Staticpro executing_kbd_macro

* src/macros.c (syms_of_macros): Staticpro executing_kbd_macro.
(executing_kbd_macro): Update comment.
* src/macros.h (executing_kbd_macro): Remove redundant comment.

src/macros.c

@@ -35,7 +35,8 @@ EMACS_INT executing_kbd_macro_iterations;
 /* This is the macro that was executing.
    This is not bound at each level,
    so after an error, it describes the innermost interrupted macro.
-   We use it only as a kind of flag, so no need to protect it.  */
+   We use it only as a kind of flag; it could be a simple bool, but we
+   keep the string/vector around to aid debugging.  */
 
 Lisp_Object executing_kbd_macro;
 
@@ -428,6 +429,9 @@ This is run whether the macro ends normally or prematurely due to an error.  */)
 The value is the symbol `append' while appending to the definition of
 an existing macro.  */);
 
+  executing_kbd_macro = Qnil;
+  staticpro (&executing_kbd_macro);
+
   DEFVAR_LISP ("executing-kbd-macro", Vexecuting_kbd_macro,
 	       doc: /* Currently executing keyboard macro (string or vector).
 This is nil when not executing a keyboard macro.  */);

src/macros.h

@@ -28,10 +28,6 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 
 extern EMACS_INT executing_kbd_macro_iterations;
 
-/* This is the macro that was executing.
-   This is not bound at each level,
-   so after an error, it describes the innermost interrupted macro.  */
-
 extern Lisp_Object executing_kbd_macro;
 
 /* Finish defining the current keyboard macro.  */