From owner-freebsd-hackers  Mon Mar 22  8: 1: 8 1999
Delivered-To: freebsd-hackers@freebsd.org
Received: from plunger.gdeb.com (plunger.gdeb.com [153.11.11.3])
	by hub.freebsd.org (Postfix) with ESMTP id 761B514D5C
	for <freebsd-hackers@FreeBSD.org>; Mon, 22 Mar 1999 08:00:56 -0800 (PST)
	(envelope-from eischen@vigrid.com)
Received: from orion.caen.gdeb.com ([153.11.109.11])
	by plunger.gdeb.com (8.9.1a/8.9.1/CSC-E_4.1) with ESMTP id KAA16849;
	Mon, 22 Mar 1999 10:57:33 -0500 (EST)
Received: from clcrtr.clc.gdeb.com (clcrtr [153.11.109.129])
	by orion.caen.gdeb.com (8.8.8/8.8.8) with SMTP id KAA07152;
	Mon, 22 Mar 1999 10:59:43 -0500 (EST)
	(envelope-from eischen@vigrid.com)
Message-ID: <36F668EE.2781E494@vigrid.com>
Date: Mon, 22 Mar 1999 10:59:42 -0500
From: "Daniel M. Eischen" <eischen@vigrid.com>
X-Mailer: Mozilla 3.0Gold (X11; I; FreeBSD 2.2.7-STABLE i386)
MIME-Version: 1.0
To: freebsd-hackers@FreeBSD.org
Subject: Fatal GCC error found
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Sender: owner-freebsd-hackers@FreeBSD.ORG
Precedence: bulk
X-Loop: FreeBSD.ORG

I found something that causes a fatal GCC bug.  This is with
both the stock FreeBSD gcc and the port for gcc-28.  This can
be reproduced by building the Ada-aware GDB port found at:

  ftp://ftp.pcnet.com/users/eischen/FreeBSD/adagdb-4.17-port.tar.gz

and building with 'make EXPOSE_FATAL_GCC_ERROR=yes'.  If you
don't define EXPOSE_FATAL_GCC_ERROR, a work-around patch is
applied and the port successfully builds.

For anyone interested in tracking this down, here's how it
aborts:

  cc -c -O -pipe -DFREEBSD_ELF     -I. -I. -I./config -DHAVE_CONFIG_H \
   -I./../include/opcode -I./../readline  -I../bfd -I./../bfd  -I./../include \
   ada-lang.c
  ada-lang.c: In function `ada_evaluate_subexp':
  ada-lang.c:5951: internal error--insn does not satisfy its constraints:
  (insn 2997 2996 4542 (parallel[ 
              (set (reg:DI 1 %edx)
                  (minus:DI (reg:DI 0 %eax)
                      (reg/v:DI 3 %ebx)))
              (clobber (scratch:SI))
          ] ) 135 {subdi3} (insn_list 2982 (insn_list 2994 (nil)))
      (expr_list:REG_DEAD (mem:DI (plus:SI (reg:SI 6 %ebp)
                  (const_int -64)))
          (expr_list:REG_DEAD (reg/v:DI 3 %ebx)
              (expr_list:REG_UNUSED (scratch:SI)
                  (nil)))))
  cc: Internal compiler error: program cc1 got fatal signal 6
  *** Error code 1

The fix to this is to change 2 ocurrences of the following line:

      (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1);

to
      (*pos) = (*pos) + 3 + BYTES_TO_EXP_ELEM (tem + 1);

If someone knows how to fix this, please let me know.  I'm going to
file a PR on this later tonight.

Dan Eischen
eischen@vigrid.com


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message