Fix wrong-docstring problem introduced with hash-consing.

* eval.c (Fautoload): Set doc to a unique number rather than to 0.
Remove unused var `args'.
* lisp.h (XSETCARFASTINT, XSETCDRFASTINT): Remove.
(LOADHIST_ATTACH): Wrap with do...while to avoid surprises for callers.
* doc.c (store_function_docstring): Use XSETCAR.

1 files changed, 5 insertions, 4 deletions

diff --git a/src/eval.c b/src/eval.c
index 184455f7e7d..120365f5f57 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -2134,8 +2134,6 @@ this does nothing and returns nil.  */)
      (function, file, docstring, interactive, type)
      Lisp_Object function, file, docstring, interactive, type;
 {
-  Lisp_Object args[4];
-
   CHECK_SYMBOL (function);
   CHECK_STRING (file);
 
@@ -2151,8 +2149,11 @@ this does nothing and returns nil.  */)
     LOADHIST_ATTACH (Fcons (Qautoload, function));
   else
     /* We don't want the docstring in purespace (instead,
-       Snarf-documentation should (hopefully) overwrite it).  */
-    docstring = make_number (0);
+       Snarf-documentation should (hopefully) overwrite it).
+       We used to use 0 here, but that leads to accidental sharing in
+       purecopy's hash-consing, so we use a (hopefully) unique integer
+       instead.  */
+    docstring = make_number (XHASH (function));
   return Ffset (function,
                 Fpurecopy (list5 (Qautoload, file, docstring,
                                   interactive, type)));