Abolish max-specpdl-size (bug#57911)

The max-lisp-eval-depth limit is sufficient to prevent unbounded stack
growth including the specbind stack; simplify matters for the user by
not having them to worry about two different limits.  This change
turns max-specpdl-size into a harmless variable with no effects,
to keep existing code happy.

* lisp/subr.el (max-specpdl-size):
Define as an ordinary (but obsolete) dynamic variable.
* admin/grammars/Makefile.in:
* doc/lispintro/emacs-lisp-intro.texi (Loops & Recursion):
* doc/lispref/control.texi (Cleanups):
* doc/lispref/edebug.texi (Checking Whether to Stop):
* doc/lispref/eval.texi (Eval):
* doc/lispref/variables.texi (Local Variables):
* doc/misc/calc.texi (Recursion Depth):
Update documentation.
* etc/NEWS: Announce.
* src/eval.c
(FletX): Use safe iteration to guard against circular bindings list.
(syms_of_eval): Remove old max-specpdl-size definition.
(init_eval_once, restore_stack_limits, call_debugger)
(signal_or_quit, grow_specpdl_allocation):
* leim/Makefile.in:
* lisp/Makefile.in:
* lisp/calc/calc-stuff.el (calc-more-recursion-depth)
(calc-less-recursion-depth):
* lisp/calc/calc.el (calc-do):
* lisp/cedet/semantic/ede-grammar.el (ede-proj-makefile-insert-rules):
* lisp/cedet/semantic/grammar.el (semantic-grammar-batch-build-one-package):
* lisp/cus-start.el (standard):
* lisp/emacs-lisp/comp.el (comp--native-compile):
* lisp/emacs-lisp/edebug.el (edebug-max-depth):
(edebug-read-and-maybe-wrap-form, edebug-default-enter):
* lisp/emacs-lisp/regexp-opt.el (regexp-opt):
* lisp/eshell/esh-mode.el (eshell-mode):
* lisp/loadup.el (max-specpdl-size):
* lisp/mh-e/mh-e.el (mh-invisible-headers):
* lisp/net/shr.el (shr-insert-document, shr-descend):
* lisp/play/hanoi.el (hanoi-internal):
* lisp/progmodes/cperl-mode.el:
* src/fileio.c (Fdo_auto_save):
Remove references to and modifications of max-specpdl-size.

lisp/calc/calc-stuff.el

@@ -52,18 +52,14 @@ With a prefix, push that prefix as a number onto the stack."
        (calc-less-recursion-depth n)
      (let ((n (if n (prefix-numeric-value n) 2)))
        (if (> n 1)
-	   (setq max-specpdl-size (* max-specpdl-size n)
-		 max-lisp-eval-depth (* max-lisp-eval-depth n))))
+	   (setq max-lisp-eval-depth (* max-lisp-eval-depth n))))
      (message "max-lisp-eval-depth is now %d" max-lisp-eval-depth))))
 
 (defun calc-less-recursion-depth (n)
   (interactive "P")
   (let ((n (if n (prefix-numeric-value n) 2)))
     (if (> n 1)
-	(setq max-specpdl-size
-	      (max (/ max-specpdl-size n) 600)
-	      max-lisp-eval-depth
-	      (max (/ max-lisp-eval-depth n) 200))))
+	(setq max-lisp-eval-depth (max (/ max-lisp-eval-depth n) 200))))
   (message "max-lisp-eval-depth is now %d" max-lisp-eval-depth))
 
 

lisp/calc/calc.el

@@ -1625,8 +1625,7 @@ See calc-keypad for details."
 	  (error
 	   (if (and (eq (car err) 'error)
 		    (stringp (nth 1 err))
-		    (string-match "max-specpdl-size\\|max-lisp-eval-depth"
-				  (nth 1 err)))
+		    (string-search "max-lisp-eval-depth" (nth 1 err)))
                (error (substitute-command-keys
                        "Computation got stuck or ran too long.  Type \\`M' to increase the limit"))
 	     (setq calc-aborted-prefix nil)