c/10336: [3.4 regression] ICE with -Wunreachable-code

c/10336: [3.4 regression] ICE with -Wunreachable-code

[reichelt]

>Number:         10336
>Category:       c
>Synopsis:       [3.4 regression] ICE with -Wunreachable-code
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          ice-on-legal-code
>Submitter-Id:   net
>Arrival-Date:   Mon Apr 07 12:06:00 UTC 2003
>Closed-Date:
>Last-Modified:
>Originator:     reichelt@igpm.rwth-aachen.de
>Release:        gcc 3.4-20030404
>Organization:
>Environment:
i686-pc-linux-gnu
>Description:
The reduced testcase for the switch -Wunreachable-code
from PR 8828 now causes an ICE on mainline:

Just compile with "gcc -c -Wunreachable-code"

---------------------snip here-------------------------
void foo(int i)
{
  switch(i) {
    case 0:
      break;
    case 1:
      break;
  }
}
---------------------snip here-------------------------

The bug was introduced on April 3rd or 4th.
>How-To-Repeat:
gcc -c -Wunreachable-code
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:

Re: c/10336: [3.4 regression] ICE with -Wunreachable-code

[Volker Reichelt]

The following reply was made to PR middle-end/10336; it has been noted by GNATS.

From: Volker Reichelt <reichelt@igpm.rwth-aachen.de>
To: s.bosscher@student.tudelft.nl
Cc: gcc-gnats@gcc.gnu.org, gcc-bugs@gcc.gnu.org, nobody@gcc.gnu.org,
 gcc-prs@gcc.gnu.org, jason@redhat.com
Subject: Re: c/10336: [3.4 regression] ICE with -Wunreachable-code
Date: Mon, 07 Apr 2003 16:16:04 +0200 (CEST)

 On  7 Apr, Steven Bosscher wrote:
 > 
 > Does this help?
 
 Yes, this does indeed help (I just ran a full bootstrap and the ICE
 went away).
 
 Jason, you've applied the last patch to the code in jump.c,
 what do you think? Should the patch be applied to mainline?
 Should it also be applied to 3.2 and 3.3 branch, although
 the problem didn't show up on those branches?
 
 Regards,
 Volker
 
 http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=10336
 
 

Re: c/10336: [3.4 regression] ICE with -Wunreachable-code

[Steven Bosscher]

The following reply was made to PR c/10336; it has been noted by GNATS.

From: Steven Bosscher <s.bosscher@student.tudelft.nl>
To: gcc-gnats@gcc.gnu.org, reichelt@igpm.rwth-aachen.de,
	gcc-bugs@gcc.gnu.org, nobody@gcc.gnu.org, gcc-prs@gcc.gnu.org
Cc:  
Subject: Re: c/10336: [3.4 regression] ICE with -Wunreachable-code
Date: Mon, 07 Apr 2003 15:00:08 +0200

 http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=10336
 
 Does this help?
 
 Index: jump.c
 ===================================================================
 RCS file: /cvs/gcc/gcc/gcc/jump.c,v
 retrieving revision 1.221
 diff -c -3 -p -r1.221 jump.c
 *** jump.c    4 Apr 2003 01:21:56 -0000    1.221
 --- jump.c    7 Apr 2003 12:59:17 -0000
 *************** never_reached_warning (avoided_insn, fin
 *** 1912,1918 ****
     /* Back up to the first of any NOTEs preceding avoided_insn; flow passes
        us the head of a block, a NOTE_INSN_BASIC_BLOCK, which often follows
        the line note.  */
 !   for (insn = PREV_INSN (avoided_insn); ; insn = PREV_INSN (insn))
       if (GET_CODE (insn) != NOTE)
         {
       insn = NEXT_INSN (insn);
 --- 1912,1918 ----
     /* Back up to the first of any NOTEs preceding avoided_insn; flow passes
        us the head of a block, a NOTE_INSN_BASIC_BLOCK, which often follows
        the line note.  */
 !   for (insn = PREV_INSN (avoided_insn); insn; insn = PREV_INSN (insn))
       if (GET_CODE (insn) != NOTE)
         {
       insn = NEXT_INSN (insn);