bug#20862: 25.0.50; 32-bit Emacs configured --with-wide-int miscompiles CL

[Paul Eggert <eggert@cs.ucla.edu>]

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Andreas Schwab wrote:
> That isn't true.  #: prefixed symbols are uninterned symbols.

Good point, thanks.  The doc I quoted predates the #: syntax, and evidently 
wasn't updated when the #: syntax was introduced and used.  Since that doc 
wording is wrong, and there's now no reason to initialize cl--gensym-counter to 
anything other than 0, I boldly installed the attached patch.  It passes 'make 
bootstrap' and 'make check' (at least, as well as 'make check' did before -- it 
always fails for me in epg-roundtrip-2).

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From c66ff5757c6eeb495eeb283f34fc0713d1fb5270 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Sat, 27 Jun 2015 10:57:02 -0700
Subject: [PATCH] Initialize cl--gensym-counter to 0

Previously it was initialized to a random value, which made it
harder to reproduce earlier Emacs runs.  The need for a random
value went away when Emacs introduced and used the #: syntax for
uninterned symbols (Bug#20862).
* doc/misc/cl.texi (Creating Symbols, Common Lisp Compatibility):
Document that cl--gensym-counter now starts with 0.
* lisp/emacs-lisp/cl-lib.el (cl--gensym-counter): Remove.
(cl--random-time): Move to near only remaining use.
* lisp/emacs-lisp/cl-macs.el (cl--gensym-counter): Initialize to 0.
---
 doc/misc/cl.texi           | 15 +++------------
 lisp/emacs-lisp/cl-lib.el  | 15 +++++----------
 lisp/emacs-lisp/cl-macs.el |  2 +-
 3 files changed, 9 insertions(+), 23 deletions(-)

diff --git a/doc/misc/cl.texi b/doc/misc/cl.texi
index d7b3f4a..1f38ca9 100644
--- a/doc/misc/cl.texi
+++ b/doc/misc/cl.texi
@@ -2877,14 +2877,8 @@ their names will not conflict with ``real'' variables in the user's
 code.
 
 (Internally, the variable @code{cl--gensym-counter} holds the counter
-used to generate names.  It is incremented after each use.  In Common
-Lisp this is initialized with 0, but this package initializes it with
-a random time-dependent value to avoid trouble when two files that
-each used @code{cl-gensym} in their compilation are loaded together.
-Uninterned symbols become interned when the compiler writes them out
-to a file and the Emacs loader loads them, so their names have to be
-treated a bit more carefully than in Common Lisp where uninterned
-symbols remain uninterned after loading.)
+used to generate names.  It is initialized with zero and incremented
+after each use.)
 @end defun
 
 @defun cl-gentemp &optional x
@@ -4543,10 +4537,7 @@ example, local @code{special} declarations, which are purely
 advisory in Emacs Lisp, do not rigorously obey the scoping rules
 set down in Steele's book.
 
-The variable @code{cl--gensym-counter} starts out with a pseudo-random
-value rather than with zero.  This is to cope with the fact that
-generated symbols become interned when they are written to and
-loaded back from a file.
+The variable @code{cl--gensym-counter} starts out with zero.
 
 The @code{cl-defstruct} facility is compatible, except that structures
 are of type @code{:type vector :named} by default rather than some
diff --git a/lisp/emacs-lisp/cl-lib.el b/lisp/emacs-lisp/cl-lib.el
index b6f3a79..2dd0519 100644
--- a/lisp/emacs-lisp/cl-lib.el
+++ b/lisp/emacs-lisp/cl-lib.el
@@ -249,16 +249,6 @@ so that they are registered at compile-time as well as run-time."
       `(progn ,@body))))           ; Avoid loading cl-macs.el for cl-eval-when.
 
 
-;;; Symbols.
-
-(defun cl--random-time ()
-  (let* ((time (copy-sequence (current-time-string))) (i (length time)) (v 0))
-    (while (>= (cl-decf i) 0) (setq v (+ (* v 3) (aref time i))))
-    v))
-
-(defvar cl--gensym-counter (* (logand (cl--random-time) 1023) 100))
-
-
 ;;; Numbers.
 
 (define-obsolete-function-alias 'cl-floatp-safe 'floatp "24.4")
@@ -298,6 +288,11 @@ If true return the decimal value of digit CHAR in RADIX."
   (let ((n (aref cl-digit-char-table char)))
     (and n (< n (or radix 10)) n)))
 
+(defun cl--random-time ()
+  (let* ((time (copy-sequence (current-time-string))) (i (length time)) (v 0))
+    (while (>= (cl-decf i) 0) (setq v (+ (* v 3) (aref time i))))
+    v))
+
 (defvar cl--random-state
   (vector 'cl--random-state-tag -1 30 (cl--random-time)))
 
diff --git a/lisp/emacs-lisp/cl-macs.el b/lisp/emacs-lisp/cl-macs.el
index 636c543..5bcf088 100644
--- a/lisp/emacs-lisp/cl-macs.el
+++ b/lisp/emacs-lisp/cl-macs.el
@@ -161,7 +161,7 @@ whether X is known at compile time, macroexpand it completely in
 
 ;;; Symbols.
 
-(defvar cl--gensym-counter)
+(defvar cl--gensym-counter 0)
 ;;;###autoload
 (defun cl-gensym (&optional prefix)
   "Generate a new uninterned symbol.
-- 
2.1.0