Re: c/6815: [3.2/3.3 regression] ICE with longjmp if -fprofile-arcs -O is specified

["Christian Ehrhardt" <ehrhardt@mathematik.uni-ulm.de>]

The following reply was made to PR c/6815; it has been noted by GNATS.

From: "Christian Ehrhardt" <ehrhardt@mathematik.uni-ulm.de>
To: gcc-gnats@gcc.gnu.org, gcc-prs@gcc.gnu.org, gcc-bugs@gcc.gnu.org,
  nobody@gcc.gnu.org, dtucker@zip.com.au
Cc: rth@redhat.com
Subject: Re: c/6815: [3.2/3.3 regression] ICE with longjmp if -fprofile-arcs -O is specified
Date: Thu, 12 Dec 2002 13:37:26 +0100

 http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=6815
 
 These messages on gcc@gcc.gnu.org are about the same problem. This mail
 is mainly meant to make sure that this information is attached to the
 audit trail of PR 6815:
 
 http://gcc.gnu.org/ml/gcc/2002-12/msg00377.html
 http://gcc.gnu.org/ml/gcc/2002-12/msg00378.html
 http://gcc.gnu.org/ml/gcc/2002-12/msg00458.html
 http://gcc.gnu.org/ml/gcc/2002-12/msg00475.html
 
 Citing rth in one of theses mails:
 | Before the invocation of the profiling routines, no successors is correct.
 | During the invocation of the profiling routines, however, we add fake 
 | edges from calls to the exit block.  I would not expect this to change
 | for a noreturn function like longjmp.
 |
 | So I guess the quesion is "where did you get this null, exactly?"
 
 The crash is in cfgrtl.c:1314 in function insert_insn_on_edge in this
 piece of code:
 
 | void
 | insert_insn_on_edge (pattern, e)
 |      rtx pattern;
 |      edge e;
 | {
 |   /* We cannot insert instructions on an abnormal critical edge.
 |      It will be easier to find the culprit if we die now.  */
 |   if ((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e))
 |     abort ();
 | [ ... ]
 
 where e is NULL. insert_insn_on_edge in turn is called from
 flow_call_edges_add in cfganal.c:325 with this piece of code:
 
 | for (e = bb->succ; e; e = e->succ_next)
 |   if (e->dest == EXIT_BLOCK_PTR)
 |     break;
 |
 | insert_insn_on_edge (gen_rtx_USE (VOIDmode, const0_rtx), e);
 | commit_edge_insertions ();
 
 which looks a bit strange if we keep in mind that insert_insn_on_edge
 will crash if the second parameter is NULL.
 
     regards  Christian
 
 -- 
 THAT'S ALL FOLKS!