\n" {
+	incr location_count
+	exp_continue
+    }
+
+    -re "^$gdb_prompt $" {
+	with_test_prefix $gdb_test_name {
+	    gdb_assert { $saw_header }
+	    gdb_assert { $location_count == 3 }
+	    gdb_assert { $saw_inf_cond }
+	}
+    }
+}
+
+# Create a multi-inferior breakpoint to stop at.
+gdb_test "break stop_breakpt"
+
+# Now resume inferior 2, this should reach 'stop_breakpt'.
+gdb_test "continue" "hit Breakpoint $decimal\.$decimal, stop_breakpt \\(\\) .*" \
+    "continue in inferior 2"
+
+# Switch to inferior 1, and try there.
+gdb_test "inferior 1" ".*" \
+    "select inferior 1 to check the inferior-specific b/p works"
+gdb_test "continue " \
+    "Thread 1\\.${decimal}\[^\r\n\]* hit Breakpoint $decimal\.$decimal, foo \\(\\) .*" \
+    "first continue in inferior 1"
+
+# Now back to inferior 2, let the inferior exit, the inferior-specific
+# breakpoint should not be deleted.
+gdb_test "inferior 2" ".*" \
+    "switch back to allow inferior 2 to exit"
+gdb_test "continue" "Inferior 2 \[^\r\n\]+ exited normally.*" \
+    "allow inferior 2 to exit"
+
+gdb_test "inferior 1" ".*" \
+    "select inferior 1 to check inferior-specific b/p still works"
+gdb_test "continue " "hit Breakpoint $decimal\.$decimal, foo \\(\\) .*" \
+    "second continue in inferior 1"
+gdb_test "continue " "hit Breakpoint $decimal\.$decimal, stop_breakpt \\(\\) .*" \
+    "third continue in inferior 1"
+
+# Now allow inferior 1 to exit, the inferior specific breakpoint should be
+# deleted.
+gdb_test "continue" \
+    [multi_line \
+	 "\\\[Inferior 1 \[^\r\n\]+ exited normally\\\]" \
+	 "Inferior-specific breakpoint $decimal deleted - inferior 1 has exited\\."]
+
+set saw_header false
+set location_count 0
+set saw_inf_cond false
+gdb_test_multiple "info breakpoints" "info breakpoint after inferior 1 exited" {
+    -re "^info breakpoints\r\n" {
+	exp_continue
+    }
+
+    -re "^Num\\s+\[^\r\n\]+\r\n" {
+	exp_continue
+    }
+
+    -re "^$decimal\\s+breakpoint\\s+keep\\s+y\\s+<MULTIPLE>\\s*\r\n" {
+	set saw_header true
+	exp_continue
+    }
+
+    -re "^\\s+stop only in inferior 1\r\n" {
+	# This should not happen, this breakpoint should have been deleted.
+	set saw_inf_cond true
+	exp_continue
+    }
+
+    -re "^\\s+breakpoint already hit 2 times\r\n" {
+	exp_continue
+    }
+
+    -re "^$decimal\\.\[12\]\\s+y\\s+ $hex in stop_breakpt at \[^\r\n\]+ inf \[12\]\r\n" {
+	incr location_count
+	exp_continue
+    }
+
+    -re "^$gdb_prompt $" {
+	with_test_prefix $gdb_test_name {
+	    gdb_assert { $saw_header }
+	    gdb_assert { $location_count == 2 }
+	    gdb_assert { !$saw_inf_cond }
+	}
+    }
+}
diff --git a/gdb/testsuite/gdb.python/py-breakpoint.exp b/gdb/testsuite/gdb.python/py-breakpoint.exp
index 9535040e3a2..30e2ab1e4d8 100644
--- a/gdb/testsuite/gdb.python/py-breakpoint.exp
+++ b/gdb/testsuite/gdb.python/py-breakpoint.exp
@@ -111,6 +111,8 @@ proc_with_prefix test_bkpt_basic { } {
 	"Get Breakpoint List" 0
     gdb_test "python print (blist\[1\].thread)" \
 	"None" "Check breakpoint thread"
+    gdb_test "python print (blist\[1\].inferior)" \
+	"None" "Check breakpoint inferior"
     gdb_test "python print (blist\[1\].type == gdb.BP_BREAKPOINT)" \
 	"True" "Check breakpoint type"
     gdb_test "python print (blist\[0\].number)" \
@@ -213,6 +215,46 @@ proc_with_prefix test_bkpt_cond_and_cmds { } {
 	"check number of lines in commands"
 }
 
+# Test breakpoint thread and inferior attributes.
+proc_with_prefix test_bkpt_thread_and_inferior { } {
+    global srcfile testfile hex decimal
+
+    # Start with a fresh gdb.
+    clean_restart ${testfile}
+
+    if {![runto_main]} {
+	return 0
+    }
+
+    with_test_prefix "thread" {
+	delete_breakpoints
+	gdb_test "break multiply thread 1"
+	gdb_test "python bp = gdb.breakpoints ()\[0\]"
+	gdb_test "python print(bp.thread)" "1"
+	gdb_test "python print(bp.inferior)" "None"
+	gdb_test "python bp.inferior = 1" \
+	    "RuntimeError: Cannot have both thread and inferior conditions on a breakpoint.*"
+	gdb_test_no_output "python bp.thread = None"
+	gdb_test_no_output "python bp.inferior = 1" \
+	    "set the inferior now the thread has been cleared"
+	gdb_test "info breakpoints" "stop only in inferior 1\r\n.*"
+    }
+
+    with_test_prefix "inferior" {
+	delete_breakpoints
+	gdb_test "break multiply inferior 1"
+	gdb_test "python bp = gdb.breakpoints ()\[0\]"
+	gdb_test "python print(bp.thread)" "None"
+	gdb_test "python print(bp.inferior)" "1"
+	gdb_test "python bp.thread = 1" \
+	    "RuntimeError: Cannot have both thread and inferior conditions on a breakpoint.*"
+	gdb_test_no_output "python bp.inferior = None"
+	gdb_test_no_output "python bp.thread = 1" \
+	    "set the thread now the inferior has been cleared"
+	gdb_test "info breakpoints" "stop only in thread 1\r\n.*"
+    }
+}
+
 proc_with_prefix test_bkpt_invisible { } {
     global srcfile testfile hex decimal
 
@@ -849,6 +891,7 @@ proc_with_prefix test_bkpt_auto_disable { } {
 test_bkpt_basic
 test_bkpt_deletion
 test_bkpt_cond_and_cmds
+test_bkpt_thread_and_inferior
 test_bkpt_invisible
 test_hardware_breakpoints
 test_catchpoints
diff --git a/gdb/testsuite/lib/completion-support.exp b/gdb/testsuite/lib/completion-support.exp
index bf9c5ad352c..5f68d198adc 100644
--- a/gdb/testsuite/lib/completion-support.exp
+++ b/gdb/testsuite/lib/completion-support.exp
@@ -27,7 +27,7 @@ namespace eval completion {
     # List of all quote chars, including no-quote at all.
     variable maybe_quoted_list {"" "'" "\""}
 
-    variable keyword_list {"-force-condition" "if" "task" "thread"}
+    variable keyword_list {"-force-condition" "if" "inferior" "task" "thread"}
 
     variable explicit_opts_list \
 	{"-function" "-label" "-line" "-qualified" "-source"}
-- 
2.25.4