Restore 'command-debug-status' functionality

* src/callint.c (Fcall_interactively): Bind command-debug-status
to nil.  This restores functionality inadvertently removed in
Emacs 25.1.  (Bug#24555)

* lisp/subr.el (command-debug-status): Declare obsolete.

* doc/lispref/debugging.texi (Internals of Debugger): Document
that 'command-debug-status' is obsolete.

3 files changed, 10 insertions, 1 deletions

diff --git a/doc/lispref/debugging.texi b/doc/lispref/debugging.texi
index 2f83b4040fa..c88a2fa60e0 100644
--- a/doc/lispref/debugging.texi
+++ b/doc/lispref/debugging.texi
@@ -654,6 +654,8 @@ invocation.
 The advantage of using this variable rather than an ordinary global
 variable is that the data will never carry over to a subsequent command
 invocation.
+
+This variable is obsolete and will be removed in future versions.
 @end defvar
 
 @defun backtrace-frame frame-number
diff --git a/lisp/subr.el b/lisp/subr.el
index 9c717e16b94..a3aef2e4a5c 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -1377,6 +1377,9 @@ is converted into a string by expressing it in decimal."
 (make-obsolete 'process-filter-multibyte-p nil "23.1")
 (make-obsolete 'set-process-filter-multibyte nil "23.1")
 
+(make-obsolete-variable 'command-debug-status
+                        "expect it to be removed in a future version." "25.2")
+
 ;; Lisp manual only updated in 22.1.
 (define-obsolete-variable-alias 'executing-macro 'executing-kbd-macro
   "before 19.34")
diff --git a/src/callint.c b/src/callint.c
index 053ee6cdaa5..c0afc7b20bd 100644
--- a/src/callint.c
+++ b/src/callint.c
@@ -837,7 +837,10 @@ invoke it.  If KEYS is omitted or nil, the return value of
   kset_last_command (current_kboard, save_last_command);
 
   {
-    Lisp_Object val = Ffuncall (nargs, args);
+    Lisp_Object val;
+    specbind (Qcommand_debug_status, Qnil);
+
+    val = Ffuncall (nargs, args);
     val = unbind_to (speccount, val);
     SAFE_FREE ();
     return val;
@@ -894,6 +897,7 @@ syms_of_callint (void)
   DEFSYM (Qhandle_shift_selection, "handle-shift-selection");
   DEFSYM (Qread_number, "read-number");
   DEFSYM (Qfuncall_interactively, "funcall-interactively");
+  DEFSYM (Qcommand_debug_status, "command-debug-status");
   DEFSYM (Qenable_recursive_minibuffers, "enable-recursive-minibuffers");
   DEFSYM (Qmouse_leave_buffer_hook, "mouse-leave-buffer-hook");