Re: subtle byte-compiler bug

[Andreas Schwab <schwab@suse.de>]

David PONCE <david.ponce@wanadoo.fr> writes:

> I finally got a little time to investigate on that problem and
> discovered that the bug is not in the byte-compiler but in the
> `prin1' primitive.
>
> Sometimes `prin1' print incorrect uninterned symbol references,
> that can result in writing invalid byte-compiled code.

Thanks for the testcase.  I have installed this change to fix the bug:

	* print.c (print_preprocess) <case Lisp_Vectorlike>: Only mask
	size if PSEUDOVECTOR_FLAG is set.

Index: print.c
===================================================================
RCS file: /cvsroot/emacs/emacs/src/print.c,v
retrieving revision 1.196
retrieving revision 1.197
diff -u -a -p -a -u -p -r1.196 -r1.197
--- print.c	31 Dec 2003 00:24:28 -0000	1.196
+++ print.c	8 Jan 2004 00:15:52 -0000	1.197
@@ -1342,7 +1342,9 @@ print_preprocess (obj)
 	  goto loop;
 
 	case Lisp_Vectorlike:
-	  size = XVECTOR (obj)->size & PSEUDOVECTOR_SIZE_MASK;
+	  size = XVECTOR (obj)->size;
+	  if (size & PSEUDOVECTOR_FLAG)
+	    size &= PSEUDOVECTOR_SIZE_MASK;
 	  for (i = 0; i < size; i++)
 	    print_preprocess (XVECTOR (obj)->contents[i]);
 	  break;

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
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