Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uunet!portal!cup.portal.com!Gary_Edmunds_Miller
From: Gary_Edmunds_Miller@cup.portal.com
Newsgroups: gnu.emacs.bug
Subject: EMACS 18.55 bug in alloc.c
Message-ID: <24057@cup.portal.com>
Date: 14 Nov 89 18:35:28 GMT
Organization: The Portal System (TM)
Lines: 23

I was just using Emacs version 18.55 to test a recent port of 
GCC to a Charles River Data Systems/Universe 32.  In the
process a bug in alloc.c in Emacs 18.55 was found that causes a core
dump. As an approximation of the code:
-----
char staticvec1[NSTATICS * sizeof(Lisp_Object *)] = {0};

#define staticvec((Lisp_Object **)) staticvec1)

void
staticpro(varaddress)
        Lisp_Object *varaddress;
{
	staticvec[staticidx++] = varaddress;
-----
Now it just so happens that staticvec1 was aligned on an ODD byte,
but GCC used a MOVE.L instruction on a 68000.  A word write to an
odd address causes a TRAP on a 68000.  The fix is to define
staticvec1 as an int and to descreas the size of staticvec1 by
sizeof(int).
..
RGDS
GARY